Female urinary incontinence at orgasm: a possible marker of a more severe form of detrusor overactivity. Can ultrasound measurement of bladder wall thickness explain it?

INTRODUCTION: Coital incontinence (CI) during orgasm is a form of urinary incontinence possibly because of detrusor overactivity (DO), as the underlying pathophysiological condition. Women with this symptom usually show a pharmacological lower cure rate than those with DO alone. The ultrasound measurement of the bladder wall thickness (BWT) allows an indirect evaluation of detrusor muscle thickness, giving a potential index of detrusor activity. AIM: We wanted to understand if CI at orgasm could be a marker of severity of DO by comparing BWT in women with both DO and CI at orgasm vs. women with DO alone. In addition we aimed to confirm if CI during orgasm is related to antimuscarinics treatment failure. METHODS: This is a prospective cohort study performed in two tertiary urogynecological referral departments, recruiting consecutive patients seeking treatment for symptomatic DO. MAIN OUTCOME MEASURES: All patients were thoroughly assessed including physical examination, urodynamic evaluation, and BWT measurement according to the International Continence Society/International Urogynecological Association and ICI recommendations. Solifenacine 5 mg once daily was then prescribed and follow-up was scheduled to evaluate treatment. Multiple logistic regression (MLR) was performed to identify risk factors for treatment failure. RESULTS: Between September 2007 and March 2010, 31 (22.6%) and 106 (77.4%) women with DO with and without CI at orgasm were enrolled. Women complaining of CI at orgasm had significantly higher BWT than the control group (5.8 \ub1 0.6 mm vs. 5.2 \ub1 1.2 mm [P=0.007]). In patients with CI at orgasm, the nonresponder rate to antimuscarinics was significantly higher than controls (P=0.01). After MLR, CI at orgasm was the only independent predictor decreasing antimuscarinics efficacy (odds ratio [OR] 3.16 [95% CI 1.22-8.18], P=0.02). CONCLUSIONS: Women with DO and CI at orgasm showed a significantly higher BWT values and worse cure rates than women with DO alone. CI at orgasm could be a marker of a more severe form of DO