A Twin Study on the Relation Between Positive Mental Health and Biological Aging

Positive mental health (PMH) has recently become a key topic in biomedical research. Previous studies have explored the correlation between biological and psychological measures, but only a few have focused on the relationship between PMH and aging. This study aimed: (i) to explore the association between PMH and biological aging; (ii) to determine if and to what extent the observed association could be explained by shared genetic and environmental effects. A total of 401 twins (age 19-81 years, 32% male) from the Italian Twin Registry were recruited, and the twin study design was applied. A self-report psychological test battery was used to evaluate several PMH components. Blood samples were collected from participants to determine telomere length (TL) and mitochondrial DNA copy number (mtDNAcn). TL was negatively associated with attachment anxiety (r = -0.11, p = 0.037). A bivariate twin model provided heritability estimates of 0.14 (95% CI 0.001-0.43) for TL and 0.32 (0.16-0.45) for attachment anxiety, and a substantial negative genetic correlation [r_g = -0.55 (-1.00-0.00)] between them. Under the limitations of a cross-sectional study with a self-report wellbeing assessment, these results suggest that anxiety in the relationship with a partner may contribute to accelerated TL shortening, and shared genetic factors may underlie this link.