Context: Conventional glucocorticoid replacement therapy fails to mimic the physiological cortisol rhythm, which may have implications for morbidity and mortality in patients with Addison's disease.
Objective: The objective of the study was to compare the effects of continuous sc hydrocortisone infusion (CSHI) with conventional oral hydrocortisone (OHC) replacement therapy.
Design, patients, and interventions: This was a prospective crossover, randomized, multicenter clinical trial comparing 3 months of treatment with thrice-daily OHC vs CSHI. From Norway and Sweden, 33 patients were enrolled from registries and clinics. All patients were assessed at baseline and after 8 and 12 weeks in each treatment arm.
Main outcome measures: The morning ACTH level was the primary outcome measure. Secondary outcome measures were effects on metabolism, health-related quality of life (HRQoL), sleep, and safety.
Results: CSHI yielded normalization of morning ACTH and cortisol levels, and 24-hour salivary cortisol curves resembled the normal circadian variation. Urinary concentrations of glucocorticoid metabolites displayed a normal pattern with CSHI but were clearly altered with OHC. Several HRQoL indices in the vitality domain improved over time with CSHI. No benefit was found for either treatments for any subjective (Pittsburgh Sleep Quality Index questionnaire) or objective (actigraphy) sleep parameters.
Conclusion: CSHI safely brought ACTH and cortisol toward normal circadian levels without adversely affecting glucocorticoid metabolism in the way that OHC did. Positive effects on HRQoL were noted with CSHI, indicating that physiological glucocorticoid replacement therapy may be beneficial and that CSHI might become a treatment option for patients poorly controlled on conventional therapy.