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.