Cut-off points for serum ferritin to identify low iron stores during the first year of life in a cohort of Mexican infants.

The aim of this study was to identify serum ferritin (SF) cut-off points (COPs) in a cohort of healthy full-term normal birth weight infants who had repeated measurements of SF and haemoglobin every 3 months during the first year of life. The study included 746 full-term infants with birth weight ≥2,500 g, having uncomplicated gestations and births. Participants received prophylactic iron supplementation (1 mg/day of iron element) from the first to the 12th month of life and did not develop anaemia during the first year of life. Two statistical methods were considered to identify COPs for low iron stores at 3, 6, 9 and 12 months of age: deviation from mean and cluster analysis. According to the K-means cluster analysis results by age and sex, COPs at 3 and 6 months for girls were 39 and 21 µg/L and for boys 23 and 11 µg/L, respectively. A single COP of 10 µg/L was identified, for girls and boys, at both 9 and 12 months. Given the physiological changes in SF concentration during the first year of life, our study identified dynamic COPs, which differed by sex in the first semester. Adequate SF COPs are necessary to identify low iron stores at an early stage of iron deficiency, which represents one of the most widespread public health problems around the world, particularly in low- and middle-income countries.

Deficiencia de folatos y su asociación con defectos de cierre del tubo neural en el norte de México / Folic acid deficiency and its relationship with neural tube defects in northern Mexico

Objetivo. Valora la asociación de la deficiencia de folatos y otros factores de riesgo con la ocurrencia de defectos de cierre del tubo neural (DCTN), en la población rural del norte de México (Chihuahua, Durango y Zacatecas). Material y métodos. Se hizo un estudio multicéntrico de casos y controles. Se consideraron como casos a los recién nacidos vivos (RNV) y a los muertos con DCTN, y como controles, a los RNV sanos, no malformados. Se determinó la exposición a factores de riesgo conocidos, estableciendo su asociación con los DCTN, con un modelo de análisis múltiple de regresión logística. Resultados. Los factores de riesgo asociados a DCTN fueron: la deficiencia de folatos (RM 11.1; IC95 por ciento 1.2-106.2, p= 0.04); el antecedente, en embarazos previos, de productos con DCTN (RM 3.3; IC95 por ciento 1.1-18.8, p= 0.05), y óbitos (RM 7.1; IC95 por ciento 1.1-46.3, p= 0.04). Conclusiones. La deficiencia de folatos constituye uno de los principales factores de riesgo asociado a los DCTN en la población rural del norte de México. Es necesario llevar a cabo más investigaciones para determinar la contribución de otros factores de riesgo y establecer las medidas preventivas adecuadas