Clinical observations of the effect of antidiuretic hormone on nocturia in elderly men.

OBJECTIVE: To evaluate the effect of desmopressin on nocturia, based on patients' subjective scoring of nocturia, as desmopressin is widely used to treat nocturnal enuresis and nocturnal polyuria.

PATIENTS AND METHODS: We investigated a specific subgroup of 28 men with benign prostate obstruction and nocturia who were treated with desmopressin. Patients with nocturnal polyuria were excluded. All the patients were refractory to treatment with antimuscarinics or anticholinergics, e.g. oxybutynin, tolterodine, and propantheline bromide. We assessed the effect of desmopressin using a quantitative nocturia score and analysed its synergistic effect with alpha-blockers.

RESULTS: The mean frequency of nocturia was 6.1 before desmopressin and most (86%) patients had an improvement in nocturia within 1-12 weeks of treatment with desmopressin. There was a 43% reduction in nocturia after using desmopressin (P < 0.001). The correlation coefficient between the number of nocturnal voids and the reduction in nocturia after treatment with desmopressin was 0.756, indicating that the more severe the nocturia, the more effective was desmopressin.

CONCLUSIONS: Desmopressin is effective for refractory nocturia in elderly men with no nocturnal polyuria, and has limited side-effects.