It takes a community to prevent suicide: The development, roll-out, and scientific evaluation of a regional systems intervention for suicide prevention (SUPREMOCOL)

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Tilburg University

It takes a community to prevent suicide

Hofstra, E.

Publication date: 2021

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Hofstra, E. (2021). It takes a community to prevent suicide: The development, roll-out, and scientific evaluation of a regional systems intervention for suicide prevention (SUPREMOCOL). Ipskamp Printing.

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The development, roll-out, and scientific evaluation of a regional

systems intervention for suicide prevention (SUPREMOCOL)

IT TAKES A COMMUNITY

TO PREVENT SUICIDE

Emma Hofstra

T

AKE

S

A

C

OMMUNITY

T

O PREVENT

SUICIDE

E

mma H

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fstr

a

UITNODIGING

voor het bijwonen van de openbare verdediging van het

proefschrift

It takes a community

to prevent suicide

The development, roll-out, and scientific evaluation of a regional systems intervention

for suicide prevention (SUPREMOCOL)

door

Emma Hofstra

op maandag 21 juni 2021 om 13:30 uur precies in de Aula van Tilburg University, Cobbenhagen

gebouw, Warandelaan 2, Tilburg.

Helaas kan er een beperkt aantal gasten op locatie aanwezig zijn. U bent van harte uitgenodigd de verdediging bij te wonen via de livestream:

tiu.nu/live. Emma Hofstra emma.hofstra@gmail.com 06-28559313 Paranimfen Renee Sagel Romy van Kuijk

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560515-L-bw-Hofstra 560515-L-bw-Hofstra 560515-L-bw-Hofstra 560515-L-bw-Hofstra Processed on: 25-5-2021 Processed on: 25-5-2021 Processed on: 25-5-2021

Processed on: 25-5-2021 PDF page: 1PDF page: 1PDF page: 1PDF page: 1

It takes a community to prevent suicide

The development, roll-out, and scientific evaluation of a regional

systems intervention for suicide prevention (SUPREMOCOL)

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form, broken ceramic objects are repaired with gold. According to Japanese aesthetics, fractures are a unique part of the object’s history that contribute to its beauty. Through the gold, the fracture is highlighted and given new meaning.

The research presented in this thesis was conducted at GGz Breburg / Tilburg University The research presented in this thesis was financially supported by ZonMw -the Netherlands Organisation for Health Research and Development (grant number: 537001002).

Colofon

Cover design by Emma Hofstra

Layout and design by Eduard Boxem | persoonlijkproefschrift.nl Printed by Ipskamp Printing | proefschriften.net

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It takes a community to prevent suicide

The development, roll-out, and scientific evaluation of a regional

systems intervention for suicide prevention (SUPREMOCOL)

Proefschrift

ter verkrijging van de graad van doctor aan Tilburg University

op gezag van de rector magnificus, prof. dr. W.B.H.J. van de Donk,

in het openbaar te verdedigen ten overstaan van een door het college voor promoties aangewezen commissie

in de Aula van de Universiteit op maandag 21 juni 2021 om 13.30 uur

door

Emma Hofstra

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Prof. dr. C.M. van der Feltz-Cornelis, York University, UK Prof. dr. Ch. van Nieuwenhuizen, GGzE/Tilburg University

Copromotor

Dr. I. Elfeddali, GGz Breburg/ Tilburg University

Promotiecommissie

Prof. dr. A.T.F. Beekman, Amsterdam UMC, GGz inGeest Dr. G. Franx, 113 Zelfmoordpreventie

Dr. L.A.M. van de Goor, Tilburg University

Prof. dr. A.M. van Hemert, Leids Universitair Medisch Centrum Prof. dr. G.E. Nagelhout, Maastricht University

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Chapter 1 General introduction 7

Part I Overall effectiveness of suicide prevention interventions in general Chapter 2 Effectiveness of suicide prevention interventions: a systematic

review and meta-analysis 25

Part II The development, roll-out, and scientific evaluation of a regional systems intervention for suicide prevention (SUPREMOCOL)

Chapter 3 A regional systems intervention for suicide prevention in the

Netherlands (SUPREMOCOL): study protocol with a stepped wedge trial design

59

Chapter 4 The implementation of the regional systems intervention for

suicide prevention SUPREMOCOL in daily practice: a mixed-methods evaluation of the intervention integrity

91

Chapter 5 Short-term efficacy of a regional systems intervention for

suicide prevention (SUPREMOCOL) in Noord-Brabant: a pre-post stepped wedge trial design

121

Part III Alternative factors that may influence suicide

Chapter 6 Springtime peaks and Christmas troughs: a national longitudinal

population-based study into suicide incidence time trends in the Netherlands

143

Chapter 7 The association between suicide-related media coverage and

suicide: a cross-sectional observational study 165

Chapter 8 Summary and general discussion 183

Nederlandse samenvatting 194

Dankwoord 207

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CHAPTER 1

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8

GENERAL INTRODUCTION

It takes a community to prevent suicide. The title of this dissertation derives from the African saying ‘It takes a village to raise a child’, which is about the whole community contributing to the development of a child in a safe and healthy environment. The same principle applies to the prevention of suicide. Suicide can best be prevented if all parties in the community and the public and mental health sectors simultaneously work together to prevent it. For example, training general practitioners to properly recognize suicidality is most effective when shame and taboo about suicidal ideation play less of a role in society, so that people dare to seek help. Moreover, the greatest effect of psychological and pharmacological treatment is achieved when people have swift access to mental health care, without experiencing barriers such as stigma or waiting lists. Thus, suicide prevention is a task for all of us, whether we are a general practitioner, psychiatrist, schoolteacher, friend, or even a stranger in the street passing by someone expressing signs of suicidal behaviour.

