Cognitive impairment and magnetic resonance imaging correlations in Wilson's disease

To evaluate the cognitive performance of a group of patients with Wilson's disease (WD) and to correlate the cognitive findings with changes in magnetic resonance imaging (MRI).

All patients with WD consecutively attended in a Movement Disorders Clinic between September 2006 and October 2007 were invited to participate in the study, together with a group of matched healthy controls. Patients and controls were submitted to comprehensive neuropsychological assessment. MRI was performed in all patients, and abnormalities (high-intensity signal, low-intensity signal and atrophy) were semi-quantitatively rated. Performance of patients and controls in each cognitive test was compared, and correlations between cognitive scores and MRI changes were investigated within the patients' group.

Twenty patients with WD (11 men) and 20 controls (nine men) were evaluated. Mean age in the WD and control groups was 30.05 ± 7.25 and 32.15 ± 5.37 years, respectively. Mean schooling years were 11.15 ± 3.73 among WD cases and 10.08 ± 2.62 among controls. Patients with WD performed significantly worse than controls in the Mini-Mental State Examination, Dementia Rating Scale, phonemic verbal fluency (FAS), verb generation, digit span forward, Stroop test, Frontal Assessment Battery and in the Brief Cognitive Screening Battery. A significant correlation emerged between global cognitive impairment and MRI scale (r = 0.535), being higher for high-intensity signal plus atrophy (r = 0.718).

Patients with WD presented cognitive impairment, especially in executive functions, with good correlation between cognitive abnormalities and MRI changes.