HAMP and anemia (phenotype): Considering this, inflammation or anemia may be simultaneously related to AS and the four iron homeostasis indicators in this study (ferritin, serum iron, TIBC, TSAT). AS-related anemia and inflammation-induced upregulation of hepcidin may account for the observed association between AS and the four iron homeostasis indicators. Nonetheless, this does not provide evidence of a direct genetic causal relationship between AS and iron homeostasis indicators. Furthermore, these indicators are susceptible to other diseases that cause inflammation and anemia