Dietary folate intake and serum folate levels in children with juvenile idiopathic arthritis

Aim - to assess dietary folate intake, serum folate levels, and their associations with disease characteristics in children with juvenile idiopathic arthritis (JIA). Materials and methods. A prospective cohort study was conducted including children with JIA and healthy controls. Dietary folate intake was assessed using a food frequency questionnaire. Serum folate concentrations were measured by enzyme-linked immunosorbent assay. Disease activity was evaluated using the Juvenile Arthritis Disease Activity Score (JADAS-27). Results. Insufficient dietary folate intake was observed in most JIA children (96.46%) and healthy controls (87.88%), with significantly lower median daily folate intake in JIA group. In contrast, JIA children had significantly higher serum folate concentrations and a lower prevalence of folate deficiency or possible deficiency than healthy controls (14.58% vs. 51.61%, respectively). This finding is likely explained by routine folic acid supplementation in patients receiving methotrexate therapy. No significant associations were found between serum folate concentrations and JIA disease activity, disease duration, or disease subtype. Folate deficiency or possible deficiency in children with JIA was associated with rural residence. Conclusions. Despite inadequate dietary folate intake, children with JIA had higher serum folate concentrations than healthy peers, most likely due to folic acid supplementation during methotrexate treatment. The high prevalence of folate deficiency in the general pediatric population highlights the importance of addressing micronutrient insufficiency. The research was carried out in accordance with the principles of the Helsinki Declaration. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.