Table 5

Total cancer incidence by treatment group and baseline plasma selenium

Baseline plasma SeCasesIncidenceaUnadjustedbAdjustedc
SePlaceboSePlaceboRR95% CIPP, M-HHR95% CIPP, intd
By median
 ≤113.4 (ng/ml)46731.933.120.620.42–0.910.010.150.620.43–0.900.010.14
 >113.4 (ng/ml)59642.132.820.900.62–1.310.570.910.63–1.300.60
By tertile
 ≤105.2 (ng/ml)27541.713.440.500.30–0.800.0020.020.510.32–0.810.0050.007
 105.3–121.634462.133.030.700.44–1.120.120.700.44–1.090.11
 >121.6 (ng/ml)44372.912.441.190.75–1.900.431.200.77–1.860.43
  • a Annual cumulative incidence per 100 PY.

  • b RR and 95% CI were derived from incidence rate ratios; Ps were derived from log-rank (P) test and Mantel-Haenszel (P, M-H) test for heterogeneity.

  • c HR, 95% CI, and P values from the Cox proportional hazards models adjusted for age (continuous), gender, and smoking status (never, former, current) at baseline.

  • d P for treatment group characteristic interaction is for the (treatment group × factor) cross-product term in separate Cox proportional hazards models.