Pelvic pain comorbidities associated with quality of life after endometriosis surgery

Background After endometriosis surgery, pain can persist or recur in a subset of patients. A possible reason for persistent pain after surgery is central nervous system sensitization and associated pelvic pain comorbidities. Surgery addresses the peripheral component of endometriosis pain pathophysiology (by lesion removal) but may not treat this centralized pain. Therefore, endometriosis patients with pelvic pain comorbidities related to central sensitization may experience worse pain-related outcomes after surgery, such as lower pain-related quality of life. Objective This study aimed to determine whether baseline (preoperative) pelvic pain comorbidities are associated with pain-related quality of life at follow-up after endometriosis surgery. Study Design This study used longitudinal prospective registry data from the Endometriosis Pelvic Pain Interdisciplinary Cohort at the BC Women’s Centre for Pelvic Pain and Endometriosis. Participants were aged ≤50 years with confirmed or clinically suspected endometriosis, and underwent surgery (fertility-sparing or hysterectomy) for endometriosis pain. Participants completed the pain subscale of the Endometriosis Health Profile-30 quality of life questionnaire preoperatively and at follow-up (1–2 years). Linear regression was performed to measure the individual relationships between 7 pelvic pain comorbidities at baseline and follow-up Endometriosis Health Profile-30 score, controlling for baseline Endometriosis Health Profile-30 and type of surgery received. These baseline (preoperative) pelvic pain comorbidities included abdominal wall pain, pelvic floor myalgia, painful bladder syndrome, irritable bowel syndrome, Patient Health Questionnaire 9 depression score, Generalized Anxiety Disorder 7 score, and Pain Catastrophizing Scale score. Least absolute shrinkage and selection operator regression was then performed to select the most important variables associated with follow-up Endometriosis Health Profile-30 from 17 covariates (including the 7 pelvic pain comorbidities, baseline Endometriosis Health Profile-30 score, type of surgery, and other endometriosis-related factors such as stage and histologic confirmation of endometriosis). Using 1000 bootstrap samples, we estimated the coefficients and confidence intervals of the selected variables and generated a covariate importance rank. Results The study included 444 participants. The median follow-up time was 18 months. Pain-related quality of life (Endometriosis Health Profile-30) of the study population significantly improved at follow-up after surgery (P