Poor physical performance predicts future onset of depression in elderly people: Progetto veneto anziani longitudinal study

Background. Reduced physical performance is predictive of deleterious outcomes in older adults. Data considering objective physical performance and incident depression are sparse. Objective. The objective of this study was to investigate during a 4-year study whether objective physical performance can predict incident depression among older adults who do not have depression at the baseline. Design. This was a longitudinal study. Methods. From 3,099 older people initially enrolled in the Progetto Veneto Anziani study, 970 participants without depression at the baseline were included (mean age = 72.5 years; 54.6% women). Physical performance measures included the Short Physical Performance Battery, 4-m gait speed, Five-Times Sit-to-Stand test, leg extension and flexion, handgrip strength, and 6-minute walk test, categorized in sex-specific tertiles. Depression was classified on the basis of the Geriatric Depression Scale and a diagnosis from a geriatric psychiatrist. Area under the curve and logistic regression analyses were conducted. Results. At the baseline, participants developing depression during the follow-up (n = 207) scored significantly worse across all physical performance measures than those who did not develop depression. The area under the curve and predictive power were similar for all of the physical performance tests assessed. In the logistic regression analysis, after adjustment for 14 potential confounders, worse physical performance across all tests increased the risk of depression. Participants in the lowest tertile of the Short Physical Performance Battery were at notable odds of developing depression (odds ratio = 1.79; 95% CI = 1.18-2.71). The association between poor physical performance and depression was typically stronger in women than in men, except for 4-m gait speed. Limitations. No gold standard was used for a depression diagnosis; oxidative stress and inflammatory markers were not included; and there was a high rate of missing data at the follow-up. Conclusions. Low physical performance appeared to be an independent predictor of depression over a 4-year follow-up in a sample of elderly people. © 2017 American Physical Therapy Association.