Efficacy of desmopressin in the treatment of nocturia: a double-blind placebo-controlled study in men.

OBJECTIVE To investigate the efficacy and safety of oral desmopressin in the treatment of nocturia in men. PATIENTS AND METHODS Men aged >/=18 years with verified nocturia (>or=two voids/night) and nocturnal urine production greater than their maximum functional bladder capacity were recruited. A 3-week dose-titration phase established the optimum desmopressin dose (0.1, 0.2 or 0.4 mg). After a 1-week 'washout' period, patients who responded in the dose-titration period were randomized to receive the optimal dose of desmopressin or placebo in a double-blind design for 3 weeks. RESULTS In all, 151 patients entered the double-blind period (86 treated with desmopressin, 65 with placebo). In the desmopressin group 28 (34%) patients and in the placebo group two (3%) patients (P<0.001) had fewer than half the number of nocturnal voids relative to baseline; the mean number of nocturnal voids decreased from 3.0 to 1.7 and from 3.2 to 2.7, respectively, reflecting a mean decrease of 43% and 12% (P<0.001). The mean duration of the first sleep period increased by 59% (from 2.7 to 4.5 h) in the desmopressin group, compared with an increase of 21% (from 2.5 to 2.9 h) in the placebo group (P<0.001). The mean nocturnal diuresis decreased by 36% (from 1.5 to 0.9 mL/min) in the desmopressin group and by 6% (from 1.7 to 1.5 mL/min) in the placebo group (P<0.001). The mean ratio of night/24-h urine volume decreased by 23% and 1% (P<0.001), and the mean ratio of night/day urine volume decreased by 27% and increased by 3% (P<0.001) for the desmopressin and placebo groups, respectively. In the double-blind treatment period, similar numbers of patients had adverse events; 15 (17%) patients in the desmopressin and 16 (25%) patients in the placebo group. Most adverse events were mild. Serum sodium levels were <130 mmol/L in 10 (4%) patients and this occurred during dose-titration. CONCLUSIONS Orally administered desmopressin is an effective and well-tolerated treatment for nocturia in men.