Betablocker treatment in diabetes mellitus.

OBJECTIVES: Betablockers have been convincingly shown to reduce total and cardiovascular morbidity and mortality of hypertensive diabetic patients. In diabetic patients, after myocardial infarction, these agents confer a twice as high protective effect when compared to non-diabetic patients. However, most paradoxically, betablocking agents are used less frequently in diabetes. Control of hypertension is insufficient in most of the diabetic patients, probably because a combination of antihypertensive agents including betablockers is frequently needed to sufficiently control blood pressure but is not used in these patients. The fear of betablocker-associated side effects in diabetes may be partly responsible for the frequent antihypertensive mono-therapy and the resulting poor quality of blood pressure control among diabetic patients.
DESIGN: We have performed an analysis of the literature to assess whether possible adverse metabolic effects, a higher risk of hypoglycaemia or less nephroprotective effects of beta1-selective betablocking agents could justify the reticence in prescribing these antihypertensive agents to diabetic patients.
RESULTS: A thorough review of the literature does not indicate that beta1-selective betablocking agents have important adverse effects on glucose metabolism, prolong hypoglycaemia or mask hypoglycaemic symptoms. In diabetic nephropathy, betablockers are as nephroprotective as angiotensin converting enzyme inhibitors.
CONCLUSIONS: The unnecessary less frequent prescription of beta1-selective betablockers in diabetes mellitus may contribute to the higher cardiovascular mortality among these patients.