Neuroticism, life events and mental health: evidence for person-environment correlation

There is some evidence that genetic effects on the likelihood of experiencing stressful life events (SLEs) are mediated by heritable traits such as cognitive ability (CA) and neuroticism (N).

To examine whether the association between CA, N and mental ill-health is driven in part by a predisposition to experience depressogenic SLEs.

Childhood measures of N and CA were available in a birth cohort of 5362 individuals. At ages 36 and 43 years, mental state and occurrence of SLEs in the previous year were assessed. Using a path-analytic approach, models with and without a hypothesised influence of N and CA on the occurrence of SLEs were compared.

The fit of the model with childhood N having a direct influence on SLEs was good with chi 2 = 5.72, d.f. = 4, P = 0.22 at age 36 years and chi 2 = 3.50, d.f. = 5, P = 0.62 at age 43. The fit of the model was significantly worse without this path at both ages (36 years: chi 2 = 42.5, d.f. = 1, P < 0.001; 43 years chi 2 = 15.3, d.f. = 1, P < 0.001). No consistent differences were seen in comparisons of models with CA.

The results are congruent with the suggestion that genetic effects on SLEs are mediated by personal characteristics. Part of the well-established association between N and minor psychiatric disorder may be mediated by an indirect effect of N on the likelihood of experiencing SLEs.