Self-rated health and mortality: family background and genetic precursors

Self-rated health (SRH) strongly predicts future mortality, even after controlling for various confounding factors. This study investigates two potential confounders of the SRH/mortality relationship-shared family background and genetics.

We analyze a dataset of several harmonized twin studies from the integrating genes and environment from multiple studies consortium. Utilizing a within-between twin methodology, we assess whether the SRH/mortality relationship can be explained by social and genetic inheritance.

Our within-twin estimates are notably lower than the observational estimates, although the difference is statistically non-significant, indicating no substantial confounding from family background. Additionally, we find no significant interaction effects by zygosity, suggesting no confounding from shared genetic factors.

SRH has been shown to be robust to multiple sources of variation, including demographic sub-groups and contemporary controls for clinical assessments. This study reaffirms the resilience of the SRH/mortality relationship against confounding from shared family background and genetic factors.