Need for suicide prevention

Tragedy of suicide

Some people feel so entrapped with problems in life that they no longer see a solution to their problems: they may not want to continue living like this. This entrapment is often accompanied by feelings of sadness, loneliness, and fear, which can completely control someone’s life. Death could seem like an escape from these unbearable feelings and thoughts; however, hardly anyone really wants to die – it is rather a need to end the pain (1). The person who suffers from suicidality is often not the only one who is in pain. These people have parents, partners, children, friends, brothers, sisters, neighbours, and colleagues. The family and loved ones may also go through a difficult time and might experience worries, anxiety, and powerlessness. If a suicide occurs, it can even affect entire communities, such as a church community, a school, or a sports club. It may even affect bystanders, such as people who find the person after the suicide has occurred or people who are unintentionally involved in the suicide such as for train drivers when the suicide takes place on the track (2-4). However, there are several forms of help available, making suicide in many cases preventable. Although feelings of shame or the idea of not being able to be helped can prevent people from disclosing their suicidal thoughts, at every stage of the course of suicidality, the process is still reversible, so seeking help is never too late. With the right help at the right time, a lot of suffering can be prevented (1).

Prevalence of suicide

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the world dies by suicide (1, 5). In Europe, just over 56,000 people take their own life every year, and in the Netherlands, the rate is a little less than 2,000 (6, 7). Suicide rates in the Netherlands showed a sharp increase of 37% between 2007 and 2013 (6). Noord-Brabant is one of the southern provinces of the Netherlands. In this province, suicide rates have – for over a decade – been higher than the national average. In 2015, Noord-Brabant even ranked second nationally (6). Hence, a targeted regional approach in Noord-Brabant was deemed to be needed (8, 9).

Definition and emergence of suicidal behaviour

Definition of suicidal behaviour

According to the Dutch generic module ‘Diagnosis and treatment of suicidal behaviour’, the term suicidal behaviour refers to all thoughts, intentions, preparations and/or attempts to kill oneself (10). The World Health Organization (WHO) defines suicide as ‘the act of deliberately killing oneself’; a suicide attempt as ‘any non-fatal suicidal behaviour’, which – according to the WHO – refers to ‘intentional self-inflicted poisoning, injury or self-harm which may or may not have a fatal intent or outcome’; and suicidal ideation is ‘thinking about suicide’ (1). The three above-mentioned behaviours together represent ‘suicidal behaviour’ (1). In this thesis, self-harm is not included in our definition of suicidal behaviour. Although it is difficult to distinguish self-harming behaviour with and without suicidal intent, and there may be some overlap, we do think it mainly comprises different behaviours, because in self-harm, the suicidal intent is not present. Moreover, euthanasia and physician assisted suicide are also not considered suicidal behaviour in the context of this thesis. Furthermore, the expression in behaviour can vary greatly from person to person (10). For example, suicidal behaviour can be acute or chronic, and it may have a societal (such as unemployment or financial problems) or a psychological (depression, personality disorder, or psychosis) basis. Due to the variety of manifestations, suicide is a complex phenomenon (1, 11-14).

Development of suicidal behaviour

The complexity of suicidal behaviour also lies in its development. It hardly ever arises because of a single cause; there are usually several factors that together lead to suicidality. It is often caused by a unique composition of biological, psychological, physical, and relational risk factors, which might co-occur with risk factors on the community, societal and health system level. Due to this complexity, the exact causes vary per person. While one person develops suicidal behaviour in a certain situation, another person might not in the same circumstances (10). A stress-diathesis model provides more insight into the development of suicidal behaviour. This model describes that the specific interaction between a sustainable predisposition, such as a biological vulnerability, with an acute stressor, such as a negative life event, might lead to suicidal behaviour (15). However, there are many predispositions associated with suicidality, such as low serotonin levels, certain genetic factors, and negative childhood adversities,

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and there are also many stressors, such as psychiatric disorders and negative life events. Moreover, although a psychiatric disorder is a major risk factor for suicide, only 2%–8% of people with a psychiatric disorder attempts suicide, indicating that having a psychiatric disorder is not the greatest predictor of suicidal behaviour (16). Therefore, the specific interaction between the predisposition and the stressor seems to lead to the development of suicidality (15). It is often accompanied by the feeling of entrapment. If a person is in an unbearable situation, and can no longer see a way out, the feeling of entrapment can arise. Suicide may then appear to be the only way out (10).

Preventing suicide

General principles of prevention

According to the Dutch National Institute for Public Health and the Environment [RIVM], the aim of prevention is ‘to ensure that people remain healthy by promoting and protecting their health and preventing or detecting diseases and complications of diseases at the earliest possible stage’. There are four classifications of prevention: 1) prevention focussing on specific target groups – for example, elderly people, people with a particular disease, or people with a low socio-economic status; 2) prevention focussing on a certain stage of a disease – for example, in healthy people to prevent them from becoming ill or in sick people to prevent them from becoming more ill; 3) certain types of prevention measures, consisting of measures to prevent diseases (such as vaccinations) and measures to promote or protect health; and 4) certain methods implementing interventions, such as information, legislation, and signalling (17). According to the first classification, a suicide prevention intervention can thus focus on either universal prevention – when it focusses on the general population – on selective prevention – when it focusses on certain groups in the general population at high risk for suicide – or on indicated prevention – when it focuses on individuals with increased suicide risk (10). According to the first classification, a suicide prevention intervention can thus focus on either universal prevention, when it focusses on the general population; on selective prevention, when it focusses on certain groups in the general population at high risk for suicide; or on indicated prevention, when it focuses on individuals with increased suicide risk (10).

