Etiology of Anemia in Older Mexican Adults: The Role of Hepcidin, Vitamin A and Vitamin D.

Anemia in older adults is a growing public health issue in Mexico; however, its etiology remains largely unknown. Vitamin A deficiency (VAD) and vitamin D deficiency (VDD) have been implicated in the development of anemia, though by different mechanisms. The aim of this study is to analyze the etiology of anemia and anemia-related factors in older Mexican adults. This is a cross-sectional study of 803 older adults from the southern region of Mexico in 2015. The anemia etiologies analyzed were chronic kidney disease (CKD), nutritional deficiencies (ND), anemia of inflammation (AI), anemia of multiple causes (AMC) and unexplained anemia (UEA). VAD was considered to be s-retinol ≤ 20 µg/dL, and VDD if 25(OH)D < 50 nmol/L. IL-6 and hepcidin were also measured. Multinomial regression models were generated and adjusted for confounders. Anemia was present in 35.7% of OA, independent of sex. UEA, CKD, AI and ND were confirmed in 45%, 29.3%, 14.6% and 7% of older adults with anemia, respectively. Hepcidin and log IL-6 were associated with AI (p < 0.05) and CKD (p < 0.001). VAD was associated with AI (p < 0.001), and VDD with ND and AMC (p < 0.05). Log-IL6 was associated with UEA (p < 0.001). In conclusion, anemia in older adults has an inflammatory component. VAD was associated to AI and VDD with ND and AMC.

Nutritional status of iron, vitamin B12, vitamin A and anemia in Mexican children: results from the Ensanut 2018-19.

OBJECTIVE: To describe the current status of micronutrient deficiencies (MD) and anemia in Mexican children. MATERIALS AND METHODS: Serum data from 1 382 pre-school-age chil-dren (1-4 years) and 3 590 school-age children (5-11 years) Ensanut 2018-19 participants were analyzed. Iron deficiency (ID), vitamin B12 deficiency (B12D), vitamin A depletion (VADp), and anemia were identified. Logistic regression models were used to identify associations between socio-demographic characteristics of children and MD. RESULTS: Anemia was present in 28.9 and 19.2% of the children aged 1-4 and 5-11, respectively; in ID 10 and 5.1%; B12D, in 5.1 and 4.8%, and VADp, in 4.7 and 4.3%. 18.5% of the preschool-age children and 13% of the school-age children had at least one MD associated to anemia. CONCLUSIONS: MD and anemia affect the younger children in larger proportion. Fortification and supplementation programs should be reinforced to avoid the long-term consequences of MD.

Which blood cutoff value should be used for vitamin A deficiency in children aged 3-10 years? A systematic review.

CONTEXT: Blood cutoff values for vitamin A deficiency in children aged 3-10 years have not been addressed in the literature. OBJECTIVE: To identify blood retinol concentrations for determining severe vitamin A deficiency in children aged 3-10 years. DATA SOURCES: The MEDLINE, Web of Science, Embase, and Scopus databases were searched. DATA EXTRACTION: Two reviewers independently extracted article data and assessed quality. DATA ANALYSIS: The hierarchical summary receiver operating characteristic models were applied for the diagnostic accuracy meta-analysis. This review is registered at PROSPERO (identifier: CRD42020149367). RESULTS: A total of 15 articles met the eligibility criteria, and 9 were included in the diagnostic accuracy meta-analysis. The summary estimates (95%CI) were: Sensitivity, 0.39 (0.20-0.62); specificity, 0.79 (0.65-0.88); positive likelihood ratio, 1.85 (1.33-2.57); and negative likelihood ratio, 0.77 (0.60-0.99). The area under the curve of the overall analysis was 0.68 (95%CI 0.63-0.72). CONCLUSIONS: Blood retinol concentrations have low diagnostic accuracy for severe vitamin A deficiency in children aged 3-10 years. Therefore, there is unclear evidence about the preferable cutoff point for determining severe vitamin A deficiency in children in this age group.

DNA damage is inversely associated to blood levels of DHA and EPA fatty acids in Brazilian children and adolescents.

This study aimed to investigate the association between DNA damage and blood levels of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), retinol, beta-carotene and riboflavin in Brazilian children and adolescents. Subjects (n = 140) were healthy boys and girls aged 9 to 13 years in Ribeirão Preto (SP, Brazil). Data collection included anthropometry, assessment of energy intake and blood sampling. DNA damage was evaluated by single-cell gel electrophoresis (comet assay). Principal component analysis (PCA) was used to verify associations between blood concentrations of vitamins, polyunsaturated fatty acids and DNA damage. Multiple regression analyses, k-means cluster, and analysis of covariance (ANCOVA), adjusted for confounding variables such as age, sex, energy intake, body mass index and total cholesterol (when needed), were applied to confirm the associations. PCA explained 69.4% of the inverse relationships between DNA damage and blood levels of DHA, EPA, retinol, and beta-carotene. Results were confirmed by ANCOVA and multiple regression analyses for DHA and EPA. In conclusion, omega-3-fatty acids were inversely associated with DNA damage in Brazilian children and adolescents and may be a protective factor against the development of future diseases.

