The Association between Pathological Internet Use and Comorbid Psychopathology: A Systematic Review

Abstract

Background:
Pathological Internet use (PIU) has been conceptualized as an impulse-control disorder that shares characteristics with behavioral addiction. Research has indicated a potential link between PIU and psychopathology; however, the significance of the correlation remains ambiguous. The primary objective of this systematic review was to identify and evaluate studies performed on the correlation between PIU and comorbid psychopathology; the secondary aims were to map the geographical distribution of studies, present a current synthesis of the evidence, and assess the quality of available research.

Sampling and methods:
An electronic literature search was conducted using the following databases: MEDLINE, PsycARTICLES, PsychINFO, Global Health, and Web of Science. PIU and known synonyms were included in the search. Data were extracted based on PIU and psychopathology, including depression, anxiety, symptoms of attention deficit and hyperactivity disorder (ADHD), obsessive-compulsive symptoms, social phobia and hostility/aggression. Effect sizes for the correlations observed were identified from either the respective publication or calculated using Cohen's d or R(2). The potential effect of publication bias was assessed using a funnel plot model and evaluated by Egger's test based on a linear regression.

Results:
The majority of research was conducted in Asia and comprised cross-sectional designs. Only one prospective study was identified. Twenty articles met the preset inclusion and exclusion criteria; 75% reported significant correlations of PIU with depression, 57% with anxiety, 100% with symptoms of ADHD, 60% with obsessive-compulsive symptoms, and 66% with hostility/aggression. No study reported associations between PIU and social phobia. The majority of studies reported a higher rate of PIU among males than females. The relative risks ranged from an OR of 1.02 to an OR of 11.66. The strongest correlations were observed between PIU and depression; the weakest was hostility/aggression.

Conclusions:
Depression and symptoms of ADHD appeared to have the most significant and consistent correlation with PIU. Associations were reported to be higher among males in all age groups. Limitations included heterogeneity in the definition and diagnosis of PIU. More studies with prospective designs in Western countries are critically needed.

Full text

Int. J. Environ. Res. Public Health 2011, 8, 3938-3952; doi:10.3390/ijerph8103938
International Journal of
Environmental Research and
Public Health
ISSN 1660-4601
www.mdpi.com/jo urnal/ijerp h
Review
Internet Pathways in Suicidality: A Review of the Evidence
Tony Durkee 1,*, Gergo Hadlaczky 1, Michael Westerlund 2 and Vladimir Carli 1
1 The National Swedish Prevention of Suicide and Mental Ill-Health (NASP), Department of Public
Health Sciences, Karolinska Institutet (KI), Stockholm SE-171 77, Sweden;
E-Mails: gergo.hadlaczki@ki.se (G.H.); vladimir.carli@ki.se (V.C.)
2 Department of Journalism, Media and Communication (JMK), Stockholm University,
Stockholm SE-115 93, Sweden; E-Mail: westerlund@jmk.su.se
* Author to whom correspondence should be addressed; E-Mail: tony.durkee@ki.se;
Tel.: +46-8-5248-6935; Fax: +46-8-30-64-39.
Received: 5 September 2011; in revised form: 4 October 2011 / Accepted: 5 October 2011 /
Published: 11 October 2011
Abstract: The general aim of this study was to review the scientific literature concerning
the Internet and suicidality and to examine the different pathways by which suicidal risks
and prevention efforts are facilitated through the Internet. An online literature search was
conducted using the MEDLINE and Google Scholar databases. The main themes that were
investigated included pathological Internet use and suic idality, pro-suicide websites, suicide
pacts on the Internet, and suicide prevention via the Internet. Articles were screened based on
the titles and abstracts reporting on the themes o f interest. Thereafter, articles were selected
based on scientific relevance of the study, and included for full text assessment. The results
illustrated that specific Internet pathways increased the risk for suicidal behaviours,
particularly in adolescents and young people. Several studies found significant correlations
between pathological Internet use and suicidal ideation and non-suicidal self-injury.
Pro-suicide websites and online suicide pacts were observed as high-risk factors for
facilitating suicidal behaviours, particularly among isolated and susceptible individuals.
Conversely, the evidence also showed that the Internet could be an effective tool for
suicide prevention, especially for socially-iso lated and vulnerable individuals, who might
otherwise be unreachable. It is this paradox that accentuates the need for further research in
this field.
OPEN ACCESS

