Prediction of renal impairment in elderly patients with congestive heart failure treated with captopril

Management of Cardiac Failure—Do Practitioners Follow Guidelines?

Objective:

To assess the use of β-blockers, spironolactone, and the dose of angiotensin-converting enzyme (ACE) inhibitors in patients with congestive cardiac failure.

Methods:

The medical records of patients discharged with a diagnosis of congestive cardiac failure between January 1, 2001, and June 30, 2001, from the internal medicine and cardiology services at Capital and Coast District Health Board, Wellington, New Zealand, were identified and analyzed for cardiac drugs on admission and discharge. These records were also reviewed for New York Heart Association status and left-ventricular ejection fraction.

Results:

Two hundred ninety-two patients (146 from each service) were identified as having congestive cardiac failure; 84 were excluded due to death, admission being procedure related, notes being unavailable, or transfers from other services. The patients' mean age was 73 years. Four of 74 eligible patients were started on β-blockers, while 11 of 30 eligible patients were started on spironolactone. Sixteen patients were prescribed spironolactone inappropriately, and 27 were prescribed target recommended doses of ACE inhibitors.

Conclusions:

This study has shown that guidelines for the treatment of cardiac failure are difficult to follow in clinical practice. Adequate studies in older individuals with congestive cardiac failure are indicated.

The kidney in congestive heart failure: renal adverse event rate of treatment

In this paper we review the effect of medical treatment on renal function in patients with congestive heart failure. We have examined data from the large-scale heart failure studies with angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, calcium channel blockers, beta-receptor blockers, an aldosterone antagonist, and a vasopeptidase inhibitor. Renal outcome was reported in almost all of the studies with angiotensin-converting enzyme inhibitors. Despite concern about renal adverse events with drugs in this class, they seem to be safe in patients with congestive heart failure. In contrast, we did not find any report about renal function in patients treated with beta-receptor blockers for congestive heart failure.

Predictors of decreased renal function in patients with heart failure during angiotensin-converting enzyme inhibitor therapy: results from the studies of left ventricular dysfunction (SOLVD)

BACKGROUND

Although angiotensin-converting enzyme inhibitor therapy reduces mortality rates in patients with congestive heart failure (CHF), it may also cause decreased renal function. Little information is available to predict which patients are at highest risk for this complication.

OBJECTIVE

To quantify specific clinical predictors of reduction in renal function in patients with CHF who are prescribed angiotensin-converting enzyme inhibitor therapy.

METHOD

We analyzed data from the Studies of Left Ventricular Dysfunction (SOLVD), a randomized, double-blind, placebo-controlled trial of enalapril for the treatment of CHF. There were 3379 patients randomly assigned to enalapril with a median follow-up of 974 days and 3379 patients randomly assigned to placebo with a mean follow-up of 967 days. Decreased renal function was defined as a rise in serum creatinine >/=0.5 mg/dL (44 micromol/L) from baseline. We used time-to-event analysis to identify potential predictors of decrease in renal function including age, baseline ejection fraction, baseline creatinine, low systolic blood pressure (<100 mm Hg), history of hypertension, diabetes, and use of antiplatelet, diuretic, and beta-blocker therapy.

RESULTS

Patients randomly assigned to enalapril had a 33% greater likelihood of decreased renal function than controls (P =.003). By multivariate analysis, in both the placebo and enalapril groups older age, diuretic therapy, and diabetes were associated with decreased renal function, whereas beta-blocker therapy and higher ejection fraction were renoprotective. Older age was associated with a greater risk of developing decreased renal function in both groups, but significantly more so in the enalapril group (enalapril: risk ratio [RR] 1.42 per 10 years, 95% confidence interval [CI] 1.32-1.52 with enalapril; placebo: RR 1.18, 95% CI 1.12-1.25). Diuretic therapy was likewise associated with a greater risk of decreased renal function in the enalapril group (RR 1.89, 95% CI 1.70-2.08) than in the placebo group (RR 1.35, 95% CI 1.09-1.66). Conversely, enalapril had a relative renoprotective effect (RR 1.33, 95% CI 1.13-1.53) compared with placebo (RR 1.96, 95% CI 1.57-2.44) in patients with diabetes. A lower risk of renal impairment was seen in both groups with beta-blocker therapy (RR 0.70, 95% CI 0.57-0.85) and higher baseline ejection fraction (RR 0.93 per 5% increment, 95% CI 0.91-0. 96).

CONCLUSIONS

Enalapril use caused a 33% increase in the risk of decreased renal function in patients with CHF. Diuretic use and advanced age increased this risk. Diabetes was associated with an increased risk of renal impairment in all patients with CHF, but this risk was reduced in the enalapril group compared with the placebo group. beta-Blocker therapy and higher ejection fraction were renoprotective in all patients regardless of therapy.