Effects of nitrendipine on plasma levels of insulin and glucose in patients with essential hypertension

Treatment of diabetic patients with hypertension

This review attempts to highlight the potential of calcium-channel blockers in the prevention of sequelae of diabetes mellitus and hypertension in patients who have both disorders. Evidence-based medicine is driven by the results of randomized, clinical trials. Major contributions were therefore derived from post hoc analyses of the diabetic patients enrolled in placebo-controlled trials, such as Systolic Hypertension in the Elderly Program (SHEP), Systolic Hypertension in Europe (Syst-Eur), and Systolic Hypertension in China (Syst-China), and stepped-care blood-pressure-oriented trials, such as the Hypertension Optimal Treatment (HOT) and United Kingdom Prospective Diabetes Study (UKPDS). Several studies, such as the Fosiniprl; versus Amlodipine Cardiovascular Events Trial (FACET) and Appropriate Blood Pressure Control in Diabetes (ABCD) Trial, have compared the relative merits of angiotensin-converting enzyme and calcium-channel blockers in preserving renal function and metabolic balance in diabetic patients with hypertension, but their publications focused on cardiovascular disorders, which were only secondary end points. On balance, the articles reviewed prove that dihydropyridine calcium-channel blockers score particularly well in the prevention of cardiovascular complications in diabetic patients with hypertension.

Effects of calcium-channel blockade in older patients with diabetes and systolic hypertension. Systolic Hypertension in Europe Trial Investigators

BACKGROUND

Recent reports suggest that calcium-channel blockers may be harmful in patients with diabetes and hypertension. We previously reported that antihypertensive treatment with the calcium-channel blocker nitrendipine reduced the risk of cardiovascular events. In this post hoc analysis, we compared the outcome of treatment with nitrendipine in diabetic and nondiabetic patients.

METHODS

After stratification according to center, sex, and presence or absence of previous cardiovascular complications, 4695 patients (age, > or =60 years) with systolic blood pressure of 160 to 219 mm Hg and diastolic pressure below 95 mm Hg were randomly assigned to receive active treatment or placebo. Active treatment consisted of nitrendipine (10 to 40 mg per day) with the possible addition or substitution of enalapril (5 to 20 mg per day) or hydrochlorothiazide (12.5 to 25 mg per day) or both, titrated to reduce the systolic blood pressure by at least 20 mm Hg and to less than 150 mm Hg. In the control group, matching placebo tablets were administered similarly.

RESULTS

At randomization, 492 patients (10.5 percent) had diabetes. After a median follow-up of two years, the systolic and diastolic blood pressures in the placebo and active-treatment groups differed by 8.6 and 3.9 mm Hg, respectively, among the diabetic patients. Among the 4203 patients without diabetes, systolic and diastolic pressures differed by 10.3 and 4.5 mm Hg, respectively, in the two groups. After adjustment for possible confounders, active treatment was found to have reduced overall mortality by 55 percent (from 45.1 deaths per 1000 patients to 26.4 deaths per 1000 patients), mortality from cardiovascular disease by 76 percent, all cardiovascular events combined by 69 percent, fatal and nonfatal strokes by 73 percent, and all cardiac events combined by 63 percent in the group of patients with diabetes. Among the nondiabetic patients, active treatment decreased all cardiovascular events combined by 26 percent and fatal and nonfatal strokes by 38 percent. In the group of patients receiving active treatment, reductions in overall mortality, mortality from cardiovascular disease, and all cardiovascular events were significantly larger among the diabetic patients than among the nondiabetic patients (P=0.04, P=0.02, and P=0.01, respectively).

CONCLUSIONS

Nitrendipine-based antihypertensive therapy is particularly beneficial in older patients with diabetes and isolated systolic hypertension. Thus, our findings do not support the hypothesis that the use of long-acting calcium-channel blockers may be harmful in diabetic patients.