Endocrine Abstracts

Background: Individuals with adrenal insufficiency (AI) receive life-long glucocorticoid (GC) replacement which often exceeds physiological daily GC production, with negative effects on cardiometabolic and bone health parameters.

Objective: Assessment of cardiometabolic and bone health markers in postmenopausal females with AI in relation to the GC dose.

Methods: We retrospectively collected 114 postmenopausal women with AI (37 with primary AI [PAI], 37 with secondary AI [SAI] and 40 with AI following Cushing’s syndrome (CS) treatment [post-CS AI]). HbA1c, lipid, bone markers and bone mineral density (BMD) in lumbar spine (LS) and femoral neck (FN) were evaluated at baseline and after 2 years. Total daily hydrocortisone (TDHC) doses were considered as: low dose (LD; TDHC≤15 mg, 21 patients), medium dose (MD; 15 mg<TDHC≤25 mg, 50 patients) and high dose (HD; TDHC>25 mg, 43 patients)

Results: Patients were comparable for age, duration of AI, age of menopause and BMI. More PAI patients were on LD (24% vs 14% and 18% for SAI and post-CS, respectively) and more post-CS AI on HD (45% vs 30% and 38% for PAI and SAI, respectively). TDHC did not differ among groups, but PAI patients received less GC/body surface area (BSA). No statistically significant differences were observed in BMD and LS or FN T-Scores but PAI patients had higher P1NP levels. They also had lower HbA1c, cholesterol and LDL values compared to the other 2 groups. After 2 years, BMD and T-Scores remained comparable for the 3 groups. P1NP values remained higher in PAI patients who also continued to exhibit lower lipid levels compared to the SAI and post-CS AI ones.

Conclusions: PAI patients had increased bone formation and better HbA1c and lipid levels compared to SAI and post-CS patients, at baseline and after two years. This possibly relates to the use of lower GC/BSA doses in PAI patients due to residual adrenal function. Of note, when only the mean TDHC was considered no difference was evident, indicating that a BSA based GC dose calculation may better reflect an individual’s exposure to GCs. Although lower GC doses are recommended, many AI patients, especially post-CS, cannot tolerate doses of <25 mg/day. Our data enforce the need for the lowest possible GC replacement dose in AI patients, however tolerability may hamper this effort, especially in SAI and in post-CS patients.