Opioids for management of endometriosis associated pain: balancing effectiveness and quality of life

To identify risk factors for opioid use and assess the effect of opioids on women with endometriosis. A retrospective cohort study. A tertiary medical center. Women with confirmed or suspected endometriosis aged 18–45 years. Recruited participants completed a questionnaire including baseline demographic and general health data, a Brief Pain Inventory (BPI-Heb) and a Visual Analogue Scale assessing Endometriosis associated pain symptoms. Women using opioids were compared to women not using opioids. Women treated with opioids further completed a Visual Analogue Scale quesionniare of pain symptoms after using opioids, a questionnaire assessing side effects, and the Opioid Risk Tool for the assessment of addiction risk. Ninety-eight patients were included in the study. Of them, 49 were opioid users, and 49 were non-opioid users. One unit increase in overall pain was associated with a 28% increased risk of opioid use [OR = 1.28, 95% CI 1.1–1.5, p = .007]. Use of hormonal therapy and smoking also increased opioid use risk [OR = 6.16, 95% CI 1.7–22.5, p = 0.006, OR = 4.36, 95% CI 1.2–16.1, p = .027, respectively]. Within the opioid users group, all pain symptoms and quality of life domains were significantly improved, with the most significant improvement demonstrated in dysmenorrhea and sleeping quality (median change: -4.5 (p < .001) and 5 (p < .001) points, respectively). While there were no life-threatening side effects, 94% of women using opioids experienced at least one side effect and 33% had moderate to high risk of addiction. In our study, the risk of opioid use among women with endometriosis was increased for women with hormonal therapy, smoking and higher pain severity. While opioids were associated with high rates of side effects, they were effective pain relievers and overall quality of life was improved. More research is needed to delineate better the role and risks of opioids for the treatment of endometriosis associated pain.