title: Body mass index and the risk of incident functional disability in elderly Japanese: The OHSAKI Cohort 2006 Study.
abstract: The relationship between the body mass index (BMI) and the incidence of cause-specific disability remains unclear.We conducted a prospective cohort study of 12,376 Japanese individuals aged ≥65 years who were followed up for 5.7 years. Information on BMI and other lifestyle factors was collected via a questionnaire in 2006. Functional disability data were retrieved from the public Long-term Care Insurance database. BMI was divided into 6 groups (<21, 21-<23, 23-<25, 25-<27[reference], 27-<29 and ≥29). Hazard ratios and 95% confidence intervals for cause-specific disability were estimated using Cox proportional hazards regression models.A U-shaped relationship between BMI and functional disability was observed, with a nadir at 26. The nadir BMI values with the lowest disability risk were 28 for dementia, 25 for stroke, and 23 for joint disease. A low BMI (<23) was a risk factor for disability due to dementia, the HR values (95% CI) being 2.48 (1.70-3.63) for BMI <21 and 2.25 (1.54-3.27) for BMI 21 to <23; a high BMI (≥29) was a risk factor for disability due to joint disease, the HR value (95% CI) being 2.17 (1.40-3.35). There was no significant relationship between BMI and disability due to stroke.The BMI nadirs for cause-specific disability differed: a low BMI (<23) was a risk factor for disability due to dementia, and a high BMI (≥29) was a risk factor for disability due to joint disease. Because BMI values of 23 to <29 did not pose a significantly higher risk for each cause of disability, this range should be regarded as the optimal one for the elderly population.
authors: Division of Epidemiology, Tohoku University School of Public Health, Graduate School of Medicine, Sendai, Miyagi, Japan.
authors: Shu
authors: S
authors: Zhang
authors: Yasutake
authors: Y
authors: Tomata
authors: Kemmyo
authors: K
authors: Sugiyama
authors: Yu
authors: Y
authors: Kaiho
authors: Kenji
authors: K
authors: Honkura
authors: Takashi
authors: T
authors: Watanabe
authors: Fumiya
authors: F
authors: Tanji
authors: Yumi
authors: Y
authors: Sugawara
authors: Ichiro
authors: I
authors: Tsuji
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015331:Cohort Studies; D003704:Dementia / Q000453:epidemiology; D006233:Persons with Disabilities; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007592:Joint Diseases / Q000453:epidemiology; D008297:Male; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology