Chronic pelvic pain in an interdisciplinary setting: 1-year prospective cohort

Abstract

Background: Chronic pelvic pain affects ∼15% of women, and presents a challenging problem for gynecologists due to its complex etiology involving multiple comorbidities. Thus, an interdisciplinary approach has been proposed for chronic pelvic pain, where these multifactorial comorbidities can be addressed by different interventions at a single integrated center. Moreover, while cross-sectional studies can provide some insight into the association between these comorbidities and chronic pelvic pain severity, prospective longitudinal cohorts can identify comorbidities associated with changes in chronic pelvic pain severity over time.

Objective: We sought to describe trends and factors associated with chronic pelvic pain severity over a 1-year prospective cohort at an interdisciplinary center, with a focus on the role of comorbidities and controlling for baseline pain, demographic factors, and treatment effects.

Study design: This was a prospective 1-year cohort study at an interdisciplinary tertiary referral center for pelvic pain and endometriosis, which provides minimally invasive surgery, medical management, pain education, physiotherapy, and psychological therapies. Exclusion criteria included menopause or age >50 years. Sample size was 296 (57% response rate at 1 year; 296/525). Primary outcome was chronic pelvic pain severity at 1 year on an 11-point numeric rating scale (0-10), which was categorized for ordinal regression (none-mild 0-3, moderate 4-6, severe 7-10). Secondary outcomes included functional quality of life and health utilization. Baseline comorbidities were endometriosis, irritable bowel syndrome, painful bladder syndrome, abdominal wall pain, pelvic floor myalgia, and validated questionnaires for depression, anxiety, and catastrophizing. Multivariable ordinal regression was used to identify baseline comorbidities associated with the primary outcome at 1 year.

Results: Chronic pelvic pain severity decreased by a median 2 points from baseline to 1 year (6/10-4/10, P < .001). There was also an improvement in functional quality of life (42-29% on the pain subscale of the Endometriosis Health Profile-30, P < .001), and a reduction in subjects requiring a physician visit (73-36%, P < .001) or emergency visit (24-11%, P < .001) in the last 3 months. On multivariable ordinal regression for the primary outcome, chronic pelvic pain severity at 1 year was independently associated with a higher score on the Pain Catastrophizing Scale at baseline (odds ratio, 1.10; 95% confidence interval, 1.00-1.21, P = .04), controlling for baseline pain, treatment effects (surgery), age, and referral status.

Conclusion: Improvements in chronic pelvic pain severity, quality of life, and health care utilization were observed in a 1-year cohort in an interdisciplinary setting. Higher pain catastrophizing at baseline was associated with greater chronic pelvic pain severity at 1 year. Consideration should be given to stratifying pelvic pain patients by catastrophizing level (rumination, magnification, helplessness) in research studies and in clinical practice.

Keywords: chronic pelvic pain; endometriosis; interdisciplinary; pain catastrophizing; prospective cohort; quality of life.