Affiliations: Univ Paris Diderot, Sorbonne Paris Cité, UMR 1161 INSERM, F-75205 Paris, France and AP-HP, Lariboisière Hosp, Department of Neurology, F-75475 Paris, France and DHU Neurovasc Paris Sorbonne, Paris, France
Correspondence:
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Correspondence to: Pr Hugues Chabriat, Service de Neuro-logie, Hôpital Lariboisière, 2 rue Ambroise Paré, 75010 Paris, France. Tel.: +33 1 49 95 65 09; Fax: +33 1 49 95 25 96; [email protected]
Abstract:
Background: The assessment of early and subtle cognitive and behavioral effects of cerebral small vessel disease (SVD) requires specific and long-lasting evaluations performed by experienced neuropsychologists. Simpler tools would be helpful for daily clinical practice.
Objective: To determine whether a simple reaction time task that lasts 5 minutes and can be performed without external supervision on any tablet or laptop can be used as a proxy of early cognitive and behavioral alterations in CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy), a monogenic form of pure SVD related to NOTCH3 mutations.
Methods: Twenty-two genetically confirmed patients with CADASIL having preserved global cognitive abilities and without disability (MMSE >24 and modified Rankin’s scale ≤1) were compared to 29 age-and-gender matched controls to determine group differences according to: 1) conventional neuropsychological and behavioral testing; 2) a computerized battery evaluating reaction time, processing speed, and executive functions. In a second step, correlations between reaction time and cognitive and behavioral alterations detected using both conventional and computerized testing were tested in patients.
Results: Reaction time was significantly higher in patients than in controls (mean in patients: 283 ms – in controls: 254 ms, p = 0.03). In patients, reaction time was significantly associated with conventional and chronometric tests of executive functions, working memory, and apathy.
Conclusion: Reaction time obtained using a very simple task may serve as a proxy of early cognitive and behavioral alterations in SVD and could be easily used in daily clinical practice.
Keywords: Apathy, CADASIL, cerebral small vessel disease, cognitive impairment, processing speed, reaction time
