Addition of Losartan to Angiotensin-Converting Enzyme Inhibitors Improves Insulin Resistance in Patients With Chronic Heart Failure Treated Without β-Blockers

Background: Angiotensin II and insulin resistance (IR) have clinical implications in the pathophysiology of chronic heart failure (CHF). However, it is still unclear whether the combination of an angiotensin-receptor blocker and angiotensin-converting enzyme inhibitor (ACEI) improves IR in CHF patients who do not receive beta-blockers. Thus, the aim of the present study was to evaluate the effects of losartan on glucose metabolism and inflammatory cytokines in CHF patients treated with ACEI but not beta-blockers. Methods and Results: The effect of losartan treatment for 16 weeks on IR was analyzed in 16 CHF patients in a randomized crossover trial. Insulin level and homeostasis model IR index (HOMA-IR) decreased significantly (P<0.05), but fasting plasma glucose did not change significantly. Serum tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1 levels were significantly decreased with losartan (P<0.05). Furthermore, the changes in IL-6 and MCP-1 levels were significantly correlated with the reduction in HOMA-IR (P<0.05), but the change in TNF-alpha levels was not significantly correlated. Conclusions: The addition of losartan to ACEI therapy improved IR and decreased inflammatory cytokines in CHF patients who did not receive beta-blockers. (Circ J 2010; 74: 2346-2352)