Pure stress urinary incontinence: analysis of prevalence, estimation of costs, and financial impact.

BACKGROUND: The prevalence of pure stress urinary incontinence (P-SUI) and the role of urodynamic investigation (UDI) prior to surgery for stress urinary incontinence (SUI) is debated. Since the exact prevalence of P-SUI is not clear, its clinical and economic impact is not well defined. The aims of this study were to evaluate the prevalence of P-SUI in a population of women who underwent UDI for urinary incontinence (UI), also assessing: 1) the correspondence between clinical diagnosis of P-SUI and urodynamic findings; 2) the analysis of costs in terms of UDI and eventually post-UDI avoided surgical procedures. METHODS: A single cohort of women who underwent UDI for UI between January 2012 and July 2016 was prospectively collected and retrospectively analyzed. Clinical P-SUI was defined by the strict criteria of the International Continence Society. For each patient, history, physical examination and UDI were collected. The correspondence between clinical and urodynamic findings of P-SUI was analyzed. The rate of clinical P-SUI changed after performing UDI and the number of unnecessary intervention after UDI were reported. A wide cost analysis of UDIs, and the amount of surgical procedures that were believed unnecessary after UDI was reported. RESULTS: Stress urinary incontinence was present in 323/544 (59.4%) patients. The prevalence of clinical P-SUI was 20.7% (67/323), while the prevalence of complicated SUI (C-SUI) was 79.3% (256/323). After UDI, diagnosis of P-SUI decreased to 18.3% (59/232). In 10.2% of cases (6/59) the scheduled middle urethral sling (MUS) was suppressed after the UDI results because 3/6 cases had detrusor overactivity and urge incontinence, in 2/6 cases SUI was treated with a conservative management, in 1/6 case an important voiding dysfunction was detected. Considering the national reimbursement in our country, the cost of each UDI was 296.5 euros and the total amount was 17,493.5 euros. So far the surgery-related savings covered 61.7-105.0% of the costs of total number of UDIs performed in the uncomplicated patients. CONCLUSIONS: The prevalence of clinical P-SUI is relevant, involving about 20% of women with clinical SUI. Although the correspondence between clinical and urodynamic diagnosis was high, we demonstrated that UDI may help in some cases to avoid an inappropriate surgical treatment. Therefore, UDI prior to SUI surgery should be considered to achieve a correct diagnosis and a proper therapeutic strategy.