There has been a proliferation of studies on the correlates of hedonic well-being, and several psychosocial variables have been identified as risk and protective factors. However, individuals are not randomly exposed to psychosocial variables. Instead, individuals select into and evoke responses from psychosocial variables based on their genetic predispositions (i.e. active and evocative gene-environment correlation). Consequently, overlap between psychosocial exposures and hedonic well-being may not reflect environmental influence alone. Rather, if individuals are assorted into exposures based partly on their genetic predispositions, then associations between psychosocial exposures and hedonic well-being may be undergirded by both genetic and environmental factors.
The aims of the present study were as follows: (1) Using a large population-representative sample of adults, estimate the degree of concurrent and longitudinal overlap between psychosocial exposures measured at midlife and hedonic well-being measured at midlife and later adulthood. (2) Using a subsample of identical and fraternal twins, test for the presence of heritable variation in psychosocial exposures- i.e. test for gene-environment correlation. (3) After accounting for gene-environment correlation, estimate the degree of overlap between psychosocial exposures and hedonic well-being.
The sample included adults ((N > 7,000; mean age ~ 45 years) and a subsample of twins (N > 1,800) who took part in the National Survey of Midlife Development in the United States (MIDUS). Data collection first took place between 1995-1996. The second wave of the study took place a decade later, between 2004-2006 (N = 4963). Retention rates for the full sample and twin subsample were high (~ 70% and 78%, respectively). Hedonic well-being was measured using self-reports of positive affect, negative affect, and general life satisfaction. Twelve psychosocial variables were also measured using self-reports: maternal affection, paternal affection, maternal discipline, paternal discipline, family strain, family support, friendship strain, friendship support, spouse stain, spouse support, positive work-to-family spillover, and negative work-to-family spillover.
Results of bivariate confirmatory factor analysis models found small-to-moderate overlap (mean r = .21, range = .07 to .52) between psychosocial exposures measured at midlife and hedonic well-being measured at midlife and later adulthood. In addition, quantitative genetic models provided evidence that psychosocial exposures were heritable (mean h2 = .34, range = .18 to .58); After accounting for these genetic confounds, the degree of overlap between psychosocial exposures and hedonic well-being was negligible-to-small (mean r = .10, range = -.03 to .28). Thus, the present study showed that associations between psychosocial exposures and hedonic well-being reflect, in part, overlapping genetic predispositions. Nevertheless, with the exceptions of maternal and paternal discipline, even after accounting for gene-environmental correlation, the associations between psychosocial exposures and hedonic well-being remained significantly different than zero. This provided evidence for a quasi-causal effect of psychosocial exposures on hedonic well-being, albeit of small magnitude.
