title: The epidemiology of anemia in pediatric inflammatory bowel disease: prevalence and associated factors at diagnosis and follow-up and the impact of exclusive enteral nutrition.
abstract: BACKGROUND
  Anemia is poorly studied in pediatric inflammatory bowel disease. This study explored the epidemiology and associated factors of anemia at diagnosis, after 1 year, and during treatment with exclusive enteral nutrition (EEN).
  
  
  METHODS
  Three cohorts were included: (1) a representative population of newly diagnosed inflammatory bowel disease children (n = 184); (2) patients currently receiving care with data available at diagnosis (n = 179) and after 1 year (n = 139); and (3) 84 children treated with EEN.
  
  
  RESULTS
  At diagnosis, 72% were anemic. Abnormal inflammatory markers were more common in Crohn's disease with severe anemia (severe versus no anemia [%]: raised C-reactive protein; 89% versus 48%; suboptimal albumin; 97% versus 29%; P < 0.002). Anemic children with Crohn's disease had shorter diagnosis delay and lower BMI than nonanemic patients (severe versus mild versus no anemia, median [interquartile range]; diagnosis delay [months]: 3 [3.9] versus 6 [10] versus 8 [18], P < 0.001; BMI z score [SD]: -1.4 [1.4] versus -1.3 [1.5] versus -0.2 [1.4], P = 0.003). Extensive colitis was associated with severe anemia in ulcerative colitis. The proportion of severely anemic patients decreased from 34% to 9% and mild anemia doubled at 1 year. After EEN, severe anemia decreased (32% to 9%; P < 0.001) and the hemoglobin concentration increased by 0.75 g/dL. This was observed only after 8 weeks of treatment. Disease improvement and low hemoglobin at EEN initiation but not weight gain were associated with hemoglobin improvement.
  
  
  CONCLUSIONS
  Anemia is high at diagnosis and follow-up and should receive more attention from the clinical team; however, the focus should remain suppression of inflammatory process in active disease.
authors.affiliation: *Human Nutrition, School of Medicine, College of Medical, Veterinary and Life Sciences, Royal Hospital for Sick Children Glasgow, University of Glasgow, Glasgow, United Kingdom; and †Department of Paediatric Gastroenterology and Nutrition, Royal Hospital for Sick Children Glasgow, National Health Service Greater Glasgow and Clyde, Glasgow, United Kingdom.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Gerasimidis
authors.forename: Andrew
authors.initials: A
authors.lastname: Barclay
authors.forename: Alexandros
authors.initials: A
authors.lastname: Papangelou
authors.forename: Despoina
authors.initials: D
authors.lastname: Missiou
authors.forename: Elaine
authors.initials: E
authors.lastname: Buchanan
authors.forename: Cardigan
authors.initials: C
authors.lastname: Tracey
authors.forename: Rachel
authors.initials: R
authors.lastname: Tayler
authors.forename: Richard K
authors.initials: RK
authors.lastname: Russell
authors.forename: Christine A
authors.initials: CA
authors.lastname: Edwards
authors.forename: Paraic
authors.initials: P
authors.lastname: McGrogan
mesh_terms: D000293:Adolescent; D000740:Anemia / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D015415:Biomarkers / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D003424:Crohn Disease / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D004750:Enteral Nutrition; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D011379:Prognosis
chemical_list: D015415:Biomarkers