Prevalence of iron deficiency in Vietnamese children with congenital heart defects before and after surgery: an observational study.

BACKGROUND

Iron deficiency (ID) is a common nutritional disorder and a leading cause of anemia worldwide, particularly affecting children with congenital heart defects (CHD). Despite its clinical importance, data on the prevalence of ID in pediatric CHD patients, especially in low- and middle-income countries, remain limited. This study aimed to assess the prevalence of iron deficiency and anemia in Vietnamese children with CHD before and after surgical repair, and to identify associated risk factors.

METHODS

We conducted a cross-sectional observational study at the University Medical Center in Ho Chi Minh City, Vietnam, from January to September 2023. A total of 151 children with CHD were included: 81 preoperative and 70 postoperative patients. Children with confounding conditions or recent iron supplementation were excluded. Iron deficiency was defined using both the British Society for Haematology (BSH) and the AHA/ACC/HFSA criteria. Hematological and biochemical parameters were measured, and logistic regression was used to explore associations between clinical characteristics and iron deficiency.

RESULTS

Preoperative iron deficiency was observed in 46.9% of patients using BSH criteria and 87.7% using AHA criteria. Postoperative prevalence decreased to 34.3% and 75.7%, respectively. Cyanotic patients had significantly higher red blood cell indices and lower ferritin and transferrin saturation compared to acyanotic patients preoperatively; these differences were no longer observed after surgery. Anemia prevalence was relatively low, with mostly mild cases (16% preoperative and 11.4% postoperative). Univariate analysis identified age under five years and lower preoperative weight as risk factors for iron deficiency; however, these associations were not statistically significant in multivariate models.

CONCLUSIONS

Iron deficiency is highly prevalent among Vietnamese children with CHD, particularly before surgical repair, and persists in a substantial proportion even after surgery. The findings highlight the need for routine screening and targeted nutritional interventions throughout the perioperative period to improve long-term outcomes in this vulnerable population.

TRIAL REGISTRATION: Not applicable.