Vitamin D sufficiency in young Brazilian children: associated factors and relationship with vitamin A corrected for inflammatory status.

OBJECTIVE: To assess sociodemographic, nutritional and health conditions associated with vitamin D sufficiency among young Brazilian children living at different latitudes. DESIGN: Cross-sectional analysis with a four-level model of inflammation to correct micronutrient concentrations. Prevalence ratios (PR; 95 % CI) were estimated for factors associated with vitamin D sufficiency (≥50 nmol/l), adjusting for child's sex, age, skin colour, stunting and vitamin A+D supplementation. SETTING: Primary health-care units in four Brazilian cities located at lower (7°59'26·9016″S and 9°58'31·3864″S) and higher latitudes (16°41'12·7752″S and 30°2'4·7292″S). PARTICIPANTS: In total 468 children aged 11-15 months were included in the analysis. RESULTS: Only 31·8 % of children were vitamin D sufficient (concentration <30 nmol/l and <50 nmol/l among 32·9 and 68·2 %, respectively). Living at higher latitudes was associated with reduced prevalence of vitamin D sufficiency compared with lower latitudes (PR = 0·65; 95 % CI 0·49, 0·85). Maternal education ≥9 years positively influenced a sufficient vitamin D status in children. After correction for inflammatory status, each increase of 1 µmol/l in vitamin A concentration was associated with a 1·38-fold higher prevalence of vitamin D sufficiency (95 % CI 1·18, 1·61). Progressive decline in the prevalence of vitamin D sufficiency was associated with marginal and deficient status of vitamin A (Ptrend = 0·001). CONCLUSIONS: Lower latitude, higher maternal education and vitamin A concentration were positively associated with vitamin D sufficiency in young Brazilian children. These findings are relevant for planning public health strategies for improving vitamin D status starting in early infancy.

Effect of Vitamin A status during pregnancy on maternal anemia and newborn birth weight: results from a cohort study in the Western Brazilian Amazon.

PURPOSE: Inadequate Vitamin A (VA) status during pregnancy has been associated with maternal anemia and suboptimal newborn birth weight (BW). We assessed the effect of gestational serum retinol and ß-carotene (µmol/L), in different moments during pregnancy, on maternal hemoglobin (Hb, g/L) and anemia (Hb < 110.0 g/L) at delivery, and newborn BW (kg). METHODS: In a prospective cohort study in Cruzeiro do Sul, Western Brazilian Amazon, biomarkers of the VA status were assessed in the second and third trimesters in pregnancy. Serum retinol and ß-carotene were analyzed considering their effects in each and in both assessments (combined VA status), and the difference of serum values between assessments. Multiple linear and Poisson regression models were used with a hierarchical selection of covariates. RESULTS: A total of 488 mother-newborn pairs were surveyed. Combined VA deficiency status increased the risk for maternal anemia (adjusted prevalence ratio: 1.39; 95% CI 1.05-1.84), and was negatively associated with maternal Hb (ß - 3.30 g/L; 95% CI - 6.4, - 0.20) and newborn BW (ß - 0.10 kg; 95% CI - 0.20, - 0.00), adjusted for socioeconomic, environmental, obstetric, and antenatal characteristics, and nutritional indicators. However, the association for newborn BW was no longer significant after further adjustment for plasma ferritin. There were no significant associations between serum ß-carotene and the outcomes studied. CONCLUSION: Poor serum retinol status throughout pregnancy was associated with maternal anemia at delivery in Amazonian women. The current World Health Organization protocols for supplementation during antenatal care should consider VA status for planning recommendations in different scenarios.

Diagnosis of night blindness through standardized interview and electroretinography.