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Keywords: Internet use; pathological Internet use; pro-suicide websites; suicide pacts;
suicide prevention
1. Introduction
Suicidal behaviour is a compelling public health issue, particularly among adolescents and young
adult s. In Europe, it represents the second leading cause of mortality in the 10–24 year age-group [1],
and among youths aged 15–29 years, the prevalence of suicide in the European region is approximately
20 per 100,000 [2]. Completed suicides among male youths account for over 66% of all suicide cases;
whereas, female youths account for over 66% of all suicide attempts [3]. Research shows that for every
completed suicide, there are approximately 10–40 suicide attempts [4], with some estimates reporting
rates up to 100–200 times higher [5]. There is evidence showing an overall standardized prevalence
of 10.5% for suicide attempts among adolescents aged 15–16 years in Europe, with large variations
between countries, ranging from 4.1% to 23.5% [6]. Among youths who have previously attempted
suicide, 24% attempt suicide again within the following year [7]. In addition to suicide and suicide
attempt s suicida l ideation (SI) and non-suicidal self-injury (NSSI) levels also appear to be elevated.
Like in the case of attempts, there are considerable variations in the standardized prevalence of suicidal
ideat ion among the general populat ion in Europe, ranging from 1.1% to 19.8% [8]. From a global
view, the estimated prevalence of suicide attempts, plans and ideation ranged from 0.4%–4.2%;
1.1%–15.6%; to 2.6%–25.4%, respectively [9]. The annual prevalence of NSSI is estimated to be
around 7%, with lifetime rates between 12–13% [10]. NSSI rates appear to be higher among females
than males [11].
The link between suicidal behaviour and psychopathology is relatively substantiated in the
literature [12-15]; however, the connection is multifaceted. External factors that may affect the
relationship between suicidal behaviour and mental health should be taken into consideration during
risk assessment and prevention efforts. Among those factors which have particular relevance today, is
Internet use. The Internet can serve as a channel with positive and/or negative effects on users’
psychological health and well-being. Alao et al. [16] and D’Hulster and Van Heeringen [17] shared
this ambivalence, and suggested that the Internet can encourage suicidal behaviour by its supply of
descriptions of suicide methods and pro-suic ide websites, wherein individuals with severe mental
health problems are advised not to seek help and, at the same time, if the Internet is used properly, it
can also be a key resource for helping potentially suicidal individuals.
Referred to as the Internet paradox [18], both positive and negative effects of Internet use are
observed. Observed positive effects of the Internet include the ability to utilize and disseminate
information quickly and accessibly. In this context, Internet use appears very effective in a number of
areas such as providing health information [19], serving as a platform for education [20], social networks
and support [21], entertainment [22], and even mental health promotion and prevention programs [23].
The negative consequences of Internet use often coincide with social and risk-behavioural problems.
Research shows that adolescents who are susceptible to social exclusion, bully victimization and
substance abuse may utilize the Internet as a coping mechanism in an attempt to relieve stress [24]. It

