Tobacco use: a chronic illness?

Tobacco use is a modifiable risk factor that has many characteristics of a chronic illness. We analyzed longitudinal data from participants in the Atherosclerosis Risk in Communities Study (ARIC) and the Cardiovascular Health Study (CHS) and compared tobacco use to other chronic illnesses to evaluate effects on mortality. We limited our analysis to 20,293 participants aged 45 and older at baseline. We determined smoking status, diabetes status, hypertension, cardiovascular disease (ASCVD), and lung disease status at baseline. We developed Cox proportional hazard models, adjusting for age, sex and race and all comorbid diseases, to determine the effect of disease on mortality at up to 13 years of follow-up, 3,022 study participants died during the follow-up period. Adjusted proportional hazard models found that the risk of smoking for death had a hazard ratio (HR) of 2.0 (95% confidence interval [CI] 1.8, 2.2). This was similar to the mortality risk for ASCVD (HR 1.8, 95% CI 1.7, 2.0), diabetes (HR 1.9, 95% CI 1.7, 2.0), and chronic obstructive pulmonary disease (COPD) (HR 2.1, 95% CI 1.9, 2.4). The risk in former smokers were significantly less than that of current smokers (HR 1.1, 95% CI 1.01, 1.2). In the adjusted models, current cigarette smoking has a mortality risk that is in the same range of that seen in other "chronic diseases", whereas the risk in former smokers is greatly reduced. These data suggest that current smoking should be approached as aggressively as other chronic diseases that are amenable to interventions.