Gender differences in smoking attributable lung cancer mortality

Background: This study estimates differences in excess risk of lung cancer mortality due to smoking between males and females in the United States. Trends in excess risk are estimated by comparison with cohorts consisting of earlier birth cohorts: Cancer Prevention Studies-I and -II (CPS-I and CPS-II). Methods: Data from National Health Interview Survey (NHIS) respondents in 1987-2004 were combined with Multiple Causes of Death (MCD) files from 1987-2006 to create a cohort (N=322,768) for analysis. This was achieved through the use of social security numbers and other identifying information common to both databases. Subjects were followed for an average of 8.5 years (min=2.5 years; max=16.1 years). Probability sampling and survey weights were used to make the cohort nationally representative. Results: Among current smokers aged 65 years and older, relative risks of lung cancer for women were higher than for men. This finding differs from the gender differences observed in CPS-I and CPS-II. Conclusions: We used a representative data set to estimate gender differences in lung cancer relative risks. The excess risk of mortality from lung cancer has increased for women smokers. Possible reasons for this difference include changes in cigarette design and composition, and changes in duration and amount smoked by women starting in about the 1950's. Learning Objectives: 1. Compare lung cancer smoking excess risk between male and female smokers. 2. Compare estimates based on three major national cohort studies. 3. Describe the linkage between the National Health Interview Survey and the National Death Index.