Familial transmission of suicidal behavior

Abstract

Adoption and twin studies show that familial transmission of suicidal behavior is partly attributable to genetic factors. Transmission of suicidal behavior is mediated by transmission of impulsive aggression or neuroticism and neurocognitive deficits. The most plausible explanations for nongenetic familial transmission are the intergenerational transmission of abuse and adverse familial environments. Bereavement and relationship disruption contribute to suicidal risk via the development of complicated grief, although long-term effects may be mediated by a complex chain of interrelated events. Imitation may contribute to suicidal risk, at least in attempted suicide. However, so-called family environmental factors often are related to risk factors that are heritable. Conversely, genetic factors exert their impact on depression and suicidal behavior via interaction with a stressful environment.

Figures

Figure 1. Risk of Suicide Attempt in the Offspring of Attempters Compared to Offspring of Non-Attempters.*

Diamond = Attempter Square = Nonattempter *From Brent et al. Familial pathways to early-onset suicide attempt: Risk for suicidal behavior in offspring of mood-disordered suicide attempters. Arch Gen Psychiatry 2002; 59:801–807, with permission.

Figure 2. Suicide Attempts Over Time Among Offspring of Mood Disorder Probands From Sibling Pairs Concordant or Discordant for Suicidal Behavior*

Black Circle = Offspring of sibling-concordant suicidal probands Red Diamond = Offspring of sibling-discordant suicidal probands Green Diamond = Offspring of nonsuicidal probands *From Brent et al. Peripubertal suicide attempts in offspring of suicide attempters with siblings concordant for suicidal behavior. Am J Psychiatry 2003; 160:1486–1493, with permission.