INTRODUCTION: Objective: To compare the diagnosis of NB through the use of the standardized interview of the World Health Organization/Pan American Health Organization (WHO/PAHO) with electroretinography, and also to evaluate the association of these diagnoses with serum concentrations of retinol in class III obesity individuals. Methods: Adult patients of both genders, in the 20-60 age group, with BMI ≥ 40 kg/m² were studied. NB was diagnosed through electroretinography and the standardized interview validated by the WHO/PAHO. Serum level of retinol was quantified by the HPLC-UV method, and VAD was diagnosed when levels were <1.05 µmol /L, and severity was also evaluated. Statistical analysis was carried out through the Statistical Package for the Social Sciences, version 21.0 (p < 0.05). Results: Mean BMI was 44.9  11.8 kg/m², and a negative correlation was found in serum levels of retinol (p= 0.01). The prevalence of VAD, according to the serum concentrations of retinol, was 14%, and of this percentage 23.3% had NB according to the standardized interview, and 22.0% according to electroretinography. NB diagnosed by both methods showed an association with VAD according to the serum concentrations of retinol. Of these individuals with NB, according to the standardized interview, 6.9% showed severe VAD, 10.3% moderate VAD and 82.8% marginal VAD. Conclusion: The standardized interview for the diagnosis of NB can be a good strategy to evaluate the nutritional status of vitamin A, and it is a simple, non-invasive and low-cost method.

INTRODUCCIÓN: Objetivo: Comparar el diagnóstico de NB mediante el uso de la entrevista estandarizada de la Organización Mundial de la Salud/Organización Panamericana de la Salud (OMS/OPS) con electrorretinografía, y también evaluar la asociación de estos diagnósticos con las concentraciones séricas de retinol en la clase III personas obesas. Métodos: se estudiaron pacientes adultos de ambos sexos, en el grupo de 20 a 60 años de edad, con un IMC ≥ 40 kg/m². La NB se diagnosticó mediante electrorretinografía y la entrevista estandarizada validada por la OMS/OPS. El nivel sérico de retinol se cuantificó mediante el método HPLC-UV, y el DVA se diagnosticó cuando los niveles eran <1.05 µmol / L, y también se evaluó la gravedad. El análisis estadístico se realizó a través del Paquete Estadístico para las Ciencias Sociales, versión 21.0 (p <0.05). Resultados: IMC promedio fue de 44.9 ± 11.8 kg / m², y se encontró una correlación negativa en los niveles séricos de retinol (p = 0.01). La prevalencia de DVA, según las concentraciones séricas de retinol, fue del 14%, y de este porcentaje, el 23,3% tenía NB de acuerdo con la entrevista estandarizada y el 22,0% según la electrorretinografía. La NB diagnosticada por ambos métodos mostró una asociación con VAD según las concentraciones séricas de retinol. De estos individuos con NB, según la entrevista estandarizada, el 6,9% mostró VAD grave, el 10,3% de VAD moderado y el 82,8% de VAD marginal. Conclusión: la entrevista estandarizada para el diagnóstico de NB puede ser una buena estrategia para evaluar el estado nutricional de la vitamina A, y es un método simple, no invasivo y de bajo costo.

Retinol status and associated factors in mother-newborn pairs.

BACKGROUND: Vitamin A deficiency is still considered to be a nutritional problem during pregnancy, lactation and early childhood. The present study aimed to assess the vitamin A status of women and their newborns in the Brazilian Northeast and to determine the association between retinol in the maternal serum, umbilical cord blood and colostrum. METHODS: Vitamin A status in 65 pairs of women and newborns was assessed from samples of the mother's serum, umbilical cord serum and colostrum using high-performance liquid chromatography. The inadequacy of the vitamin A status of mothers and infants was identified if the retinol values were <0.7 µmol L- 1 in maternal serum or umbilical cord blood or <1.05 µmol L-1 in colostrum. RESULTS: The prevalence of inadequate maternal vitamin A status was 21.5% (95% CI: 11.5%-31.5%) and 13.8% [95% confidence interval (CI) = 5.4%-22.2%] based on maternal serum and colostrum, respectively. Among newborns, 41.5% (95% CI = 29.3%-53.5%) presented a low status of vitamin A based on cord serum. Multiple linear regression analysis identified that maternal serum retinol is a predictor of umbilical cord retinol (P = 0.005). Retinol in maternal serum was lower in mothers who were less educated (P = 0.04) and colostrum retinol was higher in older (P = 0.04) and multiparous (P = 0.002) mothers. CONCLUSIONS: Vitamin A deficiency is a common problem among mothers attended in public hospitals in Northeast Brazil and maternal retinol concentrations are associated with retinol status in newborns. Maternal age, parity and educational level were related to the maternal vitamin A status.

