Renal insufficiency and heart failure: prognostic and therapeutic implications from a prospective cohort study.

Abstract

The prevalence, prognostic import, and impact of renal insufficiency on the benefits of ACE inhibitors and beta-blockers in community-dwelling patients with heart failure are uncertain. We analyzed data from a prospective cohort of 754 patients with heart failure who had ejection fraction, serum creatinine, and weight measured at baseline. Median age was 69 years, and 43% had an ejection fraction > or =35%. By the Cockcroft-Gault equation, 118 patients (16%) had creatinine clearances < or =30 mL/min and 301 (40%) had creatinine clearances between 30 and 59 mL/min. During follow-up (median 926 days), 385 patients (37%) died. Even after adjustment for all other prognostic factors, survival was significantly associated with renal function (P=0.002) in patients with either systolic or diastolic dysfunction; patients exhibited a 1% increase in mortality for each 1-mL/min decrease in creatinine clearance. The associations with 1-year mortality reductions were similar for ACE inhibitors (OR 0.46 [95% CI 0.26 to 0.82] versus OR 0.28 [95% CI 0.11 to 0.70]) and beta-blockers (OR 0.40 [95% CI 0.23 to 0.70] versus OR 0.41 [95% CI 0.19 to 0.85]) in patients with creatinine clearances <60 mL/min versus > or =60 mL/min, although these drugs were used less frequently in patients with renal insufficiency. Renal insufficiency is more prevalent in patients with heart failure than previously reported and is an independent prognostic factor in diastolic and systolic dysfunction. ACE inhibitors and beta-blockers were associated with similar reductions in mortality in patients with and without renal insufficiency.