Objectives

To investigate the association of hiatal area (HA), bladder neck mobility, and urethral mobility during the cough stress test (CST) with stress urinary incontinence (SUI).

Methods

This was a prospective study of 110 continent and 190 incontinent women using transperineal ultrasound. HA, bladder neck mobility, and the mobility of six points along the urethra (Vectors 1–6) were measured. The cohort was randomly divided at a ratio of 2:1 into a training cohort and a validation cohort. The correlations of HA with bladder neck mobility, urethral mobility, and SUI were tested. The predictive model was yielded by fisher linear discriminant analysis and receiver operating characteristics to assess the parameters' ability to predict SUI.

Results

Valid data were collected from 177 incontinent women and 105 continent women. Significant differences were identified in HA, body mass index (BMI), funneling, bladder neck mobility, and Vectors 1–6 between them. HA was positively correlated to bladder neck mobility. In the training cohort, bladder neck position on Valsalva, Vectors 3, and BMI had the area under curves of 0.74, 0.69, and 0.66 (all P < 0.001); Funneling and Vector 3 had odds ratios of 18.96 and 3.65 (all P < 0.001), for predicting SUI. The predictive model incorporating funneling, Vectors 3, and BMI provided the best performance in predicting SUI in both cohorts.

Conclusion

The larger the HA was, the higher the bladder neck mobility. However, it was mid-urethral mobility rather than bladder neck mobility that performed best at predicting SUI.