Abstract Details

Rhabdomyolysis was reported after COVID-19 infection.

The reporting rate of rhabdomyolysis after COVID-19 vaccination was compared to the reporting rate of rhabdomyolysis after all other vaccinations in 3 periods: the vaccine period (December 2020-July 2021); the pre-vaccine period (April 2020-November 2020) and the pre-COVID-19 period (January 2019-August 2019). Self-controlled case series analysis and case-centered analysis was used. Six weeks after vaccination was defined as the risk period of probable cause-effect relationship between vaccination and rhabdomyolysis.

169 and 8 cases of rhabdomyolysis after COVID-19 vaccination and all other vaccinations respectively.

During COVID-19 vaccine period, the reporting rate of rhabdomyolysis after COVID-19 vaccination was significantly higher compared to the reporting rate of rhabdomyolysis after all other vaccinations (8.75 vs 0.34 per 10 million p<0.0001). However, it is within the incidence range reported in the general population. Only 4 and 8 cases of rhabdomyolysis after vaccination were reported during pre-vaccine and pre-COVID-19 period respectively.

Using self-controlled and case centered analyses, there is a significant difference in the reporting rate of rhabdomyolysis after COVID-19 vaccination between the risk period and control period (98.22% vs 0.06% p<0.0001). The reporting rate of rhabdomyolysis after Johnson and Johnson was not significantly different from the reporting rate after Moderna and Pfizer vaccinations.

There is no significant increase in cases of rhabdomyolysis with COVID-19 vaccinations. However, the unbalanced distribution of rhabdomyolysis within the first 12 weeks, with a significant increase in reporting rate, suggests that some rhabdomyolysis cases are temporally associated with COVID-19 vaccination. This supports an autoimmune-mediated muscle injury mechanism rather than direct viral muscle invasion for cases of rhabdomyolysis occurring after COVID-19 infections. Due to limitations in passive surveillance, nonreported or undiagnosed concomitant COVID-19 infections cannot be excluded. Controlled studies are needed for further investigation.