Hand Grip Strength, Gait Speed And Incident Heart Failure In Older Adults

Title: Hand Grip Strength, Gait Speed and Incident Heart Failure in Older Adults Introduction: Heart failure (HF) is predominantly a disorder of older adults. Its cardinal feature, decreased exercise tolerance, results from both central (cardiac) and peripheral (skeletal muscle) dysfunction. Skeletal muscle weakness and frailty are common aspects of aging that are associated with vascular disease and may predispose to HF onset. Although simple measures of physical function like hand grip strength and gait speed have been linked to disability and mortality, their individual associations with incident HF in elders remain unclear. The relationship of these measures with onset of HF subtypes has not been previously studied. Hypothesis: We tested the hypothesis that lower grip strength and gait speed are independently associated with higher risk of HF and its subtypes (preserved [HFpEF] and reduced [HFrEF]). Methods: A total of 7,144 participants free of prevalent HF with available muscle measures were pooled from two prospective older cohorts, the Cardiovascular Health Study (n=4584) and the Health, Aging, and Body Composition Study (Health ABC) (n=2560). Grip strength was assessed by dynamometry, and gait speed based on a short-distance walk (calibrated to ~4 m in both studies). In a secondary analysis, we evaluated thigh muscle strength, assessed by isokinetic dynamometry in Health ABC only. Incident HF and its subtypes were adjudicated with similar methods in both studies. Cox models were fitted to estimate risks of incident HF after adjustment for potential confounders (age, sex, race/ethnicity, body mass index, smoking, alcohol, systolic blood pressure, antihypertensive medication, diabetes, coronary heart disease, cerebrovascular disease, peripheral artery disease, atrial fibrillation, forced expiratory volume in 1 second, albumin, estimated glomerular filtration rate). Results: Median age was 72, 42.2% were male, and 22.9% Black. Lower gait speed was significantly associated with higher incident HF (HR per SD = 1.16 [95% CI = 1.10-1.23]) after full adjustment, but this was not observed for lower grip strength (HR per SD = 1.02 [0.95-1.10]). Gait speed showed consistent inverse associations with both HF subtypes: HFpEF: HR per SD = 1.23 [1.10-1.36]); HFrEF (HR per SD = 1.15 [1.03-1.27]). Thigh muscle strength was not significantly associated with incident HF in Health ABC (HR per SD = 1.11 [0.95-1.30]). There was no evidence of effect modification by race or by cohort. Conclusion: In two prospective cohorts of older adults of mixed race, lower gait speed, but not strength, was associated with higher risk of HF and its subtypes. Whether this readily obtainable measure of functional capacity could be used for HF risk stratification and targeting of preventive interventions will require further study.