Gait Speed and Mortality Risk Among Community-Dwelling Older Adults with Heart Disease: Evidence from the RAND HRS

TL;DR

Slower walking speed in older adults with heart disease is linked to higher mortality risk, suggesting gait speed could help identify those needing interventions.

Contribution

This study identifies specific gait speed thresholds that predict mortality risk in older adults with heart disease.

Findings

A gait speed of ≤0.5 m/s is associated with a 3-fold higher mortality risk compared to faster walking speeds.

Gait speed thresholds (0.5-0.75 m/s and 0.75-1.0 m/s) show progressively lower mortality risk compared to the slowest group.

Gait speed is a valuable prognostic marker for mortality in older adults with heart disease.

Abstract

We examined the relationship of heart disease and gait speed with all-cause mortality over 11 years of follow-up among community-dwelling older adults. Participants (N = 1153) were from the RAND Health and Retirement Study Longitudinal 2020 (v2) dataset, a nationally-representative longitudinal study that began in 1992. Measures included socio-demographics, multi-morbidity status, depressive symptoms, cognitive function, and all-cause mortality. We used Cox-Proportional Hazards to estimate the hazard ratio (HR) and 95% confidence interval (CI) of all-cause mortality as a function of gait speed. We also examined the nonlinear form of gait speed to obtain the best cut-off points for predicting mortality that are more applicable in the clinical setting than its linear form. Participants were categorized into four groups based on gait speed cut-off (≤0.5 m/s, 0.5-≤0.75 m/s, 0.75-≤1.0 m/s, >1m/s). Older adults with heart disease and slower gait speed of ≤ 0.5m/sec are more at higher risk for mortality (HR = 3.02, 95% CI = 2.18-3.06), while, those with gait speed 0.5-≤0.75 m/s are at moderately elevated risk for mortality (HR = 2.25, 95% CI 1.61-3.16), and those with gait speed 0.75-≤1.0 m/s are at lower risk than the slow walking groups (HR = 1.85, 95% CI 1.38-2.47), compared to those with gait speed >1m/sec after controlling for all covariates. These findings underscore the value of gait speed as a prognostic marker and highlight the need for targeted interventions such as lower-extremity strengthening and endurance training to preserve mobility and reduce mortality risk in this vulnerable population.