The role of catastrophizing in women with endometriosis-related chronic pelvic pain: a moderated mediation model

Study question Does pain catastrophizing mediate the relationship between pain interference and depression in women with endometriosis-related chronic pelvic pain (CPP)? Summary answer In women with endometriosis and CPP, catastrophizing mediates the association between pain interference and depression. What is known already CPP may significantly impact both quality of life (QoL) and psychological well-being of women with endometriosis. Pain catastrophizing, intended as the tendency to ruminate on pain, to amplify its negative effects and to perceive it as uncontrollable, is associated with worse psychophysical outcomes in different populations of patients with chronic pain. Study design: prospective single-cohort study. Size: 130 patients with endometriosis and CPP Duration: from September 1st, 2022 and December 31st, 2024 Objective: to assess a possible correlation between pain interference on QoL, catastrophizing, and depression in women with endometriosis. Participants/materials, setting, methods Setting: Endometriosis Outpatient Service -Policlinico Umberto I- Rome Inclusion criteria: endometriosis and CPP Exclusion criteria: history of anxiety/depression, antidepressant drug treatment. Methods: Patients underwent medical history, gynecological examination, transvaginal ultrasound, and psychological consultation. Pain symptoms were assessed using VAS-score. Patients completed Pain Interference Subscale of the Multidimensional Pain Inventory (MPI), Pain Catastrophizing Scale, and Patient Health Questionnaire-9 (MPH-9). A moderated mediation model was tested, considering pain interference as predictor, depressive symptoms as outcomes, and catastrophizing as mediator. Main results and the role of chance Average age was 33.5 ± 8.11 years old. All patients reported dysmenorrhea (average VAS score 7.1 ± 2.1) and CPP (average VAS score 7.9±1.8). Ninety-nine patients (76.1%) had deep dyspareunia. All patients had ovarian endometriomas (average size 32.1 mm ± 16.4 mm). Seventy-two patients (55.3%) had deep infiltrating endometriosis (average size 7.8 mm ± 3.6 mm). The intensity of CPP moderated both the association between pain interference and catastrophizing (p = 0.008) and the association between catastrophizing and depression (p = 0.014). An indirect association between pain interference and depression was significant (p = 0.005) only in patients with deeper CPP (VAS 7-10). No statistically significant correlation between the size and/or the site of lesions and psychological outcomes was found. Limitations, reasons for caution The main limitation of the study is the low number of participants. Data should be confirmed, including a larger sample of patients. Wider implications of the findings In women with endometriosis and CPP, catastrophizing mediates the association between pain interference and depression. Therefore, it might represent a suitable objective of intervention to improve the negative impact of pain on health-related QoL and on the psychological well-being of affected patients.