Background: Family studies have suggested that eating disorders and mood disorders may coaggregate in families. To study further this question, data from a family interview study of probands with and without major depressive disorder was examined.
Method: A bivariate proband predictive logistic regression model was applied to data from a family interview study, conducted in Innsbruck, Austria, of probands with (N = 64) and without (N = 58) major depressive disorder, together with 330 of their first-degree relatives.
Results: The estimated odds ratio (OR) for the familial aggregation of eating disorders (anorexia nervosa, bulimia nervosa and binge-eating disorder) was 7.0 (95 % CI 1.4, 28; P = 0.006); the OR for the familial aggregation of mood disorders (major depression and bipolar disorder) was 2.2 (0.92, 5.4; P = 0.076); and for the familial coaggregation of eating disorders with mood disorders the OR was 2.2 (1.1, 4.6; P = 0.035).
Conclusions: The familial coaggregation of eating disorders with mood disorders was significant and of the same magnitude as the aggregation of mood disorders alone--suggesting that eating disorders and mood disorders have common familial causal factors.