Suicide prevention in (mental) health care

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many studies have found no effects, and the results of scientific studies may be biased due to several reasons (19). Thus, in general, more evidence is needed to know exactly which treatments work. Moreover, the health care sector may act on suicide prevention by improving access to care for people at risk for suicide (20). This also includes improving the chain of care and providing follow-up of people who have attempted suicide (18). Primary care also has an important role in this endeavour because early detection of suicide risk is crucial. Moreover, it is recommended to assess suicide risk at the earliest possible stage and to continue with this evaluation on a regular basis – for example, by means of a follow-up (10).

Suicide prevention in public health care

A disturbing finding in the care for vulnerable people in the Netherlands is that 60% of those who die by suicide had not received mental health care (21), whilst the risk for suicide is almost 50 times higher in patients with a psychiatric disorder compared with the general population (22). Therefore, the public health institutes [GGD-en] and the public mental health care [OGGZ] have an important role in the prevention of suicide, focussing on socially vulnerable people who deal with mental illness, addiction, loneliness, unemployment, or financial problems and need care, but might not receive it (23). These people can pose a risk to themselves, for example, when loneliness or neglect happens, or to their environment, for example, when they show aggressive behaviour. In the Netherlands, the public health institutes play a central role in suicide prevention, although their activities vary from institution to institution (17). Certain public health interventions are found to be effective in preventing suicide. These actions comprise, amongst others, gatekeeper training for public health or primary care providers, such as general practitioners, to recognize and treat mental disorders (18, 20).

Suicide prevention in the community

Communities may also play an important role in the prevention of suicide. Prevention interventions in the community can for example help to reduce stigma and they can focus on supporting people at risk for suicide, such as through follow-up or by connecting people in the community (24). A particularly important advantage of community interventions is that they are usually implemented sub-regionally, which allows them to fit in very well with the specific needs and opportunities in that sub-region, which could therefore also be a suitable option for the regional problem in Noord-Brabant (24). Researchers have already reported evidence for the effectiveness of several community interventions. These interventions comprise awareness campaigns such as school-based awareness programmes, gatekeeper training for community facilitators, and media training on the responsible reporting on suicide (18, 20). The media might also be involved to educate the general public (18). To prevent suicide in severely mentally ill people, community interventions may not have enough effect, and for them, a combined intervention on several domains might be needed (18).

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Suicide prevention by safety measures

Restricting access to highly lethal means of suicide is a prevention strategy that is very effective and for which there is much evidence in the literature (18, 20, 25). Examples are restricting access to firearms, pesticides, and medication, and placing barriers at jumping sites (25). There are various reasons why means restriction is so effective. A suicidal crisis often only comprises a brief moment in which impulsive behaviour can take place (26). Therefore, if an impulsive attempt can be prevented, it is not always followed by a second attempt. Moreover, most people have a preference (or an aversion) for a certain suicide method, and they do not use alternative methods when they do not have access to a certain preferred method (26, 27). If a person does use another method, because the highly lethal method was not accessible, the alternative method is often less lethal, which thus less often leads to death. In the Netherlands, the creation of barriers to lethal means has received extensive attention in the National Agenda for Suicide Prevention. Several parties are working together to make various situations safer, such as high buildings and responsible dispensing of medication. The Dutch railway sector is also very active in suicide prevention by restricting access measures (28).

Multilevel interventions

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Gaps and challenges in suicide prevention

Besides ample suicide prevention interventions and promising elements of interventions, several challenges in effective suicide prevention remain. In the Netherlands, four healthcare parties are primarily responsible for the chain of care regarding suicidal behaviour: general practitioners, emergency rooms in general hospitals, acute and consultative psychiatry, and mental health care (30, 31). In addition, public health parties are also involved in the prevention of suicide, such as the public health institutions, police, and care and safety houses. A major bottleneck in the chain is the continuity of care, which is caused by a lack of agreement among the parties on how best to arrange care (who does what and when). As a result, transitions between and within healthcare organisations become vulnerable situations (30, 31). If we zoom in to the situation in Noord-Brabant, an informal exploration with regional stakeholders indicated that the delivery of services by a well-functioning chain of care on multiple levels could be improved. A tentative explanation is that there is a lack of real-time communication among chain partners in the community setting, primary care, and the specialised mental health setting. The chain of care could be improved by clear communication and agreement on tasks and responsibilities (30, 31). In organizing an improved chain of care, several challenges remain.

First, suicide prevention is challenged by a proper identification of people at risk for suicide (32). As discussed before, suicide has many risk factors such as mental disorders (mostly depression), substance abuse, previous suicide attempts, suicidal ideation, job and financial problems, unbearable mental pain, lack of a support system, trauma, stigma, impulsive aggression, hopelessness, living alone, and being faced with loss (1, 32-34). Some of these risk factors are very common, and most of them are not unique for suicide. Their predictive power is thus very low (32, 35). Moreover, there is not yet a single tool, questionnaire, or instrument that can predict suicide and clinical assessment can also be very hard (36). This may be because signals of suicidality are not always well recognised or assessed; indeed, patients might present atypical complaints or professionals might find suicidality difficult to discuss (37, 38). Previous research has shown that a majority of the people who died from suicide had been in contact with primary care within the year of death, and 45% even within one month (37, 39). However, predicting suicide is difficult. A large longitudinal study (N=4800) showed that the suicide risk of 60% of people who died from suicide was previously estimated as low by a mental health professional (40).

Second, a successful implementation of an intervention into practice remains a challenge. A Cochrane review indicated that the implementation of treatment guidelines succeeds better if nurses – instead of doctors – are trained with that purpose (41). Therefore, collaborative care, which is an intensive care model that involves a nurse and several professionals, such as a medical doctor, a case manager, and a psychiatrist, working together with a patient may be promising. The case manager has regular

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contact with the patient and organizes care, together with the medical doctor and specialist, and may offer help. There is ample evidence worldwide that collaborative care is successful in the treatment of depression (42-46). Collaborative care has also been shown to be feasible, acceptable, and effective in preventing and reducing suicidal ideation (18). In Noord-Brabant, collaborative care has not yet been systematically incorporated in a chain of care for suicide prevention.

