Article

Yoga as an Add-on Therapy in Parkinson’s Disease: A Single Group Open-label Trial

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Abstract

Objective We aimed to evaluate the effect of yoga on motor and non-motor symptoms and cortical excitability in patients with Parkinson’s disease (PD). Methods We prospectively evaluated 17 patients with PD at baseline, after one month of conventional care, and after one month of supervised yoga sessions. The motor and non-motor symptoms were evaluated using the Unified Parkinson’s disease Rating Scale (motor part III), Hoehn and Yahr stage, Montreal Cognitive Assessment, Hamilton depression rating scale, Hamilton anxiety rating scale, non-motor symptoms questionnaire and World Health Organization quality of life questionnaire. Transcranial magnetic stimulation was used to record resting motor threshold, central motor conduction time, ipsilateral silent period (iSP), contralateral silent period (cSP), short interval intracortical inhibition (SICI), and intracortical facilitation. Results The mean age of the patients was 55.5 ± 10.8 years, with a mean duration of illness of 4.0 ± 2.5 years. The postural stability of the patients significantly improved following yoga (0.59 ± 0.5 to 0.18 ± 0.4, p = 0.039). There was a significant reduction in the cSP from baseline (138.07 ± 27.5 ms) to 4 weeks of yoga therapy (116.94 ± 18.2 ms, p = 0.004). In addition, a significant reduction in SICI was observed after four weeks of yoga therapy (0.22 ± 0.10) to (0.46 ± 0.23), p = 0.004). Conclusion Yoga intervention can significantly improve postural stability in patients with PD. A significant reduction of cSP and SICI suggests a reduction in GABAergic neurotransmission following yoga therapy that may underlie the improvement observed in postural stability. Clinicaltrialsgov identifier CTRI/2019/02/017564

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While motor cortical areas are the main targets of the integrative activity of basal ganglia, their main output consists of the corticospinal system. Transcranial magnetic stimulation (TMS), a relatively new method to investigate corticospinal physiology, has been widely used to assess possible changes secondary to Parkinson's disease (PD). The use of single- and paired-pulse TMS, two varieties of the original technique, disclosed multiple functional alterations of the corticospinal pathway. For instance, when the latter was tested at 'rest', or in response to somesthetic afferents, it showed excess excitability or reduced inhibition. In turn, during production of a voluntary output, its activation was defective, or inadequately modulated. One major mechanism may be a dysfunction of the interneurons mediating the level of excitation within cortical area 4. For instance, there is a shortening of the so-termed 'central silent period', which is a complex, TMS-induced, inhibitory phenomenon possibly mediated by activation of GABA(B) receptors. The so-called 'short-interval intracortical inhibition', which is possibly mediated by GABA(A) receptors, is also diminished. Levodopa restores these and other TMS alterations, thus demonstrating that cortical area 4 is sensitive to dopamine modulation. Overall, TMS has provided substantial new pathophysiological insights, which point to a central role of the primary motor cortex in the movement disorder typical of PD. Repetitive (r-)TMS, another form of TMS, has been studied as a treatment for PD motor signs. Although some reports are favorable, others are not, and have raised the problem of appropriate control experiments. Although extremely interesting, the potential therapeutic role of r-TMS in PD needs further evaluation.