Associação entre insegurança alimentar e níveis de hemoglobina e retinol em crianças assistidas pelo Sistema Único de Saúde no Município do Rio de Janeiro, Brasil / Association between food insecurity and hemoglobin and retinol levels in children treated in the Brazilian Unified National Health System in the city of Rio de Janeiro, Brazil / Asociación entre inseguridad alimentaria y niveles de hemoglobina y retinol en niños asistidos por el Sistema Único de Salud en el municipio de Río de Janeiro, Brasil

Neste trabalho foi analisada a associação entre insegurança alimentar e níveis de hemoglobina e retinol em crianças de 6 a 59 meses de idade. Trata-se de um estudo seccional, realizado em 2014, com amostra representativa da população de crianças nessa faixa etária, atendidas em unidades básicas de saúde do Município do Rio de Janeiro, Brasil. Para a análise dos níveis de insegurança alimentar foi utilizada a Escala Brasileira de Insegurança Alimentar e, para a determinação de hemoglobina e de retinol sérico, foi realizada a punção venosa. A associação entre as variáveis foi avaliada por intermédio de modelos de regressão quantílica. Do total de crianças estudadas, 40,3% apresentavam insegurança alimentar e as prevalências de anemia e de deficiência de vitamina A foram 13,7% e 13%, respectivamente. Os resultados do estudo revelaram associação inversa, estatisticamente significativa, entre insegurança alimentar leve e níveis de retinol. Para os demais níveis de insegurança alimentar (moderada e grave), os resultados também sugerem a presença de associação inversa para hemoglobina e, quanto aos níveis de retinol, as estimativas pontuais parecem menores em crianças com insegurança alimentar grave, entretanto, estas estimativas não foram estatisticamente significativas. Esses resultados sugerem que a insegurança alimentar pode estar associada com carências de micronutrientes em crianças menores de 5 anos.

This study analyzed the association between food insecurity and hemoglobin and retinol levels in children 6 to 59 months of age. This was a cross-sectional study in 2014 with a representative sample of children in this age bracket treated at basic health units in the city of Rio de Janeiro, Brazil. Analysis of food insecurity levels used the Brazilian Food Insecurity Scale, and venipuncture was performed for measurement of serum hemoglobin and retinol levels. The association between variables used quantile regression models. Of all the children in the sample, 40.3% presented food insecurity, and the prevalence rates for anemia and vitamin A deficiency were 13.7% and 13%, respectively. The study's results revealed a statistically significant inverse association between mild food insecurity and retinol levels. For the other levels of food insecurity (moderate and severe), the results also suggest an inverse association for hemoglobin, and for retinol levels the point estimates appear smaller in children with severe food insecurity, but these estimates were not statistically significant. These results suggest that food insecurity may be associated with micronutrient deficiencies in children under 5 years.

En este estudio se analizó la asociación entre la inseguridad alimentaria y los niveles de hemoglobina y retinol en niños de 6 a 59 meses de edad. Se trata de un estudio seccional, realizado en 2014, con una muestra representativa de la población de niños en esta franja etaria, atendida en unidades básicas de salud del Municipio de Río de Janeiro, Brasil. Para el análisis de los niveles de inseguridad alimentaria se utilizó la Escala Brasileña de Inseguridad Alimentaria y, para la determinación de hemoglobina y de retinol sérico, se realizó una punción venosa. La asociación entre las variables se evaluó a través de modelos de regresión cuantílica. Del total de niños estudiados, un 40,3% presentaban inseguridad alimentaria y las prevalencias de anemia y de deficiencia de vitamina A fueron 13,7% y 13%, respectivamente. Los resultados del estudio revelaron una asociación inversa, estadísticamente significativa, entre inseguridad alimentaria leve y niveles de retinol. Para los demás niveles de inseguridad alimentaria (moderada y grave), los resultados también sugieren la presencia de una asociación inversa para la hemoglobina, y, en cuanto a los niveles de retinol, las estimaciones puntuales parecen menores en niños con inseguridad alimentaria grave, sin embargo, estas estimaciones no fueron estadísticamente significativas. Estos resultados sugieren que la inseguridad alimentaria puede estar asociada con carencias de micronutrientes en niños menores de 5 años.

Reduction of Serum Concentrations and Synergy between Retinol, ß-Carotene, and Zinc According to Cancer Staging and Different Treatment Modalities Prior to Radiation Therapy in Women with Breast Cancer.

