Table 2.

Multivariable-adjusted associations of serum 25(OH)D concentrations and prostate cancer risk in the PCPT, by prostate cancer grade and treatment arm

All cancerGleason 2–6Gleason 7Gleason 8–10
Case/controlORa (95% CI)Case/controlORa (95% CI)Case/controlORa (95% CI)Case/controlORa (95% CI)
Placebo
 Q1b193/233Ref136/233Ref33/233Ref16/233Ref
 Q2b232/2531.01 (0.78–1.33)173/2531.05 (0.78–1.40)40/2531.06 (0.65–1.77)9/2530.54 (0.23–1.27)
 Q3b276/2311.32 (1.01–1.73)204/2311.35 (1.01–1.80)48/2311.40 (0.87–2.31)12/2310.81 (0.37–1.78)
 Q4b286/2541.18 (0.91–1.53)219/2541.25 (0.94–1.66)47/2541.19 (0.73–1.97)8/2540.50 (0.20–1.22)
Ptrend0.080.050.330.22
Finasteride
 Q1b165/188Ref89/188Ref46/188Ref24/188Ref
 Q2b162/1670.91 (0.66–1.26)193/1670.96 (0.66–1.40)40/1670.82 (0.51–1.34)21/1670.85 (0.45–1.60)
 Q3b173/1880.78 (0.57–1.06)100/1880.83 (0.58–1.21)43/1880.70 (0.44–1.13)20/1880.63 (0.33–1.21)
 Q4b208/1681.02 (0.74–1.39)127/1681.16 (0.81–1.67)57/1681.01 (0.64–1.59)17/1680.57 (0.29–1.12)
Ptrend0.900.520.940.07
Combined
 Q1b358/421Ref225/421Ref79/421Ref40/421Ref
 Q2b394/4200.97 (0.79–1.18)266/4201.01 (0.81–1.28)80/4200.93 (0.66–1.31)30/4200.73 (0.44–1.21)
 Q3b449/4191.07 (0.87–1.30)304/4191.13 (0.90–1.42)91/4191.01 (0.72–1.42)32/4190.75 (0.45–1.23)
 Q4b494/4221.10 (0.90–1.35)346/4221.21 (0.97–1.52)104/4221.09 (0.78–1.52)25/4220.55 (0.32–0.94)
Ptrend0.200.060.480.04
Pinteractionc0.580.770.840.50

NOTE: Vitamin D standardized for month of blood draw before dividing into quartiles based on distribution in controls.

  • aORs adjusted for age (continuous) and race (White, African American, other race); ORs for combined treatment arms also adjusted for treatment (finasteride, placebo).

  • bQuartile cutoff points of adjusted values: 44.7, 56.8, and 71.2 nmol/L.

  • cInteraction tested as the cross-product of 25(OH)D concentration rank (lowest to highest quartile) and an indicator for treatment (finasteride, placebo).