Third, provision of swift access to care for those at risk is also a challenge that should be addressed (21, 34, 37, 47). The time after someone was suicidal remains very vulnerable for relapse. Indeed, we see that suicide occurs mostly in people not receiving mental health care and in transitions of and discharges from care (21, 47, 48). Although suicide risk is thirtyfold higher in people with a previous attempt, an attempt may not necessarily be followed by another one if proper mental health care is provided (1, 8, 18, 36). Swift access to care is thus also very important.

A fourth and final challenge is monitoring people at risk for suicide once they enter mental health care, as transitions into care can be vulnerable for renewed suicide attempts. In the first year after a person was suicidal, there are usually many transitions within (mental) health care settings. The risk of a relapse in suicidality increases during these transitions (49). There was often non-compliance with treatment and loss of contact with services prior to the suicide (49). Because making and keeping contact is the basis in communicating with a person who is suicidal, a long-term follow-up aiming to remain in contact with the person at risk might prevent people getting lost in transitions (10). Multiple reviews have reported that structured follow-up with high-risk individuals, such as people who attempted suicide, decreased future suicidal behaviour (18, 48, 50, 51).

Systems approach

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the contrary, we believe that most suicides are preventable. This is because, on the one hand, not all suicides are caused by mental disorders and thus could not be prevented by care and treatment solely, and, on the other hand, if a mental disorder is the cause, not all mental disorders can be immediately identified and treated (54). Wasserman et al. (55), who coined this with the term unnecessary death, have also advocated this view. We therefore adopted the concept of preventable suicide by intervening when someone shows suicidal behaviour, such as serious ideation or an attempt. We also followed the study example in Orange County by applying the systems intervention on suicide prevention. People at risk for suicide should be swiftly referred to a specialized centre to provide them with swift triage and specialized treatment to prevent them from getting lost in transitions. As far as we know, this is the first study that uses the systems approach in suicide prevention.

Suicide Prevention by Monitoring and Collaborative Care

Because suicide prevention can take place in several settings and due to the greater effect and synergistic potential when the intervention is simultaneously implemented in multiple settings, we aimed at decreasing the high suicide rate in Noord-Brabant by means of a multilevel intervention. Our intervention is named Suicide Prevention by Monitoring and Collaborative Care (SUPREMOCOL). This is the first regionally scaled collaborative effort for suicide prevention in Noord-Brabant. The target group of the intervention are people at increased risk for suicide. This comprises people who have attempted suicide, because a previous suicide attempt is a risk factor for suicide but may also comprise people with severe suicidal ideation (1). By this selection of the target group, SUPREMOCOL mainly focusses on indicated prevention – by an individual approach to persons at increased risk for suicide at the time – but because of the provincial-wide roll-out of the system, SUPREMOCOL also focusses on selective prevention, which further contributes to the integral approach (10). The aim of SUPREMOCOL is to lower suicide rates by 20% via four pillars. The first pillar concerns developing and implementing a monitoring system with decision aid to support professionals in reporting, assessing, and monitoring people at risk for suicide. A digital monitoring system was developed to enable professionals and community workers to communicate with each other. To identify as many people at risk for suicide as possible, we found it essential to involve both (mental) health care and non-(mental) health care professionals. The system is supported by a decision aid to help with risk appraisal, swift access, and monitoring over time. A first version of the decision aid was developed in the Depression Initiative, a national programme that ran in the Netherlands between 2006 and 2012 to improve standards of care for depressive disorder in the community, primary care, general hospital, and specialty mental health care settings (21). Parts of it were tested in a randomised clinical trial in the primary care setting by Huijbregts et al. (43). Based on the literature and in consultation with experts and stakeholders, the current version of the decision aid was developed in the programming phase of the current study. The questions from the decision aid – which can be answered with ‘yes’ or ‘no’ – are shown in Table 1.

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Table 1. Decision aid

Domain Question

In the past month 1. Did you have thoughts of being better off when you were dead, or did you wish you were dead?

2. Did you want to hurt yourself? 3. Did you have thoughts about suicide? 4. Did you make suicide plans? 5. Did you attempt suicide?

In life 6. Did you have thoughts of being better off when you were dead, or did you wish you were dead?

Clinical impression 7. Is there any acute danger in the behaviour of the person?

Based on the person’s answers, suicide risk is calculated, which can be high, moderate, or low. The algorithm for this calculation is shown in Figure 1. In the monitoring system, a cut-off is used, in which a moderate and high estimated risk are both labelled as ‘increased risk’.

Figure 1. Algorithm of the decision aid

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the participating specialized mental health institutions. Swift access was facilitated by the monitoring system and provided by the participating specialized mental health care institutions.

The third pillar concerned the positioning of nurse care managers to collaborate with psychiatrists in the assessment, case management, and guidance to treatment according to the collaborative care model. They would also signal potential problems in the continuity of care and would communicate this with the involved professionals. The fourth pillar of the intervention was providing telephone monitoring at five fixed times during one year to people registered in the monitoring system, to enhance adherence to treatment. This follow-up aimed to monitor the suicide risk and the continuation of care and was provided by the specialized mental health care institutions.

