title: Genetic and environmental factors associated with vitamin B12 status in Amazonian children.
abstract: OBJECTIVE
  To evaluate the prevalence of vitamin B12 deficiency and factors associated with vitamin B12 status in Amazonian children.
  
  
  METHODS
  Genetic risk score (GRS), socio-economic and nutritional status, and morbidity data were the independent variables used in multiple linear regression models to evaluate factors associated with vitamin B12 status in a population-based cross-sectional study. GRS was created by summing a number of known risk alleles for low serum vitamin B12.
  
  
  METHODS
  Acrelândia, western Brazilian Amazon.
  
  
  METHODS
  Children (n 988) aged <10 years.
  
  
  RESULTS
  Overall prevalence of vitamin B12 deficiency (<150 pmol/l) was 4·2 (95 % CI 3·0, 5·6) % and was highest in children aged <24 months: 13·6 (95 % CI % 8·8, 19·7) %. For children <24 months, wealth index (β=0·017, P=0·030) and animal protein intake (β=0·219, P=0·003) were positively associated with vitamin B12 status. GRS (β=-0·114, P<0·001) and serum homocysteine (β=-0·049, P<0·001) were negatively associated. Among children aged ≥24 months, vitamin B12 status was positively associated with wealth index (β=0·012, P<0·001), height-for-age Z-score (β=0·024, P=0·033) and serum vitamin A (β=0·089, P<0·001). Age≥60 months (β=-0·118, P<0·001), GRS (β=-0·048, P<0·001), maternal schooling <5 years (β=-0·083, P<0·001), low intake of animal-derived foods (β=-0·050, P=0·030), serum homocysteine (β=-0·053, P<0·001), serum folate ≥23·6 nmol/l (β=-0·055, P=0·012) and geohelminth infection (β=-0·141, P=0·017) were negatively associated with vitamin B12 status.
  
  
  CONCLUSIONS
  GRS, poverty, low intake of animal-derived foods, geohelminth infection, vitamin A and folate status were important factors associated with vitamin B12 status of children in our study.
authors.affiliation: 1Department of Nutrition,School of Public Health,University of São Paulo,Av. Dr Arnaldo 715,01246-904 São Paulo,Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Cobayashi
authors.affiliation: 2Department of Preventive Medicine,Federal University of São Paulo,São Paulo,Brazil.
authors.forename: Luciana Yuki
authors.initials: LY
authors.lastname: Tomita
authors.affiliation: 1Department of Nutrition,School of Public Health,University of São Paulo,Av. Dr Arnaldo 715,01246-904 São Paulo,Brazil.
authors.forename: Rosangela Aparecida
authors.initials: RA
authors.lastname: Augusto
authors.affiliation: 3Department of Psychobiology,Federal University of São Paulo,São Paulo,Brazil.
authors.forename: Vania
authors.initials: V
authors.lastname: D'Almeida
authors.affiliation: 1Department of Nutrition,School of Public Health,University of São Paulo,Av. Dr Arnaldo 715,01246-904 São Paulo,Brazil.
authors.forename: Marly Augusto
authors.initials: MA
authors.lastname: Cardoso
mesh_terms: D000483:Alleles; D015992:Body Mass Index; D001835:Body Weight; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005492:Folic Acid / Q000008:administration & dosage / Q000097:blood; D059647:Gene-Environment Interaction; D060005:Genotyping Techniques; D006130:Growth Disorders / Q000453:epidemiology* / Q000235:genetics; D006710:Homocysteine / Q000097:blood; D006801:Humans; D007223:Infant; D016014:Linear Models; D015596:Nutrition Assessment; D009752:Nutritional Status; D050177:Overweight / Q000453:epidemiology* / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D015995:Prevalence; D012307:Risk Factors; D012959:Socioeconomic Factors; D014801:Vitamin A / Q000008:administration & dosage / Q000097:blood; D014805:Vitamin B 12 / Q000008:administration & dosage / Q000097:blood*; D014806:Vitamin B 12 Deficiency / Q000453:epidemiology* / Q000235:genetics*
chemical_list: D006710:Homocysteine; D014801:Vitamin A; D005492:Folic Acid; D014805:Vitamin B 12
keywords: 10-Methylenetetrahydrofolate reductase; 5; Child health; Fucosyltransferase 2 protein; Genetic polymorphism; Nutritional status; Vitamin B12