Research has consistently suggested that offspring of parents with self-harm thoughts and behaviors (STB) are at greater risk for STB themselves. For example, a recent meta-analysis concluded that family history of STB was moderately associated with both offspring suicidal ideation (OR 2.13) and attempts (OR 1.57). However, it is unclear how the risk of STB is transmitted from parent to child, and whether there are protective factors that may modify this association (e.g., peer/family support). Suicidal behavior is known to be heritable, and it is likely that intergenerational effects are driven by a combination of genetic and environmental pathways.

Existing research has tended to be based on small, selected samples, used cross-sectional designs, or used large population-based registries which are limited to those in contact with services. Prior work has also often focused on the impact of parental death by suicide, rather than looking at the range of STB. It has been argued that self-harm is best conceptualized on a continuum of severity, ranging from passive suicidal thoughts to death by suicide and encompassing both suicidal and non-suicidal behaviors (although others argue that suicidal and non-suicidal self-harm are distinct). There is also heterogeneity in the chronicity of STB over time, yet little work has examined whether offspring outcomes differ for different parental phenotypes.

The proposed study will address these knowledge gaps using data from two complementary cohort studies – the Avon Longitudinal Study of Parents and Children (ALSPAC) and the Early Prediction of Adolescent Depression Study (EPAD)