Table 2.

Risk of colorectal cancer within quintiles of plasma 25(OH)D and 1,25(OH)2D among women in the NHS, 1989–2000

Quintile25(OH)D (ng/mL)
1,25(OH)2D (pg/mL)
Medians*
Cases/controlsORMultivariate OR (95% CI)§Medians*
Cases/controlsORMultivariate OR (95% CI)§
Lab 1Lab 2Lab 1Lab 2
114.917.453/771.001.0024.618.734/771.001.00
219.624.847/790.870.93 (0.53–1.63)29.424.242/781.241.45 (0.78–2.69)
324.129.635/750.700.79 (0.44–1.40)33.229.833/761.010.93 (0.48–1.78)
427.934.529/770.520.58 (0.31–1.07)36.833.838/761.171.21 (0.64–2.26)
535.344.529/750.530.53 (0.27–1.04)43.742.346/751.461.77 (0.93–3.36)
P for trend0.010.020.650.51
  • * Median 25(OH)D and 1,25(OH)2D values per quintile. Lab 1 values are from blood samples assayed in 2000. Lab 2 values are from blood samples assayed in 2003.

  • No. cases/controls per quintile. Controls were matched to cases on year of birth and month of blood draw.

  • ORs from conditional logistic regression analyses without any covariates in the model.

  • § ORs and 95% CIs from conditional logistic regression analyses with adjustment for the following covariates: body mass index; physical activity; pack-years of smoking; menopausal status; use of HRT; duration of aspirin use; family history of colorectal cancer; and daily intakes of calcium folate, methionine, retinol, red meat, and alcohol.

  • P in test of linear trend in risk over continuous values of 25(OH)D and 1,25(OH)2D.