Table 4.

Supplementation effects on prostate cancer HRs within tertiles of plasma α-tocopherol and γ-tocopherol, SELECT case–cohort study

Plasma tocopherol tertiles
 Median, mg/L9.5012.6517.61
 Cases/subcohort, na529/1,108602/1,059609/1,039Ptrend
Intervention HRb (95% CI)
 α-Tocopherol vs. placebo1.03 (0.68–1.58)1.24 (0.84–1.84)1.10 (0.76–1.59)0.54
 Selenomethionine vs. placebo0.84 (0.55–1.27)1.06 (0.72–1.57)1.26 (0.85–1.88)0.31
 α-Tocopherol and selenomethionine vs. placebo0.97 (0.65–1.45)0.92 (0.62–1.37)1.34 (0.90–2.01)0.39
 Any selenomethionine vs. placebo0.90 (0.63–1.29)1.05 (0.74–1.49)1.38 (0.98–1.95)
 Any α-tocopherol vs. placebo1.03 (0.72–1.48)1.11 (0.78–1.57)1.25 (0.90–1.74)
γ-Tocopherol≤1.32>1.32–≤ 2.23>2.23
 Median, mg/L0.861.732.96
 Cases/subcohort, na597/1,051613/1,031530/1,124
Intervention HRb (95% CI)
 α-Tocopherol vs. placebo0.98 (0.66–1.45)1.14 (0.77–1.68)1.37 (0.93–2.03)0.42
 Selenomethionine vs. placebo1.08 (0.73–1.58)1.03 (0.70–1.52)1.22 (0.80–1.86)0.74
 α-Tocopherol and selenomethionine vs. placebo1.19 (0.80–1.78)1.02 (0.69–1.50)1.22 (0.81–1.83)0.48
 Any selenomethionine vs. placebo1.17 (0.84–1.64)1.02 (0.73–1.43)1.25 (0.86–1.82)
 Any α-tocopherol vs. placebo1.09 (0.77–1.54)1.03 (0.73–1.44)1.29 (0.90–1.83)
  • aThe subcohort contains both cases and non-cases, with overlap between case and subcohort numbers.

  • bHRs and 95% CIs based on proportional hazard regression, stratified by tocopherol tertile and adjusted for PSA (continuous), family history of prostate cancer, BMI (continuous), diabetes at baseline, cholesterol (continuous), and smoking status (current smoker, former smoker, and never smoker) and mutually adjusted for γ-tocopherol or α-tocopherol (continuous). Results are also age- and race-adjusted as a result of all models being stratified by age/race groups before being weighted and combined to generate summary statistics. For each HR, the referent category is placebo arm within that category of plasma tocopherol concentration.