The procedures used for breast cancer treatment are able to increase the level of oxidative stress and cause depletion of antioxidants. OBJECTIVES: To investigate the relationship between serum concentrations of retinol, ß-carotene, and zinc, according to breast cancer staging, considering different treatment modalities prior to radiation therapy and the synergistic action between these micronutrients. METHODS: This is a cross-sectional observational study comprising a cohort of patients with breast cancer which was carried out prior to radiation therapy. Patients were divided into 3 groups: G1 comprised women who had undergone breast-conserving surgery, G2 comprised those who had undergone chemotherapy, and G3 those who had undergone breast-conserving surgery and chemotherapy. Serum concentrations of retinol, ß-carotene, and zinc were quantified. Breast cancer staging was based on the TNM (Tumor, Node, Metastasis) classification of malignant tumors, a type of staging tool for different cancers. RESULTS: A total of 230 patients were assessed. A decrease of the serum concentrations of the micronutrients assessed as the staging level of the disease increased was observed. Surgery alone had a greater negative impact on serum concentrations of retinol. Considering the treatments prior to radiotherapy, patients undergoing surgery alone and chemotherapy associated with surgery had higher percentages of deficiency of ß-carotene and retinol. There was a positive correlation between the concentrations of zinc, retinol, and ß-carotene, showing a synergy between these micronutrients. CONCLUSION: A significant reduction in the serum concentrations of the assessed micronutrients was observed, according to the increase in breast cancer staging. The synergy between the micronutrients must be considered in order to maximize the benefits and minimize the adverse effects of irradiation to normal cells.

Correlation of serum vitamin A, D, and E with recurrent respiratory infection in children.

OBJECTIVE: To investigate the correlation of serum vitamin A, D, and E levels with a recurrent respiratory infection (RRI) in children. PATIENTS AND METHODS: The medical records of 422 children with RRI (a study group) in Cangzhou Central Hospital from January 2015 to December 2018 were retrospectively analyzed (the study group was divided into an active group and a stable group). Further 100 healthy children who underwent physical examination at the same time were enrolled as a control group. High-performance liquid chromatography (HPLC) was used to determine vitamin A, D, and E levels, so as to analyze their differences between the groups. RESULTS: Vitamin A, D, and E in the active and stable groups were significantly lower than those in the control group (p < 0.001); in the active group they were significantly lower than those in the stable group (p < 0.001). According to partial correlation analysis, in children with active RRI, vitamin A was respectively positively correlated with vitamin D (r=0.945, p < 0.001), and vitamin E (r=0.988, p < 0.001). Moreover, vitamin E was positively correlated with vitamin D (r=0.959, p < 0.001). CONCLUSIONS: The deficiency of vitamin A, D, and E is positively correlated with the disease activity of children with RRI. Therefore, the supplement of vitamin A, D, and E through dietary adjustment is beneficial to the rehabilitation of the children.

Selenium Status and Hemolysis in Sickle Cell Disease Patients.

Sickle cell disease (SCD) is a genetic hemoglobinopathy characterized by chronic hemolysis. Chronic hemolysis is promoted by increased oxidative stress. Our hypothesis was that some antioxidant micronutrients (retinol, tocopherol, selenium, and zinc) would be determinant factors of the degree of hemolysis in SCD patients. We aimed to investigate the nutritional adequacy of these antioxidants and their relationships to hemolysis. The study included 51 adult SCD patients regularly assisted in two reference centers for hematology in the State of Rio de Janeiro, Brazil. Serum concentrations of retinol, alpha-tocopherol, selenium, and zinc were determined by high-performance liquid chromatography or atomic absorption spectrometry. Hematological parameters (complete blood count, reticulocyte count, hemoglobin, direct and indirect bilirubin, total bilirubin, lactate dehydrogenase) and inflammation markers (leukocytes and ultra-sensitive C-reactive protein) were analyzed. A linear regression model was used to test the associations between the variables. Most patients presented selenium deficiency and low selenium consumption. Linear regression analysis showed that selenium is the main determinant of hemolysis among the antioxidant nutrients analyzed. Thus, data from this study suggest that the nutritional care protocols for patients with SCD should include dietary sources of selenium in order to reduce the risk of hemolysis.

The Validity of Children's Fruit and Vegetable Intake Using Plasma Vitamins A, C, and E: The SAYCARE Study.

Despite that fruits and vegetables are key elements for health promotion, there are limited studies validating their intake in children. We aimed to validate the SAYCARE (South American Youth/Child Cardiovascular and Environmental) Study Food Frequency Questionnaire (FFQ) and the combination of the FFQ frequency of intake with the 24 h-dietary-recall (24 h-DR) (mean of 3 days), for children's fruit and vegetable intake. The reference methods were plasma dosages of ß-carotene, retinol, ascorbic acid, and α-tocopherol, which were collected in the school environment. It is a validity study in a subsample of 45 children aged 6-10 years participating in the SAYCARE Study, from São Paulo (Brazil). The FFQ was answered by the parents/guardians over the previous 3 months; the 24 h-DR was answered three times (two weekdays by nutritionists, one weekend day by parents/guardians). The mean fruit and vegetable intake (combined with frequency of intake) was calculated using the multiple source method (MSM). Multiple linear regression showed pooled correlation coefficients of 0.29 to 0.35 for the reported fruit and vegetable intake estimated by the FFQ and the MSM, respectively. The SAYCARE FFQ is an accurate and useful tool for ranking fruit and vegetable intake in children between 6-10 years from the SAYCARE Study.

