Background: Evaluating handgrip strength (HGS) asymmetry may help to improve the prognostic value of HGS. This study sought to determine the associations of HGS asymmetry and weakness on future activities of daily living (ADL) disability in a national sample of aging Americans. Methods: The analytic sample included 18,468 Americans aged ≥50 years from the 2006–2016 waves of the Health and Retirement Study. A handgrip dynamometer measured HGS. Those with HGS >10% stronger on either hand were considered as having any HGS asymmetry. Individuals with HGS >10% stronger on their dominant hand were considered as having dominant HGS asymmetry, while those with HGS >10% stronger on their nondominant hand were classified as having nondominant HGS asymmetry. Men with HGS <26 kg and women with HGS <16 kg were considered weak. ADLs were self-reported. Generalized estimating equations were used for analyses. Results: Relative to those with symmetric HGS and no weakness, each HGS asymmetry and weakness group had increased odds for future ADL disability: 1.11 (95% confidence interval [CI]: 1.02–1.20) for any HGS asymmetry alone, 1.42 (CI: 1.16–1.74) for weakness alone, and 1.81 (CI: 1.52–2.16) for both any HGS asymmetry and weakness. Most weakness and HGS asymmetry dominance groups had increased odds for future ADL disability: 1.30 (CI: 1.13–1.50) for nondominant HGS asymmetry alone, 1.42 (CI: 1.16–1.74) for weakness alone, 1.72 (CI: 1.29–2.29) for both weakness and nondominant HGS asymmetry, and 1.86 (CI: 1.52–2.28) for both weakness and dominant HGS asymmetry. Conclusions: HGS asymmetry and weakness together may increase the predictive utility of handgrip dynamometers.

Purpose: To determine the time-varying associations between 1) decreased handgrip strength and disabilities in each activity of daily living (ADL) function, and 2) disaggregated ADL limitations and time to mortality in older adults. Methods: A United States nationally representative sample of 17,747 older adults from the Health and Retirement Study were followed up for 8 yr. Maximal handgrip strength was measured with a hand-held dynamometer. Ability to perform ADL was self-reported. Date of death was identified by the National Death Index and exit interviews. Separate covariate-adjusted hierarchical logit models were used to examine the time-varying associations between decreased handgrip strength and each ADL outcome. Distinct covariate-adjusted Cox models were used to analyze the time-varying associations between disaggregated ADL limitations and time to mortality. Results: Every 5-kg decrease in handgrip strength was associated with increased odds for the following ADL limitations: 20% for eating, 14% for walking, 14% for bathing, 9% for dressing, 8% for transferring, and 6% for toileting. The presence of a bathing, walking, toileting, eating, and dressing ADL disability was associated with a 47%, 43%, 32%, 30%, and 19% higher hazard for mortality, respectively. A transferring ADL disability was not significantly associated with mortality. Conclusions: Decreased handgrip strength was associated with increased odds for each ADL limitation, and in turn, most individual ADL impairments were associated with a higher hazard for mortality in older adults. These findings provide insights into the disabling process by identifying which ADL limitations are most impacted by decreased handgrip strength and the subsequent time to mortality for each ADL disability.