Association of chronic pain with suicide attempt and death by suicide: a two-sample Mendelian randomization.

Prior studies have suggested an association between chronic pain and suicidal behavior. However, evidence supporting the causal nature of this association, and the role played by depression, remain difficult to establish due to confounding. We investigated associations of chronic pain with suicide attempt and death by suicide as well as the mediating role of depression in this association using a genetically informed method strengthening causal inference. We conducted a two-sample Mendelian randomization. Independent SNPs (N = 97) from the multisite chronic pain GWAS (NGWAS = 387,649) were used as instrumental variables to test associations of chronic pain with suicide attempt (measured from hospital records; NGWAS = 50,264) and death by suicide (measured from official death causes; NGWAS = 18,085). Indirect associations of chronic pain with suicide attempt and death by suicide via major depressive disorder (NGWAS = 173,005) were estimated. Primary analyses were supported by a range of sensitivity and outlier analyses. We found evidence supporting the contribution of chronic pain to increasing the risk of suicide attempt (OR = 1.67, CI = 1.21-2.35) and death by suicide (OR = 2.00, CI = 1.10-3.62). Associations were consistent across sensitivity analysis methods, and no evidence for outliers driving these associations was found. Through mediation analyses, we found that major depressive disorder explained a substantial proportion of the association between chronic pain and suicide attempt (proportion mediated = 39%; ORindirect association = 1.32, CI = 1.09-1.61) and death by suicide (proportion mediated = 34%; ORindirect association = 1.40, CI = 1.13-1.73). Our findings suggest that both pain management interventions and prevention of depression are likely to be effective strategies to reduce suicide risk in individuals with chronic pain.

The role of depression and use of alcohol and other drugs after partner suicide in the association between suicide bereavement and suicide: cohort study in the Danish population.

BACKGROUND: Although suicide bereavement is associated with suicide and self-harm, evidence regarding mechanisms is lacking. We investigated whether depression and substance use (alcohol and/or other drugs) explain the association between partner suicide bereavement and suicide. METHODS: Linkage of nationwide, longitudinal data from Denmark for the period 1980-2016 facilitated a comparison of 22 668 individuals exposed to bereavement by a partner's suicide with 913 402 individuals bereaved by a partner's death due to other causes. Using causal mediation models, we estimated the degree to which depression and substance use (considered separately) mediated the association between suicide bereavement and suicide. RESULTS: Suicide-bereaved partners were found to have a higher risk of suicide (HRadj = 1.59, 95% CI 1.36-1.86) and of depression (ORadj 1.16, 95% CI 1.09-1.25) when compared to other-bereaved partners, but a lower risk of substance use (ORadj 0.83; 95% CI 0.78-0.88). An increased risk of suicide was found among any bereaved individuals with a depression diagnosis recorded post-bereavement (ORadj 3.92, 95% CI 3.55-4.34). Mediation analysis revealed that depression mediated 2% (1.68%; 95% CI 0.23%-3.14%; p = 0.024) of the association between suicide bereavement and suicide in partners when using bereaved controls. CONCLUSIONS: Depression is a partial mediator of the association between suicide bereavement and suicide. Efforts to prevent and optimize the treatment of depression in suicide-bereaved people could reduce their suicide risk. Our findings might be conservative because we did not include cases of depression diagnosed in primary care. Further work is needed to understand this and other mediators.

The iceberg model of suicidal ideation and behaviour in Danish adolescents: integration of national registry and self-reported data within a national birth cohort.

Hospital records are used to identify suicide attempts in many countries but not all individuals present to hospital after a suicide attempt i.e., suggesting a 'hidden number'. Our aim was to present the prevalence of suicide ideation, plans, attempts, and suicides among Danish adolescents, including attempts not resulting in hospital contact. The study population consisted of participants in the Danish National Birth Cohort participating in an 18-year follow-up, with individual-level linkage to national register data. Prevalence was estimated with a variable with mutually exclusive categories ranging from no suicidality to self-reported suicide ideation, -plans, -attempt and hospital-recorded suicide attempt and stratified on sex and parental income. The 'hidden number' was estimated as the ratio between suicide attempts with and without hospital contact. Among 47 858 participants, all aged 18-years, 36% girls and 28% boys reported suicide ideation at least once in their life. In addition, 6% girls and 3% boys had either reported or been recorded with a suicide attempt. For every attempt recorded in the hospital setting, two girls (ratio, 1:2) and six boys (ratio, 1:6) reported having attempted suicide without hospital contact. The prevalence of any suicide attempt was 8% and 3% in the lowest and highest income group, respectively. Before age 18, 0·011% girls and 0·016% boys had died by suicide. In conclusion, suicidal ideation and behaviour are common in adolescents and there is a substantial 'hidden number' of adolescents with suicide attempt. These results emphasize the need for early age suicide preventive interventions in community-settings e.g., school environments.

