Impact of COVID-19 infection among myasthenia gravis patients- a Cerner Real-World Data™ study

Background: Myasthenia gravis (MG) is an auto-immune disease, and the mainstay of therapy is immunomodulation. Such patients are at high risk of acquiring any infections. Hence, we sought to determine the impact of the current global pandemic COVID-19 infection in MG patients. Methods: For our study, we used Cerner Real-World Data (TM) that was provided through Cerner's HealtheDataLab research tool. We ran a database query from January 2019 to July 2020 in our study and identified myasthenia patients with and without COVID-19 infection. To extract these patients' data, we used ICD 9-CM, ICD-10, and SNOMED-CT codes. We reported the data using means, range, and prevalence rates, and the p-values were calculated using the two-sample t-test and Pearson's chi-squared test. Results: In the COVID-19 data set, a total of twenty-seven myasthenia patients were identified with a positive COVID-19 infection, and four were diagnosed with an exacerbation. The male to female ratio was equal and one unknown gender (3.7%) with a mean (+/- SD) age of 64.33 +/- 18.42 years. This study group was compared with a non-COVID-19 data set in which a total of sixty-four myasthenia patients were identified, and twenty-three had an exacerbation. Among the 13 hospitalized patients in the two groups, the mean length of hospitalization for the myasthenia patients in the COVID-19 data set was 8.28days (n = 7), and the non-COVID-19 set was 4.33 days (n =6), and it was statistically significant (p-value= 0.007). Conclusions: The mean length of hospital stay is prolonged in myasthenia patients who tested positive for COVID-19.