title: Vitamin D status and associated metabolic risk factors among North Korean refugees in South Korea: a cross-sectional study.
abstract: OBJECTIVE
  Vitamin D deficiency is now recognised as a common health problem associated with various chronic diseases; however, it has not been fully elucidated among the minority groups. Here, we aimed to investigate the prevalence of vitamin D deficiency and its associated metabolic risk factors among North Korean refugees living in South Korea.
  
  
  METHODS
  Cross-sectional analysis from the longitudinal cohort, the North Korean refugee health in South Korea (NORNS) study.
  
  
  METHODS
  A total of 386 North Korean refugees aged ≥30 years, who measured serum 25-hydroxy vitamin D (25(OH)D) level.
  
  
  RESULTS
  The prevalence of vitamin D deficiency (25(OH)D <20 ng/mL) was 87% and no participants had an adequate vitamin D level (25(OH)D ≥30 ng/mL). Underweight participants (body mass index (BMI) <18 kg/m(2)) had significantly lower 25(OH)D levels than individuals with normal BMI (≥18.5 and<23 kg/m(2)). In the multivariate logistic regression analysis, the lowest 25(OH)D level (<10 ng/mL) was significantly associated with metabolic syndrome (OR, 6.37, 95% CI 1.34 to 30.3), high triglyceride (OR, 6.71, 95% CI 1.75 to 25.7), and low high-density lipoprotein (OR, 5.98, 95% CI 1.54 to 23.2) compared with 25(OH)D levels ≥20 ng/mL after adjusting for age, sex, season, length of residence in South Korea, physical activity and BMI.
  
  
  CONCLUSIONS
  Vitamin D deficiency is very common among North Korean refugees in South Korea. Despite their lower BMI, vitamin D deficiency was associated with metabolic syndrome in this population.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Kyeong Jin
authors.initials: KJ
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Hallym University Kangdong Sacred Heart Hospital, Seoul, Republic of Korea.
authors.forename: Yoon Jung
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sun Hwa
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: An
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Yoo
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Hee Young
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Ji A
authors.initials: JA
authors.lastname: Seo
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sin Gon
authors.initials: SG
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Nan Hee
authors.initials: NH
authors.lastname: Kim
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Kyung Mook
authors.initials: KM
authors.lastname: Choi
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sei Hyun
authors.initials: SH
authors.lastname: Baik
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Dong Seop
authors.initials: DS
authors.lastname: Choi
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Nam Hoon
authors.initials: NH
authors.lastname: Kim
mesh_terms: D000328:Adult; D044466:Asian People; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D056911:Democratic People's Republic of Korea / Q000208:ethnology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D024821:Metabolic Syndrome / Q000453:epidemiology*; D008875:Middle Aged; D015999:Multivariate Analysis; D009749:Nutrition Surveys; D012036:Refugees / Q000706:statistics & numerical data*; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000453:epidemiology*
chemical_list: D014280:Triglycerides; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Metabolic syndrome; North Korean refugees; Obesity; Vitamin D deficiency; vitamin D