Prevalence and Risk Factors of Central Sensitization in Women with Endometriosis

Study objective: To assess prevalence of central sensitization (CS) and its association with demographic and clinical factors in patients with endometriosis. Design: Single-center, observational, cross-sectional study. Setting: Tertiary center. Patients: Consecutive patients with endometriosis referred to the center from January 15, 2022, to April 30, 2022. Interventions: For each enrolled patient, demographic and clinical data were collected, and the presence of CS was measured using the CS Inventory questionnaire (score ≥40). Measurements and main results: Primary study outcome was CS prevalence, and secondary study outcomes were the associations between demographic and clinical factors and CS. The 95% confidence intervals for CS prevalence were obtained with Bayesian-derived Jeffreys method, and the associations between CS and demographic and clinical factors were evaluated with the chi-square test and Fisher's exact test, where appropriate. The variables significantly associated with CS were then included in a multivariable logistic regression model. The significance level was set at .05 for all analyses. During the study period, 285 eligible women were enrolled. CS prevalence was 41.4% (95% confidence interval, 35.8-47.2). At univariable analysis, infertility, moderate to severe pain symptoms (except for dyschezia), altered bowel movements, posterolateral parametrium involvement, hormonal therapy failure (HTF), and most of central sensitivity syndromes were significantly associated with CS occurrence. Multivariable analysis only confirmed the significant association of CS with moderate to severe chronic pelvic pain, posterolateral parametrium involvement, HTF, migraine or tension-type headache, irritable bowel syndrome, and anxiety or panic attacks. Conclusion: CS has a high prevalence in patients with endometriosis, especially in those with moderate to severe chronic pelvic pain, posterolateral parametrium involvement, HTF, and 3 central sensitivity syndromes (i.e. migraine or tension-type headache, irritable bowel syndrome, anxiety or panic attacks). Given the association with HTF, identifying CS through CS Inventory might be useful to counsel the patient and to choose multimodal treatment.