Mortality reduction associated with β-adrenoceptor inhibition in chronic heart failure is greater in patients with diabetes

Abstract

OBJECTIVE Diabetes increasesmortality in patients with chronic heart failure (CHF) and reduced left ventricular ejection fraction. Studies have questioned the safety ofb-adrenoceptor blockers (β-blockers) in some patients with diabetes and reduced left ventricular ejection fraction. We examined whether β-blockers and ACE inhibitors (ACEIs) are associated with differential effects on mortality in CHF patients with and without diabetes. RESEARCH DESIGN AND METHODS We conducted a prospective cohort study of 1,797 patients with CHF recruited between 2006 and 2014,withmean follow-up of 4 years.β-Blocker dose was expressed as the equivalent dose of bisoprolol (mg/day) and ACEI dose as the equivalent dose of ramipril (mg/day). Cox regression analysis was used to examine the interaction between diabetes and drug dose on all-cause mortality. RESULTS Patients with diabetes were prescribed larger doses of β-blockers and ACEIs than were patients without diabetes. Increasing β-blocker dose was associated with lower mortality in patients with diabetes (8.9% per mg/day; 95% CI 5-12.6) and without diabetes (3.5% per mg/day; 95% CI 0.7-6.3), although the effect was larger in people with diabetes (interaction P = 0.027). Increasing ACEI dose was associated with lowermortality in patientswith diabetes (5.9%per mg/day; 95%CI 2.5-9.2) and without diabetes (5.1% per mg/day; 95% CI 2.6-7.6), with similar effect size in these groups (interaction P = 0.76). CONCLUSIONS Increasing β-blocker dose is associated with a greater prognostic advantage in CHF patients with diabetes than in CHF patients without diabetes.