Factors Associated with Severity of Irritable Bowel Syndrome Symptoms in Patients with Endometriosis.

OBJECTIVE: This study sought to examine factors associated with severity of irritable bowel syndrome (IBS) by using the Birmingham IBS symptom scale in patients presenting with endometriosis to a tertiary referral centre.

METHODS: A prospective research cohort of patients presenting to a tertiary referral centre for endometriosis was evaluated for the presence and severity of IBS between December 2013 and April 2015. Patients with endometriosis had a diagnosis of IBS by using the Rome III criteria and were evaluated for severity of IBS symptoms by using the Birmingham IBS symptom scale. Multifactorial variables, including stage of endometriosis at the time of previous surgery, clinical examination findings, mood disorder questionnaire scores, and lifestyle factors, were evaluated using the t test and Spearman rank correlation test.

RESULTS: A total of 194 of 373 (52%) women with confirmed endometriosis had a diagnosis of IBS. Factors associated with severity of IBS symptoms in patients with endometriosis included lower-stage endometriosis (P = 0.004), presence of mood disorders (P <0.001), tenderness on physical examination (P ≤ 0.001), a history of sexual assault (P ≤ 0.02), and presence of sleep disturbance (P ≤ 0.01). Evaluation of the subscales of the Birmingham IBS symptom scale revealed a strong association between the previously identified factors and the pain subscale.

CONCLUSION: Using the Birmingham IBS symptom scale, our study revealed more severe IBS symptoms in patients with lower-stage endometriosis and identified other variables highly associated with severity of IBS. Continued research is required to characterize further the clinical importance of IBS symptoms in patients with endometriosis-associated pelvic pain.