CD38 and anemia (phenotype): The levels of peripheral blood mononuclear cells CD34 and CD38 were significantly higher in the anemic group (23.40 ± 14.63 ng/mL and 1.73 ± 0.83 ng/mL) than the non-anemic group (17.81 ± 10.57 ng/mL and 1.37 ± 0.74 ng/mL), which proves that these cells participate in the compensation mechanism in age-associated anemia.