Prevalence of Opioid-Induced Adrenal Insufficiency in Patients Taking Chronic Opioids.

CONTEXT: Chronic opioid use may lead to adrenal insufficiency because of central suppression of the hypothalamic-pituitary-adrenal axis. However, the prevalence of opioid-induced adrenal insufficiency (OIAI) is unclear. OBJECTIVE: To determine the prevalence of OIAI and to identify predictors for the development of OIAI in patients taking opioids for chronic pain. DESIGN: Cross-sectional study, 2016-2018. SETTING: Referral center. PATIENTS: Adult patients taking chronic opioids admitted to the Pain Rehabilitation Center. MAIN OUTCOME MEASURE: Diagnosis of OIAI was considered if positive case detection (cortisol†<†10 mcg/dL, ACTH†<†15 pg/mL, and dehydroepiandrosterone sulfate†<†25 mcg/dL), and confirmed after endocrine evaluation. Daily morphine milligram equivalent (MME) was calculated. RESULTS: In 102 patients (median age, 53 years [range, 22-83], 67% women), median daily MME was 60 mg (3-840), and median opioid therapy duration was 60 months (3-360). Abnormal case detection testing was found in 11 (10.8%) patients, and diagnosis of OIAI was made in 9 (9%). Patients with OIAI were on a higher daily MME (median, 140 [20-392] mg vs 57 [3-840] mg, P†=†0.1), and demonstrated a 4 times higher cumulative opioid exposure (median of 13,440 vs 3120 mg*months, P†=†0.03). No patient taking †20 mg); however, specificity of MME cutoff >20 mg was only 19%. After opioid discontinuation, 6/7 patients recovered adrenal function. CONCLUSION: The prevalence of OIAI was 9%, with MME cumulative exposure being the only predictor for OIAI development. Patients on MME of 20 mg/day and above should be monitored for OIAI.