Hydrocortisone Versus Prednisolone for the Treatment of Adrenal Insufficiency Disease (HYPER-AID)

There are over 27,000 individuals in the United Kingdom with Adrenal Insufficiency (AI), a condition in which the body is unable to produce sufficient amounts of steroid hormones. Steroid hormones like cortisol are needed for normal bodily function and are especially important at times of stress. The absence of cortisol causes symptoms including nausea, lethargy and can lead to fatal emergencies called adrenal crises. This condition is treated by replacing the insufficient hormone using oral tablets. The majority of patients in the UK are managed using hydrocortisone or prednisolone. Hydrocortisone is expensive and has a short duration of action, necessitating three doses per day. Prednisolone is much cheaper, and has a longer duration of action meaning that it is taken once per day. At present there is no evidence in favour of either drug. This study will investigate the effects of both medications on bone health, cardiovascular risk, blood glucose control and well-being, in patients with AI. There are two parts to this study, Part A and Part B. Part A will be a retrospective observational study in which members of the routine clinical care team will audit the notes and biochemical records of patients who have previously been switched between hydrocortisone and prednisolone as part of their standard care. Part B will take patients who have received a stable regimen of either therapy for at least 4 months and will prospectively recruit them to this study as they change to the alternative therapy as part of their routine clinical care. We will compare biological measurements (such as blood pressure, pulse, hip and waist size), blood test results, urine test results and questionnaire responses before and 4 months after patients change their therapy. All investigations, measurements and questionnaires are part of routine clinical care, and no additional study specific tests will be performed.