Serum hepcidin recalibrated values in Mexican schoolchildren by demographic characteristics, nutritional and infection/inflammation status.

Hepcidin production is regulated by iron concentration, erythropoietic activity, and inflammation. There is no reference method for determining its levels, but results obtained through various methods strongly correlate and can be compared using recalibration equations. OBJECTIVE: To describe recalibrated serum hepcidin values at different percentiles in schoolchildren, considering age, sex, inflammatory processes, H. pylori infection, and iron status. METHODS: Secondary analysis of data incorporating information on inflammation, H. pylori infection, and iron status of 349 schoolchildren. Hepcidin analysis was performed using a competitive ELISA, and recalibrated hepcidin values were calculated using the inverse of the linear regression model equation obtained by van der Vorm et al. Results: Recalibrated hepcidin values were lower than non-calibrated values. In schoolchildren without infection/inflammation and without iron deficiency, recalibrated values at the 50th percentile (25th-75th) were 4.89 ng/mL (2.68-8.42). For schoolchildren without infection/inflammation but with iron deficiency, recalibrated values were 2.34 ng/mL (1.10-6.58), the lowest hepcidin values observed. The highest values were found in the group with infection/inflammation, regardless of iron deficiency status. CONCLUSIONS: Recalibrated hepcidin values were lower than non-calibrated values. The highest values were observed in schoolchildren with infectious or inflammatory processes, and the lowest values were observed in schoolchildren with iron deficiency but only in the absence of infectious or inflammatory processes. Using recalibrated hepcidin values allows comparison between data obtained using different analytical methods.

A Multi-Component Educational Intervention for Addressing Levels of Physical Activity and Sedentary Behaviors of Schoolchildren.

Physical inactivity and a sedentary lifestyle are risk factors for excess weight and obesity in childhood. It is, therefore, necessary to adopt strategies which can modify these behaviors during childhood, the age at which habits are formed. This study aimed to evaluate the impact of an educational intervention using digital media and face-to-face activities involving children, parents, and the school community on the level of physical activity and sedentary behavior among schoolchildren. This was a secondary analysis of data obtained from a community trial in which students from four primary schools in Mexico City participated. Two schools were assigned to the intervention group (IG) and two to the control group (CG). The intervention lasted 12 months and included a face-to-face component, which involved sessions and workshops for parents and children, as well as visual material for children and a distance component utilizing electronic means (web portal and text messages to mobile phones) for parents. Anthropometric measurements were taken and information was collected on moderate to vigorous physical activity performed by the children and on the time that the schoolchildren spent in front of screens at the beginning of the study and at 6 and 12 months. Information on 201 children from the IG and 167 children from the CG was included in the analysis. At 12 months, the IG showed a mean decrease of 33.4 min/d [95% CI: -53.5 to -13.3] in screen time, while the CG showed an increase of 12.5 min/d [CI 95%: -10.5 to 35.6], p = 0.003. After 12 months of follow-up, applying this educational intervention reduced the time that schoolchildren spent in front of screens. Educational intervention is a feasible and accessible strategy for promoting changes in sedentary behaviors in the school-age population.

Epstein-Barr Virus Infection Is Associated with Elevated Hepcidin Levels.

EBV and Helicobacter pylori (H. pylori) cause highly prevalent persistent infections as early as in childhood. Both pathogens are associated with gastric carcinogenesis. H. pylori interferes with iron metabolism, enhancing the synthesis of acute-phase proteins hepcidin, C-reactive protein (CRP), and α-1 glycoprotein (AGP), but we do not know whether EBV does the same. In this study, we correlated the EBV antibody levels and the serum levels of hepcidin, CRP, and AGP in 145 children from boarding schools in Mexico City. We found that children IgG positive to EBV antigens (VCA, EBNA1, and EA) presented hepcidin, AGP, and CRP levels higher than uninfected children. Hepcidin and AGP remained high in children solely infected with EBV, while CRP was only significantly high in coinfected children. We observed positive correlations between hepcidin and EBV IgG antibodies (p < 0.5). Using the TCGA gastric cancer database, we also observed an association between EBV and hepcidin upregulation. The TCGA database also allowed us to analyze the two important pathways controlling hepcidin expression, BMP−SMAD and IL-1ß/IL-6. We observed only the IL-1ß/IL-6-dependent inflammatory pathway being significantly associated with EBV infection. We showed here for the first time an association between EBV and enhanced levels of hepcidin. Further studies should consider EBV when evaluating iron metabolism and anemia, and whether in the long run this is an important mechanism of undernourishment and EBV gastric carcinogenesis.

