Celia F Hybels, PhD¹, Carl F Pieper, DrPH², and Dan G Blazer, MD, PhD, MPH¹. (1) Dept. of Psychiatry and Behavioral Sciences & Center For Aging, Duke University Medical Center, Box 3003, Durham, NC 27710, (919) 660-7546, cfh@geri.duke.edu, (2) Dept. of Biostatistics and Bioinformatics & Center For Aging, Duke University Medical Center, Box 3003, Durham, NC 27710

In longitudinal studies, scores of 16+ on the CES-D have been shown to be associated with functional decline in older adults. Less is known about the impact of subthreshold depression on functional status. Using data from four waves of the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE), we employed a mixed model repeated measures design to predict subsequent functional status by depression status. Depression was measured by the CES-D. Two depression variables were included in each model, a variable for subthreshold depression equivalent to a score of 11+ and a variable equivalent to a score of 16+ to measure the incremental effect of CES-D defined depression. Functional status was assessed at the subsequent wave using three measures: Katz ADL, Rosow-Breslau mobility, and OARS IADL. Controlling for race, sex, age, education, marital status, cognitive status, health status, self-perceived health, perceived social support, and functional status at the index wave, subthreshold depression predicted an increase of 0.1495 in IADL limitations at the subsequent wave (p=.0079) and an increase of 0.1003 mobility limitations (p=0.0073). The incremental effect of scoring 16 or greater was 0.0238 limitations (ns) for IADL and 0.0106 (ns) for mobility, suggesting that the effect of more symptomatic depression did not differ from that of subthreshold depression. Neither subthreshold depression nor the incremental effect of a score of 16+ were predictive of Katz ADL, although both estimates were in the appropriate direction. Low levels of depressive symptomatology were predictive of decline in mobility and IADL.

Learning Objectives:

• At the conclusion of the session, participants will be able to recognize the importance of subthreshold depression in older adults and the potential functional decline associated with this common condition.

Keywords: Depression, Disability

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.