Association between SARS-CoV-2 infection and self-harm: Danish nationwide register-based cohort study.

BACKGROUND: Case studies have linked SARS-CoV-2 infection to suicidal behaviour. However, conclusive evidence is lacking. AIMS: To examine whether a history of SARS-CoV-2 infection or SARS-CoV-2-related hospital admission was associated with self-harm in the general population and in high-risk groups. METHOD: A cohort design was applied to nationwide data on all people aged ≥15 years and living in Denmark between 27 February 2020 and 15 October 2021. Exposure was identified as having had a positive SARS-CoV-2 PCR test, and further assessed as SARS-CoV-2-related hospital admission. Rates of probable self-harm were examined using adjusted incidence rate ratios (aIRRs). The following subgroups were identified: (a) lower educational level, (b) chronic medical conditions, (c) disability pension, (d) mental disorders, (e) substance use disorders, and history of (f) homelessness and (g) imprisonment. RESULTS: Among 4 412 248 included individuals, 260 663 (5.9%) had tested positive for SARS-CoV-2. Out of 5453 individuals presenting with self-harm, 131 (2.4%) had been infected. Individuals with a history of a positive SARS-CoV-2 test result had an aIRR for self-harm of 0.86 (95% CI 0.72-1.03) compared with those without. High rates were found after a SARS-CoV-2-related hospital admission (aIRR = 7.68; 95% CI 5.61-10.51) or a non-SARS-CoV-2-related admission (aIRR = 10.27; 95% CI 9.65-10.93) versus non-infected and not admitted. In sensitivity analyses with a more restrictive definition of self-harm, a positive PCR test was associated with lower rates of self-harm. CONCLUSIONS: Individuals with a PCR-confirmed SARS-CoV-2 infection did not have higher rates of self-harm than those without. Hospital admission in general, rather than being SARS-CoV-2 positive. seemed to be linked to elevated rates of self-harm.

Traumatic brain injury and risk of subsequent attempted suicide and violent crime.

BACKGROUND: Traumatic brain injury (TBI) can cause long-lasting sequelae that may increase the risk of suicidal or criminal behaviour, but large-scale longitudinal studies are lacking on the link between TBI and events of suicide attempt and violent crime. This study examined the incidence of suicide attempt and violent crime following hospital contact for TBI in a nationwide cohort study. METHODS: We used nationwide register data covering all individuals aged 10+ living in Denmark during 1980-2016 (n = 7 783 951). Of these, 587 522 individuals had a hospital contact for TBI. Incidence rate ratios (IRR) were calculated by Poisson regression analyses while adjusted for relevant covariates including other fractures and psychiatric diagnoses. RESULTS: Individuals with TBI had higher rates of suicide attempt (females IRR, 2.78; 95% CI 2.71-2.85; males IRR, 3.00; 95% CI 2.93-3.08) compared to individuals without TBI in adjusted analyses. Multiple TBI and temporal proximity to TBI were associated with higher rates of suicide attempt. Individuals with TBI had higher rates of violent crime (females IRR, 2.43; 95% CI 2.36-2.49; males IRR, 1.80, 95% CI 1.78-1.82) compared with individuals without TBI. Higher rates of violent crime were found after multiple TBI and temporal proximity to TBI. CONCLUSIONS: This nationwide cohort study found higher rates of suicide attempt and violent crime among individuals with prior hospital diagnosed TBI, compared with individuals without TBI. This emphasises the need for preventive efforts immediately after TBI diagnosis, which might mitigate the risks of a trajectory toward suicidal or violent behaviours.

Association between cannabis use disorder and schizophrenia stronger in young males than in females.