Evidence of Unhealthy Dietary Patterns in the School Lunch Sent from Home for Children in Mexico City.

The identification and characterization of dietary patterns are tools that are used to assess associations between diet and health or disease conditions. In Mexico, studies have examined dietary patterns in children for breakfast or for the whole day, but not specifically for their school lunch. The aim was to describe dietary patterns identified in school lunch and their association with the nutritional status and metabolic parameters of schoolchildren. In this cross-sectional study on schoolchildren from four elementary schools of Mexico City, we recorded anthropometry measurements, a fasting blood sample was collected, and metabolic parameters were determined. We obtained information on the foods and beverages that children brought for their school lunch; estimated the caloric and nutritional content; and created food groups to obtain dietary patterns from the energy provided by those groups. Among the 350 schoolchildren (mean age, 7.9 ± 1.2 years) included, 24.9% and 21.7% presented having overweight and obesity, respectively. A total of 89.4% of schoolchildren brought the school lunch from home. Using the K-means method, the following four dietary patterns were identified: (1) sandwiches, tortas, and sweetened dairy products were consumed by 13.1% (n = 46) of the schoolchildren; (2) sweet snacks were consumed by 50.3% (n = 176); (3) sweetened dairy products were brought by 15.1% of the children (n = 53); and (4) sandwiches and tortas were brought by 21.4% (n = 75). These four patterns showed significant differences in terms of the caloric and nutritional contents (p < 0.001). Energy sources in the identified patterns were primarily sugars (15.8-40%). No association was found between the anthropometric and metabolic parameters of children and the dietary patterns. No dietary pattern obtained from the school lunch could be considered as healthy, since all of them had high energy content, and a high percentage of the energy was from sugars from ultra-processed foods and beverages.

Nutritional Characteristics, Sites of Origin, and Cost of Foods Consumed during School Hours and Their Relationship to Nutritional Status of Schoolchildren in Mexico City.

Access, nutritional characteristics, preferences, and cost can affect food intake at school. A cross-sectional study was performed to determine the nutritional characteristics, sites of origin, and cost of foods consumed during school hours. Three hundred and sixty-nine children from five public elementary schools in Mexico City participated. The children gave information about the foods that they consumed five days out of the week during school hours, including the place of acquisition, cost of the food, and portion size. Anthropometric measurements of height and weight of the children were taken. Caloric consumption and percentage of recommended daily energy intake from food during school hours was determined. Children were 10.9 ± 0.9 years old; 55.6% were girls, 26% were overweight, 23% were obese, and 3.3% were of low height for age. The average calorie intake was 515 kilocalories (kcal) (boys, 535 kcal; girls, 476 kcal, p = 0.051); calorie intake was higher when school meal intakes included foods from home, school, and outside of school. No significant differences were found in calorie intake by children's nutritional status. The cost in Mexican pesos per 100 kcal consumed showed differences according to the nutritional status of the children; it was 4.0 Mexican pesos for children with normal weight and 4.2 and 3.8 pesos in children who were overweight or obese, respectively. The information obtained in this study should be used to provide nutritional guidance. The food portion size intake during school hours should be reduced, and the food should come from one or at most two sites, because each extra food represents an increase in the total kilocalorie intake.

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.

Hepcidin and other indicators of iron status, by alpha-1 acid glycoprotein levels, in a cohort of Mexican infants.

