The Reciprocal Relationship Between Depression and Physical Morbidity: The Role of Subjective Age

Objectives: The study aims to examine whether the reciprocal effects of physical morbidity and depression are moderated by subjective age-that is, individuals' perception of themselves as young or old. Method: Data from the first two waves of the Midlife in the United States study (1995-6, T1; 2004-6, T2; http://midus.wisc.edu/) were analyzed using a cross-lagged design. We assessed 3,591 individuals who participated in both waves and provided full data on all the relevant variables (mean age at T1 = 47.4). Depression and the number of chronic illnesses (the indicator of physical morbidity) were measured at both waves and were tested as predictors and outcomes in a cross-lagged model. The moderating role of subjective age was assessed by examining whether T1 variables interacted with subjective age in predicting T2 outcomes. Results: Subjective age moderated the T1 depression-T2 morbidity relationship, so that the relationship was stronger for those with older subjective age. Subjective age did not moderate the T1 morbidity-T2 depression relationship. Conclusion: Older subjective age could be a risk factor for experiencing greater physical morbidity following depression.