The aim of this study was to compare sexual activity and plasma testosterone levels of hypertensive men with those of healthy normotensive controls. We investigated 110 newly diagnosed, never treated hypertensive (blood pressure [BP] > or = 140/95 mm Hg) men and 110 healthy normotensive (diastolic BP <90 mm Hg) men. All of them were aged 40 to 49 years, married, without any previous sexual dysfunction, nondiabetic, nonobese (body mass index <28 kg/m2), nonsmoking, and not taking any drug. All subjects were evaluated in the morning after an overnight fast. Clinical evaluation included BP, body weight, and height measurements, determination of testosterone, and an interview about sexual activity, assessed as number of sexual intercourse episodes per month. Hypertensive men presented a 25% reduction in sexual activity as compared to normotensive men (5.9 +/- 2.6 v 7.9 +/- 2.5 sexual intercourse episodes per month, respectively, P < .01) and a 12% reduction in testosterone levels (510.6 +/- 151.9 ng/dL v 578.6 +/- 146.8 ng/dL, P < .01). In both normotensive and hypertensive men Pearson's correlation analysis showed a significant positive correlation between testosterone levels and sexual activity and a significant negative correlation between testosterone and age and between testosterone and BP values. Multiple regression analysis confirmed a significant inverse relationship between testosterone and age in normotensive men, whereas only a nonsignificant trend was found in the hypertensive ones. In addition, a significant inverse correlation between testosterone and BP levels was confirmed in hypertensive men limited to systolic BP, whereas a nonsignificant trend was observed in the normotensive controls. In conclusion, these findings suggest a relationship between essential hypertension and impaired testosterone levels in men. The elucidation of the nature of such a relationship and its physiologic and clinical significance needs further investigation.