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Prevalence of reported sleeplessness in Northern Norway in relation to sex, age and season
Abstract
As part of a comprehensive population health survey in the municipality of Tromsø, north of the Arctic Circle, men between 20 and 54 years and women between 20 and 49 years were presented a questionnaire containing questions about sleeplessness and its possible association with season. Of the 14,667 respondents, 41.7% of the women and 29.9% of the men said they were sometimes bothered by insomnia. Insomnia not associated with any special time of the year was reported by 16.9% of women and 16.2% of men; insomnia in the "dark period" (midwinter insomnia) was reported by 17.6% of women and 9.0% of men; insomnia in the midnight-sun period or in spring or autumn was much less common. Difficulty falling asleep was the most common type of insomnia, especially in winter and summer. Overall, the frequency of insomnia increased with increasing age, but with some notable differences with regard to type (initial insomnia showed little relation to age, whereas middle and late insomnia increased markedly with age) and seasonal type (insomnia in the midnight-sun period decreased with age, whereas the other seasonal types increased with age).
... Seasonal changes in sleep problems were studied in many countries [5,14,[34][35][36][37], and studies reported an effect of seasonality on sleep quality. Putilov reported seasonalvariation effects on sleep problems such as daytime sleepiness, difficulties falling asleep, difficulty staying asleep, and premature awakenings [37]. ...
... Another author reported that self-reported measures indicated moderately to strong seasonal differences in insomnia and fatigue prevalence, but no seasonal changes were observed in sleep duration or night awakenings [5]. Few studies reported a strong effect of seasonality on poorer sleep during the winter months [34,35,38]. Pallesen et al. [35] demonstrated that sleep-onset problems and insomnia were more frequent in December compared with June. ...
... Pallesen et al. [35] demonstrated that sleep-onset problems and insomnia were more frequent in December compared with June. Husby and Lingjaerde found an increase in the prevalence of insomnia during winter, but also more sleeplessness during summer [34]. Lukmanjini et al. [14] reported that seasonal variation for insomnia symptoms (trouble falling or staying asleep, or sleeping too much) were similar among age groups of 12-24 and 25+ years. ...
Sleep is crucial for maintaining the recovery and restoration of the body and brain. Less sleep is associated with poor mental and physical performance. Seasonal changes in sleep patterns can be observed. This paper examines seasonal effects on sleep timing, duration, and problems in two Cree First Nation communities in Saskatchewan, Canada. Data were available from a community survey of 588 adults aged 18 years and older (range: 18-78 years) with 44.2% males and 55.8% females. Results are presented using descriptive statistics and a binary logistic-regression model to identify the association between seasonal changes in sleep patterns, and demographic, social, and environmental factors. The participants reported sleeping the least during the spring and summer months and sleeping the most during the fall and winter months. This was further confirmed by sleep hours and the lower proportion of recommended hours of sleep during the spring and summer, and a higher proportion of longer sleep duration during the fall and winter months. There was no significant variation in sleeping onset and wake-up times by season. Overall, there were no significant differences in the prevalence of sleep deprivation, insomnia, and excessive daytime sleepiness by season. When stratified by age group and sex, some differences existed in the prevalence of sleep problems by season. More than two-thirds (68.6%) of the participants reported that there was a change in sleep patterns across seasons, and about 26.0% reported a very or extremely marked change in sleep patterns across seasons. Changes in sleep patterns by season were related to money left at the end of the month and damage caused by dampness in the house.
... The unusual photoperiod, characterized by the total absence of moonlight during polar days, may increase risks of desynchronization and sleep disturbances. 1,2,[6][7][8][9][10][11][12][13] Core temperature (T c ) seems to be a pertinent marker of the biological clock 14,15 owing to its capacity to keep to a rhythm despite extreme environment or extreme physical activity. 16,17 T c has a circadian rhythm (period of ≈ 24 h) with a trough (bathyphase, which encourages sleep mechanisms) in the middle of the night and a peak (acrophase, which promotes wakefulness) at the end of the afternoon. ...
... 1,2,6-12 For example, out of 450 people living in northern Russia, N 80% reported sleep disturbances during times of extreme photoperiod. 9 Regarding scientific expeditions, a reduction in sleep time and quality during an extreme photoperiod was observed. 2,[6][7][8][9] Since 1979, the Arctic ice area has reduced by 11% every 10 y, representing N 500,000 km 2 per decade. ...
... 9 Regarding scientific expeditions, a reduction in sleep time and quality during an extreme photoperiod was observed. 2,[6][7][8][9] Since 1979, the Arctic ice area has reduced by 11% every 10 y, representing N 500,000 km 2 per decade. 28 Thus, in northern Canada, shipping traffic is constantly expanding, from around 100 trips in 2003 to N 350 in 2013. ...
Introduction—Studies have reported circadian desynchronizations and sleep disruptions in onshore populations in the Arctic during the polar day. Although the Arctic region is becoming more accessible by sea and evidence is growing to implicate the importance of fatigue in sailing accidents, no study related to circadian disruptions has focused on sailors. The aim of this study was to observe, during a 155-d polar sailing trip between Greenland and Russia, the evolution of the sleep-wake rhythm and core body temperature (Tc) in a sailor.
Methods—During the expedition, an electronic sleep diary was recorded daily and a continuous measure- 17
ment of Tc using telemetric pills was performed every 10 d (recording depending on transit time, ≈24 h). Ephemerides were manually determined day by day using global positioning systemposition and revealed 3 phases (phase 1: decrease of night duration; phase 2: polar day; phase 3: increase of night duration).
Results—Asignificant difference (Pb0.05)was observed in daily sleep time between phase 2 (7.6±2.5 h) and phase 3 (8±2 h). The period of Tc rhythm changed during the expedition (phase 1: 24.2±0.5 h; phase 2: 25±0.3h; phase 3: 24±0.6 h). Dissociation between Tc rhythm and sleep occurred during phase 2.
Conclusions—Our study observed that during a polar sailing expedition, many circadian disruptions appeared as free-running rhythms or dissociation between sleep and Tc rhythm. Future studies will evaluate effects of these disruptions and their probable association with accident risks.
Keywords: Arctic, polar day, sailing trip, chronobiology, core temperature, sleep
... Seasonal variations in sleep quality or prevalence of insomnia has been well-studied in terms of associations with characteristic seasonal changes in sunlight durations, such as the midnight sun in summer and the dark period in midwinter, especially among Nordic populations. In the epidemiological survey on Norwegian sleep using questionnaires, insomnia was more frequent in winter than in other seasons of the year (6). Other Nordic interview surveys demonstrated that the prevalence of reported insomnia, particularly sleep onset problems, increased from summer to winter in northern Norway but decreased in the southern regions (7). ...
... This indicates the robustness of our results. The seasonal differences in sleep-wake cycles or sleep quality are commonly interpreted as a consequence of the entrainment of circadian rhythm to photoperiodic changes among seasons (4)(5)(6)(7)(53)(54)(55). However, interestingly, meaningful contributions of sunlight durations to sleep quality were not detected in our study. ...
Seasonal changes in meteorological factors [e.g., ambient temperature (Ta), humidity, and sunlight] could significantly influence a person's sleep, possibly resulting in the seasonality of sleep properties (timing and quality). However, population-based studies on sleep seasonality or its association with meteorological factors remain limited, especially those using objective sleep data. Japan has clear seasonality with distinctive changes in meteorological variables among seasons, thereby suitable for examining sleep seasonality and the effects of meteorological factors. This study aimed to investigate seasonal variations in sleep properties in a Japanese population (68,604 individuals) and further identify meteorological factors contributing to sleep seasonality. Here we used large-scale objective sleep data estimated from body accelerations by machine learning. Sleep parameters such as total sleep time, sleep latency, sleep efficiency, and wake time after sleep onset demonstrated significant seasonal variations, showing that sleep quality in summer was worse than that in other seasons. While bedtime did not show clear seasonality, get-up time varied seasonally, with a nadir during summer, and positively correlated with the sunrise time. Estimated by the abovementioned sleep parameters, Ta had a practically meaningful association with sleep quality, indicating that sleep quality worsened with the increase of Ta. This association would partly explain seasonal variations in sleep quality among seasons. In conclusion, Ta had a principal role for seasonality in sleep quality, and the sunrise time chiefly determined the get-up time.
... Earlier studies of the general population in Tromsø have found more symptoms of insomnia and fatigue during the winter as compared to the summer season (Friborg et al. 2014;Husby and Lingjaerde 1990;Johnsen et al. 2013Johnsen et al. , 2012. However, the magnitude of the seasonal variation in insomnia seems to be in the weak-to-moderate range, whereas seasonal changes in fatigue may be more pronounced (Friborg et al. 2014(Friborg et al. , 2018. ...