The purpose of this study was to describe the changes in iron status indicators at 6 and 12 months of age, controlling by inflammation by measuring alpha-1 acid glycoprotein (AGP). This longitudinal study included 48 healthy-term singleton infants with birth weight ≥ 2500 g, born in hospitals of the Mexican Institute for Social Security. Complete blood count, ferritin, soluble transferrin receptor (sTfR), hepcidin, and AGP were measured in blood at 6 and 12 months of age. sTfR/ferritin ratio and total body iron (TBI) stores were calculated. Hemoglobin and sTfR/ferritin ratio increased with age, while ferritin and TBI decreased. In infants without inflammation, hepcidin, sTfR, and MVC did not show significant changes from 6 to 12 months of age, while ferritin and TBI decreased. In infants with inflammation, hepcidin, TBI, and ferritin levels increased, while hemoglobin and sTfR/ferritin ratio decreased. MVC and sTfR did not change significantly in the presence or absence of inflammation. Hepcidin concentration correlated positively and significantly with ferritin and TBI stores and showed significant negative correlation with sTfR/ferritin ratio. Our study showed that, in absence of inflammation and ID, during the first year of life, physiological changes occur in hemoglobin and ferritin levels as well as in indicators derived from ferritin and sTfR; in contrast, hepcidin and sTfR did not show significant change. However, hepcidin concentration was lower in infants with ID and was higher when inflammation was present, supporting that infants have a functional hepcidin response to changes in iron stores.

Association between Active H. pylori Infection and Iron Deficiency Assessed by Serum Hepcidin Levels in School-Age Children.

Hepcidin regulates iron metabolism. Its synthesis increases in infection and decreases in iron deficiency. The aim of this study was to evaluate the relationship between H. pylori infection and iron deficiency by levels of hepcidin in children. A total of 350 school-age children participated in this cross-sectional study. Determinations of serum ferritin, hemoglobin, hepcidin, C-reactive protein, and α-1-acid-glycoprotein were done. Active H. pylori infection was performed with a 13C-urea breath test. In schoolchildren without H. pylori infection, hepcidin was lower in those with iron deficiency compared to children with normal iron status (5.5 ng/mL vs. 8.2 ng/mL, p = 0.017); while in schoolchildren with H. pylori infection the levels of hepcidin tended to be higher, regardless of the iron nutritional status. Using multivariate analysis, the association between H. pylori infection and iron deficiency was different by hepcidin levels. The association between H. pylori and iron deficiency was not significant for lower values of hepcidin (Odds Ratio = 0.17; 95% Confidence Interval [CI] 0.02-1.44), while the same association was significant for higher values of hepcidin (OR = 2.84; CI 95% 1.32-6.09). This joint effect is reflected in the adjusted probabilities for iron deficiency: Individuals with H. pylori infection and higher levels of hepcidin had a probability of 0.24 (CI 95% 0.14-0.34) for iron deficiency, and this probability was 0.24 (CI 95% 0.14-0.33) in children without H. pylori infection and lower levels of hepcidin. In children with H. pylori infection and iron deficiency, the hepcidin synthesis is upregulated. The stimulus to the synthesis of hepcidin due to H. pylori infection is greater than the iron deficiency stimulus.

Helicobacter pylori infection and serum leptin, obestatin, and ghrelin levels in Mexican schoolchildren.

BackgroundThere is little information about the possible role of Helicobacter pylori infection on appetite-regulating peptides in children. This study evaluated the association between H. pylori infection and serum levels of ghrelin, leptin, and obestatin in schoolchildren.MethodsOne hundred seventy-eight schoolchildren, students at boarding schools in Mexico City, participated. H. pylori infection status was determined every 6 months for 1 year by a breath test using 13C-urea; schoolchildren with consistently positive or negative results were selected to participate. Age, sex, and body mass index (BMI) were recorded. Serum concentrations of total ghrelin, leptin, and obestatin via specific enzyme-linked immunosorbent assays were determined.ResultsSchoolchildren with H. pylori infection had lower concentration of leptin, -0.54 pg/ml (95% CI: -0.98 to -0.09), compared to the schoolchildren without infection, after adjustment by age, gender, and BMI. And the children with the infection had a median of obestatin lower in 0.99 ng/ml (95% CI: -1.93 to -0.06) compared with the uninfected children after adjustment by BMI.ConclusionAssociation was found between H. pylori infection and decreased serum concentrations of leptin and obestatin. These results suggest that in schoolchildren, H. pylori infection affects the levels of hormones implicated in regulating appetite and energy homeostasis.

