Prevalence of neuropathic pain in patients with symptomatic endometriosis: Assessment using the DN4 score

The mechanisms underlying pain in cases of endometriosis or chronic pelvic pain are complex, often involving various types of pain; mainly nociceptive pain, central sensitization, and neuropathic pain. Our main objective was to examine the prevalence of neuropathic pain in women with symptomatic endometriosis, and secondary, to explore the factors associated with this type of pain and to assess the prevalence of a positive PPSC score and a history of sexual violence within this population. This study is a retrospective, comparative, single-center cohort study conducted from September 2019 to January 2023. The presence of neuropathic pain was confirmed by a positive DN4 score, defined as greater than or equal to 4. The association with the following variables was studied: age, BMI, marital status, smoking, alcohol and drugs consumption, age at menarche, gestity, parity, duration of exposure to endometriosis, MRI locations, laparoscopy for endometriosis and post-laparoscopy r-ASRM classification, hormone treatment, associated symptoms, VAS, associated pathologies, infertility consultation, Pain Center consultation, EPH-5 score, positive PPSC score (≥5), and history of sexual violence. The prevalence of neuropathic pain was 44.1%. Younger age, being in a relationship, having a high EPH-5 score and undergoing laparoscopy for endometriosis are associated with neuropathic pain independently of other variables. Our study underscores the persistent high prevalence of neuropathic pain in endometriosis cases, emphasizing the importance of actively screening for it. Identifying neuropathic pain could prompt referrals to pain specialists, integrating it into a comprehensive multidisciplinary approach.