Aims and outline of this thesis

Following this introduction, this thesis is about the development, roll-out, and scientific evaluation of a regional systems intervention for suicide prevention (SUPREMOCOL) and in total consists of three parts. In Part I, we aim to evaluate the overall effectiveness

of suicide prevention interventions in general. Due to the indications for synergy in multilevel interventions, which means that the combined effect of the individual components of the intervention is more than the sum of the parts, we also examine this factor. This part comprises Chapter 2, which is a systematic review and

meta-analysis into the effectiveness and the potential of synergy of suicide prevention interventions. In Part II, we aim to describe the development, roll-out, and scientific

evaluation of SUPREMOCOL. This part comprises Chapter 3, which provides the study

protocol of the stepped wedge trial design of the regional systems intervention for suicide prevention (SUPREMOCOL); Chapter 4, which is about a mixed-methods

design study into 1) the extent to which SUPREMOCOL reached the target group and is adopted and implemented in practice and 2) hindering and facilitating factors regarding the implementation; and Chapter 5, which evaluates the short-term efficacy

of SUPREMOCOL on the prevention of suicides and suicide attempts by means of a pre-post stepped wedge trial design. In Part III, we aim to examine alternative factors that

may influence suicide, because suicide is a complex phenomenon requiring an integral approach and therefore more insight into factors contributing to the development of suicide is needed. This part comprises Chapter 6, which describes a longitudinal

population-based study into time trends in national daily and monthly data of 33,224 suicides that occurred in the Netherlands from 1995 to 2015, and Chapter 7, which

describes a cross-sectional observational study into the association between the publication of suicide-related media coverage and subsequent suicide. The findings and implications are discussed in the general discussion in Chapter 8.

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27. Law Ck, Sveticic J, De Leo D. Restricting access to a suicide hotspot does not shift the problem to another location. An experiment of two river bridges in Brisbane, Australia. Australian New Zealand Journal of Public Health. 2014;38(2):134-8.

28. 113 Suicide Prevention. Derde Landelijke Agenda Suïcidepreventie, 2021-2025 [Third National Agenda Suicide Prevention, 2021-2025] [Internet]. Amsterdam: 113 Suicide Prevention; 2020 [cited 2020 Oct 15]. Available from: https://. Dutch

29. Hegerl U, Wittmann M, Arensman E, Van Audenhove C, Bouleau J-H, van der Feltz-Cornelis C, et al. The ‘European Alliance Against Depression (EAAD)’: a multifaceted, community-based action programme against depression and suicidality. World Journal of Biological Psychiatry. 2008;9(1):51-8.

30. Hermens M, van Wetten H, Sinnema H. Kwaliteitsdocument Ketenzorg bij suïcidaliteit Aanbevelingen voor zorgvuldig samenwerken in de keten [Quality document chain care in suicidality recommendations for careful cooperation in the chain]. Utrecht: Trimbos-instituut; 2010. Dutch.

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31. van Hemert A, Kerkhof A, de Keijser J, van Boven C, Hummelen J, de Groot M, et al. Multidisciplinaire richtlijn diagnostiek en behandeling van suïcidaal gedrag [Multidisciplinary guideline diagnostics and treatment of suicidal behavior]. Utrecht: De Tijdstroom; 2012. Dutch.

32. Gvion Y, Apter A. Suicide and suicidal behavior. Public Health Reviews. 2012;34(2):9. 33. Hawton K, Arensman E, Wasserman D, Hulten A, Bille-Brahe U, Bjerke T, et al. Relation

between attempted suicide and suicide rates among young people in Europe. Journal of Epidemiology Community Health. 1998;52(3):191-4.

34. Hempstead KA, Phillips JA. Rising suicide among adults aged 40–64 years: the role of job and financial circumstances. American Journal of Preventive Medicine. 2015;48(5):491-500. 35. Powell J, Geddes J, Deeks J, Goldacre M, Hawton K. Suicide in psychiatric hospital in-patients:

risk factors and their predictive power. British Journal of Psychiatry. 2000;176(3):266-72. 36. O’Connor E, Gaynes B, Burda BU, Williams C, Whitlock EP. Screening for suicide risk in

primary care: a systematic evidence review for the U.S. Preventive Services Task Force [Internet]. Rockville (MD): Agency for Healthcare Research and Quality (US); 2013 Apr. Report No.: 13-05188-EF-1.

37. Luoma JB, Martin CE, Pearson JL. Contact with mental health and primary care providers before suicide: a review of the evidence. American Journal of Psychiatry. 2002;159(6):909-16.

38. Elzinga E, Gilissen R, Donker GA, Beekman AT, De Beurs DP. Discussing suicidality with depressed patients: an observational study in Dutch sentinel general practices. BMJ Open. 2019;9(4):e027624.

39. Leavey G, Rosato M, Galway K, Hughes L, Mallon S, Rondon J. Patterns and predictors of help-seeking contacts with health services and general practitioner detection of suicidality prior to suicide: a cohort analysis of suicides occurring over a two-year period. BMC Psychiatry. 2016;16(1):120.

40. Pokorny AD. Prediction of suicide in psychiatric patients: report of a prospective study. Archives of General Psychiatry. 1983;40(3):249-57.

41. Barbui, C., Girlanda, F., Ay, E., Cipriani, A., Becker, T., & Koesters, M. (2014). Implementation of treatment guidelines for specialist mental health care. Advances in Psychiatric Treatment, 20(2), 82-82.

42. van der Feltz-Cornelis C, Vlasveld M, H. A. Collaborative Care in Nederland. Eindrapport van het Depressie Initiatief [Collaborative Care in the Netherlands. Final report of the Depression Initiative]. Utrecht: Trimbos-institut; 2012. Dutch.

43. Huijbregts KM, de Jong FJ, van Marwijk HW, Beekman AT, Adèr HJ, Hakkaart-van Roijen L, et al. A target-driven collaborative care model for major depressive disorder is effective in primary care in the Netherlands. A randomized clinical trial from the depression initiative. Journal of Affective Disorders. 2013;146(3):328-37.

