Endocrine Abstracts

Background: Patients with adrenal insufficiency (AI) require glucocorticoid replacement therapy. Current Endocrine Society guidelines recommend thrice-daily hydrocortisone (15-25mg) or once-daily prednisolone (3-5mg). Concerns around prednisolone use have been based on evidence using higher doses. We have been using low-dose (2-4mg) once-daily prednisolone since 2014 for glucocorticoid replacement in adult patients with AI. This study aimed to compare the effects of each glucocorticoid on the risk of cardiovascular disease and adrenal crises.

Methodology: A cohort of adult patients with AI at Imperial College Healthcare NHS Trust (n=100), initially studied in a 2017 audit, were re-audited in 2021. Data on anthropometric and biochemical markers of cardiovascular risk, including body mass index (BMI), blood pressure, lipid profiles, and HbA1c, were obtained from the most recent electronic medical records since May 2019 (2-4 years from initial data collection). Adrenal crises occurring since May 2017 were also recorded.

Results: 58 patients were taking hydrocortisone (mean total daily dose of 18.7 ± 5.0mg) and 42 were taking prednisolone (mean daily dose of 3.26 ± 1.16mg). There were no significant changes in markers of cardiovascular risk in patients who remained on prednisolone between 2017-2021 (n=32), nor in patients who switched from prednisolone to hydrocortisone (n=5). In patients who remained on hydrocortisone (n=54), HbA1c and random glucose were significantly higher in 2021 than 2017. In patients who switched from hydrocortisone to prednisolone between 2017-2021 (n=9), weight and BMI were significantly lower on prednisolone (mean weight difference -5.4 kg, P=0.04). One adrenal crisis occurred on hydrocortisone compared to none on prednisolone.

Conclusion: Once daily low-dose prednisolone is safe for the treatment of AI and may have a beneficial effect on weight in patients switched from hydrocortisone. Further clinical studies are actively recruiting to determine the optimal glucocorticoid replacement therapy for AI (The HYPER-AID Study (NCT03608943)).