Endocrine Abstracts

Background: Management of adrenal insufficiency (AI) with glucocorticoid replacement is associated with increased mortality and morbidity. There is growing evidence that this is because of excess, non-physiological steroid exposure. Low dose prednisolone (2-4 mg) is a once-daily alternative to standard hydrocortisone regimens that more closely mimics the circadian rhythm and may translate to better outcomes. There is however a paucity of studies comparing the two treatments.

Methods: Twenty healthy volunteers (HV), 20 AI patients on prednisolone, 18 AI patients on hydrocortisone and 5 patients on anti-inflammatory doses of steroids (including IV methyl-prednisolone) were recruited to this study. All groups had anthropometric, bone turnover, glycaemic, immune cell and cardiovascular risk markers assessed at a single timepoint. Patient groups had blood samples collected 2 hours after steroid treatment was administered.

Results: Mean hydrocortisone dose was 29.0 mg compared to 3.3 mg of prednisolone. Hydrocortisone patients had larger waist-hip ratios than HVs (0.9 vs 0.83; P < 0.05). No other differences in anthropometric markers were noted. Urinary NTX was significantly elevated in the anti-inflammatory group compared to the prednisolone and hydrocortisone groups. Triglycerides were markedly elevated in the hydrocortisone patients compared to HVs (1.28 mmol/l vs 0.86 mmol/l; P < 0.05). WBC was significantly elevated in the hydrocortisone and anti-inflammatory groups compared to the healthy volunteers, but not in the prednisolone group. All treatment groups demonstrated a raised neutrophil count compared to the healthy volunteers. Fructosamine was significantly higher than the HVs in the hydrocortisone group but HOMA-B was significantly lower.

Conclusions: There are currently no clear differences between prednisolone and hydrocortisone in the management of AI. There are some indications that hydrocortisone may be worse for cardiovascular risk, and glycaemic outcomes, but the data for the latter is discordant. All treatment groups showed a neutrophilia compared to HVs, suggesting that there remain relative excess glucocorticoid exposure.