ABSTRACT
Objective: To estimate the national and regional population attributable fraction (PAF) and potential number of preventable anemia cases for three nutritional risk factors (iron, red blood cell folate [RBCF], and vitamin B12 deficiencies) among women of childbearing age in Belize. Methods: A national probability-based household and micronutrient survey capturing sociodemographic and health information was conducted among 937 nonpregnant Belizean women aged 15-49 years. Blood samples were collected to determine hemoglobin, ferritin, alpha-1-glycoprotein (AGP), RBCF, and vitamin B12 status. All analyses used sample weights and design variables to reflect a complex sample survey. Logistic regression was used to determine adjusted prevalence risk (aPR) ratios, which were then used to estimate national and regional PAF for anemia. Results: The overall prevalence of anemia (hemoglobin <12 g/dL) was 21.2% (95% CI [18.7, 25.3]). The prevalence of anemia was significantly greater among women with iron deficiency (59.5%, 95% CI [48.7, 69.5]) compared to women without iron deficiency (15.2%, 95% CI [12.2, 18.3]; aPR 3.9, 95% CI [2.9, 5.1]). The three nutritional deficiencies examined contributed to 34.6% (95% CI [22.1, 47.1]) of the anemia cases. If all these nutritional deficiencies could be eliminated, then an estimated 5 953 (95% CI [3 807, 8 114]) anemia cases could be prevented. Conclusions: This study suggests that among women of child-bearing age in Belize, anemia cases might be reduced by a third if three modifiable nutritional risk factors (iron, RBCF, and vitamin B12 deficiencies) could be eliminated. Fortification is one potential strategy to improve nutritional status and reduce the burden of anemia in this population.
ABSTRACT
[ABSTRACT]. Objective. To estimate the national and regional population attributable fraction (PAF) and potential number of preventable anemia cases for three nutritional risk factors (iron, red blood cell folate [RBCF], and vitamin B12 deficiencies) among women of childbearing age in Belize. Methods. A national probability-based household and micronutrient survey capturing sociodemographic and health information was conducted among 937 nonpregnant Belizean women aged 15–49 years. Blood samples were collected to determine hemoglobin, ferritin, alpha-1-glycoprotein (AGP), RBCF, and vitamin B12 status. All analyses used sample weights and design variables to reflect a complex sample survey. Logistic regression was used to determine adjusted prevalence risk (aPR) ratios, which were then used to estimate national and regional PAF for anemia. Results. The overall prevalence of anemia (hemoglobin <12 g/dL) was 21.2% (95% CI [18.7, 25.3]). The prevalence of anemia was significantly greater among women with iron deficiency (59.5%, 95% CI [48.7, 69.5]) compared to women without iron deficiency (15.2%, 95% CI [12.2, 18.3]; aPR 3.9, 95% CI [2.9, 5.1]). The three nutritional deficiencies examined contributed to 34.6% (95% CI [22.1, 47.1]) of the anemia cases. If all these nutritional deficiencies could be eliminated, then an estimated 5 953 (95% CI [3 807, 8 114]) anemia cases could be prevented. Conclusions. This study suggests that among women of child-bearing age in Belize, anemia cases might be reduced by a third if three modifiable nutritional risk factors (iron, RBCF, and vitamin B12 deficiencies) could be eliminated. Fortification is one potential strategy to improve nutritional status and reduce the burden of anemia in this population.
[RESUMEN]. Objetivo. Calcular la fracción atribuible poblacional a nivel nacional y regional y el número de casos de anemia que podrían prevenirse para tres factores de riesgo nutricional (deficiencia de hierro, folato eritrocitario y vitamina B12) en las mujeres en edad reproductiva en Belice. Metodología. Se llevó a cabo una encuesta probabilística nacional sobre características de los hogares y micronutrientes en la que se recopiló información sociodemográfica y de salud de 937 mujeres beliceñas no embarazadas de entre 15 y 49 años. Se extrajeron muestras de sangre para determinar los niveles de hemoglobina, ferritina, alfa–1–glucoproteína, folato eritrocitario y vitamina B12. En todos los análisis se emplearon ponderaciones muestrales y variables calculadas para tener en cuenta que se trataba de una encuesta con una muestra compleja. Se estimaron mediante regresión logística las razones de riesgos de prevalencia ajustados, que posteriormente se utilizaron para calcular la fracción atribuible poblacional con respecto a la anemia a nivel nacional y regional. Resultados. La prevalencia global de la anemia (hemoglobina <12 g/dl) fue del 21,2% (IC del 95%: 18,7– 25,3). La prevalencia de la anemia fue significativamente mayor en las mujeres con ferropenia (59,5%, IC del 95%: 48,7–69,5) que en las que no tenían ferropenia (15,2%, IC del 95%: 12,2, 18,3); razón de riesgos de prevalencia ajustados = 3.9, IC del 95%; 2,9–5,1). Las tres deficiencias nutricionales examinadas explicaban al 34,6% (IC del 95%: 22,1–47,1) de los casos de anemia. Se estima que si pudieran eliminarse todas estas deficiencias nutricionales, se prevendrían unos 5953 (IC del 95%: 3807–8114) casos de anemia. Conclusiones. Los resultados de este estudio sugieren que los casos de anemia en las mujeres en edad reproductiva de Belice podrían reducirse en un tercio si se pudieran eliminar tres factores de riesgo nutricionales modificables (deficiencias de hierro, folato eritrocitario y vitamina B12). Una posible estrategia para mejorar el estado nutricional y reducir la carga de la anemia en este grupo poblacional es en el enriquecimiento de los alimentos con suplementos.
