Managing the patient with diabetes mellitus and heart failure: issues and considerations

Heart failure affects nearly 5 million Americans and is associated with high morbidity and mortality rates. It is now recognized that activation of multiple neurohormonal systems is intrinsic in the pathophysiology of heart failure. Patients with diabetes mellitus are at high risk for heart failure, and some of the complications of diabetes (e.g., insulin resistance) contribute to the development and progression of heart failure, partly because of their effects on neurohormonal systems. Pharmacologic intervention directed toward these systems (i.e., angiotensin-converting enzyme [ACE] inhibition, use of aldosterone antagonists, and beta-adrenergic blockade) has been shown to decrease the morbidity and mortality associated with heart failure. Despite this knowledge, ACE inhibitors, aldosterone antagonists, and beta-blockers are grossly underused, and deaths and hospitalizations due to heart failure have steadily increased. Guidelines for the management of heart failure recommend the use of ACE inhibitors and beta-blockers in patients with mild, moderate, or severe disease. Aldosterone antagonists are recommended in severe heart failure, and recent data also support their use in mild to moderate heart failure. Concerns about the increased incidence of hypoglycemia, worsening dyslipidemia, and decreased insulin sensitivity with beta-blocker use may be preventing physicians from prescribing these agents for patients with diabetes with heart failure. Although evidence from earlier clinical trials justifies some of these concerns, newer vasodilating beta-blockers (e.g., carvedilol) have been shown to have a neutral or positive effect on dyslipidemia and insulin resistance. beta-Blockade in conjunction with ACE inhibition should be standard therapy for all patients with diabetes who have heart failure. Furthermore, early in-hospital initiation of neurohormonal intervention can provide earlier benefit to these patients.