Influence of Frailty Status on the Efficacy of Epidural Steroid Injections in Elderly Patients With Degenerative Lumbar Spinal Disease

Abstract

Background: The global increase in the elderly population has led to a higher prevalence of degenerative lumbar spinal diseases. Epidural steroid injection (ESI) is a widely used procedure for managing lower back pain. This study investigated the association of preprocedural frailty status with the efficacy of ESI in elderly patients diagnosed with degenerative lumbar spinal diseases. Methods: This retrospective observational study included patients aged 65 years and older who underwent lumbar ESI. Frailty status (robust, prefrail, and frail) assessed via the Frailty Phenotype Questionnaire was collected along with demographic and clinical parameters. Good analgesia was defined as a ≥ 50% reduction in pain score at 4-week follow-up evaluation. Multivariable logistic regression analyses were performed to identify factors associated with poor analgesia. Results: We included 289 patients in this study. Frailty status correlated with analgesic outcomes, with worsening frailty status correlating with increasingly poor analgesia after the injection (robust = 34.5%, prefrail = 40.8%, and frail = 60.0%, p=0.003), predominantly in female patients. After adjusting for demographic and clinical factors, frail patients demonstrated much higher odds of poor analgesia than robust individuals (adjusted odds ratio [aOR] = 2.673, 95% confidence interval [CI] = 1.338-5.342, p=0.005). Conversely, prefrail patients did not show a significant association with analgesic outcome (aOR = 1.293, 95% CI = 0.736-2.272, p=0.372). Conclusions: Frailty, but not prefrailty, appeared to be an independent factor associated with poor analgesic efficacy of ESI in elderly patients with symptomatic degenerative lumbar spinal disease receiving conservative care.