Prediction of functional disability by depressive state among community-dwelling elderly in Japan: a prospective cohort study.

AIM: We carried out a prospective cohort study to evaluate the risk factors of functional disability by depressive state.

METHODS

A total of 783 men and women, aged 70 years and over, participated in this study. We followed the participants in terms of the onset of functional disability by using a public long-term care insurance database. The Geriatric Depression Scale (GDS) was used to measure depressive state. Age, sex, history of chronic disease, living alone, fall experience, cognitive impairment, instrumental activities of daily living (IADL), the Motor Fitness Scale (MFS), frequency of going out and social support at baseline were used as the main covariates. The Cox regression analysis was used to examine the difference in functional disability stratified according to depressive state.

RESULTS

The incidence of functional disability was 38 persons in the non-depression group and 42 persons in the depression group (RR 2.34; 95% CI 1.46-3.79). The results of the depression group showed a significant difference in cognitive impairment (HR 3.51; 95% CI 1.39-8.85), MFS (HR 5.60; 95% CI 1.32-23.81) and IADL (HR 3.37; 95% CI 1.65-6.85). The results of the non-depression group showed a significant difference in MFS (HR 2.97; 95% CI 1.47-6.96), and frequency of going out (HR 3.21; 95% CI 1.47-6.96).

CONCLUSIONS

In conclusion, risk factors for functional disability were found to differ on the basis of whether or not community-dwelling elderly individuals experience depressive state. The type of support offered must be based on whether or not depressive state is present.