Abstract 1357: Renal Dysfunction, Fitness and the Risk of Death in Women
Background: Chronic kidney disease is associated with increased risk of cardiovascular (CV) events and death, but its association with cardiorespiratory fitness is unknown in women.
Methods: To assess the association between kidney function and fitness on all-cause mortality, we estimated glomerular filtration rate (eGFR) in a prospective cohort of 5716 asymptomatic women. Serum creatinine, spot urine protein and maximal stress tests were performed at baseline.
Results: Mean follow-up was 15.9±2.2 years with 589 deaths identified. Mean age at baseline was 52.5 ±10.8 years, 86% Caucasian. Mean serum creatinine (Cr) was 1.11±0.14 mg/dL, mean eGFR was 53.7±8.3 ml/minute/1.73m2. Cr >1.4 was associated with a hazards ratio (HR) of all-cause mortality of 1.59 (P=0.025). After adjustment for traditional CV risk factors and fitness, the HR for death decreased by 3% (P<0.001) for every ml/minute/1.73m2 increase in eGFR. Compared to women with an eGFR <45 ml/minute/1.73m2, the risk of death reduced by 36% and 47%, for eGFR 45–59.9 ml/minute/1.73m2 and eGFR ≥60 ml/minute/1.73m2, respectively (P<0.001). At every level of eGFR, fitness at baseline remained an independent predictor of mortality, with the lowest level of fitness (<5 METs) being at the highest risk of mortality, regardless of eGFR.
Conclusions: Fitness remains an independent predictor of mortality, regardless of eGFR. eGFR was a stronger predictor of all-cause mortality compared to Cr or proteinuria. These findings have important implications for clinical practice and health care policy, in that the level of fitness predicts risk in the presence of chronic kidney disease, which is a well-defined risk factor.