Do somatic complaints predict subsequent symptoms of depression?
Evidence suggests substantial comorbidity between symptoms of somatization and depression in clinical as well as nonclinical populations. However, as most existing research has been retrospective or cross-sectional in design, very little is known about the specific nature of this relationship. In particular, it is unclear whether somatic complaints may heighten the risk for the subsequent development of depressive symptoms. We report findings on the link between symptoms of somatization (assessed using the SCL-90-R) and depression 5 years later (assessed using the CES-D) in an initially healthy cohort of community adults, based on prospective data from the RENO Diet-Heart Study. Gender-stratified multiple regression analyses revealed that baseline CES-D scores were the best predictors of subsequent depressive symptoms for men and women. Baseline scores on the SCL-90-R somatization subscale significantly predicted subsequent self-reported symptoms of depressed mood 5 years later, but only in women. However, somatic complaints were a somewhat less powerful predictor than income and age.
Our findings suggest that somatic complaints may represent one, but not necessarily the most important, risk factor for the subsequent development of depressive symptoms in women in nonclinical populations. The results also highlight the importance of including social variables in studies on women's depression as well as conducting additional research to further examine predictors of depressive symptoms in men.