J01 Cognitive alterations in Huntington's disease

Abstract

Cognitive impairment constitutes one of the triad symptoms characterising Huntington9s disease (HD). Nevertheless, while some patients can remain relatively stable for a long time, others can exhibit cognitive defects for more than 15 years prior the diagnosis. The role of cognition in HD is under the focus of interest by the urgent need for objective biomarkers to track and attack the evolution of HD from the pre-symptomatic stage (preHD). Longitudinal follow-up studies demonstrated by means of neuropsychological testing some significant changes differentiating HD patients from preHD and controls. However, the differentiation between controls and preHD resulted controversial. Recent neuroimaging studies demonstrated -by means of progression of cortical thinning- a significant reduction in posterior-cortical areas in preHD population. However, most of the studies focused over cognitive assessment in HD outweighed the assessment of frontal-executive domains over posterior-cortical functions. As occurred in other neurodegenerative disorders, there is a need for a conceptualisation of the concept of mild cognitive impairment in HD based on an accurate differentiation between symptoms heralding different patterns of progression than those without prognostic values. The development of specific instruments for cognitive assessment in HD must represent a necessary step in order to better capture clinically meaningful cognitive symptoms from the preHD stage.