Prevalence of anemia in children under 2 years of age according to the cut-off points proposed by the WHO in 2011 and 2024

Abstract

Introduction: Anemia is a public health problem, and children under 2 years old are a vulnerable group. To know the prevalence in a specific population has implications for prevention, diagnosis, and treatment. In March 2024, the WHO changed the hemoglobin (Hb) cut-off point for diagnosing anemia.

 Objetive: To determine the prevalence and severity of anemia in children under 2 years old according to the cutoff points established by the WHO in 2011 and 2024.

Methods: A retrospective cross-sectional observational study. Hemoglobin data from children under 2 years old, attending check-ups at Child Health Observatory of the IDIP and/or had participated in research from 2017 to 2024 were included. The prevalences of anemia (Hb <11 g/dL and <10.5 g/dL) and severity (mild: 10-10.9 g/dL and 9.5-10.4 g/dL; moderate: 7-9.9 g/dL and 7-9.4 g/dL; and severe Hb <7 g/dL for both) were established according to WHO 2011 and 2024 respectively. Prevalences and severity were also determined according to age group (6-12 months, >12-24 months) and sex.

Results: Data from 1843 children were included, 47.7% female. The median age was 6.74 (6.12-12.07) months, with 74.4% under 12 months old. The prevalence of anemia was 46.9% according to WHO 2011 and 25.8% according to WHO 2024, with higher rates in the 6 to 12 months group and no differences by sex. No child presented severe anemia, most cases were mild anemia.

Conclusions: Despite the decrease in the proposed new reference value, anemia continues to be a major public health problem affecting 25.8% of children under 2 years of age in our region. In most cases, the anemia was mild.