Relationship Between Rhabdomyolysis and SARS-CoV-2 Disease Severity

Background Rhabdomyolysis has historically been associated with viral infections, of which influenza A is the most common. A literature review suggests that up to 1/3 of patients hospitalized with COVID-19 develop acute kidney injury (AKI), and of those, nearly half are admitted to the ICU. AKI complicating COVID-19 infection is attributed to several pathogeneses, including sepsis, direct cytopathic effects on the kidneys, and rhabdomyolysis. Objective We aimed to link COVID-19 infection to the development of rhabdomyolysis via creatine kinase (CK) measurement to assess whether this association increases ICU admission, length of stay (LOS), and mortality. Design and setting In this single-center, retrospective cohort study, we enrolled 984 adult patients with confirmed COVID-19 infection requiring admission to a community hospital between March 2020 and May 2021. Measurements Demographic data, laboratory values, and clinical outcomes were collected. The primary outcome measured was the development of rhabdomyolysis and/or AKI. Secondary outcomes included associations of rhabdomyolysis with ICU admission, length of hospital stay, and mortality, utilizing multivariable logistic regression methods. Results Out of the 984 patients included, 39 met the clinical criteria for rhabdomyolysis (4%). The incidence of rhabdomyolysis was higher in patients with AKI (38.3%) and in those who required ICU admission (53.8%) (p<0.001). There was an insignificant difference in death in this cohort (11 patients, 52.4%, p=0.996). However, the mean LOS in patients who had rhabdomyolysis was 18.2 days versus 9.8 days in patients who did not develop rhabdomyolysis (p<0.001). Conclusion Objectively tracking CK levels in COVID-19-infected patients can assist in diagnosing rhabdomyolysis, identifying AKI etiology, and accordingly making a preliminary prognosis for COVID-19 infection, which could direct physicians to initiate more intensive treatment earlier.