Genetic variances in subjective health are shared with physical health, depressive symptoms, and episodic memory

Understanding the genetic influences on how we perceive our health
Subjective health (SH) is how individuals rate their own health, which can be influenced by physical health, mental health, and cognitive abilities. This study explores how genetics and environment shape these perceptions and whether they differ by age and sex. Data from 10 studies of the Interplay of Genes and Environment across Multiple Studies (IGEMS) consortium were used to study this. This included two NEAR studies: the Swedish Adoption/Twin Study of Aging (SATSA) and a Longitudinal Study of Gender Differences in Health Behavior and Health among Elderly (GENDER). The sample included 24,173 twins ranging in age from 40 to 90 years. Three measures of subjective health were included: self-rated health, health relative to others, and influence of health on daily activities.

Photo: Cecilia Öhlund

Genetic variances in subjective health are shared with physical health, depressive symptoms, and episodic memory
Genetics significantly influences subjective health, with genetic factors explaining 20-46% of the differences in how people rate their health. The remaining differences are primarily due to unique environmental factors. However, most or all genetic variance in subjective health is shared with physical health, depressive symptoms, and episodic memory, indicating that these factors are interconnected.

Older adults (66-90 years) show stronger genetic correlations between subjective health and physical health, depressive symptoms, and episodic memory, compared to middle-aged adults (40-65 years). This suggests that as people age, their perception of health becomes more holistic, integrating various aspects of their well-being. Women tend to have higher heritability estimates for subjective health than men, meaning genetic factors play a larger role in how women perceive their health.

In conclusion, these findings highlight that subjective health reflects physical health and is closely intertwined with mental health and cognitive function. This comprehensive view of health becomes more pronounced with age, suggesting that interventions aimed at improving subjective health should consider these interconnected aspects.

Deborah Finkel, first author of the study.

Publication
Finkel, D., Gatz, M., Franz, C. E., Catts, V. S., Christensen, K., Kremen, W., Nygaard, M., Plassman, B. L., Sachdev, P. S., Whitfield, K., Pedersen, N. L. Age and sex differences in the genetic architecture of measures of subjective health: Relationships with physical health, depressive symptoms, and episodic memory. The Journals of Gerontology, Series B: Psychological Sciences and Social Sciences. 2024; 79(6), gbae062. https://doi.org/10.1093/geronb/gbae062.