Assessment of cerebral hemodynamics in multiple sclerosis patients

Background Multiple sclerosis (MS) is the most common demyelinating disease of the central nervous system. Autonomic dysfunction is present in a wide range of patients (15–80%) that might present with abnormalities in the regulation of the cardiovascular system, sleep disturbance, urinary symptoms, sexual problems, and temperature regulation problem. Although the predominant view is that of an autoimmune inflammatory condition, changes in brain vasculature can occur and contribute to pathophysiology. Objectives The aim of this study was to evaluate cerebral hemodynamics and assess autonomic dysfunction in patients with MS and explore its relationship with disease status. Methods Eighty patients diagnosed with MS according to McDonald criteria 2017 were recruited to this comparative cross-sectional study. All participants underwent assessment of cerebral hemodynamics through transcranial Doppler ultrasonography. Cerebral vasomotor reactivity (CVR) to hypercapnia was measured by the breath-holding index (BHI). They were also assessed for autonomic dysfunction by autonomic questionnaire and blood pressure measurements in both erect and supine positions. Results BHI values showed decreased CVR and were significantly lower in SPMS than in RRMS patients. Autonomic functions were more affected in SPMS than RRMS with total score 2.58 ± 1.13 for the RRMS group and 4.05 ± 1.04 for the SPMS group. Conclusions Cerebrovascular hemodynamic insufficiency in MS may be secondary to the downstream effects of neuro-inflammatory cascades.