Low Body Mass Index and Low Serum Albumin Are Predictive Factors for Short-Term Mortality in Elderly Japanese Requiring Home Care

Japan has a rapidly growing elderly population requiring care. This study aimed to clarify risk factors for two-year mortality in such people. Subjects included 205 community-dwelling elderly people, who were approved for care in the 2003 Yamato Study, an epidemiologic study of individuals utilizing the long-term care service system. Demographic characteristics, Barthel index (measuring activities of daily living), grip strength, thigh muscle volume, psychological evaluation, and blood values including hemoglobin, serum albumin, and serum 25-hydroxyvitamin D levels were investigated at baseline. The average age of subjects was 83.6 (S.D., 8.0) years. Of the 205 subjects, 42 died during the follow-up period. Bivariate analysis showed that older age (p = 0.0015), lower weight (p = 0.0087), lower body mass index (BMI) (p = 0.0001), lower Barthel index (p = 0.0017), lower hemoglobin (p = 0.0180), and lower serum albumin (p = 0.0001) were associated with mortality, but that sex was not (p = 0.1248). Stepwise multiple logistic regression analysis showed that BMI < 17.1 kg/m(2) (adjusted OR = 4.0, p = 0.0007), age >or= 90 years (adjusted OR = 3.3, p = 0.0033), and lower serum albumin levels (adjusted OR = 0.86, p = 0.0007) were independently associated with mortality. We conclude that low BMI and low serum albumin are strong predictors of 2-year mortality in frail elderly individuals, and that nutritional risk should appropriately be evaluated for elderly people requiring home care.