Background Children whose parents die by, or attempt, suicide are believed to be at greater risk of suicidal behaviours and affective disorders. We systematically reviewed the literature on the association of parental fatal and non-fatal suicidal behaviours with offspring suicidal behaviour and depression and, using meta-analysis, estimated the strength of these associations. We further investigated the role of parental and offspring gender, and offspring age at exposure as potential effect modifiers.

Methods We carried out a comprehensive literature search using Medline (1950-April 2011), PsycINFO (1876-April 2011), EMBASE (1980-April 2011) and Web of Science. Twenty eight articles met our inclusion criteria, 14 of which contributed to the meta-analysis. Crude odds ratio (OR) and adjusted odds ratio (AOR) were pooled using fixed-effects models.

Results Controlling for relevant confounders, offspring whose parents died by suicide were more likely than offspring of two living parents to die by suicide [AOR 1.94, 95% confidence interval (CI) 1.54–2.45] but there were heterogeneous findings in the two studies investigating the impact of parental suicide on offspring suicide attempt (AOR 1.31, 95% CI 0.73–2.35). Children whose parents attempted suicide were more likely than unexposed children to attempt suicide (AOR 1.95, 95% CI 1.48–2.57). However, compared with offspring of parents who died by other causes, the risk of suicidal behaviour was only slightly elevated for offspring of suicide decedents (suicide: OR 1. 81, 95% CI 1.56–2.10; suicide attempt: OR 1.73, 95% CI 1.63–1.83); no adjusted analyses were available. Limited published research indicated that offspring exposure to parental death by suicide is associated with subsequent increased risk of affective disorders compared to offspring of two living parents. Maternal suicidal behaviour was associated with larger effect estimates compared to paternal suicidal behaviours. There was some evidence that younger age at exposure to parental suicidal behaviours was associated with greater risk than exposure in later childhood/adolescence. There was no evidence that the association differed in sons versus daughters.

Conclusion Parental suicidal behaviour is associated with increased risk of offspring suicidal behaviour, above and beyond the risk associated with a loss of a parent to a cause other than suicide. Findings suggest that maternal suicidal behaviour is a more potent risk factor than paternal suicidal behaviour. Limited evidence suggests that children are more vulnerable than adolescents and adults. However, there is no evidence of a stronger association in either male or female offspring.