Chronic disease and depression among the elderly in China: the mediating role of instrumental activities of daily living and the moderating role of area of residence

Chronic diseases are associated with depressive symptoms in older adults. However, the mechanism of this relation is not clear. In this study, we explored the mediating role of instrumental activities of daily living and the moderating role of area of residence in the relationship between chronic diseases and depression. The data was from the Chinese Longitudinal Healthy Longevity Study. Results showed that chronic diseases were positively correlated with depression, and negatively associated with instrumental activities of daily living (IADLs). Moreover, IADLs mediated the relationship between chronic diseases and depression. In addition, area of residence (rural/urban) moderated the relation between IADLs and depression, such that this negative relation was stronger for old adults lived in rural area than for urban area. These results have important significance for prevention and intervention of depression in the elderly.