Prepregnancy Obesity, Maternal Dietary Intake, and Oxidative Stress Biomarkers in the Fetomaternal Unit.

BACKGROUND: Obesity and pregnancy increase levels of maternal oxidative stress (OS). However, little is known about the maternal, placental, and neonatal OS status. OBJECTIVE: To analyze the relation between prepregnancy obesity and the expression of OS markers and antioxidant capacity in the fetomaternal unit and their association with dietary intake. METHODS: This cross-sectional study included 33 women with singleton, noncomplicated pregnancies. Two groups were formed: women with prepregnancy body mass index (pBMI) within normal range (18.5-24.9 kg/m2, n = 18) and women with pBMI ≥ 30 kg/m2, suggestive of obesity (n = 15). Dietary and clinical information was obtained by questionnaire and from clinical records. Total antioxidant capacity (TAC) and malondialdehyde (MDA) concentration were measured on maternal and cord serum by colorimetric techniques, and placental expression of glutathione peroxidase 4 (GPx4) was measured by immunohistochemistry. RESULTS: Placental GPx4 expression was lower in the group with pBMI suggestive of obesity than in the normal weight group (ß = -0.08, p = 0.03, adjusted for gestational age and magnesium intake). Concentrations of TAC and MDA in maternal and cord blood were not statistically different between groups (p>0.05). Cord MDA concentration was related to maternal MDA concentration (ß = 0.40, p < 0.01), vitamin A intake (tertile 2: ß = -0.04, p = 0.40, tertile 3: ß = 0.13, p = 0.03, vs tertile 1), and placental GPx4 expression (ß = -0.09, p = 0.02). CONCLUSION: Prepregnancy obesity is associated with a decrease in GPx4 expression in the placenta, which is related to OS in the newborn. The influence of micronutrient intake on OS biomarkers highlights the importance of nutritional assessment during pregnancy and adequate prenatal care.

Serum Retinol but Not 25(OH)D Status Is Associated With Serum Hepcidin Levels in Older Mexican Adults.

1) Background: Elevated hepcidin levels have been linked to anemia of inflammation (AI). Retinol deficiency has shown to upregulate hepcidin expression in animals, while conflicting evidence links VD status with hepcidin concentration in humans. The purpose of the study is to explore if VA and VD status are associated with hepcidin concentrations in older Mexican adults (OA). 2) Methods: A cross-sectional study was conducted in summer 2015, using serum samples from 783 fasting OA ages 60 and above residents from Campeche and Yucatán. VA deficiency (VAD) was defined as serum retinol concentration <20 µg/dL and VD deficiency (VDD) as 25(OH)D <50 nmol/L. The log-hepcidin was the outcome variable expressed as continuous and tertiles of its distribution. Linear and ordinal regression models were used. 3) Results: VAD was present in 3.4% and VDD in 9.5% of OA. Log-retinol was inversely associated with log-hepcidin (coeff.: -0.15, 95%CI: -0.2, -0.09). VAD status shown a higher probability than non-VAD for higher hepcidin tertiles (OR = 2.15, 95%CI: 1.24, 3.74). VDD states was not associated with hepcidin in the linear (coeff.: 0.16, 95%CI: -0.02, 0.34) nor the ordinal model (OR = 0.74, 95%CI: 0.42, 1.28). 4) Conclusions: VAD, but not VDD, status was inversely associated with hepcidin concentrations in OA.

Effect of vitamin A supplementation on iron status in humans: A systematic review and meta-analysis.

Anemia is a worldwide public health problem that can be related to many causes, including vitamin A deficiency. The aim of this study was to assess and estimate the effect of vitamin A supplementation (VAS) on iron status biomarkers and anemia in humans. Six databases, including Cochrane, EMBASE, LILACS, Pubmed, Scopus and Web of Science, were searched for clinical trials and cohort studies that investigated the effect of vitamin A supplementation alone on iron status and anemia, without time-restriction. The search yielded 23 eligible studies, 21 clinical trials and 2 cohort studies, with children, teenagers, pregnant or lactating women. The meta-analysis of the clinical trials showed that VAS reduces the risk of anemia by 26% and raises hemoglobin levels, compared to non-treated group, independent of the life stage. VAS did not alter the prevalence of iron deficiency among the clinical trials conducted with children and teenagers (RR 0.82, 95% CI 0.60 to 1.12, p = 0.204), whereas a significant increase in serum ferritin levels was observed in trials conducted with pregnant and lactating women (WMD 6.61 µg/L; 95% CI 6.00 to 7.21 µg/L; p < 0.001). Therefore, vitamin A supplementation alone may reduce the risk of anemia, by improving hemoglobin and ferritin levels in individuals with low serum retinol levels.