44. Archer J, Bower P, Gilbody S, Lovell K, Richards D, Gask L, et al. Collaborative care for depression and anxiety problems. Cochrane Database Syst Rev. 2012;10:CD006525. 45. Bruce ML, Ten Have TR, Reynolds III CF, Katz II, Schulberg HC, Mulsant BH, et al. Reducing

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46. Panagioti M, Bower P, Kontopantelis E, Lovell K, Gilbody S, Waheed W, et al. Association between chronic physical conditions and the effectiveness of collaborative care for depression: an individual participant data meta-analysis. JAMA psychiatry. 2016;73(9):978-89.

47. King EA, Baldwin DS, Sinclair JM, Baker NG, Campbell MJ, Thompson C. The Wessex recent in-patient Suicide study, 1: case–control study of 234 recently discharged psychiatric patient suicides. The British Journal of Psychiatry. 2001;178(6):531-6.

48. Luxton DD, June JD, Comtois KA. Can postdischarge follow-up contacts prevent suicide and suicidal behavior? Crisis. 2013(34):32-41.

49. Appleby L, Shaw J, Amos T, McDonnell R, Harris C, McCann K, et al. Suicide within 12 months of contact with mental health services: national clinical survey. BMJ. 1999;318(7193):1235-9.

50. Geulayov G, Casey D, Bale L, Brand F, Clements C, Farooq B, et al. Suicide following presentation to hospital for non-fatal self-harm in the Multicentre Study of Self-harm: a long-term follow-up study. Lancet Psychiatry. 2019;6(12):1021-30.

51. Cebrià AI, Parra I, Pàmias M, Escayola A, García-Parés G, Puntí J, et al. Effectiveness of a telephone management programme for patients discharged from an emergency department after a suicide attempt: controlled study in a Spanish population. Journal of Affective Disorders. 2013;147(1-3):269-76.

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55. Wasserman D. Suicide: an unnecessary death. Oxford: Oxford University Press; 2016.

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PART I

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CHAPTER 2 Effectiveness of suicide prevention interventions:

a systematic review and meta-analysis

This chapter has been published as:

Hofstra E, van Nieuwenhuizen Ch, Bakker M, Özgül D, Elfeddali I, de Jong JJ, et al. Effectiveness of suicide prevention interventions: a systematic review and

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ABSTRACT

Objective

This study provides an estimate of the effect size of suicide prevention interventions and evaluates the possible synergistic effects of multilevel interventions.

Method

A systematic review and meta-analysis were conducted of controlled studies evaluating suicide prevention interventions versus control published between 2011– 2017 in PubMed, PsycINFO, and Cochrane databases. Data extraction and risk of bias assessment according to ROBINS criteria were performed by independent assessors. Cohen’s delta was calculated by a random meta-analysis on completed and attempted suicides as outcomes. Meta-regression explored a possible synergistic effect in multilevel interventions. PROSPERO ID number: CRD42018094373.

Results

The search yielded 16 controlled studies with a total of 252,932 participants. The meta-analysis was performed in 15 studies with 29,071 participants. A significant effect was found for suicide prevention interventions on completed suicides (d=-0.535, 95% CI -0.898; -0.171, p=.004) and on suicide attempts (d=-0.449, 95% CI -0.618; -0.280, p<.001). Regarding the synergistic effect of multilevel interventions, meta-regression showed a significantly higher effect related to the number of levels of the intervention (p=.032).

Conclusions

Suicide prevention interventions are effective in preventing completed and attempted suicides and should be widely implemented. Further research should focus on multilevel interventions due to their greater effects and synergistic potential. Further research is also needed into risk appraisal for completed versus attempted suicide, as the preferred intervention strategy differs with regard to both outcomes.

Keywords

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INTRODUCTION

Rationale

Suicide is a worldwide major public health problem, with 800,000 suicides annually (1). Suicide attempts are among the most important known predictors of completed suicides, and occur even more often (1, 2). Since the 2013 commitment of the World Health Organization Member States to work towards suicide prevention (3), ample national strategies and suicide prevention interventions have been developed and overviews of them provided in systematic reviews (4-17). The effectiveness of suicide prevention interventions in reducing suicide rates is found in certain settings, but not (yet) in others (4, 8, 11, 12). In 2005, Mann et al. performed a systematic review pertaining to suicide prevention strategies in general (18); this review was updated by Zalsman et al. in 2016 (4). Despite growing evidence for the effectiveness of several suicide prevention strategies, until now a comparative estimate for the effect of different types of interventions has not yet been provided. Also, it remains unclear which strategy is the most effective and if the setting of intervention is relevant to the effect.

It has been argued that effective action towards reducing suicide would need combined interventions by different providers in multiple domains (3, 4, 18) – so-called multilevel interventions (19, 20). For example, at the community level, this could be accomplished by: (1) providing gatekeepers such as teachers and with priests training others to aid recognition of persons potentially at risk; (2) combining it with a publicity campaign (21, 22) and with (3) instructions to the press on how to publish information on suicides. In addition, on the primary care level, general practitioners could be trained on how to address suicidal thoughts and behaviour in patients. Indications of the effectivity of multilevel interventions were found in non-controlled studies (20, 23, 24); however, this effect was not replicated in one of the very few published randomised controlled trials examining the effectiveness of a multilevel intervention in preventing suicidal behaviour (22).

Multilevel interventions have been suggested as having synergistic potential (19), meaning that the effect of the combined parts of the intervention might create a stronger effect than the sum of the individual effects of the interventions. Hegerl et al. (2006) observed, during the implementation of a four-level community-based suicide prevention intervention, that general practitioners were more motivated to participate in the training sessions because the ongoing public campaign aimed at destigmatisation prompted their patients to present themselves with possible depressive symptoms and suicidal ideation (24). Synergistic interactions between intervention levels were also suggested by a qualitative study on multilevel suicide prevention interventions in four European countries (25). However, thus an estimate of a possible synergistic effect has not been provided (19, 20).

