Mild cognitive deficits in patients with primary adrenal insufficiency

The brain is a major target organ for cortisol considering its high density of glucocorticoid receptors. Several states of hypothalamus-pituitary-adrenal dysregulation point towards impairments in cognitive functioning. However, there is a very limited body of research on the effects of hypocortisolism on cognitive functioning.

To evaluate cognitive functioning in patients with hypocortisolism (i.e., primary adrenal insufficiency (PAI)) and to examine the possible effect of postponing early-morning hydrocortisone intake on cognitive functioning.

Thirty-one patients with PAI on regular morning hydrocortisone intake and 31 healthy matched controls underwent nine neuropsychological tests, evaluating memory and executive functioning. In addition, the effect of normal timing and postponement of morning hydrocortisone intake on neuropsychological tests were assessed in an additional 29 patients with PAI.

Compared to controls, patients with PAI performed worse on auditory and visual memory tasks (all P ≤ 0.024) and executive functioning tasks (all P ≤ 0.012). In contrast, patients performed better on a concentration and an attention task (both P<0.05). Postponement of hydrocortisone intake in the morning did not affect the outcomes of neuropsychological tests.

Patients on long-term hydrocortisone replacement for PAI show mild cognitive deficits compared to controls. There was no effect of postponement of regular hydrocortisone intake on cognition.