... In fact, the two items assessing difficulties initiating and maintaining sleep (DIMS) were more frequent during winter months, while early morning awakenings (EMA) were more common during spring. This is consistent with previous studies conducted in Tromsø, showing a delay of the main sleep episode during winter compared to summer (Friborg et al. 2014;Husby and Lingjaerde 1990;Johnsen et al. 2013Johnsen et al. , 2012. Most likely, this reflects a lack of proper entrainment of the circadian rhythm during the Polar Night (Lowden et al. 2019). ...
While some diseases and human behaviors fluctuate consistently with season, the extent of seasonal variations in sleep, especially at high latitudes, is less consistent. We used data from a geographic region (69º North) with extremely large seasonal differences in daylight that had the participants blinded for the current study’s hypotheses. Data were derived from the Tromsø Study (2015–2016), an ongoing population-based study in Northern Norway comprising citizens aged 40 years and older (n = 21,083, participation = 64.7%). The sleep parameters included bedtime, rise time, sleep onset latency (SOL), and total sleep time. Insomnia was defined according to recent diagnostic criteria (International Classification of Sleep Disorders; ICSD-3). We found some evidence of monthly or seasonal variation in sleep problems. Insomnia was most common during the winter months among men, but not women. No seasonal or monthly effects were observed for sleep duration. SOL was slightly longer during the winter months, but the differences were small and hardly of any clinical relevance. The small or non-existing seasonal variation in sleep and sleep difficulties indicate that extreme seasonal variation in daylight is of little influence on sleep status. The city of Tromsø is a modern city with considerable level of artificial light, which may contribute to the observed rather stabile sleep patterns throughout the year.
... Studies in general practice (GP) settings report even higher prevalence: in Germany, Wittchen et al. 33 reported that insomnia prevalence in GP patients were 26.5%; whereas in Norway, Bjorvatn et al. 34 found that more than 50% of GP patients suffered from insomnia, both studies based on the Diagnostic and Statistical Manual for Mental disorders (DSM)-version IV. In one previous Tromsø study (Tromsø II), a high prevalence of self-reported sleep dissatisfaction among 14,667 participants aged 20-54 years was found; 41.7% females and 29.9% men responded yes to the question: "Are you bothered by sleeplessness?" 35 . However this study did not map the frequency of "sleeplessness" 35 . ...
... In one previous Tromsø study (Tromsø II), a high prevalence of self-reported sleep dissatisfaction among 14,667 participants aged 20-54 years was found; 41.7% females and 29.9% men responded yes to the question: "Are you bothered by sleeplessness?" 35 . However this study did not map the frequency of "sleeplessness" 35 . ...
Sleep disturbances cause great impairment in quality of life. In this cross-sectional study, we
analysed questionnaire-collected data from 12,655 persons (30-87 years) who participated in the
sixth survey of the Tromsø Study carried out in 2007-2008. First, using this community-based
sample representative of the general population of northern Norway, we performed a simple
screening to identify individuals with self-reported sleeplessness among those survey participants
who provided information about their sleep patterns. Self-reported sleeplessness was defined as
responding “More than once a week” to the research question “How often have you suffered
from sleeplessness during the last 12 months?” Second, we analysed the associations between selfreported
sleeplessness and the following variables: age, gender, living with a spouse or not, level
of education, employment status, income, smoking, alcohol consumption, body mass index, level
of self-reported health, and psychological distress. Self-reported sleeplessness had a prevalence
of 12.6% in this study population. For both men and women, the variables having the strongest
association with sleeplessness were low levels of self-reported health (men, OR=8.70; women,
OR=5.73) and the presence of psychological distress (men, OR=4.15; women, OR=2.76). In
men, high levels of household income and education were both inversely related to the frequency
of self-reported sleeplessness, while being unemployed was much more strongly associated with
sleeplessness than being employed. We conclude that sleeplessness was frequent in this large
population sample, affecting up to one in eight individuals. Subjects with self-reported sleeplessness
had a distinctly different socio-economic profile and self-perceived health than those without
complaints of sleeplessness.
... The results from the Nordic countries agree with each other. 52,120 In Northern Norway 41.7% of women and 29.9% of men had occasional insomnia. In general complaints of insomnia are more common during winter than during other times of the year 121 . ...
... In the Tromsø study, occurrence of insomnia during summer (summer insomnia) decreased with age, whereas the other seasonal types of insomnia increased with age. 120 . Individuals also differ in their sensitivity or reactivity to seasons. ...
This chapter summarizes some epidemiological principles including analytical studies (interventional and observational) to guide the readers into an understanding of the epidemiological methods of sleep medicine (both clinical and population-based epidemiological studies). This brief section covering basic principles of epidemiology is followed by a description of epidemiological figures of some common sleep disorders.
... Results from other geographical locations lacking a normal alternating daylight and night exposure Ever since the pioneering work of Kleitman and Kleitman [53], high latitudes have been used as a natural laboratory to investigate how large changes in daylight exposure affect sleep/wake regulation. The advantage of such studies is the much larger sample available, as clearly illustrated in the largest published study investigating sleeplessness in Tromso (a Norwegian city above the Arctic circle), encompassing 14 667 participants [54], and the absence of confounding variables such as isolation and confinement. However, the very absence of the other environmental and social stressors specific to Antarctic winters make results more difficult to transpose. ...
... Furthermore, as discussed by Nilssen et al. [55], the prevalence of sleep disturbances due to high latitudes might be related to the geographical origin of participants, as if native subjects had developed an evolutionary advantage, showing to be less sensitive to sleep disturbances when exposed to the changes in daylight exposure associated with higher latitudes. Both Nilssen et al. [55] and Husby and Lingjaerde [54] reported a higher prevalence of disturbed sleep in winter, mainly described as late sleep onset, hence coining the term "midwinter insomnia". In a recent study (N ¼ 4811) carried out in Tromso on seasonal variations in sleepewake patterns, Johnsen et al. [56] found that TST was shorter in summer, with earlier sleep onset and earlier wake up time than in winter. ...
Sleep disturbances are the main health complaints from personnel deployed in Antarctica. The current paper presents a systematic review of research findings on sleep disturbances in Antarctica. The available sources were divided in three categories: results based on questionnaire surveys or sleep logs, studies using actigraphy, and data from polysomnography results. Other areas relevant to the issue were also examined. These included chronobiology, since the changes in photoperiod have been known to affect circadian rhythms; mood disturbances; exercise, sleep and hypoxia; countermeasure investigations in Antarctica; and other locations lacking a normal photoperiod. Based on the combination of our reviewed sources and data outside the field of sleep studies, or from other geographical locations, we defined hypotheses to be confirmed or infirmed, which allowed to summarize a research agenda. Despite the scarcity of sleep research on the Antarctic continent, the present review pinpointed some consistent changes in sleep during the Antarctic winter, the common denominators being a circadian phase delay, poor subjective sleep quality, an increased sleep fragmentation, as well as a decrease in slow wave sleep. Similar changes, albeit less pronounced, were observed during summer. Additional multidisciplinary research is needed to elucidate the mechanisms behind these changes in sleep architecture, and to investigate interventions to improve the sleep quality of the men and women deployed in the Antarctic.
... To the best of our knowledge, only one epidemiologic study has been fully blinded for the research hypothesis of seasonal variations and, in this study, Pallesen et al. (13) found an increase in difficulties initiating sleep in December compared with June in southern Norway. A similar finding was reported in an unblinded retrospective study from the city of Trømsø, located north of the Arctic Circle (14), but for one-third of the participants there were no differences in sleeplessness between summer and midwinter. Adding to the complexity, an unblinded population-based study from Finland found that 20% of the participants reported a worsening of sleep quality during the summer, whereas the comparable figures for the remaining 3 seasons were in the range of 5%-10% (15). ...
... As such, there is still no clear evidence of how (or if) different seasons affect our sleep. Nevertheless, our null findings are in marked contrast to both of these epidemiologic studies, as well as the clinical studies of potential seasonal variations in sleep (13)(14)(15)(16)(17)(18)(19). ...
... Later, several studies have reported various and partly conflicting results regarding the levels of insomnia or mental distress in the dark period. Husby and Lingjaerde found that midwinter insomnia was more common than insomnia in other seasons [13], and Haggag et al. found major seasonal mood variations [14]. Hansen et al. found no significant relationship between participation month and neither depression nor insomnia [15], and Partonen et al. suggested that a high latitude was not responsible for major depression with a seasonal pattern [16]. ...