Article
Cognitive impairment of different severity with eventual progression to dementia in Parkinson’s disease (PD) appears during the course of the disease. In this study, transcranial magnetic stimulation (TMS) was used to assess cortical excitability changes in PD patients with varying cognitive impairment. We aimed to identify the TMS parameters that could serve as a non-invasive marker of cognitive impairment in patients with PD. Consecutive PD patients were recruited in the study. Detailed neuropsychological assessment was carried out to identify PD without cognitive impairment (PD-nC), PD with mild cognitive impairment (PD-MCI) and PD with dementia (PDD). Twenty patients of PDD (2 females and 18 males), 20 PD-MCI (4 females and 16 males), 18 PD-nC (5 females, 13 males) and 18 healthy controls (4 females, and 14 males) were included in the study. All the participants underwent TMS with recording of resting motor threshold, central motor conduction time, silent period, short interval intracortical inhibition (SICI) and intracortical facilitation (ICF). All the groups were age matched. The SICI was present in all; however, significantly greater inhibition was noted in PDD (Mean±SD; 0.11±0.08) followed by PD-MCI (0.31±0.17), PD-nC (0.49±0.26) and controls (0.61±0.23; p<0.001). The ICF was significantly reduced in PDD (Mean±SD; 0.15±0.18), PD-MCI (0.55±0.31), PD-nC (0.96±0.59), when compared to healthy controls (1.81±0.83; p<0.001). Patients with PD-nC, PD-MCI and PDD had graded reduction in ICF and increasing intracortical inhibition as the disease progressed from PD-nC through PD-MCI to PDD. This suggests progressive overactivity of GABAergic transmission, glutaminergic deficiency with consequent reduction of cholinergic transmission leading to dementia
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Background: Patients with Parkinson's disease (PD) commonly use complementary and alternative medications. Yoga is a mind-body intervention that is being increasingly explored as a tool in the therapeutic armamentarium of PD. Objective: To critically evaluate the studies and summarize the utility of Yoga in PD. Material and methods: We performed a systematic literature search in the Medline and Cochrane databases and included randomized controlled trials (RCT) of Yoga in PD. The studies were evaluated for internal validity and the relevant data were extracted. Results: A total of seven studies were included in the analysis. We collated the data on the changes in motor function, gait and balance parameters, anxiety, depression and quality of life scores observed after intervention (Yoga) in patients with PD and highlighted the limitations of these studies. Conclusion: Anxiety, depression, and balance issues in PD may benefit from Yoga. Yoga has potential as an add-on therapy in PD.
Article
Purpose Yoga may be a beneficial treatment for people with Parkinson’s disease (PD). However, no studies have critically reviewed and meta-analyzed the scientific evidence for yoga’s benefits regarding motor and non-motor symptoms. The purpose of this study was to conduct a systematic review and meta-analysis on the effectiveness of yoga as a rehabilitation strategy for PD. Materials and methods Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a literature search was performed using MEDLINE/PubMed, PEDro, SPORTDiscus, and Scopus. Studies addressing any concepts on the impact of yoga intervention on physical and psychological outcomes in people with PD were included. Results Fourteen RCTs were selected, with heterogeneous protocols and outcomes measures. Yoga interventions were safe and well-accepted for patients with mild to moderate PD. The descriptive analysis indicated that its practice might provide both physical and psychological benefits. Preliminary evidence showed that yoga has comparable or superior efficacy to exercise. A subsequent meta-analysis on five RCTs detected that yoga was more effective than passive control in ameliorating motor symptoms. Conclusions Yoga appears to be a promising rehabilitative therapy for individuals with PD. Recommendations are proposed for future studies. • IMPLICATIONS FOR REHABILITATION • Yoga is a safe and feasible therapy for people with mild to moderate PD. • Yoga practice positively impacts physical and mental health in this population. • When compared to exercise, yoga showed to have similar or even greater effects.
Article
Background: Rapid eye movement sleep behaviour disorder (RBD) is considered to be one of the most frequent and important prodromal symptoms of Parkinson’s disease (PD). We aimed to study the neurophysiological abnormalities in patients of PD-RBD and PD without RBD (PD-nRBD) using transcranial magnetic stimulation (TMS). Methods: Twenty patients each of PD-RBD and PD-nRBD were included in the study in addition to 20 age and gender-matched healthy controls. RBD was identified using the RBD screening questionnaire (RBDSQ). All the subjects were evaluated with single and paired-pulse TMS and parameters such as resting motor threshold (RMT), central motor conduction time (CMCT), silent period (SP), short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) were recorded. Results: The mean age of the controls and PD patients with and without RBD was comparable. There were no significant differences in RMT, CMCT and silent period between the two patient groups. SICI was present in all the three groups with significant inhibition noted in PD-RBD group (p<0.001). ICF was absent in patients of PD-RBD (0.19 ± 0.11) and PD-nRBD (0.7 ± 0.5) when compared to controls (1.88 ± 1.02) with profound impairment in patients with PD-RBD (p<0.001). The mean MoCA score was found to be significantly different in all the three groups with a worse score in patients with RBD (23.10 ± 2.55; p<0.001). Conclusions: Both PD-RBD and PD-nRBD patients have significant inhibition and absent intracortical facilitation suggesting enhanced GABAergic and reduced glutaminergic transmission. These abnormalities may underlie the different pathophysiological process observed in these patients.