[RESUMO]. Objetivo. Estimar a fração atribuível populacional (FAP) nacional e regional e o potencial número de casos preveníveis de anemia para três fatores de risco nutricionais (deficiência de ferro, ácido fólico eritrocitário e vitamina B12) entre mulheres em idade fértil em Belize. Métodos. Realizou-se um inquérito probabilístico domiciliar nacional sobre micronutrientes, que coletou informações sociodemográficas e de saúde de 937 mulheres belizenhas não grávidas com idade entre 15 e 49 anos. Coletaram-se amostras de sangue para dosagem de hemoglobina, ferritina, alfa-1-glicoproteína (AGP), ácido fólico eritrocitário e vitamina B12. Todas as análises usaram variáveis de delineamento e ponderações amostrais para refletir um inquérito amostral complexo. Aplicou-se regressão logística para determinar razões ajustadas de risco de prevalência (RPa), que foram usadas para estimar a FAP nacional e regional para anemia. Resultados. A prevalência geral de anemia (hemoglobina <12 g/dL) foi de 21,2% (IC 95% [18,7–25,3]). A prevalência de anemia foi significativamente maior em mulheres com deficiência de ferro (59,5%, IC 95% [48,7–69,5]) que em mulheres sem deficiência de ferro (15,2%, IC 95% [12,2–18,3]); RPa 3,9, IC 95% [2,9– 5,1]). As três deficiências nutricionais analisadas contribuíram para 34,6% (IC 95% [22,1–47,1]) dos casos de anemia. Caso se eliminassem todas essas deficiências nutricionais, seria possível evitar cerca de 5.953 (IC 95% [3.807–8.114]) casos de anemia. Conclusões. Este estudo sugere que, nas mulheres belizenhas em idade fértil, os casos de anemia poderiam ser reduzidos em um terço caso fosse possível eliminar três fatores de risco nutricionais modificáveis (deficiência de ferro, ácido fólico eritrocitário e vitamina B12). A fortificação é uma possível estratégia para melhorar o estado nutricional e reduzir a carga de anemia nessa população.
Subject(s)
Anemia , Risk Factors , Women's Health , Anemia, Iron-Deficiency , Folic Acid , Vitamin B 12 Deficiency , Belize , Risk Factors , Women's Health , Anemia, Iron-Deficiency , Folic Acid , Vitamin B 12 Deficiency , Belize , Risk Factors , Women's Health , Anemia, Iron-Deficiency , Vitamin B 12 DeficiencyABSTRACT
BACKGROUND/OBJECTIVES: Obesity and maternal folate deficiency are associated with increased risk for neural tube defects (NTDs). Limited knowledge exists on the impact of folate status or obesity on DNA methylation of genes related to NTD risk and folate metabolism. SUBJECTS/METHODS: Women (18-35y) with normal weight (NW; BMI 18.5-24.9kg/m2; n=12) and obesity (OB; BMI >30kg/m2; n=6) were provided FA (800µg/d) for 8-weeks. Serum folate concentration and changes in DNA methylation across 2098 CpG sites in 91 genes related to NTD risk and folate metabolism were examined. RESULTS: Serum folate concentration increased in both groups following FA supplementation, but OB maintained a relative lower concentration (NW; 38.36±2.50-71.41±3.02nmol/L and OB; 27.12±3.09-56.85±3.90nmol/L). Methylation of 56 and 99 CpG sites changed in response to supplementation in NW and OB, respectively, and majority of these sites decreased in methylation in both groups. Only 4 CpG sites responded to supplementation in both groups. Gene ontology analysis revealed a response to supplementation in 61 biological processes (BPs) from the selected genes. Five of the 61 BPs were identified only in NW, including neural tube closure, while 13 of the 61 BPs were enriched only in OB, including folate metabolism, vitamin B12 metabolism and methylation related processes. CONCLUSIONS: Changes in DNA methylation in genes related to NTD risk and folate metabolism in response to FA supplementation were different in NW and OB. Increased NTD risk and abnormal folate metabolism in obesity may be due to a distinctive epigenetic response to folate status in these genes.