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Objectives

This study has three objectives:

1. To establish an estimate of the effect of suicide prevention interventions for completed suicides and suicide attempts;

2. To explore if the setting of intervention is associated with different effect sizes; 3. To explore if multilevel interventions have synergistic effects.

METHODS

Protocol and registration

The study protocol is registered in PROSPERO, the international prospective register of systematic reviews of the University of York (www.crd.york.ac.uk/prospero/) and is accessible under ID number CRD42018094373. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement for transparent reporting was followed (26).

Eligibility criteria

Studies were considered eligible if suicides and/or suicide attempts were included as an outcome and if a suicide prevention intervention was compared with a control group or period. Studies were included when randomisation was performed between patients or between practice settings (27), but could also be Controlled Cohort Studies (CCS), Controlled Before After studies (CBAs), Controlled Interrupted Time Series (CITS), or Interrupted Time Series (ITS) studies. Principal outcomes were suicide attempts and completed suicides and had to be defined in quantitative measures in order to make meta-analysis possible. The exclusion criterion was the inclusion of self-harm (non-suicidal self-injury; SH) in the target group for the intervention.

Information sources

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Search

A search was performed of systematic reviews of randomised or controlled studies in the field of suicide prevention interventions with MeSH terms and free text terms for ‘suicide prevention’ AND ‘intervention’ AND ‘systematic review’. A second search was run with ‘suicide prevention’ AND ‘intervention’ AND ‘clinical trial’. Randomised or controlled studies in the field of suicide prevention interventions were included. Only studies with a primary focus on suicide reduction were selected. The search strategy for PubMed is shown in the Appendix. It was adapted for the other databases. We did not use language restrictions to minimise ‘Tower of Babel Bias’ (28).

Study selection

After identifying studies from database searching and additional sources, duplicate records were removed. The titles and abstracts of the records were assessed to determine eligibility in a first screening and the full-text articles were assessed for eligibility in a second screening. The screenings were performed in duplicate (EH and DÖ). If the two independent assessors had disagreements in coding, a third assessor (CFC) was consulted to make the final decision.

Data collection process

An overview of participants, interventions, comparisons, outcomes, and study design (PICOS) is shown in Tables 1 and 2. The extraction of data was performed independently by two researchers (EH and DÖ). In the case of non-consensus, a third assessor (CFC) was consulted to make the final decision.

Data items

Two tables are provided, one for studies evaluating completed suicides and one for suicide attempts. Interventions are categorised as one level or multilevel, and the number of levels is provided by the third researcher of this study (CFC). The data items of each study are described below.

Type of study design Included studies could be Randomised Controlled Trials, Cluster

Randomised Controlled Trials, Controlled Cohort studies (CCs), Controlled Before After studies (CBAs), Controlled Interrupted Time Series (CITS) or Interrupted Time Series (ITS) studies.

Details of the intervention Suicide prevention strategies may include community

approaches, psychotherapeutic interventions, pharmacotherapeutic and multilevel interventions, with the prerequisite for inclusion that the intervention is sufficiently described to classify it as a suicide prevention intervention aimed at reducing attempted or completed suicides. The number of intervention levels was taken into account in the analysis, as was the setting, which could be the community, emergency room, outpatient specialty mental health setting or a psychiatric ward in a general hospital.

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Patient groups Targeted populations could be suicidal persons in the various settings

mentioned above; psychiatric patients, children and adolescents, older people, certain professional groups such as veterans, as well as ethnic minorities. There was no restriction on the kind of mental disorders.

Outcome definitions Outcomes were completed or attempted suicides in quantitative

measures, as defined by healthcare professionals (hospital records, questionnaires, or interview) or coroners records, as can be seen in Table 1 and 2. Measurement instrument and follow-up time were recorded.

Level of evidence Level of evidence was defined according to the criteria of the Oxford

Centre of Evidence-Based Medicine (29).

Risk of bias in individual studies

The quality of each study was determined by assessing the risk of bias in both the study and outcome level. Risk of bias (ROB) assessment was performed by two assessors (ChvN, MB) who discussed beforehand the required approach based upon the Cochrane Risk Of Bias in Non-randomised Studies – of Interventions (ROBINS-I) (30) and double-scored one of the articles. As no particularities in assessment were observed, all the other studies were individually assessed by the two assessors. In ROB appraisal, as confounding factors, co-therapies such as pharmacotherapy or psychotherapy on top of the suicide prevention intervention were considered, as well as including both suicidal persons and persons performing self-harm in the study. In the case of RCTs, the most important Cochrane quality criterion, namely randomisation (31, 32), was explicitly mentioned. The results of this risk-of-bias assessment are shown in Table 3. Furthermore, a meta-regression explored if an association existed between the risk of bias of the studies and the effect size of the interventions.

Summary measures

We used the rates of completed or attempted suicides in intervention and control conditions for pooling. We calculated the effect sizes for each study using Comprehensive Meta-analysis version 2 (33). We chose to take the following outcome measures into account for the analysis:

1) As a first step, the combined effect on completed and attempted suicides was analysed and labeled suicidal behaviour.

2) Subsequently, separate analyses on those two outcomes were performed, with larger negative effect sizes being an improvement compared to smaller negative effect sizes, and effect sizes above zero a deterioration.

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score of the control group (M_c) from the average score of the experimental group (M_e) and dividing the raw difference score by the pooled standard deviation of the experimental and control group (34). An effect size of 0.5 indicates that the mean of the experimental group is half a standard deviation larger than the mean of the control group. In general, one considers an effect size of 0.56–1.2 a large clinical effect, an effect size of 0.33–0.55 moderate, and an effect size of 0–0.32 as small (35, 36).

