Rheumatoid Arthritis Adrenal Recovery Study

Cortisol is a naturally occurring stress hormone, made by the adrenal glands in response to hormones produced by the pituitary and hypothalamus. Man-made forms of cortisol ('steroids', for example prednisolone) have been used for the treatment of rheumatoid arthritis since the 1950s; they are very effective at reducing inflammation. A normal response to taking steroid treatment is that the body needs to make less cortisol. Following treatment with steroids, the system responsible for making cortisol can be slow to wake up. If someone does not make enough cortisol, they are less able to deal with stress and are at increased risk of becoming unwell, or suffering a potentially fatal adrenal crisis. It is not clear how common failure of recovery of the adrenal axis is, how long it can last for or, if any factors might predict which patients are most at risk. This study aims to improve our understanding of hypothalamus-pituitary-adrenal (HPA) axis recovery in patients with rheumatoid arthritis treated with prednisolone. The investigators will also test potential predictive biomarkers of recovery. The study will be conducted in hospital and a clinical research facility. Participants will undergo two visits for blood tests and will also be asked to supply three samples of saliva on six days over the three weeks of the study. A better understanding of the physiology of HPA axis recovery should inform the development of tools which would allow prediction of patients at risk following withdrawal of steroid treatment. Such tools would be useful to improve patient safety.