CLDN1 and chronic kidney disease: Studies have shown that a total of 60 predictors can assess the severity of COVID-19, of which 7 factors are considered to be highly correlated and consistent, including SOFA score, age, d-dimer, hs-CRP, body temperature, albumin, and diabetes.[12] The results of this study revealed that SOFA score, age, CKD, CLD1, CLD2, cystatin C, hs-CRP, CK, CK-MB, and other factors were independent risk factors for in-hospital death, which was similar to the results of the above study.