The International Continence Society (ICS) defines overactive bladder syndrome (OAB) as urinary urgency, usually with urinary frequency and nocturia, with or without urgency urinary incontinence. The reported prevalence of OAB in women from European and USA population studies varies between 16.8% (1) and 33% (2) respectively. 

A potential contributory factor or cause for the OAB symptoms is a cystocele (descent of the posterior wall and/or of bladder neck into the anterior vaginal wall). This poor support of the bladder base may result in a premature activation of the sensory receptors concentrated at the trigone(3) and OAB symptoms which are not associated with detrusor overactivity (‘sensory urgency’). We therefore hypothesised, in patients with OAB symptoms, detrusor overactivity (DO) is less commonly demonstrated in patients with cystoceles than those without.

We retrospectively reviewed the VCMG results of 211 consecutive women with intractable OAB symptoms (increased daytime frequency, urgency or nocturia). Patients with known neurological pathology were excluded. We defined a cystocele as a posterior bladder wall and/or bladder neck below the inferior border of the pubic symphysis. All VCMG studies were performed in accordance with the ICS ‘Good Urodynamics Practice’ standard. 

The Fisher’s Exact test is used to determine if there is a statistically significant difference between the proportion of women with and without cystoceles demonstrating DO on urodynamics.

The mean age (±SD) was 48 ± 15 years. 93 of the 211 women were presented with a cystocele, 52 (55.9%) of which had DO during the VCMG investigation. Of the 118 women without cystoceles, 60 (50.8%) had DO during the VCMG investigation. The Fisher’s Exact (2 – sided) p value is 0.490. DO was only demonstrated in only 53% of our cohort.

Our study found that there was not a statistically significant difference in the distribution of women demonstrating DO on urodynamics with and without a cystocele. This finding suggests, premature activation of the sensory receptors in the bladder base is not associated with DO (‘sensory urgency’) and is unlikely to account for OAB symptoms in women with cystocele, more than for patients with adequate bladder support. More likely, as suggested by reports of OAB symptoms resolution following pelvic organ prolapse repair procedures, DO (early activation of the micturition reflex) and/or ‘sensory urgency’ may be caused by poor pelvic floor support.

DO was demonstrated in only 53% of women with non-neurogenic OAB symptoms. Patients with cystocele did not have a lower likelihood of demonstrating detrusor overactivity on UDS. Our finding suggests OAB symptoms in women are multi-factorial and accurate identifying of the root cause of LUTS is key to maximise efficacy of treatment.

C Temmla, SHeidlerb, A Ponholzerb, S Madersbache. Prevalence of the Overactive Bladder Syndrome by Applying the International Continence Society Definition, European Urology Volume 48, Issue 4, October 2005, Pages 622-627
KS Coynea, M Margolisa, ZS Kopp, SA Kaplanc. Racial Differences in the Prevalence of Overactive Bladder in the United States From the Epidemiology of LUTS (EpiLUTS) Study. Urology Volume 79, Issue 1, January 2012, Pages 95-101
KE Andersson. Bladder activation: afferent mechanisms. Urology 2002; 59: 43–50