Abstract 18836: Differences in Cardiopulmonary Exercise Test Data and Prognosis in Black and White Men with Heart Failure: the Henry Ford HospITal CardioPulmonary EXercise Testing (FIT-CPX) Project

Abstract

Introduction: Numerous metrics from the cardiopulmonary exercise test (CPX) are associated with outcomes among patients with heart failure with reduced ejection fraction (HFrEF). Among patients with HFrEF, mortality rates differ by race; however, the influence of race on the association between common measures obtained during CPX and mortality has not been fully described. Purpose: Retrospective analysis to describe the relationship between key CPX measures and the composite endpoint of mortality, left ventricular assist device (LVAD), or cardiac transplant (CT) in white and black men with HFrEF. Methods: Self-identified white and black male patients (n= 761; age= 55 ± 12 y; BMI= 30.6±6.6) with a CPX between 1997 and 2010 and confirmed HFrEF (ejection fraction [EF] ≤ 40%) were identified. Endpoint data was obtained through 2011. The association with the composite endpoint was evaluated separately for 7 key CPX measures with adjustment for age, hypertension, beta-blocker therapy, EF, and ischemic etiology using Cox regression stratified by race. Results: During a median follow-up of 3.5 y there were 195 (54%) and 193 (48%) events for white and black patients, respectively. All CPX variables were associated (p<0.05) with the composite endpoint in both white and black patients (Table). The greatest Wald statistic among white patients was % predicted peak oxygen uptake (ppVO 2 ) at 76.2, and among black patients it was ventilatory efficiency (V E -VCO 2 slope) at 90.8. Conclusion: Among white and black male patients, % predicted peak VO 2 and V E -VCO 2 slope, respectively, were most strongly associated with the combined end point of mortality, LVAD or CT. These data suggest that risk stratification using CPX variables may differ by race. Further research is needed to determine if race-specific methods of CPX-based risk stratification are needed.