Examining the role of different weakness categories for mobility and future falls in older Americans

Background Recently developed absolute and body size normalized handgrip strength (HGS) cut-points could be used individually and collectively to predict mobility problems and falls. Aims We examined the associations of (1) each absolute and normalized weakness cut-point, (2) collective weakness categories, and (3) changes in weakness status on future falls in older Americans. Methods The analytic sample included 11,675 participants from the 2006–2018 waves of the Health and Retirement Study. Falls were self-reported. Men were classified as weak if their HGS was < 35.5-kg (absolute), < 0.45 kg/kg (body mass normalized), or < 1.05 kg/kg/m 2 (body mass index normalized). While, women were considered weak if their HGS was < 20.0-kg, < 0.337 kg/kg, or < 0.79 kg/kg/m 2 . Collective weakness categorized those below 1, 2, or all 3 cut-points. The collective weakness categories were also used to observe changes in weakness status over time. Results Older Americans below each absolute and normalized cut-point had greater odds for future falls: 1.23 (95% confidence interval (CI): 1.15–1.32) for absolute weakness, 1.20 (CI 1.11–1.29) for body mass index normalized weakness, and 1.26 (CI 1.17–1.34) for body mass normalized weakness. Persons below 1, 2, or all 3 weakness cut-points had 1.17 (CI 1.07–1.27), 1.29 (CI 1.18–1.40), and 1.36 (CI 1.24–1.48) greater odds for future falls, respectively. Those in some changing weakness categories had greater odds for future falls: 1.26 (CI 1.08–1.48) for persistent and 1.31 (CI 1.11–1.55) for progressive. Discussion Collectively using these weakness cut-points may improve their predictive value. Conclusion We recommend HGS be evaluated in mobility and fall risk assessments.