Impaired adrenal reserve in men with spinal cord injury: results of low- and high-dose adrenocorticotropin stimulation tests.

Abstract

To use low- and high-dose adrenocorticotropin (ACTH) tests to assess adrenal reserve in men with spinal cord injury (SCI). After an overnight fast, 1 microg and 200 microg ACTH were injected intravenously at time 0 and 60 minutes between 8 AM and 9 AM. Blood was withdrawn at 30-minute intervals from time 0 to 120 minutes. All participants were recruited from the outpatient clinic of a university hospital that is a tertiary referral center. Forty-two men with traumatic neurologically complete SCI that had occurred more than 1 year before the study. Serum cortisol response to ACTH at times 0, 30, 60, 90, and 120 minutes. Twenty subjects had a serum cortisol response of <20 microg/dL 30 minutes after a 1-microg ACTH injection; 10 of these remained at this level at 30 minutes after a 200-microg ACTH injection. There is a high prevalence of impaired adrenal reserve in persons with chronic SCI. The 1-microg (low dose) ACTH test is more sensitive for detecting subclinical adrenal insufficiency than is the 200-microg (high dose) ACTH test.