Depressive Symptoms and Onset of Functional Disability Over 2 Years: A Prospective Cohort Study

OBJECTIVES This prospective cohort study examined the relationship between depressive symptoms and onset of functional disability over 2 years among US Chinese older adults, a rapidly growing minority older adult population. DESIGN AND SETTING This study used survey data from 2713 Chinese older adults who completed both baseline (2011-2013) and follow-up (2013-2015) interviews of the Population Study of Chinese Elderly in Chicago. Depressive symptoms were assessed at baseline by the nine-item Patient Health Questionnaire. Functional disability was measured by three validated scales, Katz Index of Independence in Activities of Daily Living (ADLs), the Lawton Instrumental Activities of Daily Living (IADLs) scale, and the Rosow and Breslau mobility scale. Multivariate logistic regression was conducted to examine the relationship between baseline depressive symptoms and the development of functional disability (ADLs, IADLs, mobility) at 2-year follow-up while adjusting for covariates. RESULTS Of the 2713 participants, 5.2% experienced ADL disability onset, 35.6% experienced IADL disability onset, and 23.3% experienced mobility disability onset over 2 years. After adjusting for covariates, the odds of ADL disability onset (odds ratio [OR] = 1.06; 95% confidence interval [CI] = 1.02-1.11), IADL disability onset (OR = 1.05; 95% CI = 1.01-1.09), and mobility disability onset (OR = 1.05; 95% CI = 1.01-1.09) were consistently higher in US Chinese older adults with higher levels of depressive symptoms than their less-depressed counterparts. Other significant risk factors included older age and more chronic physical conditions. CONCLUSION Study findings underscore a significant relationship between depressive symptoms and onset of functional disability. Screening and, subsequently, treating depressive symptoms have the potential to reduce disability among US Chinese older adults. Culturally relevant depressive symptom screening may help identify Chinese older adults who are at greater risks for the development of functional disability. J Am Geriatr Soc 67:S538-S544, 2019.