Table 4

Mean and risks of lung cancer by quartile of control selenium (μg/dl) distributionsa

OverallGenderBaseline smoking statusExposure populationTreatment arm
MaleFemaleFormerCurrentAsbestosHeavy smokerPlaceboActive
Mean (SD)
 Case11.91 (1.96)11.70 (1.87)12.42 (2.09)12.07 (1.96)11.85 (1.96)11.33 (1.71)12.12 (2.00)11.93 (2.01)11.90 (1.92)
 Control11.77 (1.85)11.58 (1.76)12.14 (1.96)11.99 (1.87)11.68 (1.83)10.88 (1.82)12.09 (1.75)11.69 (1.79)11.84 (1.89)
ORsb (95% CI)
 Q11.001.001.001.001.001.001.001.001.00
 Q21.02 (0.66–1.56)1.35 (0.80–2.28)0.57 (0.19–1.68)0.85 (0.36–2.02)1.08 (0.66–1.77)1.07 (0.53–2.17)0.92 (0.53–1.58)0.68 (0.36–1.29)1.37 (0.77–2.43)
 Q30.93 (0.57–1.48)1.18 (0.66–2.08)0.38 (0.12–1.19)1.04 (0.43–2.52)0.89 (0.53–1.50)1.72 (0.73–4.07)0.71 (0.41–1.23)0.71 (0.36–1.39)1.14 (0.63–2.06)
 Q41.20 (0.77–1.88)1.53 (0.83–2.82)0.76 (0.29–2.01)1.19 (0.49–2.88)1.21 (0.71–2.04)2.50 (0.96–6.47)0.93 (0.54–1.60)1.35 (0.70–2.61)1.09 (0.60–1.98)
P (trend)0.490.260.750.570.640.050.710.320.40
  • a Quartiles of serum selenium (μg/dl) distribution: Q1 (6.39–10.55); Q2 (10.56–11.76); Q3 (11.77–12.93); and Q4 (12.94–17.23).

  • b 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.