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is under such conditions that adolescents become the most vulnerable for incipient online risks,
including cyber-bullying, pathological Internet use, pro-suicide websites, facilitatio n o f suicide pacts,
and expedition of suicidal methods [25,26]. As global Internet user rates are rising, the reliance on the
Internet and ensuing online risks are increasing as well.
Internet use has grown exponent ially worldwide, comprising now nearly two billion users [27].
With regards to geographic distribution, in 2010 the largest number of Internet users was located
wit hin the Asian region, which accounted for 42% of global Internet users (Figure 1). Europe
accounted for the second highest regio n, with 24.2%, followed by North America (13.5%), Latin
America (10.4%), Africa (5.6%), Middle East (3.2) and Oceania/Australia (1.1) [27].
Figure 1. Internet users distributed by geographic region in 2010. Source: Internet World
Stats, 2010 [27].
The increase in Internet usage is also illustrated predominantly among the adolescent age-groups. In
EU-27, statistics demonstrate that 90% of young people aged 16–24 years used the Internet regularly
during 2010 [28]. Due to the widespread use of the Internet on most continents, research concerning its
implications on mental health and suicidal behaviours necessitate scientific review.
The general aim of this study was to review the scientific literature concerning the Internet and
suicidality; and examine the different pathways by which suicidal risks and prevention efforts
are facilitated through the Internet. The main themes that were investigated included: pathological
Internet use and suicidality, pro-suicide websites, suicide pacts on the Internet, and suicide prevention
via the Internet.
2. Methods Section
An online literature search was conducted using the MEDLINE and Google Scholar databases.
There were no restrictions on language, time or on publication status, however, only articles published in
English were found. The main identifier used in the search was Internet combined with co-identifiers:
suicide or suicide attempt or suicidal thoughts or suicidal ideation or suicidal behaviour or suicide pacts
or pro-suicide or pathological use or addiction or mental health or prevention or intervention.
42.0%
24.2%
13.5%
10.4%
5.6% 3.2%
1.1%
Asia
Europe
North America
Latin America
Africa
Middle East
Oceania/Australia

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The only criteria were to include studies reporting on one or more of the following main themes:
pathological Internet use and suicidalit y, pro-suicide websites, suicide pacts on the Internet, and/or
suicide prevention via the Internet. Articles were screened based on the titles and abstracts reporting on
the themes of interest. Thereafter, articles were selected based on scientific relevance of the study, and
included for full text assessment. An evaluation of the assessed papers was performed, and a synthesis
of the results was summarized for each main theme.
3. Results and Discussion
3.1. Pathological Internet Use and Suicidality
Pathological Internet use (PIU), also referred to as Internet addiction [29], has been gaining
attention in recent years, partly due to its potential inclusion in the Diagnostic and Statistical Manual
of Mental Disorders, 5th Edition (DSM-V) nosological system [30,31]. PIU has been conceptually
modelled as an impulse-control disorder [32] that shares characteristics similar to behavioural
addiction: salience, mood modification, tolerance, withdrawal symptoms, conflict and relapse [33,34].
In an attempt to define and classify PIU, Young developed an assessment tool ent itled Young’s
Diagnostic Questionnaire for Internet Addiction (YDQ) [35]. The YDQ was developed according to
the DSM-IV diagnostic criteria for pathological gambling. In the YDQ, the diagnosis for addiction is
based on a pattern of Internet usage, over the past six months, which result in a clinical impairment or
distress as indicated by the following criteria: (i) preoccupation with the Internet; (ii) need for longer
amounts of time online to achieve satisfaction; (iii) repeated unsuccessful efforts to control, cut back,
or stop Internet use; (iv) restlessness, moodiness, depression, or irritability when attempting to cut
down or stop Internet use; (v) staying online longer than originally intended; (vi) jeopardizing or
risking the loss of a significant relationship, job, or educational or career opportunity because of the
Internet; (vii) lying to family members, therapists, or others to conceal the extent of involvement with
the Internet; and (viii) using the Internet as a way of escaping from problems or of relieving a
dysphoric mood [32,35]. The sum of the score is calculated based on the number of ‘Yes’ responses
and ranges between 0–8. Those scoring 3–4 are considered ‘at-risk’ fo r addiction and those individuals
scoring ≥5 are assumed to be pathological Internet users. The YDQ is utilized to measure pathology
concerning Internet use and not only excessiveness, and has also been validated in several
studies [36,37]. Despite the controversy surrounding non-standardized measures for PIU, there is
research showing significantly associated risks that are remarkably consistent [38].
PIU appears to have substantial negative effects in many aspects of an individual’s well-being, such
as cognition, emotion and social functioning [39,40]. Essentially, there are several cross-sectional
studies conducted in this area, which suggest a potential correlation between PIU and depression [41],
anxiety disorders [42], obsessive-co mpulsive disorders [41], and anti-social behaviours [43].
Three studies were identified in the literature that examined the direct link between PIU and
self-destructive behaviours related to suicidality (i.e., two on suicidal ideation [44,45] and one on
non-suicidal self-injury [46]). Both studies examining PIU and suicide ideation found significant
correlations, wherein pathological users had a three-to-four-fold higher risk of suicide ideat ion
compared to non-addicted individuals. Moreover, Lam and colleagues [46] examined an adolescent

