Table 2.

Association of aspirin and nonaspirin NSAID use with colon cancer incidence, IWHS, 1992-2002

No. casesTotal person-yearsAge-adjusted HR95% CIMultivariable-adjusted HR*,95% CI
Aspirin Use
    Never15773,0711.00Referent1.00Referent
    ≤1 per week17388,9120.930.75-1.160.870.69-1.09
    2-5 per week8247,2350.820.63-1.070.790.59-1.04
    6+ per week9854,6050.830.64-1.070.760.58-1.00
510Ptrend = 0.091Ptrend = 0.036
Nonaspirin NSAID use
    Never323159,1791.00Referent1.00Referent
    ≤1 per week10349,1381.080.86-1.351.160.92-1.46
    2-5 per week2921,4240.690.47-1.000.630.41-0.96
    6+ per week5534,0830.810.61-1.080.850.63-1.15
510Ptrend = 0.024Ptrend = 0.032
  • * Adjusted for age (continuous), BMI (continuous), WHR (continuous), calcium intake (continuous), multivitamin use (yes and no), estrogen use (current and not current), family history of colon cancer (yes and no), physical activity (low, medium, and high), and smoking status (current, former, and never).

  • Aspirin analyses are adjusted for nonaspirin NSAID use and nonaspirin NSAID use analyses are adjusted for aspirin use.