In patients with acute ON, obesity was associated with a higher odds ratio (OR) of subsequent MOGAD diagnosis (OR 5.466, 95% CI [2.039, 14.650], p = 0.001) compared with AQP4-IgG+ NMOSD (Supplementary Table 1). This evidence concerns the gene AQP4 and obesity due to melanocortin 4 receptor deficiency.