Divorce, genetic risk, and suicidal thoughts and behaviors in a sample with recurrent major depressive disorder.

BACKGROUND: Theories of risk for suicidal thoughts and behaviors (STB) implicate both interpersonal and biological factors. Divorce/separation and aggregate genetic liability are robustly associated with STB, but have seldom been evaluated in conjunction with one another. Furthermore, whether these factors are effective predictors in high-risk populations is not clear. METHODS: Analyses were conducted in a sample of Han Chinese women with severe recurrent major depressive disorder (maximum N = 4380). Logistic regressions were used to evaluate the associations between divorce/separation and polygenic scores (PGS) for suicidal ideation or behavior with STB. Where appropriate, additive interactions between divorce and PGS were tested. RESULTS: Divorce/separation was significantly associated with increased risk of suicidal ideation, plans, and attempts (odds ratios = 1.28-1.61). PGS for suicidal ideation were not associated with STB, while PGS for suicidal behavior were associated with ideation and plans (odds ratios = 1.08-1.09). There were no significant interactions between divorce/separation and PGS. CONCLUSIONS: Consistent with theories of suicidality, the disruption or end of an important interpersonal relationship is an indicator of risk for STB. Aggregate genetic liability for suicidal behavior more modestly contributes to risk, but does not exacerbate the negative impact of divorce. Thus, even within a high-risk sample, interpersonal and biological exposures distinguish between those who do and do not experience STB, and could motivate targeted screening. Further research is necessary to evaluate whether and how the context of divorce contributes to variation in its effect on STB risk.

Divorce and risk of suicide attempt: a Swedish national study.

BACKGROUND: Prior research has reported an association between divorce and suicide attempt. We aimed to clarify this complex relationship, considering sex differences, temporal factors, and underlying etiologic pathways. METHODS: We used Swedish longitudinal national registry data for a cohort born 1960-1990 that was registered as married between 1978 and 2018 (N = 1 601 075). We used Cox proportional hazards models to estimate the association between divorce and suicide attempt. To assess whether observed associations were attributable to familial confounders or potentially causal in nature, we conducted co-relative analyses. RESULTS: In the overall sample and in sex-stratified analyses, divorce was associated with increased risk of suicide attempt (adjusted hazard ratios [HRs] 1.66-1.77). Risk was highest in the year immediately following divorce (HRs 2.20-2.91) and declined thereafter, but remained elevated 5 or more years later (HRs 1.41-1.51). Divorcees from shorter marriages were at higher risk for suicide attempt than those from longer marriages (HRs 3.33-3.40 and 1.20-1.36, respectively). In general, HRs were higher for divorced females than for divorced males. Co-relative analyses suggested that familial confounders and a causal pathway contribute to the observed associations. CONCLUSIONS: The association between divorce and risk of suicide attempt is complex, varying as a function of sex and time-related variables. Given evidence that the observed association is due in part to a causal pathway from divorce to suicide attempt, intervention or prevention efforts, such as behavioral therapy, could be most effective early in the divorce process, and in particular among females and those whose marriages were of short duration.

Sibling alcohol use disorder is associated with increased risk for suicide attempt.

The association between having a sibling diagnosed with alcohol use disorder (AUD) and risk for suicide attempt may be attributable to shared genetic liability between AUD and suicidal behavior, effects of environmental exposure to a sibling's AUD, or both. To distinguish between these alternatives, we conducted a series of Cox regression models using data derived from Swedish population-based registers with national coverage. Among full sibling pairs (656,807 males and 607,096 females), we found that proband risk for suicide attempt was significantly elevated when their sibling was affected by AUD, even after accounting for the proband's AUD status. Further, risk for proband suicide attempt was consistently higher when the sibling's AUD registration had occurred more recently. Our findings provide evidence for exposure to sibling AUD as an environmental risk factor for suicide attempt and suggest that clinical outreach may be warranted following a sibling's diagnosis with AUD.