... 12 Change between seasons: Winter compared to summer. 13 Use of any kind of painkillers weekly or more in the last four weeks. 14 General considering of own health (excellent, good, neither good nor bad, bad, very bad). ...
Background
Prior studies have suggested that the darkness of winter impacts the level of mental distress and sleeping problems. Our study investigated whether people living in the sub-arctic had more sleeping problems or mental distress during winter.
Methods
The cross sectional population Tromsø Study was conducted in Tromsø, North Norway, at 69.4 degrees North and above the Arctic Circle. The study included entire birth cohorts and random samples of the population aged 30 to 87 years. Data was collected continuously from 1 October 2007 to the end of December 2008 except July. 8951 persons completed questionnaires including the HSCL-10 and the MCTQ.
Results
There were no significant differences in the reporting of current mental distress depending on season. Significantly more reported current sleeping problems in winter than in the other seasons, and less sleeping problems was found in spring.
Conclusions
In this sub-arctic population, insomnia was most prevalent in winter, but there were no significant seasonal differences in mental distress. Although some people in the sub-arctic clearly are mentally negatively affected by the darkness of winter, the negative impact of winter on mental distress for the adult population is not conclusive.
... Studies have shown that the young females, go to bed earlier than male but were more likely to be disturbed by nightmares or awaken by little noise [22,23] which could result to manifestation of psychological symptoms over a prolonged period. These differences can be influenced by certain life factors such as age differences as observed in a wide cohort study [24], seasonal changes [25], family and next day activities [26]. ...
Studies have established the crucial role of sleep among the students which plays a significant role in their mood. This study aimed to examine the mood disorders and sleep quality among undergraduate students at the University of Georgia (UG) and comparison between students’ nationality.This cross-sectional study was a self-reported questionnaire comprised of demographics including age, gender, year of study, current location, lifestyle data (Exercise and smoking), the Depression, Anxiety, and Stress Scale (DAS21) and the Pittsburgh Sleep Quality Index (PSQI). We performed a descriptive analysis, and the Chi-square was statistically significant at p<0.05. The prevalence was at a 95% confidence interval (95% CI) as multivariate analysis examined the multicollinearity. The female students were most of the respondents, below the age of 20 years. The student's mean age was 20.20 (SD± 3.0). DAS report presented 72.7% of students with depressive symptoms, 77.8% with anxiety symptoms, and 62.2% had stress. Georgian students were more at risk of having depressive complaints (95% Cl[1.567-3.788]), anxiety (95% Cl[1.612-4.285]), and stress symptoms (95% Cl[1.743-3.831]). There was a strong relationship between the students who experienced poor sleeping patterns and depressive complaints (aOR 0.10). The students who were smokers (aOR 0.39) were more likely to report anxiety symptoms than the students that do not exercise (aOR 1.68). It was observed that students with depressive symptoms, anxiety, and complaints of stress had a significantly high risk of poor sleep quality. Further studies are recommended to curb psychological symptoms of mood changes in association with sleep disorders among students.
... The sleep architecture of insomnia is marked by prolonged sleep latency and strongly reduced TST, but the perception of reduced sleep tends to be some more severe than PSG data indicates, likely/possibly due to an increase of "micro-arousals" and alpha wave intrusion (Erman, 2001). Studies investigating the seasonality of insomnia either find no changes between seasons (Itani et al., 2016), or an increase of insomnia in winter (Husby and Lingjaerde, 1990;Friborg et al., 2012). The fact that the dataset shows a seasonal difference, as opposed to the expected changes, could indicate that these changes may be even greater if generalized to a healthy population. ...
While short-term effects of artificial light on human sleep are increasingly being studied, reports on long-term effects induced by season are scarce. Assessments of subjective sleep length over the year suggest a substantially longer sleep period during winter. Our retrospective study aimed to investigate seasonal variation in objective sleep measures in a cohort of patients living in an urban environment. In 2019, three-night polysomnography was performed on 292 patients with neuropsychiatric sleep disturbances. Measures of the diagnostic second nights were averaged per month and analyzed over the year. Patients were advised to sleep “as usual” including timing, except alarm clocks were not allowed. Exclusion criteria: administration of psychotropic agents known to influence sleep (N = 96), REM-sleep latency > 120 min (N = 5), technical failure (N = 3). Included were 188 patients: [46.6 ± 15.9 years (mean ± SD); range 17–81 years; 52% female]; most common sleep-related diagnoses: insomnia (N = 108), depression (N = 59) and sleep-related breathing disorders (N = 52). Analyses showed: 1. total sleep time (TST) longer during winter than summer (up to 60 min; not significant); 2. REM-sleep latency shorter during autumn than spring (about 25 min, p = 0.010); 3. REM-sleep longer during winter than spring (about 30 min, p = 0.009, 5% of TST, p = 0.011); 4. slow-wave-sleep stable winter to summer (about 60–70 min) with 30–50 min shorter during autumn (only significant as % of TST, 10% decrease, p = 0.017). Data suggest seasonal variation in sleep architecture even when living in an urban environment in patients with disturbed sleep. If replicated in a healthy population, this would provide first evidence for a need to adjust sleep habits to season.
... Therefore, normal short napping in summer which was 13 min longer than in winter may contribute to good sleep quality in summer. Our results are in agreement with other epidemiological studies which reported significantly poor sleep quality during the winter months in Northern European countries [13,15,30,31]. This alignment of results may be linked to temperature differences in addition to the sunset and sunrise differences between Oman and European countries. ...
Purpose
To describe the effect of seasonal variations on sleep patterns in a hot climate Arab region.
Methods
This is a cross-sectional study that included healthy Omani subjects of both genders between ages 18 and 59 years. Data for sleep pattern identification in summer and winter were collected from participants using an actigraphy wristband.
Results
Among 321 participants, in summer seasons, a polyphasic sleep pattern (40%) prevailed over other sleep patterns (P < 0.001). While in the winter season, monophasic sleep (31%) was the dominant pattern (P < 0.001). Subjects slept longer during the winter seasons with total hours of sleep during the day 48 min longer than in the summer, though the difference was not statistically significant (P > 0.05), while siesta duration in the summer was significantly longer (13 min, P < 0.01). In summer, the sleep quality was good (PSQI ≤ 5); however, it was poor (PSQI > 5) in winter (P < 0.05). Night sleep duration, daytime sleepiness, and sleep latency were not statistically different between the summer and winter seasons.
Conclusion
Sleep patterns may be influenced by seasonal changes. A polyphasic sleep pattern prevailed in summer while a monophasic pattern was the predominant sleep pattern in winter. In summer, the sleep quality was good and the siesta duration was longer compared to the winter.
... person must sleep well to feel happy during the day (Sadock, Flaherty, & Sadock, 2011). Insomnia is a general health disorder associated with occupational problems, interpersonal problems, driving accidents, educational problems, difficulty working night shifts, and anxiety (Bélanger, Morin, Langlois, & Ladouceur, 2004;Husby & Lingjaerde, 1990;Lader, 1999;Okada et al., 2000). According to studies, insomnia may develop at any age, although it is more common in aging (Friedman, 2006). ...
Introduction: Lack of high-quality sleep causes serious side effects like anxiety and changes in plasma concentration of oxalate. The current study aimed to investigate the impact of local extremely low frequency magnetic fields (ELF-MFs) on inducing sleep (sleepiness) and anxiety in male rats. Methods: In this experimental study, 40 male rats were allocated in four groups (n=10). The ELF-MFs exposure (0, 10 and 18 Hz) was applied with intensity 200µT for three days (10 min/day). Sham-treated animal did not receive ELF-MF. Serum level of oxalic acid (OA) and sleepiness were measured both before first and after last exposure to ELF-MF or sham. Anxiety, sleepiness and OA were measured by using elevated plus maze, open-field test (OFT) and ELISA test, respectively. Results: Comparison of oxalate levels between before and after exposure to ELF-MF revealed that ELF-MF (10 Hz) decreased the serum level of oxalate (p<0.05). Comparison of the percent of open:closed arm entry (in elevated plus maze) between before and after exposure to ELF-MF revealed significant differences. Also, frequency, velocity and distance moved were decreased in the open-field test. Conclusion: Results of the present study demonstrated that ELF-MF with short time exposure may modulate the metabolism of OA and may modulate anxiety-like behavior or kind of induction of sleepiness in male rats.
... However, there are also conflicting data. Several observational studies conducted in Norway found that insomnia symptoms and daytime impairment are more prevalent during winter than summer (Husby & Lingjaerde, 1990;Johnsen et al., 2012;Pallesen et al., 2001). It must also be acknowledged that several studies did not find seasonal variations in sleep characteristics (Johnsen et al., 2013;Sivertsen, Friborg, Pallesen, Vedaa, & Hopstock, 2020;Sivertsen et al., ,2011). ...
