Overview
- Published in Nature Human Behaviour, the study tracked nine conditions, including schizophrenia, bipolar disorder, depression, anxiety, ADHD, autism, OCD, substance-use disorder and anorexia nervosa.
- Partners were more likely to share the same diagnosis than to have different psychiatric conditions, a pattern consistent across cultures and birth cohorts from the 1930s to the 1990s.
- The likelihood of partners sharing a diagnosis rose slightly each decade, with the clearest increases seen for substance-use disorders.
- Geographic variation emerged for a few diagnoses, with higher spousal sharing of OCD reported in Taiwan and differing patterns also seen for bipolar disorder and anorexia nervosa.
- Children with two parents who share the same disorder faced about twice the risk of developing it, a trend noted especially for conditions with strong genetic components, while causes remain untested and proposed mechanisms include assortative mating, environmental convergence and stigma-limited partner choice.