Table 6

Risks of prostate cancer, by grade and stage, by quartile of control selenium (μg/dl) distributions

Gleason scoresaStage of cancerb
LowHighEarlyAdvanced
n 97787737
OR (95% CI)c
 Q11.001.001.001.00
 Q20.71 (0.32–1.61)1.26 (0.58–2.74)0.38 (0.15–0.94)0.90 (0.27–2.98)
 Q31.44 (0.70–2.95)0.90 (0.41–1.96)0.91 (0.43–1.90)0.50 (0.15–1.73)
 Q41.36 (0.69–2.67)0.76 (0.34–1.71)0.77 (0.37–1.59)1.07 (0.37–3.06)
P (trend)0.170.350.960.93
  • a Gleason scores 7 and greater were classified in the high group [quartiles of serum selenium (μg/dl) distribution: Q1 (7.59–10.13); Q2 (10.14–11.47); Q3 (11.48–12.46); and Q4 (12.47–21.96)] and scores 6 and lower in the low group [quartiles of serum selenium (μg/dl) distribution: Q1 (5.07–10.10); Q2 (10.11–11.24); Q3 (11.25–12.78); and Q4 (12.79–17.60)].

  • b Advanced stage of cancer includes pathological stages 3 (n = 23) and 4 (n = 5) and clinical stages 3 (n = 4) and 4 (n = 5). Early stage quartiles of serum selenium (μg/dl) distribution: Q1 (5.07–10.26); Q2 (10.27–11.44); Q3 (11.45–12.97); and Q4 (11.98–17.60). Late stage quartiles of serum selenium (μg/dl) distribution: Q1 (7.74–9.89); Q2 (9.90–11.45); Q3 (11.46–12.44); and Q4 (12.45–21.96).

  • c OR from conditional logistic regression model stratified on year of randomization, age at randomization within 5-year intervals, smoking status at randomization, intervention arm, exposure population, and blood draw visit.