Iron metabolism in non-anemic myasthenia gravis patients: A cohort study

Background: The association of iron metabolism parameters with disease severity and outcome in myasthenia gravis (MG) patients has not been reported. This study was conducted to determined clinical factors including iron metabolism parameters correlated with disease severity and future outcome in non-anemic immunotherapynaive MG patients first receiving immunotherapy. Material and methods: One hundred and ten patients were included at baseline to explore predictor variables associated with disease severity represented by variables derived from MG activities of daily living (MG-ADL) score using multivariate logistic regression, after which 103 and 98 patients were included respectively in multivariate survival analyses at 6-month and 12-month follow-up to identify predictors for minimal manifestation status (MMS) after starting immunotherapy. Results: Higher ferritin level was independently associated with higher risk of severe generalized disease in nonanemic immunotherapy-naive MG patients. Total iron binding capacity <250 mu g/dL and the interval between onset and immunotherapy <1 year were independent predictors for MMS at 6-month and 12-month follow-up after initiating immunotherapy. Transferrin <2.00 g/L was an independent predictor for MMS at 12-month follow-up. Conclusion: Iron metabolism parameters might be promising biomarkers for evaluating disease severity and guiding therapeutic decision in MG patients.