Subjective sleep reports are widely used research tools in epidemiology. Whether sleep reports can differ between seasons is less clear. Using multivariable binary or multinomial logistic regression analyses, in the present Swedish cross-sectional two-centre cohort study (N = 19,254; mean age 61 years), we found that participants surveyed during the summer (June–August) were more likely to report short sleep duration (defined as ≤ 6 hr) compared with those interviewed during the autumn (odds ratio [95% confidence interval] = 1.14 [1.04–1.25]). Individuals interviewed in the winter (December−February) were less likely to report early awakenings compared with participants surveyed in the autumn (September−November; odds ratio [95% confidence interval] = 0.85 [0.75–0.96]). Complaints of difficulties in falling asleep and disturbed sleep were less common among participants interviewed during spring (March–May) compared with those interviewed during the autumn (odds ratio [95% confidence interval] = 0.86 [0.74–0.99] and 0.88 [0.79–0.98], respectively). No seasonal variations in reports of long sleep, difficulty maintaining sleep, or feeling not rested after sleep were observed. Additional subgroup analysis revealed that summer participants were more likely to report short sleep duration and early morning awakenings than individuals surveyed in winter. In conclusion, this Swedish study indicates that self-reported sleep characteristics may vary across seasons. Further studies are needed to confirm our findings.
... The healthy participants also suffered great fatigue at high atmospheric temperatures (44 °C) and humidity (80%) [3]. Previous Nordic epidemiology reported that sleep quality is poor in summer [4] and in the middle of winter [5,6]. Meanwhile, in temperate zones, the sleep duration of the residents is longer in winter than in summer [7][8][9]. ...
Thermal comfort is crucial in satisfaction and maintaining quality sleep for occupants. In this study, we investigated the comfort temperature in the bedroom at night and sleep quality for Indonesian students during summer and winter. Eighteen male Indonesian students aged 29 ± 4 years participated in this study. The participants had stayed in Japan for about six months. We evaluated the sleep parameters using actigraphy performed during summer and winter. All participants completed the survey regarding thermal sensation, physical conditions, and subjective sleepiness before sleep. The temperature and relative humidity of participants’ bedrooms were also measured. We found that the duration on the bed during winter was significantly longer than that during summer. However, sleeping efficiency during winter was significantly worse than that during summer. The bedroom temperature of the participants was in the range of comfort temperature in Indonesia. With the average bedroom air temperature of 22.2 °C, most of the participants still preferred “warm” and felt “slightly comfortable” during winter. The average comfort temperature each season calculated using the Griffiths method was 28.1 °C during summer and 23.5 °C during winter. In conclusion, differences in adaptive action affect bedroom thermal conditions. Furthermore, habits encourage the sleep performance of Indonesian students.
... Finally, the data was obtained from February to April in a geographical region with substantial seasonal differences in daylight hours, which may have had an effect on sleep and its timing. Indeed, studies from high latitudes have found some sleep phase delay, with a slight increase in insomnia problems and fatigue during the winter as compared to the summer season (Husby and Lingjaerde, 1990;Johnsen et al., 2012Johnsen et al., , 2013Friborg et al., 2014). However, results from a recent population-based study in Northern Norway found little evidence of seasonal variations in sleep (Sivertsen et al., 2020), even though the amount of daylight varied from 0 to 24 h across the year. ...
Objective
Numerous epidemiological studies have been conducted to examine the prevalence and comorbidities of insomnia and document sleep duration, but a common limitation in many studies is the lack of use of agreed-upon definitions of insomnia, as well as insufficient statistical power to examine comorbid mental and physical disorders/conditions.
Aim
To examine the prevalence of insomnia operationalized according to formal DSM-5 criteria and differences in mean sleep duration across a wide range of mental and physical disorders, examining men and women separately.
Materials and Methods
Data stem from the SHoT study (Students’ Health and Wellbeing Study), a national survey of all college and university students in Norway. In all, 162,512 students aged 18–35 received an invitation to participate, of whom 50,054 students completed the internet-based survey (attendance rate: 30.8%). Insomnia was defined according to the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria and sleep duration was calculated separately for weekdays and weekends. Self-reported mental and physical disorders/conditions were assessed using a pre-defined list modified to fit this age group. Pearson chi-squared tests were used to examine the prevalence of insomnia across the various mental and physical disorders/conditions in men and women separately, and log-link binomial regression analysis were used to calculate effect-sizes, adjusting for age.
Results
The prevalence of insomnia in both sexes was significantly higher across all mental disorders compared with a healthy reference group. Among females, the prevalence of insomnia ranged from 61.3% for comorbid depression (adj. RR = 2.49, 95% CI: 2.40) to 83.3% for comorbid schizophrenia (adj. RR = 3.37, 95% CI: 2.61–4.35). For males, the insomnia prevalence ranged from 32.3% for comorbid autism/Asperger (adj. RR = 2.02, 95% CI: 1.39–2.92) to 74.2% for comorbid eating disorder (adj. RR = 4.51, 95% CI: 3.87–5.27). The overall prevalence of insomnia was also significantly higher across most physical conditions compared with the healthy reference group, although generally lower compared to the mental disorders. For females, the insomnia prevalence ranged from 25% for comorbid multiple sclerosis (not significant) to 65.4% for comorbid chronic fatigue syndrome/ME (adj. RR = 2.66, 95% CI: 2.44–2.89). For males, the insomnia prevalence ranged from 20% for both comorbid cancer and diabetes (not significant) to 74.2% for comorbid fibromyalgia (adj. RR = 4.35, 95% CI: 2.96–6.39). Similar patterns were observed for sleep duration, with a significantly shorter sleep duration for across many physical disorders, but especially mental disorders.
Conclusion
Insomnia and short sleep duration are strongly associated with a range of different disorders and conditions. Insomnia is most strongly associated with mental disorders, and physical conditions characterized by some level of psychological or psychosomatic properties.
... In human adults, various sex differences in sleep have been noted (Carrier et al., 2017). For instance, women report having more frequent insomnia symptoms, reduced sleep quality, and difficulty staying asleep compared to men (Husby and Lingjaerde, 1990;Li et al., 2002;Lindberg et al., 1997;Mong et al., 2011). Paradoxically, objective sleep measures show that compared to men, women have longer total sleep time (Bixler et al., 2009;Redline et al., 2004;Ursin et al., 2005), and higher power in the high sigma range (14-16 Hz) during NREMS (Carrier et al., 2001;Mongrain et al., 2005). ...
Sleep is a vital part of our lives as it is required to maintain health and optimal cognition. In humans, sex differences are relatively well-established for many sleep phenotypes. However, precise differences in sleep phenotypes between male and female rodents are less documented. The main goal of this article is to review sex differences in sleep architecture and electroencephalographic (EEG) activity during wakefulness and sleep in rodents. The effects of acute sleep deprivation on sleep duration and EEG activity in male and female rodents will also be covered, in addition to sex differences in specific circadian phenotypes. When possible, the contribution of the female estrous cycle to the observed differences between males and females will be described. In general, male rodents spend more time in non-rapid eye movement sleep (NREMS) in comparison to females, while other differences between sexes in sleep phenotypes are species- and estrous cycle phase-dependent. Altogether, the review illustrates the need for a sex-based perspective in basic sleep and circadian research, including the consideration of sex chromosomes and gonadal hormones in sleep and circadian phenotypes.
... In countries at northern latitudes such as Canada, seasonality is known to exacerbate depressive symptoms and affect sleep quality: the coldest and darkest months are associated with higher rates of depression 69 and insomnia. [70][71][72] This effect is more pronounced in older people than in other age groups. 73 The present study was probably subject to this seasonality affect. ...
Purpose
The objective of this exploratory study was to evaluate the effects of a brief intervention intended to optimize the sleep environment in older people living in the community and to examine the way these effects change over time.
Methods
The sample was made up of 44 participants (19 men and 25 women) aged 65–85 years, with a mean age of 71.4. The intervention consisted in a group training session that covered the reasons for and ways to (“why” and “how”) optimize a sleep environment. It comprises six themes: air quality and odors, luminosity, noises and sounds, comfort of the mattress, comfort of the pillow, and temperature. Participants completed a set of questionnaires before the intervention, and one month and four months later.
Results
Four months after the intervention, the replies to the questionnaires showed that the participants experienced reduced severity of insomnia, sleep latency and anxiety. The subjective quality of the participants’ sleep along with their sleep efficacy also increased significantly during the same period.
Conclusion
A brief intervention intended to optimize the sleep environment appears promising as an addition or alternative to the two other sleep improvement options generally offered to older people: medication and cognitive behavioral therapy.
... The high rate of insomnia observed in the current study is noteworthy, and far higher than previous prevalence estimates adhering to common diagnostic criteria (Ohayon, 2002;Pallesen et al., 2014;Uhlig et al., 2014). Whether this discrepancy reflects an actual (Friborg, Rosenvinge, Wynn, & Gradisar, 2014;Husby & Lingjaerde, 1990;Johnsen, Wynn, Allebrandt, & Bratlid, 2013;Johnsen, Wynn, & Bratlid, 2012). However, the seasonal flow in insomnia seems to be in the weak-to-moderate range, whereas seasonal changes in fatigue are generally more pronounced (Friborg et al., 2014;Friborg, Sundby, & Rognmo, 2018). ...
Epidemiological studies assessing adult sleep duration have yielded inconsistent findings and there are still large variations in estimation of insomnia prevalence according to the most recent diagnostic criteria. Our objective was to describe sleep patterns in a large population of middle‐aged and older adults, by employing accurate measures of both sleep duration and insomnia. Data stem from the Tromsø Study (2015–2016), an ongoing population‐based study in northern Norway comprising citizens aged 40 years and older (n = 21,083, attendance = 64.7%). Sleep parameters were reported separately for weekdays and weekends and included bedtime, rise time, sleep latency and total sleep time. Insomnia was defined according to recent diagnostic criteria (International Classification of Sleep Disorders; ICSD‐3). The results show that 20% (95% confidence interval,19.4–20.6) fulfilled the inclusion criteria for insomnia. The prevalence was especially high among women (25%), for whom the prevalence also increased with age. For men, the prevalence was around 15% across all age groups. In all, 42% of the women reported sleeping <7 hr (mean sleep duration of 7:07 hr), whereas the corresponding proportion among males was 52% (mean sleep duration of 6:55 hr). We conclude that the proportion of middle‐aged and older adults not getting the recommended amount of sleep is worryingly high, as is also the observed prevalence of insomnia. This warrants attention as a public health problem in this population.
... Sleep disturbances, especially insomnia, are frequently observed in healthy individuals. The prevalence of insomnia has been reported to range between 20% and 35% in the general population and between 10% and 52% in the elderly 11,18) . A high prevalence of insomnia has also been observed in patients with neurological diseases. ...
Objective:
We investigated the effect of hypnotics on sleep quality, cognitive function, and depressive mood in patients with insomnia following brain tumor resection.
Methods:
From patients who underwent brain tumor resection, we recruited 10 patients with insomnia who received hypnotics for more than 1 week during a 3-week follow-up period (insomnia group). We also recruited 12 control patients with brain tumors but without insomnia (control group). We evaluated sleep quality at baseline and 3 weeks later using the Insomnia Severity Index (ISI), the Pittsburgh Sleep Quality Index (PSQI), the Stanford Sleepiness Scale (SSS), and the Epworth Sleepiness Scale (ESS) and investigated cognitive function and depression using the Computerized Neuropsychological Test and the Beck Depression Inventory (BDI).
Results:
At baseline, SSS, ISI, PSQI, and BDI scores were significantly higher and visual continuous performance test (VCPT) and auditory continuous performance test (ACPT) scores were significantly lower in the insomnia than in the control group. Three weeks later, the patients who had received hypnotics had significantly higher ISI, PSQI, ESS, VCPT, ACPT, visual span forward and backward, and visual recognition test scores, and significantly lower BDI scores.
Conclusion:
Quality of sleep in patients with insomnia following brain tumor resection was initially poor but improved significantly after taking hypnotic medication. Further, the hypnotic medications appeared to contribute to the amelioration of cognitive impairments and depressive moods in patients who previously underwent brain tumor resection. We thus recommend the use of hypnotics for patients with brain tumors with insomnia.
... However the predilection of the female sex to insomnia has also been seen among younger children [50][51][52][53] . Further these results are seen uniformly in the most studies around the world [54][55][56][57][58][59] . Studies from India by Suri et al found insomnia to more common among females (23.6: 32.5% among male and females respectively in adult and 50.0: 63.5% among males & females respectively among the elderly). ...
... Epidemiological studies in Northern European countries have demonstrated that insomnia is more prevalent in winter [15][16][17], although conflicting results have been reported [32]. The mechanisms of mid-winter insomnia in this region remain unclear, but it has been suggested that mid-winter insomnia is a reflection of phase delay of the sleep-wake rhythm caused by a lack of daylight [33]. ...
Background
A scientific understanding of the effects of seasonal changes on sleep duration and sleep problems such as insomnia and hypersomnia has yet to be elucidated; however, such an understanding could aid the establishment of an optimal sleep hygiene program to treat such problems.
Methods
We investigated the effects of seasonal changes on sleep duration and sleep problems in Japanese community residents. Data on 1,388 individuals aged 15–89 years who participated in the Survey of Seasonal Variations in Food Intakes conducted by the National Institute of Health and Nutrition of Japan (2004–2007) were analyzed. Participants completed a questionnaire including items on sleep duration and sleep problems (difficulty initiating sleep [DIS], difficulty maintaining sleep [DMS]/early morning awakening [EMA], and excessive daytime sleepiness [EDS]). Data were prospectively collected at four time points (spring, summer, fall, and winter).
Results
Seasonal changes in sleep duration were found, with the longest in winter and the shortest in summer (winter–summer difference: 0.19 h). The seasonality of sleep duration was influenced by age, sex, and residential area. In terms of age, seasonal changes in sleep duration were found in the middle and old age groups, but not in the young age group. Seasonal changes in the frequencies of sleep problems were found for some items in the young age group (DMS/EMA and EDS) and middle age group (DIS and DMS/EMA); however, no such changes were observed in the old age group.
Conclusion
Seasonal effects on sleep and sleep problems were found in Japanese community residents, but these varied between age groups. Furthermore, seasonal changes in sleep duration were influenced by sex and residential area.
... The prevalence of insomnia is somewhat difficult to achieve due to methodological caveats, such as the definition of insomnia, the diagnostic criteria, sampling biases among studies and source population 20 . Even so, it is estimated that about 12-40% percent of all women reports insomnia-compatible symptoms [21][22][23][24][25][26][27][28][29] . In all cases, women are twice as likely to experience insomnia throughout their lifespan compared to men 30 , and the female to male prevalence ratio of insomnia is approximately 1.5/1 31 . ...
Due to the changes that took place since the 1970s, women have achieved important socioeconomic positions. Many tasks, including domestic and familiar ones, continue to be under women's responsibility, which leads to an overload work. Additionally, the female organism has its peculiarities due to hormonal changes. Adding all these factors up, women seem to be more vulnerable to stressing factors and consequently, might be prone to present several health problems. Within this scenario, one can point out insomnia as a highly prevalent disease among women, directly affecting performance and quality of life. Progesterone has an important effect over sleep, acting both as a hypnogenic and as a respiratory stimulant. Hormonal contraceptives are largely recognized among the modern society women; however, little is known about the effects of these drugs on sleep. This proposal hypothesizes that the use of hormonal contraceptives, mainly those based on progestagens could be a new therapeutic element for the treatment of insomnia and one more tool to be used to improve women's sleep pattern and quality of life. © 2018 Brazilian Association of Sleep and Latin American Federation of Sleep Societies. All rights reserved.
... Moreover, the studies of the effects of season on rate of sleeping problems are mostly limited to populations from Scandinavian countries. These effects were found to be significant in several Norwegian studies [2][3][4][5][6] , but the significance of these effects was not confirmed in one of the largest Norwegian studies 7 . In one more Norwegian study significant seasonality of sleeping problems was found only in a specific group of respondents experiencing seasonal variation in their well-being, energy, sleep length, socialization, body weight, etc. 8 . ...
... Moreover, the studies of the effects of season on rate of sleeping problems are mostly limited to populations from Scandinavian countries. These effects were found to be significant in several Norwegian studies [2][3][4][5][6] , but the significance of these effects was not confirmed in one of the largest Norwegian studies 7 . In one more Norwegian study significant seasonality of sleeping problems was found only in a specific group of respondents experiencing seasonal variation in their well-being, energy, sleep length, socialization, body weight, etc. 8 . ...
Compared to literature on seasonal variation in mood and
well-being, reports on seasonality of trouble sleeping are scarce and contradictive. To
extend geography of such reports on example of people naturally exposed to
high-amplitude annual variation in daylength and/or temperature. Participants were the
residents of Turkmenia, West Siberia, South and North Yakutia, Chukotka, and Alaska.
