SAT0159 Inhibition of Adrenal Axis in Elderly Patients under Treatment with Low Dosis of Corticosteroids: Should We Supplement in Stressful Situations?

Background In some rheumatic diseases low dosis of glucocorticoids (2-5 mg) are used for long periods of time. It is not clear if there is an inhibition of the adrenal axis when one of these patients experiences a stressful situation, such as an illness. This is particularly important in elderly patients, who are most vulnerable to hospitalization. Objectives Determine whether there is inhibition of adrenal axis in elderly patients under treatment with low dosis of corticosteroids. Methods Design: prospective. Type of center: University hospital with a referral area of 850,000 inhabitants. Nineteen patients with inflammatory rheumatic diseases (Elderly Onset Rheumatoid Arthritis and Polymyalgia Rheumatica) were studied: 7 women and 12 men, with a mean age of 77±6.84 years. We underwent stimulation test with synthetic ACTH 1 μg before the onset of oral glucocorticoid treatment and 6 months later. Methylprednisolone was the glucocorticoid used in all patients. The starting mean dose used is these patients was 9.26±2.68 mg, the dose accumulated in 6 months 972.6±248 mg, and the mean daily dose of 5.22±1.0 mg/day. Statistical methods: student t test, ANOVA and ROC curve. Results A good response was observed in all patients before before the onset of oral glucocorticoids (cortisol at 30 minutes ≥18 mg/dl). After 6 months of treatment the basal cortisol decreased from 18.5±5.9 to 11.95±5.9 (p=0.002) and the stimulated one from 28.96±5.8 to 17.95±5.98 (p Patients with an inadequate response had received a higher starting dose of glucocorticoids (8±2.8 versus 10.4±2.0, p=0.048) and also a higher mean daily dose (4.6±1.05 versus 5.7±0.7, p=0.018). Moreover, the accumulated dose and the mean daily dose were inversely correlated with the cortisol response. The ROC curve analysis at 6 months of treatment showed that the best cut off for predicting a poor response was a mean daily dose of 5.16 mg/day, with 70% sensitivity and 88.89% specificity (AUC =0.789, p=0.0065) and that a 100% of patients with insufficient response received a mean daily dose higher than 4.5mg/day. Conclusions A large percentage of elderly patients treated with low dosis of glucocorticoids showed adrenal axis inhibition after a few months of treatment. Thus, supplementation with higher dosis of glucocorticoids should be recommended to these patients in stressful situations. Acknowledgements To all the Biochemistry and Reumathology nurses. Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.4520