BACKGROUND: Previous research suggests an increase in schizophrenia population attributable risk fraction (PARF) for cannabis use disorder (CUD). However, sex and age variations in CUD and schizophrenia suggest the importance of examining differences in PARFs in sex and age subgroups. METHODS: We conducted a nationwide Danish register-based cohort study including all individuals aged 16-49 at some point during 1972-2021. CUD and schizophrenia status was obtained from the registers. Hazard ratios (HR), incidence risk ratios (IRR), and PARFs were estimated. Joinpoint analyses were applied to sex-specific PARFs. RESULTS: We examined 6 907 859 individuals with 45 327 cases of incident schizophrenia during follow-up across 129 521 260 person-years. The overall adjusted HR (aHR) for CUD on schizophrenia was slightly higher among males (aHR = 2.42, 95% CI 2.33-2.52) than females (aHR = 2.02, 95% CI 1.89-2.17); however, among 16-20-year-olds, the adjusted IRR (aIRR) for males was more than twice that for females (males: aIRR = 3.84, 95% CI 3.43-4.29; females: aIRR = 1.81, 95% CI 1.53-2.15). During 1972-2021, the annual average percentage change in PARFs for CUD in schizophrenia incidence was 4.8 among males (95% CI 4.3-5.3; p < 0.0001) and 3.2 among females (95% CI 2.5-3.8; p < 0.0001). In 2021, among males, PARF was 15%; among females, it was around 4%. CONCLUSIONS: Young males might be particularly susceptible to the effects of cannabis on schizophrenia. At a population level, assuming causality, one-fifth of cases of schizophrenia among young males might be prevented by averting CUD. Results highlight the importance of early detection and treatment of CUD and policy decisions regarding cannabis use and access, particularly for 16-25-year-olds.

Sense of psychological ownership in co-design processes: A case study.

INTRODUCTION: Service users are increasingly participating in health research. Although collaborative research is assumed to give users a sense of psychological ownership, little is known about the specific psychosocial processes through which ownership develops and is displayed. The present study yields insight into a process in which service users, researchers and a website designer collaborated to design a website. AIM: The aim of this study was to explore how participants developed and displayed feelings of ownership during a collaborative process to design a website. METHODS: A case study design was adopted by which audio recordings were subjected to thematic analysis and interpreted by drawing on the concept of psychological ownership. FINDINGS: A sense of psychological ownership of the website design process emerged in two distinct and overlapping phases. In the first phase, 'sense of ownership during the early design phase', only researchers and the website designer displayed a sense of ownership, which was facilitated by the research context preceding the collaborative workshops. In the second phase, 'sense of ownership during the collaborative design phase', service users gradually started to develop parallel feelings of ownership that were facilitated by workshop design activities. These activities enabled service users to increasingly control the process, to invest themselves in the process and to gain intimate knowledge of the process and its outcome. Service users' sense of ownership was displayed in their statements about the website and its elements. CONCLUSION: Participants engaged in codesign processes may develop a sense of psychological ownership at different speeds because of contextual factors. It is important to take this into account as it may complicate the formation of egalitarian work groups. PATIENT AND PUBLIC CONTRIBUTION: Parents of children with suicidal behaviour and a counsellor participated as service users in a website design process.

The effect of the SAFE intervention on post-discharge suicidal behavior: a quasi-experimental study using propensity score matching.

OBJECTIVES: The risk of suicidal behavior after discharge from psychiatric admission is high. The aim of this study was to examine whether the SAFE intervention, an implementation of a systematic safer discharge procedure, was associated with a reduction in suicidal behavior after discharge. METHODS: The SAFE intervention was implemented at Mental Health Center Copenhagen in March 2018 and consisted of three systematic discharge procedures: (1) A face-to-face meeting between patient and outpatient staff prior to discharge, (2) A face-to-face meeting within the first week after discharge, and (3) Involvement of relatives. Risk of suicide attempt at six-month post-discharge among patients discharged from the SAFE intervention was compared with patients discharged from comparison mental health centers using propensity score matching. RESULTS: 7604 discharges took place at the intervention site, which were 1:1 matched with discharges from comparison sites. During the six months of follow-up, a total of 570 suicide attempts and 25 suicides occurred. The rate of suicide attempt was 11,652 per 100,000 person-years at the SAFE site, while it was 10,530 at comparisons sites. No observable difference in suicide attempt 1.10 (95% CI: 0.89-1.35) or death by suicide (OR = 1.27; 95% CI:0.58-2.81) was found between sites at 6-month follow-up. CONCLUSION: No difference in suicidal behavior between the sites was found in this pragmatic study. High rates of suicidal behavior were found during the 6-months discharge period, which could suggest that a preventive intervention should include support over a longer post-discharge period than the one-week follow-up offered in the SAFE intervention.

