Insulin Resistance in Multiple System Atrophy

Fasting blood sample for : glucose, insulinemia, hemoglobin and lipid test to determine the Homeostasis Model Assessment of insulin resistance (HOMA) index

Cognitive evaluation with MOntreal Cognitive Assessment (MoCA)

Severity and progression of motor disorders assessed by the UMSARS scale, severity of dysautonomia assessed by the COMPASS31 scale ; quality of life questionnaire (AMS-Qol) for the level of difficulty experienced by the patient (on activities such as : move; walk; maintain balance; talk; feed)

Brain Magnetic Resonance Imaging (MRI) : putamen imaging, bridge and cerebellum; white substance hypersignals volume

Optional blood sampling for the constitution of a biological collection