Article
In Parkinson's disease, striatal dopamine depletion produces profound alterations in the neural activity of the cortico-basal ganglia motor loop, leading to dysfunctional motor output and parkinsonism. A key regulator of motor output is the balance between excitation and inhibition in the primary motor cortex, which can be assessed in humans with transcranial magnetic stimulation techniques. Despite decades of research, the functional state of cortical inhibition in Parkinson's disease remains uncertain. Towards resolving this issue, we applied paired-pulse transcranial magnetic stimulation protocols in 166 patients with Parkinson's disease (57 levodopa-naïve, 50 non-dyskinetic, 59 dyskinetic) and 40 healthy controls (age-matched with the levodopa-naïve group). All patients were studied OFF medication. All analyses were performed with fully automatic procedures to avoid confirmation bias, and we systematically considered and excluded several potential confounding factors such as age, gender, resting motor threshold, EMG background activity and amplitude of the motor evoked potential elicited by the single-pulse test stimuli. Our results show that short-interval intracortical inhibition is decreased in Parkinson's disease compared to controls. This reduction of intracortical inhibition was obtained with relatively low-intensity conditioning stimuli (80% of the resting motor threshold) and was not associated with any significant increase in short-interval intracortical facilitation or intracortical facilitation with the same low-intensity conditioning stimuli, supporting the involvement of cortical inhibitory circuits. Short-interval intracortical inhibition was similarly reduced in levodopa-naïve, non-dyskinetic and dyskinetic patients. Importantly, intracortical inhibition was reduced compared to control subjects also on the less affected side (n = 145), even in de novo drug-naïve patients in whom the less affected side was minimally symptomatic (lateralized Unified Parkinson's Disease Rating Scale part III = 0 or 1, n = 23). These results suggest that cortical disinhibition is a very early, possibly prodromal feature of Parkinson's disease.
Article
Background Idiopathic normal pressure hydrocephalus (iNPH) is characterized by the clinical triad of gait disturbance, urinary incontinence, and memory impairment with normal cerebrospinal fluid (CSF) pressure. Transcranial magnetic stimulation (TMS) has been used to assess the corticospinal motor pathways in patients with iNPH with conflicting results. Methods Our study included 11 patients with iNPH and 13 healthy controls. All the subjects underwent TMS and resting motor threshold (RMT), central motor conduction time (CMCT), short-interval intracortical inhibition (SICI), intracortical facilitation, and silent period (SP) were recorded in the upper limb. Besides, RMT and CMCT in lower limb were also recorded. Cognitive assessments were done using mini-mental status examination, Montreal cognitive assessment (MoCA), and Addenbrooke’s cognitive evaluation III (ACE III). Same parameters were recorded 24 h of CSF (lumbar puncture, LP) drainage. Results Mean age of the iNPH patients was 69.00 ± 6.71 years with age at onset being 66.64 ± 7.10 years. Duration of disease was 1.80 ± 1.25 years. A significant difference was noted in CMCT for the lower limb (CMCT-LL), SICI, and ipsilateral SP between pre-LP NPH and controls. Also, there was a significant difference in MoCA and ACE III between pre-LP NPH and controls. A significant reduction was observed in lower limb RMT between pre- and post-LP NPH patients. Post LP, there was a reduction in the lower limb CMCT and improvement in SICI. Conclusion A significant prolongation of CMCT-LL was observed in NPH patients. Lumbar CSF drainage in them resulted in a significant reduction in lower limb RMT thereby suggesting an increase in cortical excitability.