The Effects of Internet-Based Cognitive Behavioral Therapy for Suicidal Ideation or Behaviors on Depression, Anxiety, and Hopelessness in Individuals With Suicidal Ideation: Systematic Review and Meta-Analysis of Individual Participant Data.

BACKGROUND: Suicide is a global public health problem. Digital interventions are considered a low-threshold treatment option for people with suicidal ideation or behaviors. Internet-based cognitive behavioral therapy (iCBT) targeting suicidal ideation has demonstrated effectiveness in reducing suicidal ideation. However, suicidal ideation often is related to additional mental health problems, which should be addressed for optimal care. Yet, the effects of iCBT on related symptoms, such as depression, anxiety, and hopelessness, remain unclear. OBJECTIVE: We aimed to analyze whether digital interventions targeting suicidal ideation had an effect on related mental health symptoms (depression, anxiety, and hopelessness). METHODS: We systematically searched CENTRAL, PsycInfo, Embase, and PubMed for randomized controlled trials that investigated guided or unguided iCBT for suicidal ideation or behaviors. Participants reporting baseline suicidal ideation were eligible. Individual participant data (IPD) were collected from eligible trials. We conducted a 1-stage IPD meta-analysis on the effects on depression, anxiety, and hopelessness-analyzed as 2 indices: symptom severity and treatment response. RESULTS: We included IPD from 8 out of 9 eligible trials comprising 1980 participants with suicidal ideation. iCBT was associated with significant reductions in depression severity (b=-0.17; 95% CI -0.25 to -0.09; P<.001) and higher treatment response (ie, 50% reduction of depressive symptoms; b=0.36; 95% CI 0.12-0.60; P=.008) after treatment. We did not find significant effects on anxiety and hopelessness. CONCLUSIONS: iCBT for people with suicidal ideation revealed significant effects on depression outcomes but only minor or no effects on anxiety and hopelessness. Therefore, individuals with comorbid symptoms of anxiety or hopelessness may require additional treatment components to optimize care. Studies that monitor symptoms with higher temporal resolution and consider a broader spectrum of factors influencing suicidal ideation are needed to understand the complex interaction of suicidality and related mental health symptoms.

Transgender Identity and Suicide Attempts and Mortality in Denmark.

Importance: Prior studies have suggested that transgender individuals may be a high-risk group with respect to suicide attempt and mortality, but large-scale, population-based investigations are lacking. Objective: To examine in a national setting whether transgender individuals have higher rates of suicide attempt and mortality than nontransgender individuals. Design, Setting, and Participants: Nationwide, register-based, retrospective cohort study on all 6 657 456 Danish-born individuals aged 15 years or older who lived in Denmark between January 1, 1980, and December 31, 2021. Exposure: Transgender identity was determined through national hospital records and administrative records of legal change of gender. Main Outcomes and Measures: Suicide attempts, suicide deaths, nonsuicidal deaths, and deaths by any cause during 1980 through 2021 were identified in national hospitalization and causes of death registers. Adjusted incidence rate ratios (aIRRs) with 95% CIs controlling for calendar period, sex assigned at birth, and age were calculated. Results: The 6 657 456 study participants (50.0% assigned male sex at birth) were followed up during 171 023 873 person-years. Overall, 3759 individuals (0.06%; 52.5% assigned male sex at birth) were identified as transgender at a median age of 22 years (IQR, 18-31 years) and followed up during 21 404 person-years, during which 92 suicide attempts, 12 suicides, and 245 suicide-unrelated deaths occurred. Standardized suicide attempt rates per 100 000 person-years were 498 for transgender vs 71 for nontransgender individuals (aIRR, 7.7; 95% CI, 5.9-10.2). Standardized suicide mortality rates per 100 000 person-years were 75 for transgender vs 21 for nontransgender individuals (aIRR, 3.5; 95% CI, 2.0-6.3). Standardized suicide-unrelated mortality rates per 100 000 person-years were 2380 for transgender vs 1310 for nontransgender individuals (aIRR, 1.9; 95% CI, 1.6-2.2), and standardized all-cause mortality rates per 100 000 person-years were 2559 for transgender vs 1331 for nontransgender individuals (aIRR, 2.0; 95% CI, 1.7-2.4). Despite declining rates of suicide attempts and mortality during the 42 years covered, aIRRs remained significantly elevated in recent calendar periods up to and including 2021 for suicide attempts (aIRR, 6.6; 95% CI, 4.5-9.5), suicide mortality (aIRR, 2.8; 95% CI, 1.3-5.9), suicide-unrelated mortality (aIRR, 1.7; 95% CI, 1.5-2.1), and all-cause mortality (aIRR, 1.7; 95% CI, 1.4-2.1). Conclusions and Relevance: In this Danish population-based, retrospective cohort study, results suggest that transgender individuals had significantly higher rates of suicide attempt, suicide mortality, suicide-unrelated mortality, and all-cause mortality compared with the nontransgender population.

