RESEARCH ABSTRACT QUESTION #1
Aldosterone blockade reduces mortality and morbidity among patients with severe heart failure. We conducted a double blind, placebo-controlled study evaluating the effect of eplerenone, a selective aldosterone blocker, on morbidity and mortality among patients with acute myocardial infarction complicated by left ventricular dysfunction and heart failure.
Patients were randomly assigned to eplerenone (25 mg per day initially, titrated to a maximum of 50 mg per day; 3319 patients) or placebo (3313 patients) in addition to optimal medical therapy. The study continued until 1012 deaths occurred. The primary end points were death from any cause and death from cardiovascular causes or hospitalization for heart failure, acute myocardial infarction, stroke, or ventricular arrhythmia.
During a mean follow-up of 16 months, there were 478 deaths in the eplerenone group and 554 deaths in the placebo group (relative risk, 0.85; 95 percent confidence interval, 0.75 to 0.96; P=0.008). Of these deaths, 407 in the eplerenone group and 483 in the placebo group were attributed to cardiovascular causes (relative risk, 0.83; 95 percent confidence interval, 0.72 to 0.94; P=0.005). The rate of the other primary end point, death from cardiovascular causes or hospitalization for cardiovascular events, was reduced by eplerenone (relative risk, 0.87; 95 percent confidence interval, 0.79 to 0.95; P=0.002), as was the secondary end point of death from any cause or any hospitalization (relative risk, 0.92; 95 percent confidence interval, 0.86 to 0.98; P=0.02). There was also a reduction in the rate of sudden death from cardiac causes (relative risk, 0.79; 95 percent confidence interval, 0.64 to 0.97; P=0.03). The rate of serious hyperkalemia was 5.5 percent in the eplerenone group and 3.9 percent in the placebo group (P=0.002), whereas the rate of hypokalemia was 8.4 percent in the eplerenone group and 13.1 percent in the placebo group (P<0.001).
- Which of the following statements represents the most accurate interpretation of the results from the aforementioned clinical trial?
- There was no significant difference in the incidence of hyperkalemia between trial arms.
- There was no significant difference in the rate of sudden cardiac death between trial arms.
- Epleranone, when added to optimal medical therapy, decreases all cause mortality in patients with left ventricular dysfunction following myocardial infarction.
- The rate of hypokalemia was not significantly different between trial arms.
- The most common causes of death seen in enrolled patients over the course of this trial were non-cardiac in nature.
Filed under: USMLE STEP III QUESTION BANK, USMLE Test Prep | Tagged: Archer Bio-statistics, Archer USMLE RESEARCH ABSTRACT QUESTIONS, Research Abstract Questions, Research Abstract Questions Step 3, USMLE Step 3 Bio-statistics | 1 Comment »