Effects of Steroid Replacement Therapy on Metabolic, Cardiovascular and Bone Outcomes in Adrenal Insufficiency

Adrenal insufficiency (AI) can be caused by a disease involving the adrenal gland resulting in inadequate secretion of adrenal cortex hormones, primary adrenal insufficiency (PAI). Secondary adrenal insufficiency (SAI) results from a decreased level of adrenocorticotrophin hormone (ACTH) released from the pituitary gland. The mainstay of treatment of PAI and SAI is glucocorticoid (GC) replacement therapy. Conventional steroid replacement therapy includes cortisone acetate and hydrocortisone administered 2-3 times a day with the highest dose in the morning and the lowest dose in the afternoon. These dosing regimens have been designed to mimic the peak of cortisol secretion in the morning and avoid overdosing during the night hours, even though a higher risk of developing comorbidities has been shown, notably in patients treated with higher evening doses. In patients with AI on conventional steroid replacement therapy, mortality remains higher than in the general population, mainly due to non-physiological daily GC overexposure and to inadequate cortisol exposure during stress-related events and illness. Studies aiming to evaluate the long-term clinical outcomes of patients with AI on conventional steroid replacement therapy clearly showed increased comorbidities, mainly related to the dose used. By contrast, dual-release hydrocortisone (DR-HC) is characterized by once-daily administration with high release of hydrocortisone immediately after intake and a very low release in the evening and nocturnal hours. The switch from conventional GC therapy to DR-HC has been shown to be associated with improvement in BMI, hepatic, bone and glucometabolic parameters and QoL. However, long-term clinical outcomes of patients treated with DR-HC in patients naïve to steroid treatment are not known.