Nordic region suicide trends 2000-2018; sex and age groups.

BACKGROUND AND AIM: Overall, suicide rates in the Nordic region, Denmark, Finland, Iceland, Norway and Sweden, have declined in the past 40 years. The aim of this study was to determine trends in suicide mortality from 2000 to 2018. METHODS: Data were obtained from official suicide statistics for men and women, 15 years and older. Gender and age groups in four calendar periods were analyzed using Joinpoint Estimated Regression Coefficient. RESULTS: The crude regional suicide rate was 17.1, 2000-2004, decreased to 14.1 per 100,000 inhabitants in 2015-2018. Age-standardized rates are 13.6-11.3. The crude rate decreased by 19.5% (16.3% age-standardized), 19.3% for males and 20.5% for females. The largest decrease was found in Finland (34.9%), the smallest in Norway (1.4%). In males, the exception was an increased suicide rate among all Icelandic except 15-24-year olds, and in 45-64 year-old Norwegians. Among females, an increase was seen among 15-24-year olds in all countries except Iceland, in all age groups in Norway, and in 25-44-year olds in Sweden. In males, a decline of the suicide rated lower than 10% was noted in 25-44 olds in Norway and in 15-64 year-olds in Sweden. DISCUSSION: A robust decrease was observed in the overall regional suicide rate in recent years. Exceptions are rising rates in Icelandic males, in Norwegian females, and the youngest female groups in all except Iceland. The small decline among middle-aged males in Norway and Sweden is of concern.

School performance and genetic propensities for educational attainment and depression in the etiology of self-harm: a Danish population-based study.

BACKGROUND: Poor school performance is linked to higher risks of self-harm. The association might be explained through genetic liabilities for depression or educational attainment. We investigated the association between school performance and self-harm in a population-based sample while assessing the potential influence of polygenic risk scores (PRSs) for depression (PRSMDD) and for educational attainment (PRSEDU). METHOD: We conducted a follow-up study of individuals born 1987-98 and followed from age 18 until 2016. The total sample consisted of a case group (23,779 diagnosed with mental disorders; schizophrenia, bipolar disorder, depression, autism, and attention deficit hyperactivity disorder (ADHD) and a randomly sampled comparison group (n = 10,925). Genome-wide data were obtained from the Neonatal Screening Biobank and information on school performance, family psychiatric history, and socioeconomic status from national administrative registers. RESULTS: Individuals in the top PRSMDD decile were at higher self-harm risk in the case group (IRR: 1.30; 95% CI 1.15-1.46), whereas individuals in the top PRSEDU decile were at lower self-harm risk (IRR: 0.63; 95% CI: 0.55-0.74). Poorer school performance was associated with higher self-harm risk in persons diagnosed with any mental disorder (IRR: 1.69; 95% CI: 1.44-1.99) and among the comparison group (IRR: 7.93; 95% CI: 4.47-15.18). Observed effects of PRSMDD and PRSEDU on self-harm risk were strongest for individuals with poor school performance. CONCLUSION: Associations between PRSMDD and self-harm risk and between PRSEDU and self-harm risk were found. Nevertheless, these polygenic scores seem currently of limited clinical utility for identifying individuals at high self-harm risk.

Effectiveness of medical treatment for bipolar disorder regarding suicide, self-harm and psychiatric hospital admission: between- and within-individual study on Danish national data.

