This study extends research on associations between smoking behavior and chronic disease by following a male cohort from initiation of regular smoking behavior into old age. Because smoking was measured at multiple points over the participants’ lifetime, this study presented a unique opportunity to examine the natural history of smoking behavior. Three major findings emerged. First, the sample contained five distinct smoking trajectories based on the age at which participants quit daily smoking. Second, those participants following smoking trajectories with later cessation had a higher likelihood of developing lung disease than those who quit smoking at an earlier age. Finally, participants following trajectories with later cessation lived shorter lives.
