The Prevalence and Risk Factors of Iron Deficiency Anemia in Thai Infants by Complete Blood Count at 9-Month-Old

Abstract

Background: Infants are the most at risk from iron deficiency (ID) and iron deficiency anemia (IDA), but the prevalence of the latter in this group is unclear. Estimation as to the prevalence of IDA using Hb of less than 11 g/dL may have been exaggerated due to thalassemia and hemoglobinopathies. On the other hand, iron studies are costly and not routinely available in low resource settings. In the present research, the authors estimated the prevalence of IDA in 9-month-old infants at the authors’ well-baby clinic by improving the post-iron-treatment criteria of Hb and defined the risk factors of IDA in infants. Objective: To estimate the prevalence of IDA in 9-month-old infants at the well-baby clinic and to define the risk factors of IDA. Materials and Methods: A retrospective cohort study of 391 children who had complete blood count (CBC) screening at 9-month-old at the well-baby clinic. Anemia was defined according to the WHO criteria (hemoglobin of 11 g/dL or less for children aged six months to five years). IDA was defined as an increase of at least Hb 1 g/dL after receiving iron treatment for one to two months. Mean levels of hematological parameters were compared between groups using independent samples t-test. The characteristics with potential risk factors for IDA were compared with iron non-responder and normal group. Multivariable adjusted odd ratios and 95% confidence intervals (CIs) of IDA were calculated using multinomial logistic regression with control for risk factors. Results: One hundred fourteen children (29.1%) were anemic. There was no difference between anemic and non-anemic children in baseline characteristics. Seventy children in the anemic group were diagnosed with IDA. The prevalence of IDA in the present study was 17.9%. The IDA group showed significant improvement in Hb, Hct, MCV, MCH after receiving iron treatment, but there were no significant changes in the iron non-responder group. The risk factor for IDA was exclusive breastfeeding for at least six months (odds ratio 3.14, 95% CI 1.67 to 5.90, p<0.001). Conclusion: The prevalence of IDA and anemia in the present study was 17.9% and 29.1%, respectively. The risk factor for IDA was exclusive breastfeeding for at least six months. © JOURNAL OF THE MEDICAL ASSOCIATION OF THAILAND 2020.