BACKGROUND: Mood stabilisers are the main treatment for bipolar disorder. However, it is uncertain which drugs have the best outcomes. AIMS: To investigate whether rates of suicide, self-harm and psychiatric hospital admission in individuals with bipolar disorder differ between mood stabilisers. METHOD: A cohort design was applied to people aged ≥15 years who were diagnosed with bipolar disorder and living in Denmark during 1995-2016. Treatment with lithium, valproate, other mood stabilisers and antipsychotics were compared in between- and within-individual analyses, and adjusted for sociodemographic characteristics and previous self-harm. RESULTS: A total of 33 337 individuals with bipolar disorder were included (266 900 person-years). When compared with individuals not receiving treatment, those receiving lithium had a lower rate of suicide (hazard ratio 0.40, 95% CI 0.31-0.51). When comparing treatment and non-treatment periods in the same individuals, lower rates of self-harm were found for lithium (hazard ratio 0.74, 95% CI 0.61-0.91). Lower rates of psychiatric hospital admission were found for all drug categories compared with non-treatment periods in within-individual analyses (P<0.001). The low rates of self-harm and hospital admission for lithium in within-individual analyses were supported by results of between-individual analyses. CONCLUSIONS: Lithium was associated with lower rates of suicide, self-harm and psychiatric hospital readmission in all analyses. With respect to suicide, lithium was superior to no treatment. Although confounding by indication cannot be excluded, lithium seems to have better outcomes in the treatment of bipolar disorder than other mood stabilisers.

Intergenerational transmission of suicide attempt in a cohort of 4.4 million children.

BACKGROUND: The association between suicide attempts (SAs) in parents and children is unclear, and risk indicators for intergenerational transmission remain undocumented. We aimed to assess this association, considering the child's developmental period at the time of parents' attempted suicide, and the parental relation. METHODS: Using a prospective cohort design, nationwide population data were linked to the Psychiatric Central Register and National Patient Register for all individuals aged 10 years or older living in Denmark between 1980 and 2016. We assessed incidence rate ratios (IRRs) and cumulative hazards for children's first SA. RESULTS: In a cohort of 4 419 651 children, 163 056 (3.7%) had experienced a parental SA. An SA was recorded among 6996 (4.3%) of the exposed children as opposed to 70112 (1.6%) in unexposed individuals. Higher rates were noted when a parental SA occurred during early childhood (0 ⩽ age < 2) [IRR, 4.7; 95% confidence interval (CI) 4.2-5.4] v. late childhood (6 ⩽ age < 13) (IRR, 3.6; 95% CI 3.4-3.8) when compared to those unexposed. Children exposed prior to age 2 had the highest rates of all sub-groups when reaching age 13-17 (IRR, 6.5; 95% CI 6.0-7.1) and 18-25 years (IRR, 6.8; 95% CI 6.2-7.4). Maternal SA (IRR, 3.4; 95% CI 3.2-3.5) was associated with higher rates than paternal (IRR, 2.8; 95% CI 2.7-2.9). CONCLUSION: Parental SA was associated with children's own SA. Exposure during early developmental stages was associated with the highest rates. Early preventive efforts are warranted as is monitoring of suicide risk in the children from age 13.

Hospital-diagnosed sleep disorders and incident dementia: a nationwide observational cohort study.

BACKGROUND AND PURPOSE: Several smaller, community-based studies have suggested a link between sleep disorders and dementia with a focus on sleep as a modifiable risk factor for dementia. Studies on neurodegenerative diseases are prone to reverse causation, and few studies have examined the association with long follow-up time. Our aim was to explore the possible association between sleep disorders and late-onset dementia in an entire population. METHODS: In a nationwide cohort with 40-year follow-up, associations between hospital-based sleep disorder diagnoses and late-onset dementia were assessed. Incidence rate ratios (IRR) were calculated using Poisson regression. RESULTS: The cohort consisted of 1,491,276 people. Those with any sleep disorder had a 17% higher risk of dementia (IRR 1.17, 95% confidence interval [CI] 1.11-1.24) compared to people with no sleep disorder, adjusted for age, sex, calendar year, highest attained educational level at age 50, and somatic and psychiatric comorbidity. The risk of dementia was significantly increased 0-5 years after sleep disorder diagnosis (IRR 1.35, 95% CI 1.25-1.47), whilst the association after 5 years or more was non-significant (1.05, 95% CI 0.97-1.13). CONCLUSIONS: Our findings show an increased short-term risk of dementia following a hospital-based sleep disorder diagnosis, whilst weaker evidence of a long-term risk was found. This could potentially point towards sleep disorders as an early symptom of dementia. Further research is needed to distinguish sleep disorders as an early symptom of dementia, a risk factor, or both.

