Alpha-blockers improve lower urinary tract symptoms associated with benign prostatic obstruction. Nocturia, a storage symptom, is a common complaint in men. However, it does not fully respond to α-blocker therapy, likely due to its multifactorial pathophysiology. We evaluated the efficacy and safety of desmopressin as add-on therapy for refractory nocturia in men previously treated with an α-blocker for lower urinary tract symptoms.
Eligible patients were men 50 years old or older with lower urinary tract symptoms and persistent nocturia despite α-blocker treatment for a minimum of 4 weeks. The optimum dose of oral desmopressin was determined during a 4-week dose titration period and this dose was maintained for 24 weeks. Flow volume charts, International Prostate Symptom Score total and subscores, uroflowmetry and post-void residual urine volume were assessed.
A total of 216 patients were enrolled in the study. Of these patients there were 158 (76%) with nocturnal polyuria, 15 (7.2%) with decreased nocturnal bladder capacity and 35 (16.8%) with nocturia due to both causes. The number of nocturnal voids significantly decreased from a baseline mean of 7.0 to 5.7 episodes for 3 days at the 24-week visit. The average International Prostate Symptom Score total and subscore significantly decreased by 4 weeks and were maintained at 24 weeks. In patients younger than 65 years, International Prostate Symptom Score voiding subscores were significantly improved at 24 weeks compared to those age 65 years or older.
Desmopressin add-on therapy for refractory nocturia in men previously treated with an α-blocker for lower urinary tract symptoms improved voiding symptoms as well as nocturia, storage symptoms.