Cognitive function in Hashimoto's thyroiditis under levothyroxine treatment.

UNLABELLED: ΟBJECTIVE: Although overt hypothyroidism has been documented as exerting detrimental effects on cognition and behavior, it remains controversial whether subclinical hypothyroidism or euthyroid patients with Hashimoto's thyroiditis (HT) under levothyroxine (LT4) treatment may experience any noticeable decline in cognitive function.

PATIENTS: Two otherwise healthy, highly-functioning, first-degree relatives with a diagnosis of HT, under LT4 treatment for two years, were prospectively recruited into a clinical research study setting and followed for a year.

MEASUREMENTS: Thyroid functions tests and a detailed battery of tests assessing global cognitive status, attention, verbal and working memory, visuoperceptual skills, executive functions and mood were performed at baseline and at one year after recruitment.

RESULTS: Overall, patients' performance on the neuropsychological battery was good and, in the majority of cognitive functions, their performance could be characterized as exceptional. No noticeable changes in any of the studied parameters were detected.

CONCLUSIONS: The present case study failed to detect any noticeable changes in the cognitive and emotional function of two women with HT under LT4 treatment. The course of cognitive function of the two HT patients, evaluated by a detailed battery of tests, tends to confirm the benign nature of HT.