The Effects of Epidural Betamethasone on Blood Glucose in Patients with Diabetes Mellitus

Objective: To determine the effects of lumbosacral transforaminal and caudal epidural betamethasone injections on blood glucose levels in diabetic subjects. The hypothesis is that epidural steroid injections result in transient elevation of blood glucose levels in diabetic subjects. Design: This is a prospective, observational cohort. Twelve diabetic subjects (6 non insulin-dependent and 6 insulin-dependent) receiving lumbosacral or caudal epidural betamethasone injections for neurogenic claudication or radicular pain were studied. Spinal level and approach were decided based on symptoms, pathology, and magnetic resonance imaging findings. Subjects recorded their finger stick blood glucose levels twice daily for 3 days before the injection, the day of the injection, and 3 days after the injection. Setting: A tertiary, university-based, spine center. Participants: Inclusion criteria included diabetic subjects (age 18 years) with the ability and willingness to monitor and report their blood glucose. Exclusion criteria included epidural steroid injections (ESIs) within the previous 2 months or peripheral corticosteroid injections within the previous 2 weeks. Nineteen subjects initially enrolled, and 12 successfully completed the study. Interventions: After informed consent was obtained, subjects underwent fluoroscopically guided lumbosacral transforaminal ESIs (TFESIs) or caudal ESIs, using contrast to confirm targeted needle placement and to rule out vascular uptake. Main Outcome Measures: Subjects recorded morning and evening blood glucose (mg/dL) via glucometer. Results: There was a 106 mg/dL average elevation in blood glucose level on the evening of the injection day. The blood glucose elevation remained statistically significant for 3 days after the injection (P<.002). Blood glucose remained elevated through postinjection day 2, though these elevations were not statistically significant. Conclusions: Lumbosacral transforaminal and caudal epidural betamethasone injections are associated with statistically significant elevations in blood glucose levels in diabetic subjects. This effect peaked on the day of the injection and lasted approximately 2 days.