Central Sensitization Predicts Poorer Hormonal Treatment Response in Endometriosis: Study
Researchers have found in a new study that among women with endometriosis receiving hormonal therapy, higher pre-treatment Central Sensitization Inventory (CSI) scores and the presence of central sensitization (CS) were independently associated with hormonal treatment failure (HTF). This association was observed for chronic pelvic pain (CPP), deep dyspareunia, and dyschezia, suggesting that central sensitization may be an important predictor of poorer treatment outcomes and should be considered when planning individualized management strategies for endometriosis. The study was published in the Journal of Minimally Invasive Gynecology by Diego R. and colleagues.
The authors of the study conducted an observational prospective study where 114 consecutive symptomatic patients were recruited at a tertiary referral center during the period from January 10, 2024, to April 30, 2024. All subjects recruited for this study had to have never been on hormones previously, or they had to be at least three months post-washout. At the baseline assessment (T0), all subjects' endometriosis-related pain scores were measured by the NRS. The patients had to fill out the CSI questionnaire. All patients were administered conventional hormone treatments. At T1, which corresponded to the six-month mark of continuous medical therapy, the medical team performed a complete reassessment of all pain scores by using the NRS.
Hormonal therapy failure (HTF) was identified as obtaining less than a 30% reduction of the NRS score for any symptom between baseline and six-month follow-up. In order to find the connections between the continuous CSI scores, and/or established central sensitization (CSI score equal or above 40) and treatment failure in distinct symptoms, univariate and multivariate logistic regression models were used.
Key findings:
- A baseline average continuous CSI score of 35.87 was observed in the tracked cohort, with 46 subjects (40.4% of the total group) qualifying for central sensitization.
- Both high baseline CSI scores and central sensitization were found to be strongly associated with chronic pelvic pain, producing a univariate odds ratio of 1.046 and multivariable odds ratio of 3.058.
- A high CSI score and established sensitization had an effect on a higher treatment failure rate for painful intercourse, producing a univariable odds ratio of 1.047 and very strong multivariable odds ratio of 4.098.
- Dyschezia had a particularly strong association with central sensitization, with a high univariable odds ratio of 1.062 and very high multivariable risk failure odds ratio of 4.545.
- The proportion of patients that received cyclical hormonal therapy as part of standard clinical practice at the center was relatively small at 7.0%, while the majority of patients was placed under continuous suppression.
- Dysmenorrhea and dysuria were not included in the final analysis due to the fact that nearly all patients had amenorrhea on continuous therapies, and only 5.3% of the subjects had bladder pain.
To conclude, high CSI scores before treatment and having CS among patients suffering from endometriosis and undergoing hormonal treatment were associated independently with HTF due to CPP, dyspareunia and dyschezia. The results obtained are convincing, as the research lasted for six months prospectively. The research is the basis for modern gynecology as it proves the necessity to consider chronic pelvic pain in terms of endocrine and neurological processes.
Reference:
Raimondo, D., Bertoldo, L., Aguzzi, A., Ramelli, G., Arcilesi, M., Maletta, M., Doglioli, M., Neola, D., Paccapelo, A., Scarperi, S., Cobellis, L., Seracchioli, R., & Raffone, A. (2026). Central sensitization and hormonal therapy failure for endometriosis-related pain symptoms: a prospective study. Journal of minimally invasive gynecology, S1553-4650(26)00345-6. Advance online publication. https://doi.org/10.1016/j.jmig.2026.06.028
