Hypothalamic-pituitary-adrenal function in extrinsic asthma.

Hypothalamic-pituitary-adrenal function in a well-defined, carefully selected group of 25 patients with extrinsic asthma was assessed by measuring plasma levels of adrenocorticotropic hormone (ACTH) and of 11-deoxycorticol after administration of metyrapone and by measuring the level of cortisol following stimulation with cosyntropin. No difference was demonstrated between asthmatic subjects and 20 normal age-matched controls. In addition, neither the response of the level of ACTH nor of 11-deoxycortisol correlated with the duration of asthma or the severity as assessed in 23 patients by tests of pulmonary function. We conclude that there is no abnormality in hypothalamic-pituitary-adrenal function in patients with extrinsic asthma, and we suggest that previous data suggesting such an abnormality may reflect heterogeneous groups of patients, inaccurate methods, and the variability of normal responses to ACTH and stimulation with metyrapone.