Neuropsychiatric Side Effects After Lumbosacral Epidural Steroid Injections: A Prospective Cohort Study.

BACKGROUND: The central nervous system contains steroid receptors, particularly in the hypothalamic and limbic systems. These systems are responsible for driving certain emotions in humans, especially stress, anxiety, motivation, energy levels, and mood. Thus, corticosteroids may precipitate patients to experience these emotions. Most existing studies report neuropsychiatric side effects after oral or intravenous corticosteroids rather than epidural.

OBJECTIVES: This study examines the neuropsychiatric side effects after epidural steroid injections (ESIs), with a focus on whether certain factors in patients' histories further exacerbate symptomatology.

STUDY DESIGN: Prospective observational cohort study.

SETTING: Fluoroscopy suite at an urban academic teaching hospital.

METHODS: Patients were called 24 hours and one week after their ESIs and asked if they experienced certain neuropsychiatric symptoms more than usual compared to baseline.

PATIENTS: Seventy-four patients undergoing a lumbosacral ESI (interlaminar (ILESI), caudal or transforaminal (TFESI)) were invited to take part in the study the day of his or her procedure.

INTERVENTION/MEASUREMENT: Assessed whether psychiatric history, gender, race, type of ESI, or the number of levels injected affected frequency and duration of neuropsychiatric symptoms at one day and one week after an ESI.

RESULTS: Significantly (P < 0.05) more patients with a psychiatric history experienced restlessness and irritability at day one than those without a psychiatric history. At week one, male gender (IRR 2.29, 95% CI 1.37, 3.83, P = 0.002), ILESI (IRR 7.75, 95% CI 1.03, 58.6, P = 0.047), and 2-level injections (IRR 2.14, 95% CI 1.13, 4.06, P = 0.019) were significantly associated to more total symptoms.

LIMITATIONS: Single center study, reliance on subjective responses from patients, lack of follow-up after one week post-ESI.

CONCLUSION(S): This study demonstrates that neuropsychiatric symptoms are rare overall after an ESI, though certain factors may influence patients experiencing these symptoms. Restlessness and irritability were more likely to occur one day after an ESI in those with a psychiatric history. Those who had a 2-level injection were more likely to keep experiencing most symptoms by week one, suggesting a possible correlation between corticosteroid dose and neuropsychiatric symptoms.