Appendicular Lean Mass, Grip Strength, and the Development of Hospital-Associated Activities of Daily Living Disability Among Older Adults in the Health ABC Study.

BACKGROUND: Half of all physical disability, including activity of daily living (ADL) disability, among older adults occurs in the setting of hospitalization. This study examines whether appendicular lean mass (ALM) and grip strength, which are commonly included in various definitions of sarcopenia, are associated with the development of hospital-associated ADL disability in older adults in the Health ABC Study.

METHODS: Individuals hospitalized during the first 5 years of follow-up (n = 1 724) were analyzed. ALM to body mass index (BMI) ratio (ALMBMI), by dual-energy x-ray absorptiometry (DXA), and grip strength, by hand-held dynamometery, were assessed annually. Development of new ADL disability was assessed at the time of the next annual assessment after hospitalization. Separate regression analyses modeled the association of prehospitalization ALMBMI or grip strength with death before the next scheduled annual assessment. Next, among those who survived to the next annual assessment, separate regression analyses modeled the association of ALMBMI or grip strength with development of ADL disability.

RESULTS: Each standard deviation decrement in prehospitalization grip strength was associated with an adjusted 1.80 odds of new ADL disability at follow-up (95% CI: 1.18, 2.74). Low, compared with not low, grip strength (per FNIH definition) was associated with an adjusted 2.36 odds of ADL disability at follow-up (95% CI: 1.12, 4.97). ALM measures were not associated with the development of hospital-associated ADL disability. ALM and grip strength measures were not associated with death.

CONCLUSIONS: Prehospitalization lower grip strength may be an important risk factor for ADL disability among older adult survivors of hospitalization.