Health and sleep-wake adaptabilities, month-to-month variation in sleeping problems,
well-being and behaviors were self-assessed. More than a half of 2398 respondents
acknowledged seasonality of sleeping problems. Four of the assessed sleeping problems
demonstrated three different patterns of seasonal variation. Rate of the problems
significantly increased in winter months with long nights and cold days (daytime
sleepiness and difficulties falling and staying asleep) as well as in summer months with
either long days (premature awakening and difficulties falling and staying asleep) or
hot nights and days (all 4 sleeping problems). Individual differences between
respondents in pattern and level of seasonality of sleeping problems were significantly
associated with differences in several other domains of individual variation, such as
gender, age, ethnicity, physical health, morning-evening preference, sleep quality, and
adaptability of the sleep-wake cycle. These results have practical relevance to
understanding of the roles playing by natural environmental factors in seasonality of
sleeping problems as well as to research on prevalence of sleep disorders and methods of
their prevention and treatment in regions with large seasonal differences in temperature
and daylength.
... However the predilection of the female sex to insomnia has also been seen among younger children [50][51][52][53] . Further these results are seen uniformly in the most studies around the world [54][55][56][57][58][59] . Studies from India by Suri et al found insomnia to more common among females (23.6: 32.5% among male and females respectively in adult and 50.0: 63.5% among males & females respectively among the elderly). ...
Insomnia is an extremely common disorder. The prevalence of insomnia in a study depends on the criteria's selected for determining the prevalence. It is well known that several factors like gender, age, psychiatric disorders among several others are risk factors for insomnia. The stress of modern urban life adds to the factors responsible for an increase in the prevalence. In addition several co-morbid factors can have a significant effect on the prevalence of insomnia. However,what is important is the effect insomnia has on the quality of life of the individual, its social implications like increased loss of work days, accidents, family disorders and the economic impact of this rather common disorder. This review summarizes the burden of this problem in the Indian context.
... Bij hamsters induceert een beperking in de blootstelling aan licht een verminderde productie van vasopressine en vasoactive intestinal polypeptide in de scn. In het arctische gebied treedt bovenop de niet-seizoensgebonden insomnie bij 9% van de mannen en 17,6% van de vrouwen de zogenaamde midwinter insomnia op (Husby & Lingjaerde 1990); het risico neemt toe met leeftijd. Driekwart van de patiënten met retinitis pigmentosa vertoont slaapstoornissen. ...
Nearly every physiological process has a circadian rhythm lasting about 24 hours. In the elderly and particularly in those with dementia these rhythms become unstable and have a reduced amplitude. This review article describes the fundamental changes that occur in the suprachiasmatic nucleus, which is the centre of the circadian system, and explains how these changes interfere with the health, sleep, mood and cognitive performance of the elderly and the elderly with dementia and affect their well-being. Apparently, the circadian system of the elderly receives fewer stimuli since the elderly are less requently exposed to bright light, produce less melatonin, engage in less physical activity and are less affected by somatosensory and thermoreceptive stimuli. The review article focuses on the problems arising from reduced exposure to bright light. That seems to gradually inactivate the SCN neurons. It has been shown that exposure of aged animals to extra light reactivates their neurons and revitalises their poorly functioning circadian systems. In the case of healthy old people and old people with dementia extra light appears to relieve the above mentioned negative effects of their malfunctioning circadian systems. These findings indicate the preservation of the plasticity of the circadian rhythm in the elderly. They also emphasise the need for longitudinal placebo-controlled randomised investigations into the benefits that daily supplements of bright light can bestow in the elderly in terms of improved health and well-being.
... Por último, el diseño transversal y el método de muestreo no aleatorio en dos días consecutivos de trabajo semanales en las clínicas de atención primaria impiden el cálculo de la prevalencia y la adecuada valoración del patrón estacional del insomnio que ha sido descrito en otras poblaciones. 14,19 Consideramos, sin embargo, que como todo estudio transversal, este trabajo puede ser el punto de partida para futuras exploraciones prospectivas de la epidemiología del insomnio y sus consecuencias en México. Dentro del contexto de estas limitaciones, en este estudio encontramos que el insomnio tiene una prevalencia alta en la población de pacientes que acuden a consulta de medicina general en México, siendo la coexistencia de los cuatro subtipos de insomnio la combinación más frecuente de síntomas. ...
INTRODUCTION: The assessment of the deleterious effects of insomnia on daytime functioning is an essential part of the epidemiology of insomnia. OBJECTIVE: To describe the demographic characteristics, symptoms of insomnia and daytime consequences in Mexican patients enrolled in the international study EQUINOX. METHODS: The EQUINOX descriptive study originally included outpatients pertaining to 10 countries. In this report we analyzed data of patients attending primary care facilities in Mexico, with different reasons for medical consultation. We interviewed all patients for two consecutive days of each workweek. Those identified with insomnia received a standardized questionnaire that included anthropometric and socio-demographic characteristics of insomnia, daytime consequences of insomnia and type of intervention to treat it. RESULTS: We evaluated 3,021 Mexicans, with a frequency of 62.3% insomnia. Difficulty initiating sleep was present in 1,135 patients (82.4%), difficulty maintaining sleep in 1,108 (80.4%), early morning awakenings in 983 (71.3%) and restless sleep in 1,144 patients (83%). The social, emotional, and professional functioning was affected in 75% of patients and in 25% this involvement was severe. CONCLUSIONS: Insomnia is a very common sleep disorder in Mexicans. Primary care physicians play a key role in the identification, treatment and monitoring of insomnia and its daytime consequences.
... To account for why such a large gender difference has been reported, a few hypotheses have been offered. For example, the entrainment of the sleep-wake cycle may be more dependent on the effect of daylight in women (Husby & Lingjaerde, 1990). ...
Historically, research on Seasonal Affective Disorder (SAD) has focused primarily on physiological hypotheses regarding etiology and maintenance. Recently research has also begun to investigate psychological and psychophysiological correlates of the disorder. The relation of activity level to SAD episode development, maintenance and recurrence, however, has not been investigated thoroughly. In this study, relationships between self-report (i.e., questionnaires and logs) and objective (i.e., actigraphy) measurements of activity and SAD were investigated. Also, the relationship between quantitative (i.e., number of activities or activity counts) and qualitative (i.e., activity enjoyment) aspects of activity and SAD were examined. It was hypothesized that individuals with SAD would experience activity levels that differed from those of controls. Various components of activity were examined (e.g., daytime activity, activity during sleep). In addition, the importance of activity enjoyment was also investigated. Individuals with a history of SAD (SAD-HX), individuals with a diagnosis of major depression (MDD), and controls were each assessed twice: in the winter and subsequent summer, or the summer and subsequent winter. At each measurement occasion, general depression symptoms, automatic negative thoughts, attitudes towards the seasons, motor activity levels, activity frequency and enjoyment of activities were assessed. In general, the results of this study supported the hypothesis that certain aspects of the activity patterns of individuals with a SAD-HX differ from those of controls. Although individuals with a SAD-HX did not differ from controls in objectively measured daytime activity, participants with a SAD-HX exhibited disrupted nocturnal activity patterns compared to controls. In addition, individuals with a SAD-HX differed from controls with regard to self-reported activities. Participants with a SAD-HX reported participating in fewer activities and enjoying these activities less than controls. The current study provides continued support for the contribution of cognitive factors that may relate to SAD episode recurrence and severity. Individuals with a SAD-HX exhibited patterns of negative thinking and styles of responding similar to individuals with major depression even during asymptomatic months. Implications of these findings for SAD research and treatment in general and for future SAD research are discussed.
... In fact, a growing body of evidence suggests that poor sleep increases inflammation that may contribute to undesired cardiovascular consequences (12). Different studies have shown that gender may change the link between sleep quality and inflammatory biomarkers (13)(14)(15)(16). In one study, sleep quality predicted 5-year changes in inflammatory biomarkers in women but not men (12). ...
This study aimed to investigate the interaction between gender and other socio-economic characteristics on sleep quality of the patients with Coronary Artery Disease (CAD).
This cross sectional study was conducted on 717 patients with CAD. The socio- economic status (education level, income, marital status, and place of residence) was considered as the independent variable. Besides, the study outcome was the quality of sleep which was measured using Pittsburgh Sleep Quality Index (PSQI). Gender was considered as a possible effect modifier. Two-way ANOVA was used to evaluate the interaction between gender and socio-economic factors on sleep quality. As defined by Baron and Kenny, moderator was defined as a variable that affected the direction or magnitude of the association of interest.
