No safe level of tobacco smoke

In this American prospective cohort study (JAMA Intern Med 2017;177:87–95. http://dx.doi.org/10.1001/jamainternmed.2016.7511), a dose-dependant association between the number of cigarettes smoked per day at baseline and all cause mortality was shown. It demonstrated that even low intensity smokers (defined as smokers who consistently smoked on average less than one cigarette per day over their lifetime) had a higher risk of death from all causes when compared to never smokers. This group of patients was shown to have a 64% higher risk of earlier death. Patients who smoked between 1 and 10 cigarettes per day had a reported 87% higher risk of death. Lung cancer mortality, in particular, was found to have a strong association, with increased risk of lung cancer death being 9 times and 12 times higher for low intensity smokers and for patients who smoked 1–10 cigarettes per day respectively. This highlights the importance of smoking cessation for all patients, even at low levels of smoking, and …