P4‐181: Obesity as a Risk Factor in the Early Stage of Neurodegeneration: Relationship Between Body Mass Index and Brain Structure

Abstract

database (www.ppmi-info.org/data), corresponding to newly diagnosed PD patients (n¼198) and an age-matched control group (n¼93). Results: We performed 10-fold cross-validation experiments and measured grading values for the substantia nigra (SN) and subthalamic nucleus (STN). The classifier performance was tested by estimating the Area Under the receiver operating characteristic Curve (AUC). Our results showed statistically significant differences in grading values for left SN (p¼0.013) and left STN (p¼0.0002) between patients and controls. When used to classify individual subjects in the cross-validation experiment the performance of the classifier yields an AUC¼0.662 for the left SN, and AUC¼0.733 for the left STN. Conclusions: We have shown that our method could be applied for detecting PD with AUC similar to Alzheimer Disease vs NC detection shown previously (AUC¼0.73 for hippocampal grading in AD, Coupe et al, 2015).