Female gender, low education level, and low income were predictive of poor sleep quality. Among female (10.0 ± 4.3 vs. 7.6 ± 5.0, P < 0.05), but not male patients (6.7 ± 4.2 vs. 7.0 ± 4.2, P > 0.05), low education was associated with poor sleep quality. Also, among female (10.0 ± 4.3 vs. 5.7 ± 2.5, P < 0.05), but not male patients (7.0 ± 4.2 vs. 6.0 ± 3.8, P > 0.05), low income was predictive of poor sleep quality. Gender did not modify the effect of other socio-economic factors on sleep quality.
Among female but not male patients with CAD, low education and income were associated with poor sleep quality. This information helps us better understand the mechanisms behind the poor sleep quality of the female patients with CAD. This is important because poor sleep is a prognostic factor among the CAD patients.
... Although sleep disturbances are common both in women and men across all age ranges, the literature supports female dominance [1][2][3]. Women are 1.3-1.6 times more likely than men to report sleep disturbances [4][5][6][7]. Biologic vulnerability precipitating or aggravating sleep disturbances may be associated with female reproductive phases, such as menstruation cycle [8,9] puerperium [8] or menopause [8,10] and comorbid conditions, sociological and psychological factors, and higher rates of depression and anxiety. Disturbed sleep, in both genders, is often linked with increased work absenteeism, disability and health care costs [11][12][13] and has been shown to predict morbidity and mortality [14][15][16][17]. ...
To evaluate the prevalence of sleep disturbances and the contributing factors in middle-aged women.
In a cross-sectional design of the long-term, prospective follow-up study project of 1278 families from a random population sample, the mothers of 15 year-olds were asked to fill in a questionnaire about sleep, health, health related quality of life, and health behavior.
Quality of sleep was reported by 32% of women as good, 43% quite good, 12% average, 10% quite poor and 3% as poor. The most frequent sleep disturbance was awakenings in the night, which 60% of the women experienced at least once a week. Difficulty falling asleep and waking too early in the morning were reported as a weekly occurrence by 16% and 20%, respectively. Morning sleepiness was experienced by 42% and daytime sleepiness by 32%. Chronic diseases and use of medications was associated with various sleep disturbances. Both somatic and mental symptoms increased the risk for sleep disturbances.
Almost one-quarter of middle-aged women is dissatisfied with their quality of sleep. Women who have chronic disease or use of medications for basic diseases often suffer from sleep disturbance, which is also associated with the health related quality of life. Further analysis of the risk factors is needed to improve the sleep health of middle-aged women.
... In fact, a growing body of evidence suggests that poor sleep increases inflammation that may contribute to undesired cardiovascular consequences (12). Different studies have shown that gender may change the link between sleep quality and inflammatory biomarkers (13)(14)(15)(16). In one study, sleep quality predicted 5-year changes in inflammatory biomarkers in women but not men (12). ...
Background: This study aimed to investigate the interaction between gender and other
socio-economic characteristics on sleep quality of the patients with Coronary Artery
Disease (CAD).
Methods: This cross sectional study was conducted on 717 patients with CAD. The socioeconomic
status (education level, income, marital status, and place of residence) was
considered as the independent variable. Besides, the study outcome was the quality of
sleep which was measured using Pittsburgh Sleep Quality Index (PSQI). Gender was
considered as a possible effect modifier. Two-way ANOVA was used to evaluate the
interaction between gender and socio-economic factors on sleep quality. As defined by
Baron and Kenny, moderator was defined as a variable that affected the direction or
magnitude of the association of interest.
Results: Female gender, low education level, and low income were predictive of poor
sleep quality. Among female (10.0 ± 4.3 vs. 7.6 ± 5.0, P < 0.05), but not male patients (6.7
± 4.2 vs. 7.0 ± 4.2, P > 0.05), low education was associated with poor sleep quality. Also,
among female (10.0 ± 4.3 vs. 5.7 ± 2.5, P < 0.05), but not male patients (7.0 ± 4.2 vs. 6.0 ±
3.8, P > 0.05), low income was predictive of poor sleep quality. Gender did not modify the
effect of other socio-economic factors on sleep quality.
Conclusions: Among female but not male patients with CAD, low education and income
were associated with poor sleep quality. This information helps us better understand
the mechanisms behind the poor sleep quality of the female patients with CAD. This is
important because poor sleep is a prognostic factor among the CAD patients.
... Bij hamsters induceert een beperking in de blootstelling aan licht een verminderde productie van vasopressine en vasoactive intestinal polypeptide in de scn. In het arctische gebied treedt bovenop de niet-seizoensgebonden insomnie bij 9% van de mannen en 17,6% van de vrouwen de zogenaamde midwinter insomnia op (Husby & Lingjaerde 1990); het risico neemt toe met leeftijd. Driekwart van de patiënten met retinitis pigmentosa vertoont slaapstoornissen. ...
Alzheimer’s disease (AD) affects more women than men, with women throughout the menopausal transition potentially being the most under researched and at-risk group. Sleep disruptions, which are an established risk factor for AD, increase in prevalence with normal aging and are exacerbated in women during menopause. Sex differences showing more disrupted sleep patterns and increased AD pathology in women and female animal models have been established in literature, with much emphasis placed on loss of circulating gonadal hormones with age. Interestingly, increases in gonadotropins such as follicle stimulating hormone are emerging to be a major contributor to AD pathogenesis and may also play a role in sleep disruption, perhaps in combination with other lesser studied hormones. Several sleep influencing regions of the brain appear to be affected early in AD progression and some may exhibit sexual dimorphisms that may contribute to increased sleep disruptions in women with age. Additionally, some of the most common sleep disorders, as well as multiple health conditions that impair sleep quality, are more prevalent and more severe in women. These conditions are often comorbid with AD and have bi-directional relationships that contribute synergistically to cognitive decline and neuropathology. The association during aging of increased sleep disruption and sleep disorders, dramatic hormonal changes during and after menopause, and increased AD pathology may be interacting and contributing factors that lead to the increased number of women living with AD.
Background
Delayed sleep–wake phase disorder (DSWPD) during adolescence has been linked to impaired health and poor functioning. However there is a dearth of knowledge about DSWPD in young adulthood. We seek to contribute knowledge on the prevalence and correlates of DSWPD in this age group.
Methods
Data were drawn from a 2018 national survey of students in higher education in Norway (the SHoT-study). All 162,512 fulltime students in Norway were invited to participate and 50,054 students (69.1% women) aged 18–35 years were included (response rate = 30.8%). DSWPD was assessed by self-report, and was operationalized according to the criteria for DSWPD in the most recent edition of the International Classification of Sleep Disorders. Correlates of DSWPD were examined by validated self-report instruments covering a wide range of demographic and health domains.
Results
The overall prevalence of DSWPD was 3.3%, and significantly higher in male (4.7%) than female (2.7%) students. DSWPD was associated with being single, having financial difficulties, having divorced parents, being overweight/obese, and physical inactivity. Students with DSWPD had more sleep problems during weekdays, and higher levels of somatic and mental health problems. Students with DSWPD also had an elevated risk of self-harm-related thoughts and behaviors as well as suicidality.
Conclusion
DSWPD remains a significant problem among young adults, and the high symptom load across health domains indicates that suggests a need for existing evidence-based approaches to be scaled for college students who present with DSWPD.
Seasonality is evident in several aspects of human health and behavior, whereas seasonality in chronic pain is less well studied. We examined seasonal variation in pain severity and pain dissemination, as well as in pain-associated conditions, such as sleep impairment, sleep timing, mental distress, fatigue and physical activity. We also examined if any of these associated conditions moderated the seasonality in pain. This prospective study was conducted in the subarctic municipality of Tromsø, Norway (69º North), on a sample of patients with chronic musculoskeletal pain (N = 56). Data were collected with self-report questionnaires and objective actigraphy measures (7 days) twice: winter and summer. Mixed linear regression models were fitted. A modest seasonality effect was observed in pain severity (highest in summer), but not in pain dissemination. Seasonality with increased physical activity and delayed sleep timing in the summer was also present. The remaining pain-associated self-report or objective measures indicated no seasonality. The season–pain association was not significantly moderated by any of the pain-associated conditions. Previous studies on healthy individuals residing in polar areas have suggested an opposite seasonal effect with delay of the sleep–wake rhythm in winter. Our results based on a clinical sample thus represent a novel finding that needs to be examined further with regard to seasonal circadian entrainment and alignment in pain populations. These results may have clinical value for the treatment of patients with musculoskeletal pain as seasonality may require seasonal adjustments of pain treatment strategies.
Objective:
Although reproductive function is influenced by season, few studies have evaluated seasonal effects on menopausal symptoms. We assessed the impact of season and proximity to the final menstrual period (FMP) on frequency of symptom reporting.
