Research Finds Consistent Spousal Similarities in Nine Psychiatric Disorders Across Generations

A comprehensive international study has revealed that spouses tend to show notable similarities across nine psychiatric conditions, and these patterns remain consistent over multiple generations and across diverse cultures. Analyzing data from over 14 million individuals in Taiwan, Denmark, and Sweden, the researchers observed persistent spousal resemblance patterns lasting for roughly 90 years. The study provides evidence that these similarities are not limited to specific regions and are evident across different societal contexts.

Previous smaller-scale investigations had indicated that couples often share certain psychiatric traits and disorders. However, this large-scale, population-based research aimed to determine the extent and stability of these patterns on a global and generational scale.

The analysis included approximately five million spousal pairs in Taiwan, over half a million in Denmark, and more than 700,000 in Sweden, covering a broad demographic spectrum. The disorders examined ranged from major depressive disorder, bipolar disorder, and schizophrenia to conditions like anorexia nervosa, obsessive-compulsive disorder, and substance use disorders. The findings demonstrated that in Taiwanese couples, there was a positive association across all disorder pairs, resembling patterns seen in Nordic countries, although some differences existed—for example, in anorexia nervosa and bipolar disorder.

Importantly, the study observed that these patterns persisted across birth cohorts, with certain disorders like substance use increasing in spouses over time, while others such as obsessive-compulsive disorder declined. Additionally, offspring of couples where both parents were diagnosed with a psychiatric disorder had a higher risk of developing similar conditions, emphasizing the genetic and environmental interplay involved.

The genetic analyses aligned with these epidemiological findings, showing that genetic heritability and correlations underpinning these disorders are consistent with the observed spousal similarities. The research underscores the importance of considering assortative mating—the tendency for individuals with similar traits to pair up—when studying the inheritance and development of psychiatric conditions.

Overall, this study highlights the complex genetic and social factors influencing psychiatric disorders and suggests that cultural, familial, and biological factors contribute to the observed patterns of spousal resemblance across generations. These insights have important implications for understanding the heritability of mental health conditions and tailoring preventative strategies.

Source: https://medicalxpress.com/news/2025-09-spouses-similarities-psychiatric-disorders-generations.html