Prospective Study of Trajectories of Physical Performance and Mortality Among Community-Dwelling Older Japanese

Physical performance measures (PPMs) are good predictors of adverse health outcomes in later life. This prospective study used repeated measures analysis to examine sex-specific age trends in PPMs, identify potential PPM trajectory patterns, and determine whether PPM trajectory patterns were associated with all-cause mortality among older Japanese. Among 1,524 adults aged 65 years or older who participated in a baseline survey, 1,048 adults (mean [SD] age, 71.6 [5.4] years; women, 57.0%) were followed up at least once. The total number of observations was 4,747, and the average number of follow-up assessments was 4.5 during the period from 2002 through 2011. The PPMs studied were handgrip strength, usual gait speed, and one-leg standing time. We checked local registries to identify deaths from any cause; 89 (8.5%) participants died during follow-up. All PPMs significantly decreased with advancing age, and handgrip strength and usual gait speed showed sex-specific age trends. We identified three distinct trajectory patterns (high, middle, and low trajectory groups) for each PPM in adults aged 65-90 years, and the trajectories for handgrip strength and usual gait speed showed parallel declines in men and women, respectively. After adjusting for important confounders, the trajectory groups for handgrip strength and one-leg standing time were independent predictors of all-cause mortality. Regardless of baseline level, the PPMs tended to show similar age-related changes in later life. However, individuals in low PPM trajectory groups had a higher mortality risk, which highlights the importance of interventions that maintain or improve physical performance, even among older adults with low physical performance.