Longitudinal data from a community study of 9900 adults in the United States show that persons with depressive symptoms, as compared to those without such symptoms, were 4.4 times more likely to develop a first onset major depression over one year. The attributable risk, a measure which reflects both the relative risk associated with depressive symptoms (4.4) and the prevalence of exposure to that risk (24%) and is a useful measure for documenting burden of a risk to the community, indicated that more than 50% of first onset major depressions are associated with prior depressive symptoms. Since depressive symptoms have a high prevalence in the community, but are often unrecognized and untreated in clinical practice, we conclude that their identification and the development of effective treatments could have public health implications for the prevention of associated social morbidity, service utilization and major depression.
