Serum folate and cytokines in heterozygous β‐thalassemia

Introduction Folate deficiency is commonly reported in β‐thalassemia. Individuals heterozygous for β‐thalassemia may have higher folate requirements than normal individuals. Objectives: To document the concentration of serum total folate and its forms in β‐thalassemia heterozygote users (β‐TmU) and nonusers (β‐TmN) of 5 mg folic acid/d; to determine whether folic acid (FA) consumption from fortified foods allows beta‐Tm patients, who do not take FA supplements, to meet their dietary folate requirements; and to investigate the association between higher serum unmetabolized folic acid (UMFA) and inflammatory cytokine concentrations. Methods Serum total folate and forms were measured in 42 β‐Tm (13 β‐TmU and 29 β‐TmN) and 84 healthy controls. The mononuclear leucocyte mRNA expression of relevant genes and their products and hematological profiles were determined. Results β‐TmU had higher serum total folate, 5‐methyltetrahydrofolate, UMFA, and tetrahydrofolate (THF) compared with β‐TmN. The β‐TmN had lower serum total folate and THF than controls. Plasma total homocysteine (tHcy) was lower in β‐TmU compared with both β‐TmN and controls, while β‐TmN had higher tHcy than controls. β‐TmU had higher IL‐8 than their controls while β‐TmN had higher IL‐6 and IL‐8 than their controls. β‐TmU have higher levels of serum total folate, 5‐ methyltetrahydrofolate, UMFA, and THF than controls. There was no association between UMFA concentrations and cytokine levels. Conclusions Mandatory flour fortification with FA in Brazil may be insufficient for β‐TmN, since they have higher tHcy and lower serum total folate than controls. Furthermore, β‐TmN have higher IL‐6 levels than β‐TmU. UMFA was not associated with inflammatory cytokine levels.