Adiposity, inflammation and fat-soluble vitamins in adolescents.

OBJECTIVE: Evaluate the association between inflammatory process, adiposity, and vitamins A, D, and E in adolescents, according to gender. METHODS: Cross-sectional study with adolescents aged 12-19 years old of both genders attending public schools in Recife. A questionnaire was used to collect data on socioeconomic level, lifestyle, and food intake of adolescents. Then, an anthropometric evaluation and a blood sampling were performed to analyze serum concentrations of α-1-acid glycoprotein, retinol, ß-carotene, α-tocopherol, and 25-hydroxy-vitamin D. RESULTS: The levels of α-1-acid glycoprotein were higher for abdominal obesity in both genders. Male adolescents with insufficient serum α-tocopherol levels had low levels of α-1-acid glycoprotein (p=0.03) and an increased risk of 25-hydroxy-vitamin D and ß-carotene deficiency in relation to total and abdominal fat; female adolescents had an increased risk of insufficient ß-carotene with abdominal obesity (PR: 1.33; 95% CI: 1.2-1.5). CONCLUSION: Abdominal adiposity implies a higher risk of inflammation and causes different changes to the levels of fat-soluble vitamins according to gender.

Predictors of vitamin A status among pregnant women in Western Brazilian Amazon.

Determining the predictors of serum retinol at mid-pregnancy is relevant for planning interventions aimed at improving vitamin A status of pregnant women and their offspring. This prospective study assessed predictors of serum retinol at the beginning of the third trimester of pregnancy. We enrolled 442 pregnant women living in the urban area of Cruzeiro do Sul, Western Brazilian Amazon. Demographic, socio-economic, environmental and clinical characteristics as well as obstetric history, anthropometric, dietary and biochemical data, including serum retinol, were gathered between 16 and 20 gestational weeks. Serum retinol also measured at the beginning of the third trimester of pregnancy (approximately 28 gestational weeks) was the outcome of interest. Multiple linear regression models were used to evaluate associations with the outcome. Overall, the following variables explained serum retinol at the beginning of the third trimester of pregnancy in the adjusted model (R 2 = 11·1 %): seasonality (winter season - November to April; ß=0·134; 95 % CI 0·063, 0·206), weekly consumption of Amazonian fruits (ß=0·087; 95 % CI 0·012, 0·162) and retinol concentrations between 16 and 20 gestational weeks (ß=0·045; 95 % CI 0·016, 0·074) were positively associated, whereas having a smoker in the house was negatively associated (ß=-0·087; 95 % CI: -0·166, -0·009). Consumption of pro-vitamin A-rich fruits by pregnant women should be encouraged. Passive smoking may play a role in decreasing vitamin A status as a proxy of smoking exposure during pregnancy.

[Association between food insecurity and hemoglobin and retinol levels in children treated in the Brazilian Unified National Health System in the city of Rio de Janeiro, Brazil]. / Associação entre insegurança alimentar e níveis de hemoglobina e retinol em crianças assistidas pelo Sistema Único de Saúde no Município do Rio de Janeiro, Brasil.

This study analyzed the association between food insecurity and hemoglobin and retinol levels in children 6 to 59 months of age. This was a cross-sectional study in 2014 with a representative sample of children in this age bracket treated at basic health units in the city of Rio de Janeiro, Brazil. Analysis of food insecurity levels used the Brazilian Food Insecurity Scale, and venipuncture was performed for measurement of serum hemoglobin and retinol levels. The association between variables used quantile regression models. Of all the children in the sample, 40.3% presented food insecurity, and the prevalence rates for anemia and vitamin A deficiency were 13.7% and 13%, respectively. The study's results revealed a statistically significant inverse association between mild food insecurity and retinol levels. For the other levels of food insecurity (moderate and severe), the results also suggest an inverse association for hemoglobin, and for retinol levels the point estimates appear smaller in children with severe food insecurity, but these estimates were not statistically significant. These results suggest that food insecurity may be associated with micronutrient deficiencies in children under 5 years.

