Spironolactone and altizide versus converting enzyme inhibitor (enalapril)

The safety and antihypertensive effectiveness of a fixed-dose combination form of spironolactone + altizide (S/A) were compared with those of enalapril, an angiotensin-converting enzyme inhibitor in a randomized, double-blind, parallel-group study of 186 patients with moderate essential hypertension. The 2 treatment groups were comparable in terms of age, gender, duration and severity of hypertension, diastolic blood pressure (BP), serum potassium and creatinine, and 24-hour urinary sodium excretion after a 4-week washout phase. After 8 weeks of treatment, both S/A and enalapril decreased BP significantly and to about the same extent. Enalapril, however, was more effective in decreasing supine diastolic BP in patients younger than age 50, whereas S/A yielded better results in those older than 50. Laboratory values were similar after both drugs were administered, and there were no clinically significant changes. The study demonstrated that S/A safely reduces elevated BP, particularly in older patients.