Cognitive function in patients with Cushing syndrome: a longitudinal perspective.

The purposes of this study were to examine the level of improvement of cognitive function 12 months posttreatment in adult patients with Cushing syndrome (CS), the relationships of cognitive function to duration of CS or recovery of the hypothalamic pituitary adrenal (HPA) axis, and depression and improved cognitive functioning. Thirty-three patients with CS and a matched comparison group were enrolled. IQ, depression, and endocrine factors were measured during the active phase of CS and at 12 months posttreatment for CS. Results show no group differences in cognitive function across time but a trend for CS patients to have lower IQ scores at baseline. Individual differences in performance were striking. For some subscales of IQ there was a positive relationship with recovery of the HPA axis and a negative relationship with duration of CS as well as an improvement if depression had decreased. Limitations of the study are cited along with clinical implications and directions for future research.