Short‐term changes in serum miRNA levels and patient‐reported clinical outcomes in myasthenia gravis

Abstract

AbstractIntroduction/AimsThe circulating microRNAs (miRNAs) miR‐150‐5p, miR‐30e‐5p, and miR‐21‐5p have been suggested as potential biomarkers for myasthenia gravis (MG); however, the relationships between short‐term natural changes of the miRNAs and patient‐reported MG outcome scores have not been well‐studied. We assessed the short‐term fluctuations in miRNA levels and patient‐reported outcome measures in MG.MethodsThis prospective cohort study included 39 MG patients with regular follow‐ups and unchanged medications at the Neurology outpatient clinic at Uppsala University Hospital. Patients had weekly follow‐up visits for 1 month, at which blood samples were drawn, and scores from MG activities of daily living (MG‐ADL), MG quality‐of‐life‐15 (MG‐QoL15), and Fatigue Severity Scale (FSS) were assessed. Serum levels of miRNA miR‐150‐5p, miR‐30e‐5p, and miR‐21‐5p were analyzed using quantitative real‐time PCR.ResultsIntra‐individual levels of miR‐30e‐5p and miR‐150‐5p were stable, whereas a significant reduction in miR‐21‐5p was observed from week 1 to week 2 (p = .0024) and from week 2 to week 3 (p < .0001). There were intra‐individual differences over a short time in MG‐ADL, with higher scores in female patients (p = .0281) and a significant reduction from the first to the second weeks (p = .0281), whereas MG‐QoL15 and FSS scores were stable.DiscussionThe suggested MG biomarkers miR‐30e‐5p and miR‐150‐5p were more stable than miR‐21‐5p over a short time, indicating their short‐term stability as biomarkers. Prospective multi‐center studies with longer periods of follow‐up and matched controls are needed to validate these miRNAs as biomarkers in MG.