Background: Hypertension in patients with type 2 diabetes mellitus is a prevalent condition that leads to substantial morbidity and mortality.
Purpose: To evaluate the goals and optimal agents for treatment of hypertension in type 2 diabetes.
Data sources: Review of the medical literature
Study selection: Randomized trials that evaluated the pharmacologic treatment of hypertension in patients with diabetes and reported microvascular and macrovascular outcomes.
Data extraction: Studies were identified by using the Cochrane Library, MEDLINE, meta-analyses, review articles, and expert recommendation. The searches of the Cochrane Library and MEDLINE were performed in May 2000 and updated in April 2002. Data were abstracted to standardized forms by a single reviewer and were confirmed by a second reviewer.
Data synthesis: Treatment of hypertension in type 2 diabetes provides dramatic benefit. Target diastolic blood pressures of less than 80 mm Hg appear optimal; systolic targets have not been as rigorously evaluated, but targets of 135 mm Hg or less are reasonable. Studies that compare drug classes do not suggest obviously superior agents. However, it is reasonable to conclude that thiazide diuretics, angiotensin-II receptor blockers, and perhaps angiotensin-converting enzyme (ACE) inhibitors may be the preferred first-line agents for treatment of hypertension in diabetes. beta-Blockers and calcium-channel blockers are more effective than placebo, but they may not be as effective as diuretics, angiotensin-II receptor blockers, or ACE inhibitors; however, study results are inconsistent in this regard.
Conclusions: Treatment of hypertension in type 2 diabetes, with blood pressure goals of 135/80 mm Hg, provides dramatic benefits. Thiazide diuretics, angiotensin II receptor blockers, and ACE inhibitors may be the best first-line treatments, although other agents are usually necessary and goals may not be achieved even with three or four agents. Aggressive blood pressure control may be the most important factor in preventing adverse outcomes in patients with type 2 diabetes.