Comparison of the efficacy and tolerability of telmisartan and enalapril in patients of mild to moderate essential hypertension

Background: Theoretically, angiotensin II receptor blockers (ARBs) have certain advantages over angiotensin-converting enzyme inhibitors, but the contribution of these advantages to the clinical effect of ARBs is not known. Objective: To compare the efficacy and tolerability of telmisartan with enalapril in patients of essential hypertension. Materials and Methods: Patients of mild to moderate hypertension were randomized to receive either 40 mg of telmisartan or enalapril 10 mg once a day orally for 12 weeks. At each visit, the systolic blood pressure (BP), diastolic BP and heart rate of each patient were recorded. Investigations such as hemogram hemoglobin, total leucocytes count (Hb, TLC), serum creatinine, serum glutamic oxaloacetic transaminase, serum glutamic pyruric transaminase (SGOT, SGPT) random blood sugar and urine examination were performed at baseline and after 12 weeks of the treatment period. Results: The mean reduction in systolic BP in the telmisartan/enalapril group was 26.38 +/- 10.98/26.74 +/- 8.24 mmHg while the mean reduction in diastolic BP in the telmisartan/enalapril group was 14 +/- 2.98/9.71 +/- 4.23 mmHg, respectively, at 12 weeks. When the reduction in systolic BP in the two groups was compared, there was no significant difference between the groups (P > 0.05). However, the mean reduction in diastolic BP achieved with telmisartan at 12 weeks was significantly higher (P < 0.001) than that achieved with enalapril after the corresponding period. The overall frequency of adverse-effects was similar. However, in the enalapril group, the incidence of dry cough was higher as compared to that in the telmisartan group (11.43% vs. 0%, respectively; P < 0.05). Conclusion: Telmisartan produces a greater reduction in diastolic BP than enalapril and is free from the adverse-effect of dry cough that is commonly encountered with enalapril.