Relationship between stage of kidney disease and incident heart failure in older adults.

BACKGROUND The relationship between stage of chronic kidney disease (CKD) and incident heart failure (HF) remains unclear. METHODS Of the 5,795 community-dwelling adults ≥65 years in the Cardiovascular Health Study, 5,450 were free of prevalent HF and had baseline estimated glomerular filtration rate (eGFR: ml/min/1.73 m(2)) data. Of these, 898 (16%) had CKD 3A (eGFR 45-59 ml/min/1.73 m(2)) and 242 (4%) had CKD stage ≥3B (eGFR <45 ml/min/1.73 m(2)). Data on baseline proteinuria were not available and 4,310 (79%) individuals with eGFR ≥60 ml/min/1.73 m(2) were considered to have no CKD. Propensity scores estimated separately for CKD 3A and ≥3B were used to assemble two cohorts of 1,714 (857 pairs with CKD 3A and no CKD) and 557 participants (148 CKD ≥3B and 409 no CKD), respectively, balanced on 50 baseline characteristics. RESULTS During 13 years of follow-up, centrally-adjudicated incident HF occurred in 19, 24 and 38% of pre-match participants without CKD (reference), with CKD 3A [unadjusted hazard ratio (HR) 1.40; 95% confidence interval (CI) 1.20-1.63; p < 0.001] and with CKD ≥3B (HR 3.37; 95% CI 2.71-4.18; p < 0.001), respectively. In contrast, among matched participants, incident HF occurred in 23 and 23% of those with CKD 3A and no CKD, respectively (HR 1.03; 95% CI 0.85-1.26; p = 0.746), and 36 and 28% of those with CKD ≥3B and no CKD, respectively (HR 1.44; 95% CI 1.04-2.00; p = 0.027). CONCLUSIONS Among community-dwelling older adults, CKD is a marker of incident HF regardless of stage; however, CKD ≥3B, not CKD 3A, has a modest independent association with incident HF.