Direct costs of hospital care of self-harm: A national register-based cohort study.

OBJECTIVE: To estimate national direct hospital costs associated with treatment of self-harm and to analyse whether costs differ with respect to demographic and clinical characteristics. METHODS: A cohort design was applied to register data on all people living in Denmark (5.8 million inhabitants) from Jan 1, 2012 to Dec 31, 2016. Self-harm presentations at all hospitals by persons aged 10 years and older were included. Total costs and costs related to somatic and psychiatric care and treatment setting (inpatient, emergency department and outpatient) were calculated (in US dollars). The association between specific characteristics and somatic inpatient costs was analysed adjusted using generalized linear models and expressed as Odds Ratios (OR). RESULTS: In all, 42,634 (97.3%) self-harm presentations by 30,366 persons were included. Annual somatic and psychiatric costs amounted to $25,241,518 and $34,696,388, respectively, and the median cost per episode was $2248 (IQR: $1553-$4138). Predictors of high somatic inpatient costs were: admission to intensive care (OR = 15.6; 95% CI, 13.7-17.9), particularly dangerous methods of self-harm, such as being hit by moving objects (OR = 6.5; 95% CI, 2.7-15.7) and shooting (OR = 6.0; 95% CI, 3.4-10.7), and age ≥75 years (OR = 1.8; 95% CI, 1.5-2.2). A small group of persons (0.7%) with ≥10 presentations accounted for 8.2% of somatic and 15.3% of total hospital costs. CONCLUSION: Substantial hospital costs were noted for inpatient treatment. Although one-time presenters accounted for the major share of costs, smaller patient groups accounted for considerable shares. Hospital costs of self-harm should be included in evaluation of initiatives for prevention and treatment.

Proportion of suicides in Denmark attributable to bereavement by the suicide of a first-degree relative or partner: Nested case-control study.

OBJECTIVE: To provide the first estimates of the risk of suicide after bereavement by the suicide of any first-degree relative and the proportion of suicides in Denmark attributable to suicide bereavement. METHODS: We conducted a nationwide nested case-control study defining cases as all Danish-born individuals who died by suicide in Denmark between 01 January 1980 and 31 December 2016 (n = 32,248), age-matched to four living controls. Using three exposure categories (bereavement by the suicide of a relative [parent, offspring, sibling, and spouse/cohabitee]; non-suicide bereavement; no bereavement) and conditional logistic regression adjusted for pre-specified covariates we estimated the odds of exposure to suicide bereavement in cases versus controls. We tested whether associations differed for men and women, estimated the population attributable fraction (PAF) of suicides in our population at risk that could be attributed to a first-degree relative's suicide loss, and estimated the attributable fraction among the exposed (AFe). RESULTS: Suicide bereavement was associated with an increased odds of suicide when compared with no bereavement (ORadj2  = 2.90, 95% CI: 2.46-3.40) or non-suicide bereavement (ORadj2  = 1.48, 95% CI: 1.25-1.74). There was no evidence to support any interaction with sex. PAF (0.69%; 95% CI: 0.62%-0.77%) and AFe (60.12%; 95% CI: 53.19%-66.03%) estimates suggested that in Denmark 0.69% of suicides, and 60% of suicides among suicide-bereaved relatives, could be prevented if it was possible to address all factors increasing suicide risk in suicide-bereaved relatives. CONCLUSION: Suicide bereavement in relatives and partners contributes to at least one in 145 suicides in Denmark.

Safety planning-type interventions for suicide prevention: meta-analysis.

BACKGROUND: Safety planning-type interventions (SPTIs) for patients at risk of suicide are often used in clinical practice, but it is unclear whether these interventions are effective. AIMS: This article reports on a meta-analysis of studies that have evaluated the effectiveness of SPTIs in reducing suicidal behaviour and ideation. METHOD: We searched Medline, EMBASE, PsycINFO, Web of Science and Scopus from their inception to 9 December 2019, for studies that compared an SPTI with a control condition and had suicidal behaviour or ideation as outcomes. Two researchers independently extracted the data. To assess suicidal behaviour, we used a random-effects model of relative risk based on a pooled measure of suicidal behaviour. For suicidal ideation, we calculated effect sizes with Hedges' g. The study was registered at PROSPERO (registration number CRD42020129185). RESULTS: Of 1816 unique abstracts screened, 6 studies with 3536 participants were eligible for analysis. The relative risk of suicidal behaviour among patients who received an SPTI compared with control was 0.570 (95% CI 0.408-0.795, P = 0.001; number needed to treat, 16). No significant effect was found for suicidal ideation. CONCLUSIONS: To our knowledge, this is the first study to report a meta-analysis on SPTIs for suicide prevention. Results support the use of SPTIs to help preventing suicidal behaviour and the inclusion of SPTIs in clinical guidelines for suicide prevention. We found no evidence for an effect of SPTIs on suicidal ideation, and other interventions may be needed for this purpose.

