The Cognitive Impact of Multiple Sclerosis as a Neurological and Autoimmune Disease: Validation of Cognitive Assessment Tools, Sleep, and Blood Pressure through a Biopsychosocial Lens

This thesis investigates cognitive impairment in Relapsing-Remitting Multiple Sclerosis (RRMS), with a specific focus on executive functions and processing speed. The work integrates neuropsychological assessment with subjective and objective measurements of sleep quality, nocturnal blood pressure, and structural brain markers derived from MRI. The thesis comprises three interconnected studies. The first study validates the Greek versions of the BRIEF-A (self- and informant-report) and the CLOX: an executive clock-drawing task, establishing their reliability, validity in people with MS. The second study examines longitudinal associations between subjective sleep quality, cognitive performance, and MRI-based indices of brain structural change in a cohort of individuals with RRMS. The third study employs wearable technology to capture objective sleep parameters and nocturnal blood pressure, exploring their relationships with executive functioning and identifying meaningful risk profiles. Therefore, the thesis adopts a multidimensional, neuropsychological framework and highlights the value of ecologically valid cognitive measures and non-invasive physiological monitoring for understanding cognitive vulnerability in Multiple Sclerosis