The prevalence of urinary incontinence and associated risk factors in Taiwanese women with lower urinary tract symptoms

Background: To analyze the urodynamic-defined prevalence of urinary incontinence and the associated risk factors in Taiwanese women with lower urinary tract symptoms (LUTS). Methods: We reviewed the medical records of 4,470 women who were referred to our urodynamic center between January 1999 and May 2003. Their records including a comprehensive medical history, physical examination, bladder diary and results of multi-channel urodynamic testing were analyzed. Results: 3,161 of 4,470 women recruited were eligible for the analyses. The distribution of urodynamic prevalence in 3,161 women revealed that urodynamic stress incontinence (USI) was 1,755/3,161 (55.5%), detrusor overactivity (DO) 231/3,161 (7.3%), mixed incontinence (MI) 142/3,161 (4.5%), voiding dysfunction (VD) 793/3,161 (25.1%) and normal result (N) 240/3,161 (7.6%). The highest prevalence of USI was observed in women aged 40-49 (40.3%) and the prevalence of DO and MI seemed to be lower as compared with the literature reports. Linear regression analysis showed parity (p < 0.001) and three urodynamic study (UDS) variables [maximum free flow rate (p = 0.003), maximum urethral closure pressure (p = 0.003) and functional profile length (p = 0.014)] were significantly related to the urinary incontinence in women with LUTS. Menopause (p = 0.865) had no impact on the urinary incontinence. Conclusion: Risk factors contributing to Taiwanese women with LUTS to develop urinary incontinence included multiparity and three specific parameters observed during UDS. Of interest, our data also indicated 25% of patients were diagnosed as voiding dysfunction deserved future study.