Physical disability and depressive symptomatology in an elderly population: a complex relationship. The Italian Longitudinal Study on Aging (ILSA)

Abstract

Objectives: Depressive symptoms (DS) are very frequent in elderly individuals and are associated with negative outcomes. This study was undertaken to evaluate whether DS predict physical disability in this population.

Methods: A prospective,community-based cohort study, this work included 5,632 individuals aged 65-84 years, who were recruited from the demographic registries of eight Italian municipalities in 1992. The complete data of 3,256 subjects were collected and analyzed. DS were assessed using the Geriatric Depression Scale with a score > or = 10/30 indicating DS. All traditional risk factors for disability established by questionnaires and physical examinations were assessed at baseline. The outcomes were self-reported disability on the activities of daily living (ADL) test and the performance-based physical function assessment (Physical Performance Tests, PPT). The contribution of the predictive variables to the outcomes evaluated after a mean follow-up of 3.5 +/- 0.4 years was assessed using hierarchical logistic nested models.

Results: Baseline DS was associated with higher rates of ADL disability (odds ratio [OR] 1.73, 95%confidence interval [CI] 1.12-2.66) and PPT disability (OR 1.83, 95% CI 1.17-2.85)in men and with ADL disability (OR 1.81, 95% CI 1.28 -2.55) in women. The independent predictors of PPT disability in women were arthritis (OR 2.13, 95% CI 1.28 -3.53) and age (OR 1.09; 95% CI 1.03-1.15).

Conclusions: This study provides evidence that older persons who report DS are at higher risk of subsequent physical decline. In women, arthritis is a more powerful predictor of preclinical disability, as measured by PPT.