Article
Individuals with Parkinson's disease (PD) experience postural instability, low-back pain (LBP), and anxiety. These symptoms increase the risk of falls and decrease quality of life. Research shows yoga improves balance and decreases LBP and anxiety in healthy adults, but its effects in PD are poorly understood. All participants were part of a larger intervention study. Participants received pretest and posttest evaluations, including the Balance Evaluation Systems Test (BESTest), Beck Anxiety Inventory (BAI), and Revised Oswestry Disability Index (ROSW). Total scores for each measure, as well as individual balance system section scores from the BESTest (biomechanical constraints, stability limits/verticality, transitions/anticipatory, reactive, sensory orientation, and stability in gait) were compared within groups pre- to posttest. Participants in the yoga group ( n = 13) completed a twice-weekly 12-week yoga intervention, whereas controls ( n = 13) continued their usual routines for 12 weeks. Both the yoga ( Z = −3.20, p = 0.001) and control ( Z = −2.10, p = 0.040) groups improved on the BESTest total score. The control group showed no changes in individual balance systems, whereas the yoga group improved in stability limits/verticality ( Z = −2.3, p = 0.020), transitions/anticipatory ( Z = −2.50, p = 0.010), reactive ( Z = −2.70, p = 0.008), and sensory orientation ( Z = −2.30, p = 0.020). ROSW decreased in the yoga group only ( Z = −2.10, p = 0.030). BAI did not change in either group. Yoga is a nonpharmacological intervention that can improve balance and LBP in people with PD. This study demonstrated that yoga is feasible for people with PD, and participants reported high levels of enjoyment and intent to practice yoga after the study.
Article
Importance Clinical practice guidelines support exercise for patients with Parkinson disease (PD), but to our knowledge, no randomized clinical trials have tested whether yoga is superior to conventional physical exercises for stress and symptom management. Objective To compare the effects of a mindfulness yoga program vs stretching and resistance training exercise (SRTE) on psychological distress, physical health, spiritual well-being, and health-related quality of life (HRQOL) in patients with mild-to-moderate PD. Design, Setting, and Participants An assessor-masked, randomized clinical trial using the intention-to-treat principle was conducted at 4 community rehabilitation centers in Hong Kong between December 1, 2016, and May 31, 2017. A total of 187 adults (aged ≥18 years) with a clinical diagnosis of idiopathic PD who were able to stand unaided and walk with or without an assistive device were enrolled via convenience sampling. Eligible participants were randomized 1:1 to mindfulness yoga or SRTE. Interventions Mindfulness yoga was delivered in 90-minute groups and SRTE were delivered in 60-minute groups for 8 weeks. Main Outcomes and Measures Primary outcomes included anxiety and depressive symptoms assessed using the Hospital Anxiety and Depression Scale. Secondary outcomes included severity of motor symptoms (Movement Disorder Society Unified Parkinson’s Disease Rating Scale [MDS-UPDRS], Part III motor score), mobility, spiritual well-being in terms of perceived hardship and equanimity, and HRQOL. Assessments were done at baseline, 8 weeks (T1), and 20 weeks (T2). Results The 138 participants included 65 men (47.1%) with a mean (SD) age of 63.7 (8.7) years and a mean (SD) MDS-UPDRS score of 33.3 (15.3). Generalized estimating equation analyses revealed that the yoga group had significantly better improvement in outcomes than the SRTE group, particularly for anxiety (time-by-group interaction, T1: β, −1.79 [95% CI, −2.85 to −0.69; P = .001]; T2: β, −2.05 [95% CI, −3.02 to −1.08; P < .001]), depression (T1: β, −2.75 [95% CI, −3.17 to −1.35; P < .001]); T2: β, −2.75 [95% CI, −3.71 to −1.79; P < .001]), perceived hardship (T1: β, −0.92 [95% CI, −1.25 to −0.61; P < .001]; T2: β, −0.76 [95% CI, −1.12 to −0.40; P < .001]), perceived equanimity (T1: β, 1.11 [95% CI, 0.79-1.42; P < .001]; T2: β, 1.19 [95% CI, 0.82-1.56; P < .001]), and disease-specific HRQOL (T1: β, −7.77 [95% CI, −11.61 to −4.38; P < .001]; T2: β, −7.99 [95% CI, −11.61 to −4.38; P < .001]). Conclusions and Relevance Among patients with mild-to-moderate PD, the mindfulness yoga program was found to be as effective as SRTE in improving motor dysfunction and mobility, with the additional benefits of a reduction in anxiety and depressive symptoms and an increase in spiritual well-being and HRQOL. Trial Registration Centre for Clinical Research and Biostatistics identifier: CUHK_CCRB00522
Article
Background: The benefits of exercise in PD have been linked to enhanced dopamine (DA) transmission in the striatum. Objective: To examine differences in DA release, reward signaling, and clinical features between habitual exercisers and sedentary subjects with PD. Methods: Eight habitual exercisers and 9 sedentary subjects completed [¹¹C]raclopride PET scans before and after stationary cycling to determine exercise‐induced release of endogenous DA in the dorsal striatum. Additionally, functional MRI assessed ventral striatum activation during reward anticipation. All participants completed motor (UPDRS III; finger tapping; and timed‐up‐and‐go) and nonmotor (Beck Depression Inventory; Starkstein Apathy Scale) assessments. Results: [¹¹C]Raclopride analysis before and after stationary cycling demonstrated greater DA release in the caudate nuclei of habitual exercisers compared to sedentary subjects (P < 0.05). Habitual exercisers revealed greater activation of ventral striatum during the functional MRI reward task (P < 0.05) and lower apathy (P < 0.05) and bradykinesia (P < 0.05) scores versus sedentary subjects. Conclusions: Habitual exercise is associated with preservation of motor and nonmotor function, possibly mediated by increased DA release. This study formulates a foundation for prospective, randomized controlled studies.
Article
Yoga is a multifaceted spiritual tool with enhanced health and well-being as one of its positive effects. The components of yoga which are very commonly applied for health benefits are asanas (physical postures), pranayama (regulated breathing) and meditation. In the context of asanas, yoga resembles more of a physical exercise, which may lead to the perception that yoga is another kind of physical exercise. This article aims at exploring the commonalities and differences between yoga and physical exercise in terms of concepts, possible mechanisms and effectiveness for health benefits. A narrative review is undertaken based on traditional and contemporary literature for yoga, along with scientific articles available on yoga and exercise including head-to-head comparative trials with healthy volunteers and patients with various disease conditions. Physical exercises and the physical components of yoga practices have several similarities, but also important differences. Evidence suggests that yoga interventions appear to be equal and/or superior to exercise in most outcome measures. Emphasis on breath regulation, mindfulness during practice, and importance given to maintenance of postures are some of the elements which differentiate yoga practices from physical exercises.
Article
We studied prospectively the epidemiology, clinical impact and prediction of falls in 59 moderately affected patients with Parkinson's disease (PD) (mean UPDRS motor score 31.5; mean age 61 years) and 55 controls (mean age 60 years). At baseline, balance and gait were evaluated extensively. The retropulsion test (response to sudden shoulder pull) was executed first unexpectedly and five more times following prior warning. All persons used standardised scoring forms to document their falls during six months. Thirty patients (50.8 %) and eight controls (14.5%) fell at least once (relative risk [RR] 6.1; 95% confidence interval [CI] 2.5-15.1, p < 0.001). Recurrent (> or = 2) falls occurred in 15 patients (25.4%), but in only two controls (RR 9.0; 95 % CI 2.0-41.7; p=0.001). Recurrent falls were more common among persons taking benzodiazepines (RR 5.0; 95% CI 1.6-15.5; p < 0.01). Sixty-two percent of the falls in patients caused soft tissue injuries, but no fractures occurred. A fear of future falls was common (45.8 % of patients) and was accompanied by restriction of daily activities (44.1 % of patients). Seventy percent of falls reported by patients were'intrinsic' (due to patient-related factors), but falls in controls were mainly (50%) 'extrinsic' (due to environmental factors). None of the baseline posture and gait variables predicted falls adequately. The first 'unexpected' retropulsion test was more often abnormal than all subsequent (predictable) tests. Irrespective of its method of execution, the retropulsion test did not predict falls. A combination of asking for prior falls, disease severity and the Romberg test yielded the best overall diagnostic utility (sensitivity 65 % and specificity 98 %). Recurrent fallers were best predicted by disease severity (RR for Hoehn and Yahr stage 3 was > 100; 95% CI 3.1-585) and asking for prior falls (RR 5.0; 95% CI 1.2-20.9). We conclude that falls are common and disabling, even in relatively early stage PD. Recurrent fallers were best predicted by disease severity and presence of prior falls. Strategies to prevent falls in PD should particularly focus at intrinsic (patient-related) factors, such as minimising the use of benzodiazepines.
Article
Application of a single dose of a central nervous system (CNS) active drug with a defined single mode of action has been proven useful to explore and characterize the pharmacophysiological properties of transcranial magnetic stimulation (TMS) measures of motor cortical and corticospinal excitability in humans. With this pharmaco-TMS approach, it was demonstrated that different TMS measures reflect axon excitability (motor threshold), or inhibitory (cortical silent period, short-interval intracortical inhibition, long-interval intracortical inhibition, short-latency afferent inhibition) or excitatory synaptic excitability (motor evoked potential amplitude, intracortical facilitation, short-interval intracortical facilitation) of distinct neuronal elements in the CNS. Pharmaco-TMS has opened an exciting window into human cortical physiology. The array of pharmacophysiologically well defined TMS measures is now used by neurologists, psychiatrists, and clinical neurophysiologists for diagnosis or treatment monitoring in neuropsychiatric disease. This chapter reviews systematically the TMS measures of motor cortical and corticospinal excitability from the perspective of pharmacophysiological characterization. For example, it is demonstrated that blockers of voltage-gated sodium channels specifically increase motor threshold but do not alter other TMS measures of excitability, whereas positive modulators at γ-butyric acid (GABA) type A receptors, such as benzodiazepines, enhance short-interval intracortical inhibition and depress motor evoked potential amplitude but have no effect on motor threshold.
Article
It is unclear whether the age-associated reduction in baroreflex sensitivity is modifiable by exercise training. The effects of aerobic exercise training and yoga, a non-aerobic control intervention, on the baroreflex of elderly persons was determined. Baroreflex sensitivity was quantified by the alpha-index, at high frequency (HF; 0.15-0.35 Hz, reflecting parasympathetic activity) and mid-frequency (MF; 0.05-0.15 Hz, reflecting sympathetic activity as well), derived from spectral and cross-spectral analysis of spontaneous fluctuations in heart rate and blood pressure. Twenty-six (10 women) sedentary, healthy, normotensive elderly (mean 68 years, range 62-81 years) subjects were studied. Fourteen (4 women) of the sedentary elderly subjects completed 6 weeks of aerobic training, while the other 12 (6 women) subjects completed 6 weeks of yoga. Heart rate decreased following yoga (69 +/- 8 vs. 61 +/- 7 min-1, P < 0.05) but not aerobic training (66 +/- 8 vs. 63 +/- 9 min-1, P = 0.29). VO2 max increased by 11% following yoga (P < 0.01) and by 24% following aerobic training (P < 0.01). No significant change in alpha MF (6.5 +/- 3.5 vs. 6.2 +/- 3.0 ms mmHg-1, P = 0.69) or alpha HF (8.5 +/- 4.7 vs. 8.9 +/- 3.5 ms mmHg-1, P = 0.65) occurred after aerobic training. Following yoga, alpha HF (8.0 +/- 3.6 vs. 11.5 +/- 5.2 ms mmHg-1, P < 0.01) but not alpha MF (6.5 +/- 3.0 vs. 7.6 +/- 2.8 ms mmHg-1, P = 0.29) increased. Short-duration aerobic training does not modify the alpha-index at alpha MF or alpha HF in healthy normotensive elderly subjects. alpha HF but not alpha MF increased following yoga, suggesting that these parameters are measuring distinct aspects of the baroreflex that are separately modifiable.
Article
Transcranial magnetic stimulation (TMS) is a non-invasive tool for the electrical stimulation of neural tissue, including cerebral cortex, spinal roots, and cranial and peripheral nerves. TMS can be applied as single pulses of stimulation, pairs of stimuli separated by variable intervals to the same or different brain areas, or as trains of repetitive stimuli at various frequencies. Single stimuli can depolarise neurons and evoke measurable effects. Trains of stimuli (repetitive TMS) can modify excitability of the cerebral cortex at the stimulated site and also at remote areas along functional anatomical connections. TMS might provide novel insights into the pathophysiology of the neural circuitry underlying neurological and psychiatric disorders, be developed into clinically useful diagnostic and prognostic tests, and have therapeutic uses in various diseases. This potential is supported by the available studies, but more work is needed to establish the role of TMS in clinical neurology.
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Fluctuations in the symptoms of Parkinson's disease (PD), such as wearing-off and on-off effects, and dyskinesias are related to a variety of factors, including duration and dosage of levodopa, age at onset, stress, sleep, food intake, and other pharmacokinetic and pharmacodynamic mechanisms. The majority of patients, particularly those with young onset of PD, experience these levodopa-related adverse effects after a few years of treatment. Assessment of these motor complications is difficult because of the marked clinical variability between and within patients. Daily diaries have been used in clinical trials designed to assess the effects of various pharmacological and surgical interventions on motor fluctuations and dyskinesias. The most common type of dyskinesia, called "peak-dose dyskinesia", usually consists of stereotypical choreic or ballistic movements involving the head, trunk, and limbs, and occasionally, the respiratory muscles, whereas tremor and punding are less-common complications. Dystonia is also typically seen in patients with diphasic dyskinesia and wearing-off effect. Recognition of the full spectrum of clinical phenomenology of levodopa-related motor complications is essential for their treatment and prevention.
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As there are no biological markers for the antemortem diagnosis of degenerative parkinsonian disorders, diagnosis currently relies upon the presence and progression of clinical features and confirmation depends on neuropathology. Clinicopathologic studies have shown significant false-positive and false-negative rates for diagnosing these disorders, and misdiagnosis is especially common during the early stages of these diseases. It is important to establish a set of widely accepted diagnostic criteria for these disorders that may be applied and reproduced in a blinded fashion. This review summarizes the findings of the SIC Task Force for the study of diagnostic criteria for parkinsonian disorders in the areas of Parkinson's disease, dementia with Lewy bodies, progressive supranuclear palsy, multiple system atrophy, and corticobasal degeneration. In each of these areas, diagnosis continues to rest on clinical findings and the judicious use of ancillary studies.
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To determine characteristics of transcranial magnetic stimulation (TMS)-induced measures of central motor excitability to the paretic and nonparetic quadriceps muscles of chronic hemiparetic stroke patients in the context of a short-term, submaximal bout treadmill exercise. Cross-sectional. Motor control and gait biomechanics laboratory. Convenience sample of 11 patients including cohorts of treadmill untrained (n=8) and trained (n=3) stroke patients with chronic hemiparetic gait. Short-term submaximal treadmill exercise. Thresholds, amplitudes and latencies of TMS-induced motor evoked potentials at vastus medialis in paretic and nonparetic lower extremities. Baseline characteristics of the motor evoked potentials (MEPs) show significantly higher motor thresholds, longer latencies, and reduced amplitudes on the paretic side. In cross-sectional comparisons a group of treadmill-trained patients had greater paretic MEP amplitude changes after treadmill exercise versus paretic MEP responses from a group of untrained patients. These results indicate that treadmill training for 3 months or more may alter responsiveness of the lower-extremity central motor pathways to a short-term treadmill stimulus.
Article
The Unified Parkinson's Disease Rating Scale (UPDRS) is the main outcome measure in clinical trials of Parkinson's disease (PD). The minimal change that represents a clinically meaningful improvement is unknown. The objective of this study was to determine the minimal change on the UPDRS that represents a clinically meaningful improvement in early PD after 6 months of treatment. Data from two independent randomized treatment trials over 6 months involving 603 patients with de novo PD were analyzed to determine the minimal clinically important change (MCIC), referred to the status before treatment, for the UPDRS motor, activities of daily living (ADL), and total scores. An anchor-based method using ratings on a seven-point global clinical improvement was used. A change of five points on the UPDRS motor part was found to be the most appropriate cutoff score for all Hoehn and Yahr stages I to III, and a change of eight points for the UDPRS total score. For the UDPRS ADL score, an MCIC of two points for Hoehn and Yahr stages I/I.5 and II and of three points for Hoehn and Yahr stage II.5/III was the most appropriate cutoff score. These data give the first estimate for cutoffs defining clinically important changes in UPDRS ADL and motor scores. Further studies using larger databases from more diverse study populations are encouraged to better define and solidify the MCIC for the UPDRS.
Article
The practice of yoga regulates body physiology through control of posture, breathing, and meditation. Effects of yoga on autonomic functions of patients with refractory epilepsy, as quantified by standardized autonomic function tests (AFTs), were determined. The yoga group (n=18) received supervised training in yoga, and the exercise group (n=16) practiced simple routine exercises. AFTs were repeated after 10 weeks of daily sessions. Data were compared with those of healthy volunteers (n=142). The yoga group showed significant improvement in parasympathetic parameters and a decrease in seizure frequency scores. There was no improvement in blood pressure parameters in either group. Two patients in the yoga group achieved normal autonomic functions at the end of 10 weeks of therapy, whereas there were no changes in the exercise group. The data suggest that yoga may have a role as an adjuvant therapy in the management of autonomic dysfunction in patients with refractory epilepsy.
Article
Parkinson's disease (PD) is a progressive neurological disorder characterised by a large number of motor and non-motor features that can impact on function to a variable degree. This review describes the clinical characteristics of PD with emphasis on those features that differentiate the disease from other parkinsonian disorders. A MedLine search was performed to identify studies that assess the clinical characteristics of PD. Search terms included "Parkinson's disease", "diagnosis" and "signs and symptoms". Because there is no definitive test for the diagnosis of PD, the disease must be diagnosed based on clinical criteria. Rest tremor, bradykinesia, rigidity and loss of postural reflexes are generally considered the cardinal signs of PD. The presence and specific presentation of these features are used to differentiate PD from related parkinsonian disorders. Other clinical features include secondary motor symptoms (eg, hypomimia, dysarthria, dysphagia, sialorrhoea, micrographia, shuffling gait, festination, freezing, dystonia, glabellar reflexes), non-motor symptoms (eg, autonomic dysfunction, cognitive/neurobehavioral abnormalities, sleep disorders and sensory abnormalities such as anosmia, paresthesias and pain). Absence of rest tremor, early occurrence of gait difficulty, postural instability, dementia, hallucinations, and the presence of dysautonomia, ophthalmoparesis, ataxia and other atypical features, coupled with poor or no response to levodopa, suggest diagnoses other than PD. A thorough understanding of the broad spectrum of clinical manifestations of PD is essential to the proper diagnosis of the disease. Genetic mutations or variants, neuroimaging abnormalities and other tests are potential biomarkers that may improve diagnosis and allow the identification of persons at risk.
Functional improvements in Parkinson’s disease following a randomized trial of yoga
  • M Van Puymbroeck
  • A A Walter
  • Hawkins
  • Bl