A Systematic Review of the Prevalence of Overactive Bladder in Women with Non-Urinary Tract Endometriosis and the Effect of Endometriosis Surgery on Symptoms of Overactive Bladder

Introduction and hypothesis: Overactive bladder (OAB) is characterised by urinary urgency, with or without incontinence, often accompanied by daytime frequency and nocturia, in the absence of urinary tract infection or other identifiable causes. Population studies estimate the prevalence of OAB at 12.8% (EPIC study), increasing with age, reaching up to 43% after age 40. Endometriosis affects about 10% of women of reproductive age. Both OAB and endometriosis are chronic and negatively impact women's quality of life. They appear to share a common pathophysiology related to central sensitisation. We hypothesised that OAB and endometriosis might co-exist, and surgical excision of endometriosis could alleviate OAB symptoms. We aimed to assess the prevalence of OAB in patients with endometriosis and examine the effect of endometriosis surgery on OAB symptoms.

Methods: A systematic search of MEDLINE, PubMed, Embase, and CINAHL-Plus identified studies reporting on endometriosis and OAB or overlapping conditions such as interstitial cystitis. Studies on bladder or ureteric endometriosis were excluded.

Results: Six studies (772 participants) were included. The prevalence of OAB in endometriosis patients ranged from 9.4% (Brazil) to 32% (France). OAB diagnosis varied, with tools such as International Consultation of Incontinence Modular Questionnaire on Female Lower Urinary Tract Symptoms, Core Lower Urinary Tract Symptom Score, Bristol Female Lower Urinary Tract Symptoms, and urodynamics. Surgical outcomes were inconsistent, with no improvement in three studies, equivocal in one, and worsened in another.

Conclusion: Overactive bladder and non-urinary tract endometriosis may co-occur in 20.5% of patients, with surgery showing variable effects on OAB symptoms. Further standardised global research is warranted to fill in evidence gaps such as whether pre-operative desensitisation could improve surgical and quality-of-life outcomes.