Handgrip strength asymmetry is associated with slow gait speed and poorer standing balance in older Americans

Introduction Handgrip strength (HGS) asymmetry may help identify the functional asymmetries that contribute to mobility limitations. We sought to determine the associations of HGS asymmetry on gait speed and standing balance in older Americans. Materials and Methods The analytic sample included 8,396 adults aged ≥65-years for the last wave in which they participated in the 2006-2016 Health and Retirement Study. Participants were categorized into asymmetry groups based on the degree of HGS asymmetry. Persons with gait speed <0.8 meters/second were slow. Balance scores ranged from 0-4 with lower scores representing poorer standing balance. Results Older Americans with 20.1%-30.0% asymmetry had 1.22 (95% confidence interval (CI): 1.05-1.42) greater odds for slow gait speed, while those with >30.0% asymmetry had 1.23 (CI: 1.05-1.44) greater odds. Persons with 10.1%-20.0%, 20.1%-30.0%, and >30% asymmetry had 1.09 (CI: 1.07-1.22), 1.23 (CI: 1.07-1.42) and 1.40 (CI: 1.22-1.61) greater odds for poorer static balance, respectively. Those in each individual asymmetry group had greater odds for slow gait speed: 1.14 (CI: 1.03-1.26) for >10.0%, 1.19 (CI: 1.07-1.33) for >20.0%, and 1.16 (CI: 1.01-1.35) for >30.0%. Similar results were observed for poorer balance: 1.20 (CI: 1.09-1.32) for >10.0%, 1.27 (CI: 1.15-1.41) for >20.0%, and 1.31 (CI: 1.16-1.49) for >30.0%. Every 10% asymmetry increase was associated with 1.62 (CI: 1.32-1.99) greater odds for poorer balance. Conclusions The bimanual aspects of HGS asymmetry may reflect the bilateral movements required for mobility, and the relationship between upper and lower extremity strength and function may elucidate our findings.