A randomised comparison of the effects of nebivolol and atenolol with and without chlorthalidone on the sexual function of hypertensive men

Background and objective: Erectile dysfunction, which is common in men with hypertension, has been reported as a common adverse effect of many anti hypertensive drug classes, including P-blockers and diuretics. Atenolol and nebivolol are both beta(1)-selective blockers, but nebivolol is a new-generation compound with nitric oxide-mediated vasodilating activity. The aim of the study was to compare the effects of nebivolol and atenolol +/- chlorthalidone on the sexual function of hypertensive men. Methods: A total of 131 male patients (mean age 47.3 +/- 4.6 years) with newly diagnosed hypertension were included in the study. All the patients were married and had not previously experienced any erectile dysfunction. After a 4-week placebo run-in period, patients were randomised to receive 12 weeks therapy with nebivolol 5 mg/day (n = 43), atenolol 50 mg/day (n = 44), or atenolol 50 mg/ day + chlorthalidone 12.5 mg/day (n = 44), according to a double-blind design. After 4 weeks of treatment, drug dosage could be doubled in patients not responding to therapy. Erectile function (instances of successful intercourse/ month) was assessed by means of a questionnaire at the end of the placebo run-in period (baseline) and at the end of double-blind treatment. Blood pressure was also assessed at these times. Results: At the end of the 12-week, double-blind treatment period, the mean number of episodes of satisfactory sexual intercourse per month was significantly decreased from baseline in the groups receiving atenolol (from 7.0 to 3.7; p < 0.01) and atenolol + chlorthalidone (from 6.4 to 2.8; p < 0.01). In contrast, the mean number of episodes of satisfactory sexual intercourse per month remained constant in the group of patients receiving nebivolol (6.4 during the baseline assessment and 6.0 during the last month of treatment). Blood pressure and heart rate were significantly decreased from baseline in all treatment groups. Conclusion: Increased release of nitric oxide associated with nebivolol may counteract the detrimental effect of P-blockade on penile erection, thereby allowing maintenance of sexual activity in previously untreated hypertensive men compared with a significant decrease observed in the sexual activity of men receiving atenolol-based treatment.