Work

Assortative Mating Across the Full Spectrum of Mental Disorders: A Nationwide Finnish Register Study

Year: 2025

Type: article

Abstract: Background Previous research has shown assortative mating across various psychiatric disorders; however, their definitions of partnership have often been limited, and the timing of relationship formation remains imprecise. This study aims to comprehensively examine assortative mating across the full spectrum of mental disorders, using population-wide register data from Finland that include information on the formation of both marriages and cohabiting unions. Methods We used nationwide data on all cohabitations and marriages between 2000 and 2020 from the Finnish Population Register. Broad and specific categories of mental disorder diagnoses were retrieved from both primary and secondary healthcare registers in Finland. We calculated tetrachoric correlations between partners’ mental disorder diagnoses, considering only diagnoses received before the start of cohabitation or marriage. Results The study included 964,017 men and 957,207 women, forming 1,271,242 partnerships. Assortative mating was observed across the full spectrum of mental disorders, with the strongest within-disorder correlations for schizophrenia, psychotic disorders, organic mental disorders, and intellectual disabilities (r > 0.50). Moderate correlations were found for mood and anxiety disorders. Adjusting for birth decade and excluding comorbidities slightly attenuated the associations but did not change the overall patterns. Conclusions This study suggests that assortative mating is prevalent for mental disorders. These findings suggest that assortative mating may contribute to the transmission and clustering of mental disorders within families, highlighting the importance of considering partner selection in mental health research and policy-making.

Source: Biological Psychiatry Global Open Science

DOI: 10.1016/j.bpsgos.2025.100642

Authors: Kateryna Golovina, Mai Gutvilig, Ripsa Niemi, Christian Hakulinen

Institutions: University of Helsinki, Väestöliitto, Finnish Institute for Health and Welfare

Language: English

Topic: Mental Health Treatment and Access

Subfield: Social Psychology

Field: Psychology

Domain: Social Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,700