Variations in clinical features and disease burden of myasthenia gravis between racial and ethnic groups: A retrospective cohort study of two national databases.

Previous studies have reported that clinical characteristics and outcomes of myasthenia gravis (MG) vary across racial and ethnic groups. This study leverages two nationwide datasets, the MG Foundation of America Global MG Patient Registry (MGFAPR) and the National Inpatient Sample (NIS) to further examine these reports. We compared clinical characteristics, socioeconomic determinants, therapeutic regimens, and inpatient outcomes across racial/ethnic groups of MGFAPR enrollees between July 2013 and November 2024 that self-reported MG diagnosis by a physician and were US residents over the age of 18. Of 3744 patients, race was reported for: 3099 White, 178 African American (AA), 47 Asian, and 151 Indigenous patients; ethnicity was reported for: 188 Hispanic and 3431 non-Hispanic patients. AA and Hispanic patients had higher frequencies of early-onset MG and generalized symptoms; AA and Indigenous patients had higher MG-ADL and MG-QOL15r scores at enrollment; and White and Indigenous patients had higher frequencies of comorbid cancer. In the MGFAPR, women were 30 % less likely to be hospitalized and anxiety and/or depression was 300 % more common in hospitalized patients. In the NIS, we identified 62,055 hospitalizations for MG worsening from 2012 to 2019. AA and Hispanic MG patients had 1.4 and 1.7-times greater odds of intubation than White patients. Average cost of hospitalization was 150 % higher for AA patients than White patients. Overall, MG presented differently across racial/ethnic groups: we observed a greater disease burden in terms of ability to perform activities of daily life, quality of life, inpatient outcomes, and hospitalization costs in AA, Hispanic, and Indigenous patients.