Synthesis of results

We performed a random-effects meta-analysis to examine the effectiveness of interventions on suicide prevention (37). Between-study heterogeneity was assessed using the Q-statistic (38), which reflects the observed dispersion. In order to quantify this dispersion, the I2_{statistic was used, which describes the percentage of total} variation across studies that is the result of heterogeneity rather than of chance. All statistical pooling was conducted using Comprehensive Meta-Analysis, version 2 (33).

Risk of bias across studies

Publication bias was examined by constructing a Begg funnel plot (39) and running a Stern & Egger test (40).

Additional pre-envisioned moderator analyses

The setting of the intervention was explored as a moderator. Also, suicide prevention interventions were labelled as multilevel if they contained elements that were performed in different settings and by different providers (19). Effect sizes of multilevel interventions were compared with effect sizes of non-multilevel interventions. In the case of multilevel interventions, an estimate of the effect was made to explore the potential of synergism by meta-regression. In the case of synergism, an exponential effect was expected.

RESULTS

Study selection

The database search identified 442 records. In addition, 172 records were identified by consulting suicide prevention experts (19 records) and by identifying studies from literature reviews about suicide prevention interventions (153 records). After removal of duplicates, 447 records remained. After screening the records on title and abstract, 389 records were excluded, and 58 articles were assessed for eligibility based on the full text (46 through database searching and 12 through additional sources). Finally, 16 studies were included in the systematic review. The study of Pearson et al. (2017) could not be pooled due to different outcomes, namely person-years. Hence, 15 studies were included in the meta-analysis, as is shown in Figure 1.

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Study characteristics

An overview of the study and characteristics with regards to participants, interventions, comparisons, outcomes, and study design (PICOS) for studies evaluating completed suicide and suicide attempts are presented in Tables 1 and 2. A total of 16 studies were included in the systematic review. Of these studies, 14 examined a unilevel suicide prevention intervention and two a multi-level intervention. Of the two multi-level interventions, one study included completed suicides as an outcome measure and one study attempted suicides.

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Risk of bias within studies

The quality ratings of the studies are shown in Table 3. Thirteen studies were randomised studies (RCTs). Two out of 16 studies (12.50%) had a low overall risk of bias, meaning that these studies ‘were comparable to a well-performed randomised trial’ (61). Nine studies had a moderate overall risk of bias (56.25%), meaning that these studies ‘provided sound evidence for a non-randomized study but cannot be considered comparable to a well-performed randomized trial’ (61). Five studies (31.25%) had a serious overall risk of bias, meaning that these studies ‘had some important problems’ (61). No studies showed a critical risk of bias. All studies were considered of sound quality according to the guidelines of the Oxford Centre of Evidence-Based Medicine (29). Hence, all studies were used in the analyses.

Results of individual studies

A total of 16 studies with 252,932 participants were selected for the systematic review. All studies were published in the time period of 2011–2017. Thirteen studies were (cluster) randomized controlled trials (81.3%) (41-43, 45, 47, 48, 51, 53, 55-59), two studies were a pre-post design study (12.5%) (49, 52), and one study was a case-controlled design (6.3%) (54). Fourteen interventions evaluated unilevel interventions (87.5%) (41-43, 45, 47-49, 51, 53-58) and two evaluated multilevel interventions (two-level: n=1, 6.3% (59); three-(two-level: n=1, 6.3% (52)). Two studies reported on the effect of suicide prevention interventions on completed suicides (12.5%) (47, 52), seven studies on attempted suicides (43.8%) (53-59), and seven studies reported on both (43.8%) (41-43, 45, 48, 49, 51). In five of the 16 studies, the setting was an outpatient specialty mental health institution (31.3%) (42, 45, 48, 56, 57), in four studies an emergency department (25.0%) (49, 53-55) or a community facility (25.0%) was involved (43, 51, 52, 59), and in three studies the setting was a psychiatric ward of a general hospital (18.8%) (41, 47, 58). Nine of 16 studies (56.3%) reported on participants who received treatment in a hospital (emergency room or psychiatric department) after non-fatal suicidal behaviour (41, 42, 47-49, 53-56). In four studies (25.0%) professional groups, such as soldiers, veterans, and police officers, were involved (45, 52, 57, 58). Participants from the community, such as from schools, were reported in three studies (18.8%)(43, 51, 59).

Synthesis of results

Overall meta-analysis. The study of Pearson et al., 2017 reported in person-years and

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favouring suicide prevention interventions over control conditions. The pooled estimate of effect size was d=-0.495 (95% CI -0.677; -0.313, p<.001). The forest plot is shown in Figure 2.

Figure 2. Forest plot suicidal behaviour

Heterogeneity (Q value) of this combined effect of suicide prevention interventions for all studies taken together was 32 (df=16, p=.011). The I2_{statistic was 50%, indicating} moderate heterogeneity, sufficiently to use a random model to fit the data, which was done in this analysis (Higgins). Because of this Q value and I2_{level of heterogeneity of} the combined outcomes, the further analyses were performed separately for completed suicides and attempted suicides.

Completed suicides. For suicide prevention interventions on completed suicides,

the pooled estimate was d=-0.535 (95% CI -0.898; -0.171, p=.004), which is a large, statistically significant effect. This effect is larger than the abovementioned combined effect. Q value for these studies was 6 (df=6, p=.455). The I2_{statistic was 0%, indicating} no heterogeneity. This is a robust effect. The forest plot is shown below.

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Figure 3. Forest plot of completed suicides

Attempted suicides. For suicide prevention interventions on attempted suicides, the

pooled estimate was d=-0.449 (95% CI -0.618; -0.280, p<.001), which is a moderate, statistically significant effect, slightly smaller than the above-mentioned combined effect. The forest plot is shown below. The Q value for these studies was 37 (df=14, p=.001). The I2_{statistic was 62%, indicating large heterogeneity.}