Estimated Glomerular Filtration Rate and 6-Minute Walk Distance in African Americans with Mild to Moderate Heart Failure

Abstract

Background/Aims: The 6-minute walk test is a measure of functional capacity in patients with heart failure (HF) or chronic kidney disease (CKD). The association between estimated glomerular filtration rate (eGFR) and 6-minute walk distance (6MWD) has not been investigated in African-Americans (AA), despite them having a higher incidence of CKD and chronic HF. Thus, our aim was to determine if eGFR was an independent predictor of 6MWD in AA >50 years of age with HF. Methods: In this cross-sectional study, we examined the relationship between eGFR and 6MWD in 45 AA patients with HF from an urban outpatient HF clinic, using logistic regression with bootstrapping. Results: The sample consisted of 53% females; mean age = 64.8 ± 9 years, mean eGFR = 61.6 ± 20 mL/min/1.73 m², and mean 6MWD = 222 ± 78 m. A decrease in eGFR by 10 mL/min/1.73 m² was associated with 46% higher odds (p = 0.02) of a 6MWD ≤200 m in an unadjusted model and 39-41% higher odds (p = 0.03) of a 6MWD ≤200 m in adjusted models. Conclusion: A decrease in eGFR significantly predicted a shorter 6MWD in AA patients with HF. Therefore, a reduction in eGFR may be used as an early marker to identify and manage declining functional capacity in these patients.