Two Methods of Handgrip Strength Assessment in Sarcopenia Evaluation: Associations with in-Hospital Mortality in Older Adults.

Background: Handgrip strength (HGS) is a key diagnostic tool for sarcopenia, yet the comparative prognostic value of the hydraulic dynamometer and pneumatic vigorimeter in hospitalized older adults remains unclear. This study is the first to examine the vigorimeter as a predictor of in-hospital mortality in this setting.

Methods: This prospective cohort study included 376 hospitalized older adults (mean age: 82.7 years) across acute, rehabilitation, and long-term care wards. HGS was assessed using both the dynamometer and vigorimeter, applying two sets of cut-offs per instrument. Sarcopenia was confirmed using bioelectrical impedance analysis to calculate the fat-free mass index (FFMI), with four diagnostic criteria combining HGS and FFMI thresholds. Associations between HGS, sarcopenia, and mortality were evaluated using logistic regression and Cox proportional hazards models, with Kaplan-Meier curves illustrating survival differences.

Results: Higher HGS measured by the vigorimeter was independently associated with reduced in-hospital mortality (OR 0.96, 95% CI 0.93-0.98, p = 0.001), whereas no significant association was found for dynamometer-measured HGS. Confirmed sarcopenia was significantly associated with mortality for two diagnostic criteria (criterion 2: vigorimeter with DO-HEALTH1 cut-offs: OR 1.77, 95% CI 1.01-3.10, p = 0.047; criterion 4: vigorimeter with DO-HEALTH2 cut-offs: OR 1.76, 95% CI 1.01-3.07, p = 0.048), although no significant association was observed with time-to-mortality. Kaplan-Meier curves demonstrated significant survival differences only for vigorimeter-based HGS cut-offs (p = 0.04). Male sex and falls during hospitalization were associated with increased mortality, while admission to rehabilitation or long-term care wards was associated with reduced mortality.

Conclusion: Vigorimeter-based HGS, especially using DO-HEALTH1 cut-offs, demonstrated superior prognostic value for in-hospital mortality compared to the dynamometer. These findings support the clinical utility of the vigorimeter for risk stratification and care planning in hospitalized older adults, particularly in settings where subtle neuromuscular deficits may influence outcomes.