High Incidence of Abnormal Circadian Blood Pressure Profiles in Patients on Steroid Replacement Therapy due to Secondary Adrenal Insufficiencyand Congenital Adrenal Hyperplasia without Overt Hypertension - InitialResults

Abstract

Patients on steroid replacement therapy are at an increased risk of cardiovascular complications owing to the fact that disruptions in the cortisol diurnal rhythm may affect the blood pressure (BP) profile. Aim: To evaluate the circadian BP profiles of patients with secondary adrenal insufficiency (SAI) and congenital adrenal hyperplasia (CAH) on steroid replacement therapy and to compare BP profiles of patients receiving hydrocortisone (HC) in different dosing schedules. Methods: The study included 33 patients: 15 SAI and 18 CAH (mean age 13.2 years 95CI 11.3-15.1). There were no patients with previously diagnosed overt hypertension. Patients with SAI received a mean of 7.39 mg/m2 of HC in 3 daily doses (in the morning (M) 50%, in the afternoon (A) 25%, in the evening (E) 25%), CAH patients 17.9 mg/m2 of HC in the following dosing schedules: 5 patients in 3 equal doses, 7 patients received M: 40% A: 40% E: 20%, the remaining 6 patients had the same dosing schedule as patients with SAI. Fludrocortisone (FC) was given to 13 patients with CAH in 2 equal daily doses. The total dose of HC/FC as well as the dosing schedule of HC was adjusted individually based on clinical and biochemical outcomes. Standard 24-hour BP monitoring (ABPM) was performed using an Ambulatory BP Monitor (Space labs 90217, USA). Results: The majority of the patients (almost 70% SAI, 80% CAH) presented with an abnormal 24-hour BP profile. There were no significant differences in ABPM results between SAI and CAH patients, and no differences between CAH patients treated with and without FC. There was no correlation between HC and FC doses [mg/m2] and ABPM results except that mean night SBP values increased with greater HC doses (r=0.51, p<0.05). Among the CAH group the highest percentage of abnormal ABPM results was observed in patients who received HC in doses: M: 50% A: 25% and E: 25%, the most favorable BP profile was observed in patients with dosing schedule: M: 40%, A: 40%, E: 20%.However there were no significant differences between patients with different treatment protocols, the results suggest that observed disruptions of the BP profile could be related to the HC dosing schedule. Conclusions: The incidence of abnormal BP profiles in patients on steroid replacement therapy due to SAI and CAH without overt hypertension is high. The disruptions of the BP profiles are not associated with the dose of HC or FC. The abnormal BP profiles in patients with SAI or CAH may be related to the HC dosing schedule. 24-hour ABPM seems to be a useful, non-invasive and safe method for the monitoring of HC and FC replacement therapy in patients with adrenal insufficiency. Further investigations in the larger groups of patients are needed.