A higher BMI was significantly associated with a diagnosis of MOGAD-ON (p < 0.001); in MOGAD patients the mean BMI was 31.6 kg/m2 (standard deviation (SD) 7.2), while the mean BMI was 24.7 kg/m2 (SD 5.3) in AQP4-IgG+ NMOSD patients, and 26.9 kg/m2 (SD 6.2) in MS patients. This evidence concerns the gene AQP4 and myeloid sarcoma.