Disease as a predictor of depression in aging adults

The purpose of this study is to examine the effects of self-reported chronic health conditions and functional status on the Center for Epidemiologic Studies depression scale using data from the Health and Retirement Study (HRS). The analysis consisted of fitting multivariate adaptive regression splines (MARS) modes to the extant data. Possible covariates included: age, gender, being white, being Hispanic, high blood pressure, heart disease, arthritis, lung disease, back pain, diabetes, stroke, cancer, ADL and IADL functional limitations. Data included 27,461 respondent's longitudinal data, which was collected on eight test occasions. Four hypotheses were formed. Results indicated that back pain and lung disease predicted depression scores which support the second hypothesis. ADL and IADL functional limitations were the most important predictors of depression score, confirming the third and fourth predictions. While chronic disease can lead to elevated depression scores, it appears that functional limitations may be more strongly related to depression.