Table 3.

Multivariate-adjusted HR of bladder cancer by years since quitting smoking in former smokers compared with current smokersa

VariableMulti-adjusted HR (95% CI)bVariableMulti-adjusted HR (95% CI)cMulti-adjusted HR (95% CI)d
Current smoker1.00Baseline current smoker
Current smokers Continuing smokers during follow-ups1.001.00
New quitters New quitters0.61 (0.40–0.94)
Never smokers0.23 (0.17–0.31)Never smokers0.21 (0.17–0.25)0.19 (0.15–0.24)
Former smoker (years since quitting smoking)0.61 (0.49–0.77)Former smoker (years since quitting smoking)
 <100.75 (0.56–0.99) —
 10–<200.65 (0.50–0.86) <200.55 (0.45–0.66)0.63 (0.45–0.88)
 20–<300.60 (0.45–0.79) 20–<300.48 (0.33–0.68)0.58 (0.49–0.69)
 ≥300.43 (0.32–0.59) ≥300.39 (0.27–0.55)0.39 (0.28–0.55)
P value for linear trende<0.0001P value for linear trend<0.0001<0.0001
  • aBaseline data and during clinical trial and observational study years 1, 3, 4, 5, 6, and 7 follow-ups. Models are adjusted for age, education, race/ethnicity, occupation, marital status alcohol consumption, physical activity, family history of cancer, BMI, daily total energy intake and percentage of energy from fat, daily fruit consumption and daily vegetable consumption, and pack-year of smoking.

  • bInformation on smoking was from baseline only.

  • cInformation on smoking was from both baseline and follow-ups. New quitters were separate from baseline former smokers for analysis.

  • dInformation on smoking was from both baseline and follow-ups. New quitters were combined with baseline former smokers for analysis.

  • eTrend test was performed among former smokers by treating the median values of each YSQ category as continuous variable in the multivariable adjusted Cox proportional hazard regression models.