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sample of 1618 high school students aged 13–18 years. The authors investigated the correlation
between PIU and non-suicidal self-injury (NSSI) behaviours. The results revealed that adolescents
categorized as moderately and severely addicted to the Internet had a significantly increased risk of
self-harm behaviours (OR: 2.0; 95% CI: 1.1–3.7) when compared with non-addicted adolescents [46].
For the reasons described above, PIU and suicidal behaviours can be considered as one o f the
pathways in the multifaceted risks for suicidality. Other risks include pro-suicide content disseminated
on websites, which essentially jeopardizes suicide preventive efforts.
3.2. Pro-Suicide Websites
The Internet provides an assortment of viable websites providing endless access to information.
However, is the information persons are retrieving always correct, or even safe? At present, there are a
large number of pro-suicide websites in several different languages on the Internet, and they often rank
high on the search engines’ results pages [47]. These often interlinking websites feature similar
characteristics in offering content, wherein suicidal acts are promoted, and typically utilized as a
means for individuals to cope with problems in life. In some instances, while no motivation is given,
taking one’s life is encouraged as a form of rebellion against the prohibition of suicide [48]. Becker
and Schmidt [49] have termed this aspect as a clear ‘anti-psychiatric’ view, which manifests itself
through disseminating information on the most effective ways to commit suicide, as well as
propagating that suicide should be reflected as an individual choice. On pro-suicide websites, society
and its institutions are seen as a threat to the individual’s ‘natural rights’ to take their lives. These
messages reach a relatively large number of vulnerable persons, with social and psychological
problems, as well as those who are actually seeking help on the Internet.
The existing studies on pro-suicide websites have mainly focused on the classification of website
content. This is performed by entering keywords and phrases related to suicide into a search engine.
Websites ranking highest in the search are scrutinized for suicidal content and profiled as pro-suicide,
suicide-neutral or anti-suicide [49-52].
Biddle and colleagues [47] conducted a study in which they examined various search engines,
including Google, Yahoo!, MSN and ASK, and the outcomes each particular search engine displayed
when entering select keyword and phrases, e.g., (a) suicide; (b) suicide methods; (c) suicide sure
methods; (d) most effective methods of suicide, etc. [47]. Subsequently, as users seldom look beyond
the first ten hits on the results page, the study outcomes were thus confined to this criterion. This
generated a total of 480 results. The study indicated that nearly 30% of the content of web pages was
subjugated by material concerning suicide methods. Suicidal acts ranged from incitement, provocation
to non-rejection. Conversely, 25% of the webpage content focused on suicide prevent io n, with a
distinctive opposition to suicidal behaviours, while 40% were construed as embracing, to some extent,
a position of suicide prevention [47,48].
Recupero and colleagues [53] investigated the accessibility of harmful online resources for suicidal
persons. The authors utilized five popular search engines: Google, Yahoo!, ASK, Lycos and Dogpile.
The authors entered four suicide-related search terms: (a) suicide; (b) how to commit suicide; (c) suicide
methods; and (d) how to kill yourself. Search outcomes were categorized as pro-suicide, anti-suicide,
suicide-neutral, not a suicide site, or error (i.e., page would not load). Results showed 373 web pages

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comprising suicidal cont ent. Among those web pages, 11% were considered to be contain obvious
pro-suicide mat erial; 30% was deemed to be suicide-neutral, and 29% was anti-suicide [48,53].
It is important to note that pro-suicide communication on the Internet seems to have become more
common over time. A study using the Google search engine to investigate the prevalence of suicide-
related material on the Internet showed that there was a proportional increase in pro-suicide messages
and discussions between 2005 and 2009 [54].
In the 2009 study Internet monitoring of suicide risk in the population, McCarthy [55] utilized a
service provided by Google, entitled Google Trends. This service provides search volumes, i.e., data
about what information users have searched for over time. McCarthy compared the search volumes using
specific search terms as: (a) suicide, (b) teen suicide, (c) depression, (d) divorce and (e) unemployment
with statistics on suicide and NSSI from the US Center for Disease Control (CDC). The results showed
that the Google search volumes correlated with both suicide and NSSI; however, differed among
age-groups [55]. The population, as a whole, displayed an overall negative correlation, i.e., in periods
of higher search volumes for the above-mentioned keywords, there were a decrease in suicides and
self-harm acts. According to the author, this could be explained by the fact that most persons use the
Internet fo r help-seeking reasons. In contrast to the general populat ion, there was a positive correlation
for young people between 15–25 years, i.e., in periods of high search volumes; there were an increase
in suicides and self-harm acts in this group. This indicates that young people, to a higher extent than the
general population, use the Internet for self-destructive purposes. The study supports the postulation of a
significant correlation between search activity on the Internet and suicide. Furthermore, the results
suggest that Internet searches on suicide-related terms can be a predictor of suicide and NSSI.
Pro-suicide websites are produced in opposition to socially dominant attitudes on the topic of
suicide [56]. In our society, the issue remains to question the primacy or sanctity of life. To advocate
the individual’s ‘right’ to end their life is the primary argument from the pro-suicide view. It is an
effective weapon in the struggle against society’s established morals and values. Descriptions of
suicide on pro-suicide websit es are, thus, tools for distinguishing the self and the group from the
worldview of the dominant cult ure. Although construction of the pro-su icide approach can, in many
ways, reflects a destructive activity, it also constitutes a meaningful activity for its protagonists. The
reasons why pro-suicide content is produced and available for public access is perhaps conceived as a
meaningful identity-constructive role it fulfils for the producers.
Baker and Fortune [57] argued that discussions in various studies and media have been too
generalized, lacking in-depth knowledge concerning Internet communication on suicide and self-harm,
and its insinuation for those involved. Based on ten in-depth interviews, with people who regularly
visited self-injury and suicide forums, the authors concluded that these forums provided participants a
source of empathy, fellowship and coping with social and psychological problems.
Westerlund [58] noted that visitors on interactive suicide forums are provided with an opportunity
to discuss difficult experiences, which would not be possible in most other contexts. Participants are
not held accountable to inst itutio nal figures or regulations. Their discussions, however, can potentially
be destructive, wherein information concerning potent suicide methods are discussed and exchanged,
and participants exhort one another to follow through with their suicidal plans. The atmosphere can
also be aggressive, with elements of verbal insults and bullying, possibly having a negative impact on
individuals who already feel exposed and vulnerable. At the same time, a comforting, supportive and

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understanding attitude can be found in many exchanges. There is an opportunity to meet other people
who share similar experiences, wherein their thoughts and feelings are not condemned nor lectured
about. Supportive and consoling discussions, composited with aggressive and destructive elements,
become a flow of polyphonic voices. In view of this ambiguity, it is important to take a balanced view
and avo id focusing solely on the potential risks inherent in chat rooms such as these.
Notwithstanding, pro-suicide websites are detrimental among a subgroup of persons with mental
health problems, especially if the person is susceptible to social isolation and lacks a social network to
counterbalance the negative information they may receive from such harmful websites. Pro-suicide
websites often provide an open forum to discuss methods and plans for committing the suicidal act
itself. Under these types of settings and circumstances is where suicidal pacts can emerge.
3.3. Suicide Pacts on the Internet: “Net Suicides”
The definition of a suicide pact is a cooperative choice by two or more individuals who agree that
both, or all, will commit suicide together, in a prearranged place and at a designated time [59].
Research concerning the Internet and suicidal behaviour, in this aspect, investigates what is known as
“net suicides”, i.e., suicide pacts made on the Internet [60].
Evidence shows that suicide pacts often develop in chat rooms or on message boards, which
endorse suicidal behaviours [49]. This milieu attracts vulnerable persons feeling socially excluded
fro m society [60]. The socially-isolated individual can communicate interactively and anonymously,
thus, exposing him/herself to impending pro-suicidal incitement from one or more parties involved.
This could potentially lead to the coordination of a suicide pact.
An example of such a tragedy occurred in Japan during 2004 when nine people took their own
lives, in a suicide pact, initiated and coordinated over the Internet [60]. According to Naito [61], in
Japan alone some 60 persons a year are presumed to have died from ‘net suicides’ and these trends
appear to be on the increase. However, this occurrence is not only limited to Japan. Online suicide
pacts have been reported in other nations as well, including the United Kingdom, Norway and
South Korea [48].
Destructive communication through Internet websites has augmented the suicidal risks for
vulnerable individuals. In some cases, persons are coerced into consenting to a suicide pact by
unknown accomplices. In other cases, acquaintances or friends decide collectively to formulate a
suicide pact. Notwithstanding, this phenomenon may explicate the spread of new suicide methods
across continents [62]. In Japan, during 2008, there was a sudden increase in hydrogen sulphide
poisoning, which developed as a potential method for committing suicide. This was eventually linked
to a website that disseminated material on a new technique for manufacturing gas, which was then
transmitted through message boards on the Internet. As the trend rapidly spread through Internet
communication, the new suicide method began emerging in other parts of the world [63].
In contrast to the potential risks of cyber technology, there is a clear advantage to having the ability
to quickly access information and to interactively communicate with individuals in real-time, while
maintaining anonymity. This Internet pathway has significant potential for promoting prevention
efforts and reaching vulnerable risk-groups.

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3.4. Suicide Prevention via the Internet
The prevention of suicide and suicidal behaviour is an important public health concern, yet, the topic
of suicide is st ill subjected to stigmatization [64,65]. Suicidal behaviour has shown to significantly
correlate with multiple psychopathologies, such as: depression [66,67], schizophrenia [68],
anxiety [69,70], impulsivity [71], social phobias [72], obsessive-compulsive [73] and affective
disorders [74]. Adolescents and young people often share comorbid risk-factors associated with
suicidality, which are not always a diagnosable disorder, rather are often presented through
risk-taking behaviours. There is substantial evidence showing a strong correlation between suicidality
and different forms of risk-behaviours, including: NSSI [75], substance abuse [76], tobacco use [77],
delinquency [78], aggression [79], bullying [80-82], and promiscuous sexual behaviour [83]. These
groups are the most susceptible for incipient suicidal behaviours. Therefore, this group would be the
ones who would probably benefit the most from receiving anonymous treatment online, wherein they
can openly discuss their feelings without being exposed to the stigmatization and taboo of discussing
mental health issues and suicidality. The ability to remain anonymous in a conversational community
increases the willingness to confess and discuss thoughts and feelings related to suicide, mental pain
and vulnerability, while reducing the risk of self-censorship [54]. Given the uniqueness of this specific
risk-group, the Internet can prove invaluable in reaching those individuals, who otherwise are
unattainable, in order to promote mental health and prevent suicidal behaviours.
Effective prevention strategies targeting this particular risk-group should include components that
increase awareness and help-seeking behaviours, while decreasing risk-taking and suicidal behaviours,
thereby, reducing stigma [84-87]. Wasserman and Durkee [88] have delineated specific approaches often
utilized in suicide preventive interventions, among which, includes the Universal/Selective/Indicated
(USI) model. In the USI model, the universal intervention targets the general population, t he selective
intervention targets subgroups at-risk for suicide, and the indicated intervention is aimed at high-risk
suicidal individuals who already begun self-destructive behaviours [89]. The USI model that adopts
the conceptual framework of increasing awareness, education and de-stigmatizing mechanisms would
be a theoretical basis in developing an effective Internet-based prevention program.
Literature suggests that web-based communication can provide support to suicidal individuals.
In one study, performed over a 11-month period, the results illustrated that the discussion members
on a website, converging on the theme of suicide, provided a supportive network, based on shared
experiences, sympathy, acceptance and encouragement [48].
In another study, a web-based intervent ion on treatment-seeking among college students at-risk
for suicidality was examined. Participants from two universities were invited to complete an online
survey that screened for depression and other suicidal risk-factors. Respondents received a modified
and personal assessment and were able to converse anonymously with an online clinical therapist.
Students classified as at-risk were advised to appear in-person for evaluation and treatment. Results
yielded 1162 students, in which 8% of invitees completed the screening questionnaire; 981 (84.4%)
were considered to be at high- or moderate-risk. Among this cluster, 190 (19.4%) joined a personal
examination session, and 132 (13.5%) entered therapy. Outcomes stipulated that students who engaged
in online discussions, with the clinical therapist, were three-times more likely than the in-person
attendees to come for evaluation and enter treatment [90].

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Although research on Internet-based suicide prevention is still fairly limited, there are examples of
promising suicide preventive interventions performed over the Internet [91,92]. There are many
advantages in using the Internet for prevention efforts; however, the theoretical concepts must be
developed pragmatically.
4. Conclusions
The Internet facilitates social and psychological interaction between individuals and enables easy
access to a broad array of information. This development has both positive and negative consequences
for suicidality. Given that adolescents constitute the majority of Internet users worldwide, they are
more likely to be influenced by the Internet. Individuals suffering from mental illness are already
predisposed to the dangers that lurk on the Internet, either on the basis of their psychological disorder,
or due to social isolation and/or limited social networks. On the other hand, they are also inclined to
receive the help that the Internet can provide. It is this paradox that encompasses research on Internet
pathways in suicidality.
Overa ll, the results of this review have illustrated specific Internet pathways that increase the risk
for suicidal behaviours, particularly in adolescents and young people. Several studies have found
significant correlations between PIU, suicidal ideation and NSSI. Pro-suicide websites and online
suicide pacts were observed as high-risk factors for facilitating suicidal behaviours, particularly among
susceptible individuals. Inversely, the evidence showed that the Internet could also be an effective tool
for suicide prevention, especially for socially-isolated and vulnerable individuals, who otherwise were
unattainable. This provides a basis to spread awareness, education and support required to promote
mental health and prevent suicidal behaviours.
Through the Internet, the preventive understanding of suicide is challenged by new voices, and the
battle over definitions of “right and wrong” and perceptions of “true and false” has intensified. The
possibility of reaching out to large groups of users is no longer monopolized by institutional senders.
These developments brought on by the wide spread use of the Internet have posed obstacles, as well as
benefits, in the field of suicide prevention.
Acknowledgments
The authors wish to thank staff at the National Swedish Prevent ion of Suicide and Mental Ill-Healt h
(NASP), Department of Public Health Sciences, Karolinska Institutet. In addition, special thanks to the
guest editors of this special issue, Prof Danuta Wasserman and Prof Gustavo Turecki.
Conflict of Interest
The authors declare no conflict of interest.
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