Genetically informative analysis of the association between intimate relationship adjustment and health

Prior research has found a positive association between the quality or adjustment of an individual's intimate relationship, such as marriage, and their physical health. However, it is possible that this association may be due, at least in part, to confounding variables (i.e., variables that are causally associated both with relationship adjustment and health and could account for their covariation), including genetically influenced confounds. This study was conducted using a genetically informative sample of twins to examine the association between intimate relationship adjustment and self-rated health, accounting for unmeasured genetic and environmental confounds.

A Swedish sample of 539 monozygotic and dizygotic twins (321 male twin pairs and 218 female twin pairs) and their spouse or long-term partner completed self-report measures of relationship adjustment and health.

Relationship adjustment was positively associated with self-rated health in male and female twins. For male twins, nonshared environmental influences largely accounted for the association between relationship adjustment and health; for female twins, this association was generally explained by shared and nonshared environmental influences. For male twins, results obtained from partners' reports of relationship adjustment were largely consistent with those obtained from twins' reports.

Results suggest that the association between relationship adjustment and self-rated health remains after accounting for shared genetic influences, and that nonshared environmental influences, such as partners' characteristics, account for the association between relationship adjustment and self-rated health in men. (PsycInfo Database Record (c) 2021 APA, all rights reserved).