Methods:
In all, 955 participants in the Study of Women's Health Across the Nation recorded whether or not they had experienced menopausal symptoms on a monthly menstrual calendar over a 10-year period. We modeled the log-odds of presence of a given symptom each month using a logistic mixed-effects model, assuming a third-order polynomial before the FMP and a different third-order polynomial after the FMP. We assumed sine and cosine functions for month of the year.
Results:
Five to 10 years before the FMP, ∼20% of women reported hot flashes and night sweats, whereas ∼40% reported trouble sleeping. Prevalence rose ∼4 years before the FMP with a sharp jump in hot flash (∼60%) and night sweats (∼40%) prevalence coincident with the FMP. Peaks in hot flashes and trouble sleeping were observed in July with troughs in January. The peak and trough in night sweats occurred about 1 month earlier. Odds of hot flashes, night sweats, and trouble sleeping were 66%, 50%, and 24% greater, respectively, at the seasonal peak versus the seasonal minimum.
Conclusion:
Menopausal symptoms exhibit seasonal variation associated with the summer and winter equinoxes. Seasonal increases in night sweats precede increases in hot flashes. Prospectively recorded monthly symptom data demonstrate that hot flashes and night sweats increase notably coincident with the FMP. : Video Summary:http://links.lww.com/MENO/A476.
Seasonal changes in daylight are substantial in subarctic areas and are known to affect circadian sleep rhythms. We examined whether seasonality in cognitive performance also exists and to what extent seasonality in sleep moderates this relationship. In the city of Tromsø (Norway) at 69°N, 182 adolescents (36% male; mean age 16.8 years) participated in a prospective study. The cognitive measures included verbal and visual memory, verbal learning, psychomotor speed, and problem solving, whereas sleep and sleep-related problems were recorded via weekly sleep diaries and questionnaires. The results indicated no effect of season on any of the cognitive tests. Seasonality in sleep timing, insomnia, and fatigue were confirmed; however, these variables did not modify the null correlation between season and cognition. The lack of seasonality in cognition is a positive finding and serves to undermine myths about the burdens of living in subarctic areas with substantial seasonal changes in daylight.
This chapter briefly describes sleep and its impact on health in certain extreme situations in the environment (e.g., space travel, polar regions, mountain climbers at high altitude, deep-sea divers in hyperbaric atmosphere, and extremely hot climates in the tropics). There are limited but adequate data in the literature to make some tentative conclusions about the adverse effects of microgravity on sleep obtained from many space and simulated missions. There are valid scientific data to show hypoxemia due to a low barometric pressure at high altitude, causing periodic breathing and sleep dysfunction in unacclimatized mountain climbers. There are very limited data available to make a firm conclusion about polar and tropical insomnia and other sleep dysfunction.
Prevalence of insomnia is variable due to inconsistency in defining the syndrome. It can be seen with or without comorbid illnesses and is now recognized as a distinct clinical syndrome even when associated with an underlying medical or psychiatric disorder. It is more common in women and in people who do shift work. Insomnia is present worldwide but appears to be less common in Asians. Individuals who have an anxiety-prone personality and depression are more prone to develop insomnia. It can have a huge economic impact as insomnia sufferers place a significant economic burden on their employers and health care system. Insomnia may be a risk factor for development of depression, hypertension, diabetes, and coronary artery diseases.
Background:
This study was a nationwide epidemiological study of insomnia in Japan. It was conducted because very few studies on this topic have previously been performed for the general Japanese population.
Methods:
An interview survey on symptoms of insomnia (difficulty initiating sleep, difficulty maintaining sleep with difficulty resuming sleep, and early morning awakening with difficulty resuming sleep) and daytime dysfunction was conducted on the general nationwide population in the winter (February) and summer (August) of 2008. Data from 2614 participants who provided valid responses (age range 20-95 years, valid response rate 54.2%) were analyzed.
Results:
The prevalence of difficulty initiating sleep, difficulty maintaining sleep with difficulty resuming sleep, and early morning awakening with difficulty resuming sleep was 8.3%, 5.8%, and 5.8%, respectively, in men, and 11.0%, 8.1%, and 7.4%, respectively, in women. The prevalence of insomnia was 12.2% in men and 14.6% in women, and the prevalence of insomnia with daytime dysfunction was 3.2% in men and 4.2% in women. The results of logistic regression analyses indicated that the factors aggravating insomnia for men were unemployment and having mental health issues, and for women they were being aged ≥70 years, completing fewer years of schooling, and having mental health issues. Seasonality and regionality in association with insomnia were also examined, but no significant associations were found.
Conclusion:
In the present survey, insomnia was defined by using criteria that were closer to the clinical diagnostic criteria (eg, coexistence of both difficulty resuming sleep and daytime dysfunction was considered). Therefore, it is believed that the results of this study were representative of the clinical actuality of insomnia in Japan.
Objetivo: Evaluar la prevalencia de algunos problemas de sueño y de síntomas de trastornos de la conducta alimentaria (TCA), así como las posibles asociaciones entre ellos, en una población de mujeres jóvenes. Método: Cuestionario autoadministrado en una muestra aleatoria de 726 mujeres, de entre 18 y 23 años. Se compararon dos grupos, con y sin determinados tipos de problemas de sueño, en relación a síntomas de TCA. Resultados: Un 10,7% de la muestra refirieron problemas subjetivos graves de sueño, un 16,2% indicios de atracón, y un 6,7% necesidad impulsiva de vomitar tras las comidas. Los problemas de sueño específicamente asociados con síntomas de TCA fueron las dificultades para mantener el sueño y la sensación de no haber tenido un sueño reparador. En contra de lo esperado, no se encontró asociación entre el despertar precoz y los síntomas TCA, ni tampoco con un bajo Índice de Masa Corporal. Conclusiones: Los síntomas de TCA entre mujeres jóvenes parecen estar asociados a la dificultad para mantener el sueño y a la sensación de no haber tenido un sueño reparador.
Introduction
Sleep-wake disorders are frequent in young adults and its presence can cause disturbances in the quality of daytime life and poor academic performance.
Objective
To assess the prevalence of sleep-awake disorders in fifth year students at the Faculty of Medicine, National University of Córdoba, in 2011and to relate the findings to the students average academic performance during the period under study
Material and method
During the Neurology course, male and female students were assessed through a structured survey, which requested information about demographic data, toxic habits, sleep-wake habits, severity of daytime sleepiness, and average performance in academic courses during the period under review. In order to assess sleep disorders, a survey which followed SLEEP-50 Questionnaire guideliness was conducted. In order to evaluate sleepiness, Epworth Sleepiness Scale was implemented.
Results
309 out of the 625 students were assessed. 60.19% were female with an average age of 23.56 ± 4.28 years. The average sleepiness was 8.18 ± 4.42 in the ESS, presenting, at least, a sleep disorder in 42.39% of cases. Students with sleep-wake disorders showed a higher level of sleepiness (p < 0,0001), a lower perception of sleep quality (p < 0,0001) and a lower average performance (p = 0,02), which was related to chronic sleep deprivation, delay at bedtime and lower perception of nighttime sleep quality.
Conclusions
This study demonstrates that sleep-awake disorders are common in the evaluated university students and that their poor academic performance is asociated to the presence of this disorder.
Objective: Daylight is an important zeitgeber for entraining the circadian rhythm to a 24-hr clock cycle, and especially within the Polar circle, which has long Polar nights several months each year. Phase delays in sleep timing may occur, but the mean shift is normally small. However, the individual variation in phase shifts is large, implicating moderating factors. Here we examined the role of several self-regulatory variables (mood and fatigue, behavioral habits and psychological self-regulation) as moderators of seasonality in sleep timing and chronotype.
Patients/Methods: A sample of 162 young adults (76% females; mean age, f=23.4 yrs, m=24.3 yrs) participated in a prospective study across three seasons (Sep, Dec, Mar) in Tromsø/Norway at 69°39’N. Sleep diary and sleep/health-related questionnaire data were collected at each time point.
Results: Sleep timing and chronotype were delayed during the dark period (Dec) compared with brighter photoperiods (Sep and Mar). Comparable effects were observed for insomnia, fatigue, mood (depression and anxiety), subjective health complaints, physical activity and school-related stress. Most importantly, depression and fatigue moderated the degree of seasonal shifting in sleep timing, whereas the other self-regulation indicators did not (i.e., eating habits, physical activity and psychological self-regulation).
Conclusions: Seasonality in sleep timing and chronotype was confirmed, and depressive symptoms during the dark period seem to exacerbate phase shifting problems for people living in sub-Arctic regions.
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