[An open comparative study of captopril + hydrochlorothiazide versus chlorthalidone for the treatment of mild and moderate primary hypertension].

PURPOSE

To compare the antihypertensive and metabolic effects of captopril combined with hydrochlorothiazide (C+HCTZ) versus chlorthalidone (CT) in mild and moderate primary hypertensive patients.

METHODS

Fifty five patients, without treatment or treated with 15 days placebo were randomized for treatment with the combination of captopril 50mg and hydrochlorothiazide 25mg (n = 29) against chlorthalidone (n = 26). The clinical evaluation was done during placebo and monthly throughout three months, and the laboratory tests were done before and at the end of the study.

RESULTS

The blood pressure were similar between groups during placebo period (C + HCTZ: 161 +/- 25/102 +/- 6-CT: 155 +/- 18/101 +/- 6 mmHg); the diastolic blood pressure decreases significantly at first month already in the group C + HCTZ (89 +/- 8 mmHg) compared to group CT (94 +/- 8 mmHg, p < 0.05). The percentile diastolic and mean blood pressure dropped, in average, 12% in C + HCTZ group and in CT varied between 7 (1st and 2nd month) to 11% (3rd month). Without statistical difference, the blood pressure normalization was obtained in 69% of the patients with the association captopril and diuretic and in 50% of the patients in the chlorthalidone group. It was observed a significant reduction of potassium in patients treated with chlorthalidone (4.2 +/- 0.7 to 3.7 +/- 0.4 mEq/L, p < 0.01) that was not observed with the captopril and the thiazide associated. The last treatment also significantly reduced the cholesterol levels (219 +/- 39 mg/dl to 202 +/- 39 mg/dl, p < 0.04).

CONCLUSION

Our results indicate that captopril combined with low diuretic dose normalize the blood pressure in 69% mild to moderate primary hypertensive patients, and acts faster than chlorthalidone in this control. In addition has metabolic benefits reducing cholesterol levels with no alteration in potassium levels.