title: Prevalence of vitamin D insufficiency and associated factors among Canadian Cree: a cross-sectional study.
abstract: OBJECTIVE
  Aboriginal peoples affected by a nutrition transition and living at high latitudes are among the ethnic groups most at risk of vitamin D deficiency. The objectives of this study were to determine the prevalence of meeting predefined cut-off concentrations of vitamin D and to examine associated factors among James Bay Cree aged ≥ 15 years.
  
  
  METHODS
  A cross-sectional study was conducted between the months of May and September from 2005 to 2009. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were determined by radioimmunoassay. Anthropometrics were measured and additional information on socio-demographic characteristics, lifestyle and dietary habits was obtained using questionnaires. A logistic regression model predicting vitamin D insufficiency (<50 nmol/L) included known covariates.
  
  
  RESULTS
  Data were obtained from 944 Cree (406 men (43%); mean age 37.4 years), with an effective participation rate of 49% among women and 41% among men. Mean serum 25(OH)D concentrations (nmol/L) by gender were 52.9 (95% CI 51.4-54.5) in men and 47.5 (95% CI 46.2-48.9) in women, and by age group were 46.0 (95% CI 44.9-48.9) in those 15-39 years and 59.6 (95% CI 57.9-61.4) in those ≥ 40 years of age. Overall, 5.8%, 42.6%, 40.0%, and 11.7% of the participants had 25(OH)D concentrations <30, 30-49.9, 50-74.9 and ≥ 75 nmol/L, respectively. Female gender, obesity, younger age, spring, low fish and milk intake, and low vigorous physical activity predicted vitamin D insufficiency (all p<0.05).
  
  
  CONCLUSIONS
  The vitamin D status in Eastern James Bay Cree is suboptimal with nearly half of the population having insufficient concentrations for optimum bone health.
authors.affiliation: Laval University, Faculty of Medicine, Department of Social and Preventive Medicine. bruno.riverin.1@ulaval.ca.
authors.forename: Bruno
authors.initials: B
authors.lastname: Riverin
authors.forename: Eric
authors.initials: E
authors.lastname: Dewailly
authors.forename: Suzanne
authors.initials: S
authors.lastname: Côté
authors.forename: Louise
authors.initials: L
authors.lastname: Johnson-Down
authors.forename: Suzanne
authors.initials: S
authors.lastname: Morin
authors.forename: Sylvie
authors.initials: S
authors.lastname: Dodin
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002170:Canada / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004032:Diet / Q000208:ethnology; D005260:Female; D006801:Humans; D007198:Indians, North American / Q000706:statistics & numerical data*; D008297:Male; D009765:Obesity / Q000208:ethnology; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution; D011795:Surveys and Questionnaires; D013997:Time Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000208:ethnology*; D055815:Young Adult
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Natives; Vitamin D; prevalence; vitamin D deficiency
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