Effect of supplementation with ferrous sulfate or iron bis-glycinate chelate on ferritin concentration in Mexican schoolchildren: a randomized controlled trial.

BACKGROUND: Iron deficiency is one of the most common nutritional deficiencies worldwide. It is more prevalent when iron requirements are increased during pregnancy and during growth spurts of infancy and adolescence. The last stage in the process of iron depletion is characterized by a decrease in hemoglobin concentration, resulting in iron deficiency anemia. Iron deficiency, even before it is clinically identified as anemia, compromises the immune response, physical capacity for work, and intellectual functions such as attention level. Therefore, interventions addressing iron deficiency should be based on prevention rather than on treatment of anemia. The aim of this study was to compare short- and medium-term effects on ferritin concentration of daily supplementation with ferrous sulfate or iron bis-glycinate chelate in schoolchildren with iron deficiency but without anemia. METHODS: Two hundred schoolchildren from public boarding schools in Mexico City who had low iron stores as assessed by serum ferritin concentration but without anemia were randomly assigned to a daily supplement of 30 mg/day of elemental iron as ferrous sulfate or iron bis-glycinate chelate for 12 weeks. Iron status was evaluated at baseline, one week post-supplementation (short term), and 6 months (medium term) after supplementation. RESULTS: Ferritin concentration increased significantly between baseline and post-supplementation as well as between baseline and 6 months after supplementation. One week post-supplementation no difference was found in ferritin concentration between iron compounds, but 6 months after supplementation ferritin concentration was higher in the group that received bis-glycinate chelate iron. However, there is no difference in the odds for low iron storage between 6 months after supplementation versus the odds after supplementation; nor were these odds different by type of supplement. Hemoglobin concentration did not change significantly in either group after supplementation. CONCLUSIONS: Supplementing with 30 mg/d of elementary iron, either as ferrous sulfate or iron bis-glycinate chelate for 90 days, showed positive effects on increasing ferritin concentration in schoolchildren with low iron stores, and this effect persisted 6 months after supplementation.

Present and past Helicobacter pylori infection in Mexican school children.

BACKGROUND: In developing countries, more than 50% of children have serological evidence of Helicobacter pylori infection. However, serological tests for H. pylori did not differentiate between active and past infection. The objectives of this study were to estimate the frequency of active and past H. pylori infection utilizing functional urea breath test (UBT) and serological tests and evaluate factors associated with the infection. METHODS: A total of 675 school children, 6-13 years of age, participated. UBT was performed to detect active H. pylori infection. Blood samples were obtained to determine iron status and Immunoglobulin G (IgG) responses to the H. pylori whole-cell and to Cag A antigens by antigen-specific enzyme-linked immunosorbent assays. Weight, height, and sociodemographic characteristics were recorded. RESULTS: A total of 37.9% (95% Confidence Intervals (CI): 34.2-41.6) of school children had active or past H. pylori infection; of them, 73.8% (CI95% 68.4-79.2) were carrying CagA-positive strain, 26.5% (CI95% 23.2-29.8) had active infection, and 11.4% (95%CI: 9.0-13.8) had evidence of past H. pylori infection. School children with iron deficiency and low height for age had higher risk of H. pylori infection: [OR to active or past infection was 2.30 (CI 95% 1.01-5.23) and to active infection it was 2.64 (CI 95% 1.09-6.44)] compared to school children with normal iron status and height for age or with normal iron status but low height for age or with iron deficiency and normal height for age. CONCLUSIONS: The estimated prevalence of infection depends of the test utilized. Frequency of H. pylori infection and carrying CagA-positive strains was high in this population. Malnutrition was associated with active H. pylori infection.