Patients with adrenal insufficiency have cardiovascular features associated with hypovolemia

CONTEXT: Patients with adrenal insufficiency (AI) have excess mortality and morbidity, mainly due to cardiovascular (CV) diseases. The mechanisms for this is unclear. OBJECTIVE: To assess CV structure and function in AI patients on conventional replacement therapy and after switching to once-daily, modified-release hydrocortisone (OD-HC) in comparison with healthy matched controls. METHODS: This was a retrospective analysis of 17 adult AI patients (11 with primary AI, 6 with secondary AI) on stable replacement with cortisone acetate [median (minimum, maximum) 33.5 (12.5–50) mg] and, if needed, fludrocortisone [0.1 (0.05–0.2) mg], and 17 healthy matched controls. Ten patients were switched to an equivalent dose of OD-HC. Data from echocardiography, 24 h Holter-ECG and 24 h blood pressure monitoring were collected at baseline and 6 months after the switch to OD-HC. RESULTS: At baseline, AI patients had smaller left ventricular diastolic diameter (47.1 ± 4.2 vs. 51.6 ± 2.3 mm; P = 0.001) and left atrial diameter (34.9 ± 4.7 vs. 38.2 ± 2.6 cm; P = 0.018), and a higher ejection fraction (62.5 ± 6.9% vs. 56.0 ± 4.7%; P = 0.003) than controls. AI patients had lower nocturnal systolic and diastolic blood pressure than controls (108 ± 15 mmHg vs. 117 ± 8 mmHg; P = 0.038 and 65 ± 9 mmHg vs. 73 ± 7 mmHg; P = 0.008, respectively). After the switch to OD-HC, nocturnal diastolic blood pressure normalised. No significant changes were observed in echocardiographic and Holter-ECG parameters following the switch. CONCLUSIONS: AI patients on conventional treatment display cardiovascular abnormalities that could be related to hypovolemia. Switch to OD-HC seems to have beneficial effect on blood pressure profile, but no effect on cardiovascular structure and function.