title: Hypovitaminosis D in adults with inflammatory bowel disease: potential role of ethnicity.
abstract: BACKGROUND
  Although vitamin D deficiency occurs in inflammatory bowel disease (IBD), it is currently unclear to what extent ethnicity affects vitamin D levels. Our aim was therefore to determine the ethnic variation in serum 25-hydroxyvitamin D status and its association with disease severity in adults with IBD.
  
  
  METHODS
  We conducted a prospective cohort study in ambulatory care IBD patients. Clinical disease severity was assessed through validated questionnaires. Serum 25-hydroxyvitamin D levels were used for vitamin D status. C-reactive protein (CRP), ferritin and hemoglobin (Hgb) levels were correlated with serum 25-hydroxyvitamin D levels.
  
  
  RESULTS
  Sixty ulcerative colitis (UC) and forty Crohn's disease (CD) patients were enrolled comprising 65 % Caucasians and 29 % South Asians. However, South Asians had consistently lower average serum 25-hydroxyvitamin D levels (All 44.8 ± 18.1 nmol/L, UC 48.2 ± 18.3 nmol/L, CD 24.3 ± 13.3 nmol/L). Hypovitaminosis D was found in 39 % of All, 36.7 % of UC and 42.5 % of CD patients. A significantly higher proportion of South Asians were vitamin D deficient when compared to Caucasians in All and CD groups (58.6 % vs. 30.8 %, p = 0.01 and 85.7 % vs. 32.3 %, p < 0.01, respectively).
  
  
  CONCLUSIONS
  A significantly higher percentage of South Asians had hypovitaminosis D when compared to Caucasians. Disease severity trended towards an inverse relationship with vitamin D status in all South Asian and Caucasian CD patients, although most patients in this study had only mild to moderate disease. We suggest that vitamin D supplementation should be considered in all adult IBD patients.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Gordon and Leslie Diamond Health Care Centre, University of British Columbia, 5th Floor, 2775 Laurel St, Vancouver, BC, V5Z 1M9, Canada. nfu@interchange.ubc.ca
authors.forename: Yi-Tzu Nancy
authors.initials: YT
authors.lastname: Fu
authors.forename: Nazira
authors.initials: N
authors.lastname: Chatur
authors.forename: Cindy
authors.initials: C
authors.lastname: Cheong-Lee
authors.forename: Baljinder
authors.initials: B
authors.lastname: Salh
mesh_terms: D000328:Adult; D044466:Asian People; D003093:Colitis, Ulcerative / Q000150:complications / Q000208:ethnology*; D003424:Crohn Disease / Q000150:complications / Q000208:ethnology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index; D014808:Vitamin D Deficiency / Q000208:ethnology* / Q000209:etiology; D044465:White People