title: Meta-analysis: Serum vitamin D and colorectal adenoma risk.
abstract: OBJECTIVE
  To perform a systematic review and meta-analysis of human studies on the association between serum 25 hydroxyvitamin D (25(OH)D) and incident, sporadic colorectal adenoma (CRA) and CRA recurrence.
  
  
  METHODS
  Relevant studies among humans were identified by systematically searching Ovid Medline, EMBASE, and ISI Web of Knowledge databases and by cross-referencing. Due to the heterogeneity across studies in categorizing serum vitamin D levels, all results were recalculated for an increase of serum 25(OH)D by 20 ng/ml. Summary odds ratios (ORs) were calculated using meta-analysis methods.
  
  
  RESULTS
  Overall, 10 original studies were included. Specific results for incident CRA according to serum 25(OH)D were reported in 8 studies, and for CRA recurrence in 2 studies, respectively. In meta-analyses, summary ORs (95% confidence intervals) regarding incident and recurrent CRA, and both outcomes combined were 0.82 (0.69-0.97), 0.87 (0.56-1.35), and 0.84 (0.72-0.97), respectively, for an increase of 25(OH)D by 20 ng/ml. No publication bias was found.
  
  
  CONCLUSIONS
  Our results support suggestions that serum 25(OH)D levels are inversely associated with CRA risk.
authors.affiliation: Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, Bergheimer Strasse 20, Heidelberg, Germany
authors.forename: Lu
authors.initials: L
authors.lastname: Yin
authors.forename: Norma
authors.initials: N
authors.lastname: Grandi
authors.forename: Elke
authors.initials: E
authors.lastname: Raum
authors.forename: Ulrike
authors.initials: U
authors.lastname: Haug
authors.forename: Volker
authors.initials: V
authors.lastname: Arndt
authors.forename: Hermann
authors.initials: H
authors.lastname: Brenner
mesh_terms: D000236:Adenoma / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control*; D015179:Colorectal Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control*; D006801:Humans; D012008:Recurrence; D012307:Risk Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D