Cognitive impairment in adolescents and adults with congenital adrenal hyperplasia.

Objective: Impaired cognition has been reported in patients with congenital adrenal hyperplasia (CAH), although the findings have been conflicting. It has been hypothesized that the major causes of the deficits are prenatal hormonal imbalances and/or excessive glucocorticoid treatment.

Design: An observational study investigating cognition in patients with CAH.

Patients: A total of 55 patients with CAH and 58 control subjects from the general population, aged 16-33 years. Nine CAH subjects had been treated prenatally with dexamethasone.

Setting: Singel research institute.

Measurements: Standardized neuropsychological tests (Wechsler Scales and Stroop Interference Test) and questionnaires (Barkley Deficit in Executive Functioning Scale) were used.

Results: Compared to controls, patients with CAH had impaired performance in tests measuring verbal working memory (P = .024), visual-spatial working memory (P = .005 and P = .003) and inhibition (P = .002). In measures of fluid intelligence/nonverbal logical reasoning, males with CAH performed poorer than control males (P = .033). Patients with salt-wasting CAH performed equally compared to patients with simple virilizing CAH. However, patients with a null genotype performed poorer than patients with a non-null genotype and significantly worse on fluid intelligence/nonverbal logical reasoning (P = .042). Prenatally-treated women performed worse on most cognitive measures than women with CAH not treated prenatally.

Conclusions: Patients with CAH had normal psychometric intelligence but impaired executive functions compared with population controls. A null CAH genotype was associated with poorer general cognitive capacity.