When the relationships among Th17‐related cytokines were investigated, we found that in HT patients, the plasma levels of IL‐17a were positively correlated with the levels of IL‐22, IL‐23, IL‐6, and IL‐10 (Figure 2A); additionally, IL‐22 was correlated with IL‐6, IL‐23, and IL‐10 (Figure 2B). Here, IL17A is linked to hematocrit.