MIF and hematocrit: Increased serum MIF protein levels were found in both HT and HT subsets compared to HC (25.38 ± 13.27 ng/mL, 16.64 ± 8.93 ng/mL, and 36.08 ± 9.26 ng/mL versus 7.89 ± 1.89 ng/mL, all P < 0.01); meanwhile, there were remarkable differences between HT-A and HT-B subgroups (P < 0.01), Figure 3(a).