Patient gender and opioid administration in the emergency department for acute low back pain: a retrospective study in 17 French emergency departments

Background and importance Low back pain (LBP) is a common reason for emergency department (ED) visits, but its management remains variable across sites and providers. Opioid use for acute LBP is controversial, and possible gender-related disparities in prescribing practices have been reported in other clinical settings. Understanding whether such disparities exist in ED care is important for ensuring equitable treatment. Objective We aimed to determine whether patient gender influences the likelihood of opioid administration in the ED for acute LBP. Design Multicenter retrospective observational cohort study. Settings and participants Seventeen French EDs participated. Adults aged 20–55 years presenting between 1 January and 1 July 2024, with acute mechanical LBP of less than 6 weeks’ duration and without clinical red flags were included. Exposure The exposure of interest was patient gender. Pain severity was assessed at triage using the Numeric Rating Scale (NRS). Outcome measures and analysis The primary outcome was opioid administration in the ED. Opioid use was first compared between men and women across pain severity categories (mild: NRS 1–3, moderate: 4–6, severe: 7–10). Multivariable logistic regression adjusted for initial NRS was then performed, and sensitivity analyses using multiple imputation addressed missing NRS values. Main results A total of 558 patients were included, of whom 236 (42.3%) were women. The median initial NRS was 5.0 [interquartile range (IQR): 3–7]; 61 patients (10.9%) had missing NRS values. Overall, opioids were administered in 43.9% of visits (codeine 12.7%, tramadol 14.9%, and morphine 19.4%). No significant gender differences were observed across pain categories: mild [20.6 vs. 17.9%; odds ratio (OR): 1.19, 95% confidence interval (CI): 0.40–3.39], moderate (50.7 vs. 42.0%; OR: 1.42, 95% CI: 0.78–2.58), and severe (73.3 vs. 72.3%; OR: 1.05, 95% CI: 0.52–2.10). In multivariable analysis, gender was not associated with either opioid use (OR: 1.16, 95% CI: 0.77–1.75) or morphine use (OR: 1.14, 95% CI: 0.69–1.89). Sensitivity analyses yielded similar findings. Conclusion In this multicenter retrospective study, gender did not significantly influence opioid or morphine administration in patients presenting with acute low back pain in the ED.