Cognitive deficits in multiple sclerosis patients with cerebellar symptoms

Abstract

Background Cerebellar dysfunction is common in patients with multiple sclerosis (MS). However, neuropsychological studies of this clinical feature are lacking. Objective We investigate the neuropsychological features in relapsing-remitting MS (RR-MS) patients with and without cerebellar dysfunction. Methods Twenty-one RR-MS patients with cerebellar dysfunction (RR-MSc), characterized by prevalent ataxic gait and nystagmus, and 21 RR-MS patients without any cerebellar manifestation (RR-MSnc) pair-matched for demographical and clinical variables were studied. All patients from each group underwent an extensive battery of neuropsychological tests. Magnetic resonance imaging analysis included hyperintense fast fluid-attenuated inversion-recovery lesion load in the whole brain as well as in the four lobes separately. Results Any significant differences were detected in total and regional lesion load measurements between the two groups. RR-MSc group performed equally as well as the RR-MSnc group on many of the cognitive exploration measures. Nevertheless, the RR-MSc group performed more poorly than the RR-MSnc group on attention tests (Symbol Digit Modalities Test) and verbal fluency tests (Controlled Oral Word Association Test); neither of the test results proved to be affected by regional lesion loads. Conclusion These results highlight the importance of considering cognitive deficits associated with the presence of cerebellar symptoms in RR-MS.