Prevalence of Folate Deficiency among Rheumatoid Arthritis Cases Taking Methotrexate Presenting with Macrocytic Anemia or Pancytopenia

Aim: Low-dose methotrexate is an anchor drug in the treatment of patients with rheumatoid arthritis (RA), which is an antifolate agent and may lead to folate deficiency.Although the antifolate effect of the drug is a dose-dependent one, the folic acid is supplemented with a universal low-dose regimen (5 mg twice a week) across different doses (7.5-25 mg per week) of methotrexate.The aim of the study is to see the adequacy of low-dose folic acid supplementation in RA patients receiving different doses of methotrexate and who present with macrocytic anemia or pancytopenia.Methods: This was a single-center cross-sectional study.Serum folate levels were measured in rheumatoid arthritis patients taking methotrexate in doses of 7.5-25 mg per week for more than 3 months and taking folic acid 5 mg twice weekly, who presented with macrocytic anemia or pancytopenia.Categorical analysis was performed between methotrexate dose and serum folate level.Results: Among 115 patients included in the study, 86.1% were female, 92.2% had macrocytic anemia, and 7.8% had pancytopenia.A total of 7% patients were folate deficient.However, there was no significant association between methotrexate dose and serum folate level on categorical analysis.Conclusion: Folic acid deficiency does occur in rheumatoid arthritis patients taking methotrexate, but the current practice of folic acid supplementation of 5 mg twice a week is adequate for most of the patients.