Prospective trial of sacral neuromodulation for refractory overactive bladder syndrome in Korean patients

Objectives: To evaluate the efficacy and safety of sacral neuromodulation for treating patients with refractory overactive bladder based on urodynamic data. Methods: Patients older than 18years of age, with overactive bladder symptoms refractory to conventional therapies were eligible. Patients with more than a 50% reduction in frequency, urgency, or urge incontinence symptoms during a 2-week test stimulation period retained the sacral neuromodulation. Voiding diaries, overactive bladder questionnaires, and urodynamic studies were performed before and 1year after sacral neuromodulation. Results: Forty patients received sacral neuromodulation and 31 patients of those were followed more than 1year. The mean age of the 31 patients was 54.2±15.4 (range, 30-76)years, and the mean duration of symptoms was 4.4±5.7 (range, 1-31)years. After 12months of sacral neuromodulation, significant decreases in the episodes of daily urgency (from 20.2 to 5.7, P<0.001), urgency incontinence (from 7.3 to 0.2; P=0.011), day time micturition (from 21.8 to 9.9; P<0.001), night time micturition (from 3.2 to 1.2; P=0.006) and in severity of urgency episodes (from 3.8 to 2.7; P=0.015) were observed compared to baseline. Significant increases occurred in bladder volume at the first unstable contraction (from 182.4±92.7 to 216.8±115.6mL), bladder volume at first desire to void (from 150.5±90.8 to 167.8±81.5mL), maximal cystometric capacity (from 260.7±120.4 to 291.7±124.3mL) and bladder volume at urgency sensation (from 182.4±92.7 to 208.2±106.6mL) (all P<0.05). Conclusions: Sacral neuromodulation is an effective and safe treatment for refractory overactive bladder.