The incidence of severe and critical type in MHD patients without anemia versus with anemia was 17.45% versus 28.82% (P = .002), the incidence of severe and critical type in MHD patients without Alb decreased versus with Alb decreased was 14.49% versus 30.10% (P < .001), the incidence of severe and critical type in MHD patients without elevated CRP versus with elevated CRP was 12.96% versus 33.33% (P < .001), all of which mean that the more severe anemia, the lower albumin, and the more severe inflammatory reaction in severe and critical type patients with SARS-CoV-2 infection (Table 3). Here, CRP is linked to anemia (phenotype).