Vulnerability factors for common mental illnesses

Abstract

Background: Twin studies suggest that shared early family environment is of only minor importance in the aetiology of depression, most of the variance being attributable either to genetic or to individual 'non-shared' environmental factors. Aims: To examine the respective roles of personality and social experiences on the risk for common mental disorders, with special reference to depression. Method: Analysis of preliminary findings from two large-scale British population surveys: (a) a multi-centre study of general practice patients, and (b) a study of working- class women in Manchester. Results: (a) Persons recently separated from their partners have raised mean scores for psychological distress, but the relative excess is due entirely to persons with high ratings for introversion; (b) while severe life events were associated with physiological responses characteristic of depression, the probability of experiencing such life events varied between 0.2 monthly for low scorers and 1.5 monthly for high scorers on a vulnerability measure. Conclusions: Social factors do appear to influence the prevalence of depression, but this effect is not independent of genetically determined vulnerability. Declaration of interest: None.