Anthropometric measurements of mid-upper arm as a mortality predictor for community-dwelling Japanese elderly: The Nagoya Longitudinal Study of Frail Elderly (NLS-FE)

Background & aims: It remains controversial whether mid-arm anthropometric measurements (MAAMs) are reflected with physical impairment or useful predictors of mortality in the frail elderly. We examined the following hypotheses: (1) MAAMs in frail community-dwelling elderly are lower than those of independent elderly, (2) the lower MAAMs are associated with physical function impairment, and (3) are independent predictors of 2-year mortality. Methods: This study was composed of cross-sectional and prospective cohort analyses of 957 community-dwelling elderly. Data included the clients' demographic characteristics, comorbidity, activities of daily living (ADL), and MAAMs at baseline. The mean scores of MAAMs of participants were compared with Japanese Anthropometric Reference Data. Survival analysis of 2-year mortality was conducted using multivariate Cox proportional hazards models. Results: Significantly lower arm muscle area (AMA) and higher triceps skinfold (TSF) levels were observed in most of the age groups of the study participants than those of the standard Japanese population. ADL function was correlated with AMA but not with TSF, both of which were independent risk factors for 2-year mortality in the participants (highest tertile versus lowest, AMA, HR:2.03, 95%CI:1.36-3.02; TSF, HR:1.89, 95%CI:1.30-2.75). Conclusions: AMA and TSF were independent risk factors for 2-year mortality in the community-dwelling frail elderly.