Background: Epidemiologic and clinical studies have established an association between major depression and arteriosclerotic heart disease. It is not certain whether depression increases risk for heart disease or vice versa. We utilized a twin design to test whether there are common genetic and environmental risk factors that overlap both conditions. We then estimated the magnitude of common genetic and/or environmental risk factors. Methods: Subjects were 2,634 male-male twin pairs from the Vietnam Era Twin Registry who responded to both a 1990 health survey and a 1992 telephone administration of the Diagnostic Interview Schedule, Version 3, Revised. Genetic model fitting was performed to determine if heart disease and symptoms of depression are due to common genetic and/or environmental factors. Results: Under the full bivariate model, genes accounted for 61.7% (95% CI: 2.7-82.8) and 36.5% (95% CI: 20.2-41.9%) of the variance in risk for heart disease and depression symptoms, respectively. Due to broad confidence intervals, the magnitude of the genetic influence to heart disease is imprecise. But models that did not allow for a genetic correlation between the two disorders provided a poor fit to the data. The genetic correlation was substantial (r = 0.43; 95% CI: 0.18-0.1.0). We were unable to reject a role for shared environmental influences to heart disease. Conclusions: Our results suggest the co-occurrence of heart disease and depression symptoms in middle aged male twin pairs is partly due to a modest common genetic vulnerability.
|Number of pages||1|
|Journal||American Journal of Medical Genetics - Neuropsychiatric Genetics|
|State||Published - Oct 8 2001|