Neste trabalho foi analisada a associação entre insegurança alimentar e níveis de hemoglobina e retinol em crianças de 6 a 59 meses de idade. Trata-se de um estudo seccional, realizado em 2014, com amostra representativa da população de crianças nessa faixa etária, atendidas em unidades básicas de saúde do Município do Rio de Janeiro, Brasil. Para a análise dos níveis de insegurança alimentar foi utilizada a Escala Brasileira de Insegurança Alimentar e, para a determinação de hemoglobina e de retinol sérico, foi realizada a punção venosa. A associação entre as variáveis foi avaliada por intermédio de modelos de regressão quantílica. Do total de crianças estudadas, 40,3% apresentavam insegurança alimentar e as prevalências de anemia e de deficiência de vitamina A foram 13,7% e 13%, respectivamente. Os resultados do estudo revelaram associação inversa, estatisticamente significativa, entre insegurança alimentar leve e níveis de retinol. Para os demais níveis de insegurança alimentar (moderada e grave), os resultados também sugerem a presença de associação inversa para hemoglobina e, quanto aos níveis de retinol, as estimativas pontuais parecem menores em crianças com insegurança alimentar grave, entretanto, estas estimativas não foram estatisticamente significativas. Esses resultados sugerem que a insegurança alimentar pode estar associada com carências de micronutrientes em crianças menores de 5 anos.

En este estudio se analizó la asociación entre la inseguridad alimentaria y los niveles de hemoglobina y retinol en niños de 6 a 59 meses de edad. Se trata de un estudio seccional, realizado en 2014, con una muestra representativa de la población de niños en esta franja etaria, atendida en unidades básicas de salud del Municipio de Río de Janeiro, Brasil. Para el análisis de los niveles de inseguridad alimentaria se utilizó la Escala Brasileña de Inseguridad Alimentaria y, para la determinación de hemoglobina y de retinol sérico, se realizó una punción venosa. La asociación entre las variables se evaluó a través de modelos de regresión cuantílica. Del total de niños estudiados, un 40,3% presentaban inseguridad alimentaria y las prevalencias de anemia y de deficiencia de vitamina A fueron 13,7% y 13%, respectivamente. Los resultados del estudio revelaron una asociación inversa, estadísticamente significativa, entre inseguridad alimentaria leve y niveles de retinol. Para los demás niveles de inseguridad alimentaria (moderada y grave), los resultados también sugieren la presencia de una asociación inversa para la hemoglobina, y, en cuanto a los niveles de retinol, las estimaciones puntuales parecen menores en niños con inseguridad alimentaria grave, sin embargo, estas estimaciones no fueron estadísticamente significativas. Estos resultados sugieren que la inseguridad alimentaria puede estar asociada con carencias de micronutrientes en niños menores de 5 años.

[Factors associated with concentrations of hemoglobin in preschoolers]. / Factores asociados a las concentraciones de hemoglobina en preescolares.

This study sought to identify the association between the concentration of hemoglobin and socio-environmental, maternal, biological-nutritional and health condition characteristics in preschool children; as well as the serum concentrations of zinc and retinol. It involved a cross-sectional study with 335 individuals, a representative sample of children enrolled in child day care centers in the city of Campina Grande, Paraíba. In the 294 children studied, the adjusted model showed lower concentrations of hemoglobin when the house was not made of bricks; there was no sewerage system; no public garbage collection; no treatment of drinking water; maternal difficulties for reading, writing and making calculations; age between 9 - 24 months; weight/age < - 2 score Z and health problems in the last 15 days, as well as in cases of lower serum concentrations of zinc and retinol. The multicausality of lower hemoglobin levels included socio-environmental conditions and child-maternal characteristics that reinforce the importance of measures that prioritize the younger children of mothers with lower education levels and prejudiced in weight, health and nutritional status of other important micronutrients for growth.

El presente estudio buscó identificar en niños preescolares la asociación de las concentraciones de hemoglobina con características socio-ambientales, maternas, biológico-nutricionales y las condiciones de salud; así como con las concentraciones séricas de zinc y retinol. Estudio transversal con muestra de 335 individuos, representativa de los niños de jardines infantiles del municipio de Campina Grande, Paraíba. En los 294 niños estudiados, el modelo ajustado mostró menores concentraciones de hemoglobina en casos de tipo de casa diferente de ladrillo; ausencia de red de escoto; colecta no pública de la basura; no tratamiento del agua para beber; dificultades maternas para leer, escribir o hacer cuentas; edad entre 9-24 meses; peso/edad < - 2 escore Z y problemas de salud en los últimos 15 días, bien como en casos de bajas concentraciones séricas de zinc y retinol. La multicausalidad de concentraciones inferiores de hemoglobina comprendió condiciones socio-ambientales y características materno-infantiles que refuerzan la importancia de medidas que prioricen los niños de menor edad, de madres con menor nivel educacional y con prejuicios en su peso, estado de salud y condición nutricional de otros micronutrientes importantes en el crecimiento.