Design: Systematic review

Setting: N/a

Patients or Participants: Inclusion criteria were studies reporting on women with endometriosis with and without CSS. Exclusion criteria were studies primarily focused on non-endometriosis pelvic pain syndromes.

Interventions: A comprehensive literature search using MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Review, Science Citation Index Expanded, and Emerging Sources Citation Index was conducted without language or date restrictions. The search strategy utilized Medical Subject Headings (MeSH) and EMTREE terms to capture concepts related to central sensitization, endometriosis, and associated symptoms like dysmenorrhea. Interventions in the reviewed studies included medical treatment, physiotherapy, or surgery.

Measurements and Main Results: A total of 1821 abstracts were identified, and 259 full texts were reviewed for eligibility. Four studies met inclusion criteria, and two studies reported on the same cohort. Heterogeneity of the studies was evident. Catastrophization was defined using different scales (Central Sensitization Inventory > 40, Pain Catastrophizing Scale > 30, and Coping Strategies Questionnaire score 5 or 6). The percentage of patients with CSS at baseline ranged from 11.3% to 58.2%. Treatment outcomes were measured differently, including Visual Analog Scale >5 at follow-up, subjective ineffectiveness of hormone therapy, and elevated Short Form McGill Pain Questionnaire responses one year after surgery. Despite this heterogeneity, all studies reported worse outcomes in patients with higher baseline catastrophization.

Conclusion: CSS frequently co-occurs in women with endometriosis, and studies show worse pain outcomes when these conditions coexist. This is important to consider during counseling and decision-making. Efforts to standardize reporting of CSS is beneficial for future research.