Women with cystocele may be associated with detrusor underactivity (DU) or bladder outlet obstruction (BOO). However, the impact of cystocele repair on the rates of DU and BOO remains obscure. Thus, the aim of this study is to (1) elucidate the prevalence of DU and BOO in each age group and (2) elucidate the impact of cystocele repair on the rates of DU and BOO.

Between November 2010 and September 2018, all women with ≥ POP-Q stage II cystocele who visited the urogynecological department of a medical center for urodynamic evaluation were reviewed. Those women who have no complete data of maximum flow rate (Qmax), voided volume, post void residual volume (PVR) and detrusor pressure at maximum flow rate (PdetQmax) were excluded from this study. 
The DU was defined when the PdetQmax was less than 20 cmH2O, the Qmax was less than 15 mL/s, and the bladder voiding efficiency (BVE) was less than 90 % [1]. The BOO was defined when the PdetQmax was not less than 40 cmH2O, and the Qmax was less than 12 mL/s [1]. BVE = voided volume / (voided volume + PVR) x 100%. Those women without DU or BOO were allocated to the non-DU/BOO group.
STATA software was used for statistical analysis. Wilcoxon signed-rank test and McNemar’s test were used for statistical analysis as appropriate. P < 0.05 was considered as statistically significant.

A total of 623 women were included in this study. Forty-four (7%) women were found to have DU, and seventeen (3%) women were found to have BOO. The highest rate (11%, 4/35) of DU was in the age of >81 year-old, and the highest rate (6%, 2/35) of BOO was also in the age of >81 year-old. 
Among the 623 women, 314 women had clinical and urodynamic paired data before and after cystocele repair. An increase of DU (7% (21/314) vs. 15% (46/314), p=0.0007) was found after cystocele repair. However, the rates of BOO did not differ between preoperative and postoperative data (4% (12/314) vs. 3% (8/314), p=0.35). However, bladder contractility index and bladder outlet obstruction index did not differ between the baseline and postoperative data.
A decrease of pad weight (21.1±35.4 vs. 8.5±23.0 g, p<0.0001), PVR (49±36  vs. 40±33 mL, p<0.0001), maximum urethral closure pressure (70.8±38.1 vs. 53.7±25.6 cmH2O, p=0.0008), functional profile length (2.5±1.4 vs. 2.2±0.7 cm, p<0.0001) and pressure transmission ratio at maximum urethral pressure (113±54 % vs. 102±28 %, p=0.02), and an increase in the strong-desire volume (256±54 vs. 266±49 mL, p=0.0002) were found after cystocele repair.
Besides, the scores of Urgency Severity Scales, Overactive Bladder Symptoms Score, Urogenital Distress Inventory short form and Incontinence Impact Questionnaire improved after cystocele repair. Except nocturnal enuresis, the severity of all bladder symptoms in the King’s Health Questionnaire (i.e., frequency, nocturia, urgency, urge incontinence, stress urinary incontinence, intercourse incontinence, waterworks incontinence, bladder pain and voiding difficulty) were all improved after cystocele repair. Besides, all domains (i.e., general health perception, incontinence impact, role limitation, physical limitation, social limitation, personal relationships, emotion, sleep/energy and severity measures) in the King’s Health Questionnaire were also improved.
In addition, nocturia episodes (4.6±3.5 vs. 4.1±3.1, p=0.03), daytime frequency (27±9 vs. 23±8, p<0.0001), urgency episodes (6±9.4 vs. 2.9±6.8, p<0.0001) and incontinence episodes (1.4±4.6 vs. 0.3±1.0, p=0.005) in the three-day bladder diaries were improved after cystocele repair.

The rate of DU increased after cystocele repair, despite of no change in the bladder contractility index. In addition, the rate of BOO and the bladder outlet obstruction index did not change after surgery. Besides, most low urinary tract symptoms (such as nocturia, daytime frequency, urgency and incontinence) improved after surgery.

Seven percent of women with cystocele have DU, and three percent of women with cystocele have BOO. The rates of BOO and DU tend to be higher with aging. After cystocele repair, the rate of DU might increase despite of no difference in the bladder contractility index; nonetheless, the rate of BOO and the bladder outlet obstruction index did not change after surgery.

Gammie A, Kaper M, Dorrepaal C, Kos T, Abrams P. Signs and Symptoms of Detrusor Underactivity: An Analysis of Clinical Presentation and Urodynamic Tests From a Large Group of Patients Undergoing Pressure Flow Studies. Eur Urol 2016;69:361-9.