Subject(s)
DNA Methylation/drug effects , Dietary Supplements , Folic Acid/administration & dosage , Obesity/genetics , Adolescent , Adult , Female , Folic Acid/blood , Humans , Obesity/blood , Pilot Projects , Young AdultABSTRACT
Background: Folate deficiency, vitamin B-12 deficiency, and anemia can have adverse effects on birth outcomes. Also, low vitamin B-12 reduces the formation of metabolically active folate.Objectives: We sought to establish the baseline prevalence of and factors associated with folate deficiency and insufficiency, vitamin B-12 deficiency, and anemia among women of childbearing age (WCBA) in Belize.Methods: In 2011, a national probability-based survey was completed among Belizean nonpregnant WCBA aged 15-49 y. Blood samples for determination of hemoglobin, folate (RBC and serum), and vitamin B-12 (plasma) and sociodemographic and health information were collected from 937 women. RBC and serum folate concentrations were measured by microbiologic assay (MBA). Folate status was defined based on both the WHO-recommended radioproteinbinding assay and the assay adjusted for the MBA.Results: The national prevalence estimates for folate deficiency in WCBA, based on serum and RBC folate concentrations by using the assay-matched cutoffs, were 11.0% (95% CI: 8.6%, 14.0%) and 35.1% (95% CI: 31.3%, 39.2%), respectively. By using the assay-matched compared with the WHO-recommended cutoffs, a substantially higher prevalence of folate deficiency was observed based on serum (6.9% absolute difference) and RBC folate (28.9% absolute difference) concentrations. The prevalence for RBC folate insufficiency was 48.9% (95% CI: 44.8%, 53.1%). Prevalence estimates for vitamin B-12 deficiency and marginal deficiency and anemia were 17.2% (95% CI: 14.2%, 20.6%), 33.2% (95% CI: 29.6%, 37.1%), and 22.7% (95% CI: 19.5%, 26.2%), respectively. The adjusted geometric means of the RBC folate concentration increased significantly (P-trend < 0.001) in WCBA who had normal vitamin B-12 status relative to WCBA who were vitamin B-12 deficient.Conclusions: In Belize, the prevalence of folate and vitamin B-12 deficiencies continues to be a public health concern among WCBA. Furthermore, low folate status co-occurred with low vitamin B-12 status, underlining the importance of providing adequate vitamin B-12 and folic acid intake through approaches such as mandatory food fortification.
Subject(s)
Folic Acid Deficiency/epidemiology , Folic Acid/blood , Nutritional Status , Vitamin B 12 Deficiency/epidemiology , Vitamin B 12/blood , Vitamin B Complex/blood , Adolescent , Adult , Anemia/blood , Anemia/epidemiology , Belize/epidemiology , Erythrocytes/metabolism , Female , Folic Acid Deficiency/blood , Folic Acid Deficiency/complications , Hemoglobins/metabolism , Humans , Middle Aged , Nutrition Surveys , Prevalence , Risk Factors , Vitamin B 12 Deficiency/blood , Vitamin B 12 Deficiency/complications , Young AdultABSTRACT
BACKGROUND: Studies have questioned whether the current Recommended Dietary Allowance (RDA) of 2.4 microg vitamin B-12/d is adequate. OBJECTIVE: We examined the association between dietary vitamin B-12 intake and biomarkers of vitamin B-12 status. DESIGN: Dietary vitamin B-12 intake was estimated, and biomarkers of vitamin B-12 status were measured, in healthy men and women (n = 299; age range: 18-50 y) who were recruited from a Florida community. The National Cancer Institute Diet History Questionnaire was used. Plasma cobalamin, total transcobalamin, holo-transcobalamin, methylmalonic acid (MMA), total homocysteine (tHcy), and autoantibodies against intrinsic factor (IF) and Helicobacter pylori were analyzed in blood samples. RESULTS: Antibodies to H. pylori were detected in 12% of subjects (35/299), and negative results for IF antibodies were obtained for all subjects. The intake of vitamin B-12 correlated significantly with cobalamin, holo-transcobalamin, MMA, and tHcy. Subjects were divided into quintiles on the basis of their dietary vitamin B-12 intake (range: 0.42-22.7 microg/d), and biomarkers of vitamin B-12 status were plotted against estimated dietary vitamin B-12 intake. All biomarkers appeared to level off at a daily dietary vitamin B-12 intake between 4.2 and 7.0 microg. CONCLUSION: In persons with normal absorption, our data indicate that an intake of 4-7 microg vitamin B-12/d is associated with an adequate vitamin B-12 status, which suggests that the current RDA of 2.4 microg vitamin B-12/d might be inadequate for optimal biomarker status even in a healthy population between 18 and 50 y of age.
