title: A Trial of Calcium and Vitamin D for the Prevention of Colorectal Adenomas.
abstract: BACKGROUND
  Epidemiologic and preclinical data suggest that higher intake and serum levels of vitamin D and higher intake of calcium reduce the risk of colorectal neoplasia. To further study the chemopreventive potential of these nutrients, we conducted a randomized, double-blind, placebo-controlled trial of supplementation with vitamin D, calcium, or both for the prevention of colorectal adenomas.
  
  
  METHODS
  We recruited patients with recently diagnosed adenomas and no known colorectal polyps remaining after complete colonoscopy. We randomly assigned 2259 participants to receive daily vitamin D3 (1000 IU), calcium as carbonate (1200 mg), both, or neither in a partial 2×2 factorial design. Women could elect to receive calcium plus random assignment to vitamin D or placebo. Follow-up colonoscopy was anticipated to be performed 3 or 5 years after the baseline examinations, according to the endoscopist's recommendation. The primary end point was adenomas diagnosed in the interval from randomization through the anticipated surveillance colonoscopy.
  
  
  RESULTS
  Participants who were randomly assigned to receive vitamin D had a mean net increase in serum 25-hydroxyvitamin D levels of 7.83 ng per milliliter, relative to participants given placebo. Overall, 43% of participants had one or more adenomas diagnosed during follow-up. The adjusted risk ratios for recurrent adenomas were 0.99 (95% confidence interval [CI], 0.89 to 1.09) with vitamin D versus no vitamin D, 0.95 (95% CI, 0.85 to 1.06) with calcium versus no calcium, and 0.93 (95% CI, 0.80 to 1.08) with both agents versus neither agent. The findings for advanced adenomas were similar. There were few serious adverse events.
  
  
  CONCLUSIONS
  Daily supplementation with vitamin D3 (1000 IU), calcium (1200 mg), or both after removal of colorectal adenomas did not significantly reduce the risk of recurrent colorectal adenomas over a period of 3 to 5 years. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT00153816.).
authors.affiliation: From the Departments of Medicine (J.A.B., D.J.R., R.R.) and Epidemiology (J.A.B., E.L.B., L.A.M., J.R.R.), Geisel School of Medicine at Dartmouth, Hanover, and Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon (D.J.R., R.R.) - both in New Hampshire; the Departments of Medicine (J.A.B., R.S.S.) and Biostatistics (A.I.), University of North Carolina at Chapel Hill, Chapel Hill; the Department of Pathology, Fairview Southdale Hospital, Edina (D.C.S.), and the Division of Environmental Health Sciences, University of Minnesota School of Public Health (T.R.C.), Minnesota Gastroenterology (A.S.K.), Department of Medicine, University of Minnesota (A.S.), and Minneapolis Veterans Affairs (VA) Medical Center (A.S.), Minneapolis - all in Minnesota; the Department of Epidemiology, Rollins School of Public Health, Emory University and Winship Cancer Institute, Emory University, Atlanta (R.M.B., M.G.); the Department of Mathematics and Statistics, University of Vermont, Burlington (B.F.C.), and VA Outcomes Group, White River Junction (D.J.R.) - both in Vermont; the Department of Medicine, University of Colorado School of Medicine, Denver (D.J.A.); the Departments of Quantitative Health Sciences (G.J.B.) and Gastroenterology and Hepatology (C.A.B.), Cleveland Clinic, Cleveland; the Department of Gastroenterology, Hepatology, and Nutrition, University of Texas M.D. Anderson Cancer Center, Houston (R.S.B.); Puerto Rico Cancer Center, Medical Sciences Campus, University of Puerto Rico, San Juan (M.C.-C.); the Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles (J.C.F.); Consultants in Gastroenterology, West Columbia, SC (M.E.S.); and the Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City (R.W.S.).
authors.forename: John A
authors.initials: JA
authors.lastname: Baron
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Barry
authors.forename: Leila A
authors.initials: LA
authors.lastname: Mott
authors.forename: Judy R
authors.initials: JR
authors.lastname: Rees
authors.forename: Robert S
authors.initials: RS
authors.lastname: Sandler
authors.forename: Dale C
authors.initials: DC
authors.lastname: Snover
authors.forename: Roberd M
authors.initials: RM
authors.lastname: Bostick
authors.forename: Anastasia
authors.initials: A
authors.lastname: Ivanova
authors.forename: Bernard F
authors.initials: BF
authors.lastname: Cole
authors.forename: Dennis J
authors.initials: DJ
authors.lastname: Ahnen
authors.forename: Gerald J
authors.initials: GJ
authors.lastname: Beck
authors.forename: Robert S
authors.initials: RS
authors.lastname: Bresalier
authors.forename: Carol A
authors.initials: CA
authors.lastname: Burke
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Church
authors.forename: Marcia
authors.initials: M
authors.lastname: Cruz-Correa
authors.forename: Jane C
authors.initials: JC
authors.lastname: Figueiredo
authors.forename: Michael
authors.initials: M
authors.lastname: Goodman
authors.forename: Adam S
authors.initials: AS
authors.lastname: Kim
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Robertson
authors.forename: Richard
authors.initials: R
authors.lastname: Rothstein
authors.forename: Aasma
authors.initials: A
authors.lastname: Shaukat
authors.forename: March E
authors.initials: ME
authors.lastname: Seabrook
authors.forename: Robert W
authors.initials: RW
authors.lastname: Summers
mesh_terms: D000236:Adenoma / Q000453:epidemiology / Q000517:prevention & control*; D000368:Aged; D002118:Calcium / Q000009:adverse effects / Q000627:therapeutic use*; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000517:prevention & control*; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012306:Risk; D017211:Treatment Failure; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood / Q000627:therapeutic use*; D014815:Vitamins / Q000627:therapeutic use*
chemical_list: D014815:Vitamins; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium