Cigarette Smoking and Cancer Risk: Modeling Total Exposure and Intensity (original) (raw)

A recent analysis showed that the excess odds ratio (EOR) for lung cancer due to smoking can be modeled by a function which is linear in total pack-years and exponential in the logarithm of smoking intensity and its square. Below 15-20 cigarettes per day, the EOR/pack-year increased with intensity (direct exposure rate or enhanced potency effect), suggesting greater risk for a total exposure delivered at higher intensity (for a shorter duration) than for an equivalent exposure delivered at lower intensity. Above 20 cigarettes per day, the EOR/pack-year decreased with increasing intensity (inverse exposure rate or reduced potency effect), suggesting greater risk for a total exposure FIGURE 1. Odds ratios for lung cancer according to pack-years of cigarette smoking (black squares) and fitted linear excess odds ratio (solid line) within categories of number of cigarettes smoked per day (Cigs/day), European Smoking and Health Study, 1976-1980. All odds ratios were calculated relative to never smokers and are plotted at the mean pack-years within each category. Bars, 95% confidence interval.