A comparison of the hypotensive effects of captopril and atenolol in the treatment of hypertension in diabetic patients.

In a double-blind, randomized, cross-over study in 23 diabetic patients, insulin treated (N = 11) or noninsulin treated (N = 12), with mild to moderate hypertension, the hypotensive effects of captopril and atenolol were compared. Five patients had overt diabetic nephropathy. All patients received 50 mg twice daily of either drug. Treatment periods lasted 6 weeks and were preceded and separated by a placebo period. Two patients dropped out, one because of intermittent claudication during atenolol, one with cardiac arrhythmia during placebo. Blood pressure was reduced from 165 +/- 5/96 +/- 1 to 154 +/- 5/89 +/- 2 mmHg (mean +/- SEM: P less than 0.01) during captopril and from 171 +/- 5/98 +/- 1 to 159 +/- 6/89 +/- 2 mmHg (P less than 0.01) during atenolol. These antihypertensive effects are not significantly different. There was a wide inter- and intraindividual variation in hypotensive response to both drugs, which may have important consequences for treatment strategies. No consistent differences between insulin and noninsulin treated patients were seen. Parameters of glycemic control did not change during any therapy, neither in insulin treated nor in non-insulin treated patients. Albuminuria and renal function did not change. During captopril treatment one patient complained of a non-productive cough. Two patients experienced a severe hypoglycemic reaction during atenolol. No other major side-effects were seen. In conclusion, this study showed equal hypotensive effectivity of 100 mg captopril and 100 mg atenolol daily in hypertensive diabetics, without evident effect on glycemic control.