Patients with myasthenia gravis at High risk of Covid severity: JAMA

Compared to matched controls, persons with myasthenia gravis (MG) who caught COVID-19 had a greater risk of hospitalization and mortality, says an article published in the Journal of American Medical Association Network.

Data on COVID-19 results, vaccination uptake, and safety in myasthenia gravis patients are scarce. Therefore, a population-based sample of people with MG was used in this study to examine COVID-19-related outcomes and vaccination uptake. Monica Alcantara and colleagues.

Administrative health data were utilized in this population-based cohort research in Ontario, Canada, between January 15, 2020, and August 31, 2021. An algorithm was used to identify adults with MG. Each patient was compared to five general population and rheumatoid arthritis (RA) cohort controls based on their sex, age, and place of residence. For this investigation, matched controls and patients with MG were taken into consideration. The primary outcomes were 30-day mortality among patients with MG compared to controls, COVID-19 infection and associated hospitalizations, and admissions to critical care units. In contrast to controls, individuals with MG had a higher uptake of the COVID-19 vaccine as secondary outcomes.

The key findings of this study were:

1. From a total of 11 365 233 eligible inhabitants of Ontario, 4411 patients with MG were matched to 22 055 general population controls and 22 055 controls with RA.

2. 38 861 of 44 110 people in the matched cohort and 3901 (88.4%) of the people in the MG cohort both lived in cities.

3. 164 individuals with MG (3.7%), 669 people in the general population (3.0%), and 668

people with RA (3.0%) all caught COVID-19 between January 15, 2020, and May 17, 2021.

4. Patients with MG reported greater rates of COVID-19-related emergency department

visits, hospital hospitalizations, and 30-day mortality as compared to general population controls and controls with RA.

5. By August 2021, 137 (3.1% of MG patients) and 628 (2.8%) of general population controls had each received one dose of the COVID-19 vaccination, compared to 3540 MG patients (80.3%) and 17 913 general population controls (81.2%), respectively.

6. Less than 6 were hospitalized for MG worsening within 30 days after immunization out of 3461 initial vaccine doses for MG patients.

7. Patients with MG who had received a vaccination had a decreased chance of developing COVID-19 than those who had not.

In conclusion, individuals with MG who developed COVID-19 had a greater probability of being hospitalized and dying than matched controls did. The immunization rate was high, and there was little chance that it would cause severe MG exacerbations following administration. The findings support public health strategies that give persons with MG priority for COVID-19 treatments and immunization.

Reference: 

Alcantara, M., Koh, M., Park, A. L., Bril, V., & Barnett, C. (2023). Outcomes of COVID-19 Infection and Vaccination Among Individuals With Myasthenia Gravis. In JAMA Network Open (Vol. 6, Issue 4, p. e239834). American Medical Association (AMA). https://doi.org/10.1001/jamanetworkopen.2023.9834