First-line antimuscarinic monotherapy is safe and effective in men with predominant storage symptoms of the lower urinary tract

ObjectiveTo investigate the safety and efficacy of first-line antimuscarinic monotherapy for men with predominant storage symptoms in the lower urinary tract based on the International Prostate Symptom Score (IPSS) voiding-to-storage subscore ratio (IPSS-V/S).Materials and MethodsWe conducted a prospective open-label study of first-line tolterodine (4 mg daily) monotherapy in 132 men (age 41–90 years) with a total IPSS (IPSS-T) ≥ 8 and IPSS-V/S ≤ 1. The IPSS storage subscore (IPSS-S), voiding subscore, IPSS-T, quality of life (QoL), maximal flow rate, voided volume, and post-void residual urine (PVR) were evaluated after treatment for 1 month and 3 months.ResultsThe treatment results were satisfactory (global response assessment ≥ 1) in 103 men (78.0%). Mean IPSS-T, IPSS-S, nocturnal frequency, and QoL improved significantly. No patient developed acute urinary retention. However, mean PVR increased significantly (from 51.8 to 63.9 mL), especially among patients older than 70 years. The treatment results did not differ significantly between patients with a total prostate volume (TPV) ≥ 30 mL and those with TPV < 30 mL.ConclusionFirst-line antimuscarinic monotherapy is safe and effective for men with IPSS ≥ 8 and IPSS-V/S ≤ 1. The treatment results were similar in men with TPV larger or smaller than 30 mL. However, we recommend that first-line antimuscarinic monotherapy in men older than 70 years should be administered with caution.