Self-rated health predicts decline in instrumental activities of daily living among high-functioning community-dwelling older people.

Background: self-rated health (SRH) is a strong predictor of mortality, but it is unclear if SRH independently predicts a decline in instrumental activities of daily living (IADL).

Objective: to verify whether SRH is an independent predictor of IADL decline.

Design: a population-based longitudinal cohort study.

Setting: two local municipalities in Nara, Japan.

Subjects: community-dwelling older adults 65 years or older (2,638 males and 3,346 females) with independent IADL at baseline.

Methods: SRH was assessed using a single-item measure. IADL was assessed using the Tokyo Metropolitan Institute of Gerontology Index of Competence. Multiple logistic regressions were used to examine the association of SRH with IADL decline.

Results: during the 3-year follow-up, 13.2% of males and 8.2% of females developed IADL decline. After adjusting for age, family, body mass index, economic situations, chronic diseases, alcohol, smoking, depression, cognitive functioning and ADL, poorer SHR was significantly associated with IADL decline in both genders. Compared with very good SRH, the odds ratios of good, poor and very poor were 1.69 (95% confidence interval: 1.14-2.51), 2.10 (1.25-3.55) and 3.11 (1.50-6.45) for males, and 0.88 (0.54-1.42), 2.08 (1.16-3.75) and 3.42 (1.57-7.42) for females, respectively. Significant associations were not affected by chronic diseases, cognitive functioning or ADL but observed only among subjects aged 65-74 or those without depression.

Conclusions: this study confirms that SRH is an independent predictor of IADL decline among non-disabled community-dwelling older adults. Our findings suggest that SRH is an effective tool for identifying older people with future risk for IADL decline, particularly among the young-old or those without depression.