Genetics of suicide attempts in individuals with and without mental disorders: a population-based genome-wide association study.

Family studies have shown an aggregation of suicidal behavior in families. Yet, molecular studies are needed to identify loci accounting for genetic heritability. We conducted a genome-wide association study and estimated single nucleotide polymorphisms (SNP) heritability for a suicide attempt. In a case-cohort study, national data on all individuals born in Denmark after 1981 and diagnosed with severe mental disorders prior to 2013 (n = 57,377) and individuals from the general population (n = 30,000) were obtained. After quality control, the sample consisted of 6024 cases with an incidence of suicide attempt and 44,240 controls with no record of a suicide attempt. Suggestive associations between SNPs, rs6880062 (p-value: 5.4 × 10-8) and rs6880461 (p-value: 9.5 × 10-8), and suicide attempt were identified when adjusting for socio-demographics. Adjusting for mental disorders, three significant associations, all on chromosome 20, were identified: rs4809706 (p-value: 2.8 × 10-8), rs4810824 (p-value: 3.5 × 10-8), and rs6019297 (p-value: 4.7 × 108). Sub-group analysis of cases with affective disorders revealed SNPs associated with suicide attempts when compared to the general population for gene PDE4B. All SNPs explained 4.6% [CI-95: 2.9-6.3%] of the variation in suicide attempt. Controlling for mental disorders reduced the heritability to 1.9% [CI-95: 0.3-3.5%]. Affective and autism spectrum disorders exhibited a SNP heritability of 5.6% [CI-95: 1.9-9.3%] and 9.6% [CI-95: 1.1-18.1%], respectively. Using the largest sample to date, we identified significant SNP associations with suicide attempts and support for a genetic transmission of suicide attempt, which might not solely be explained by mental disorders.

Physical, mental, and social wellbeing and their association with death by suicide and self-harm in older adults: a community-based cohort study.

OBJECTIVE: To assess associations between physical, mental, and social well-being and suicide and self-harm in a community-based sample of older adults. METHODS: Using a cohort design, questionnaire data from 102,880 individuals aged 65 years or older living in New South Wales, Australia during 2006-2009 were linked to hospital and cause-of-death databases until 2017. Poisson regressions obtained adjusted incidence rate ratios (IRRs). RESULTS: One hundred nine suicides and 191 deliberate self-harm (DSH) events occurred. Compared to those reporting excellent/good overall health, older adults reporting fair overall health had higher suicide rates (IRR = 2.8, 95% confidence interval: 1.8-4.4). Also, suffering from physical limitations was associated with higher rates of suicide. A fair versus excellent/good memory was associated with higher rates of suicide (IRR = 2.0, 1.3-3.3). Male erectile dysfunction was linked to self-harm (IRR = 2.8, 1.0-7.7). Suicide rates were elevated with baseline Kessler-10 scores of 20-50 versus 10-15 (IRR = 5.0, 2.9-8.9); the corresponding IRR for DSH was 2.9 (1.8-4.8). Elevated rates were observed for both self-reported depression and anxiety. Poor versus excellent/good quality of life was associated with suicide (IRR = 4.3, 1.7-10.7) and achieving less than desired to due to emotional problems was linked to self-harm (IRR = 1.8 1.3-2.4). Rates of suicide ande DSH were lower in those with ≥5 people to depend on versus one (suicide: IRR = 0.5, 0.3-0.9; DSH: IRR = 0.5, 0.3-0.7). CONCLUSIONS: Older adults experiencing health problems, including those relating to overall health or memory, and those with psychological distress had elevated rates of suicidal behavior. Rates of subsequent self-harm and/or death by suicide were elevated in participants with small social networks.