Smoking-attributable mortality by cause of death in the United States: An indirect approach

More than 50 years after the U.S. Surgeon General's first report on cigarette smoking and mortality, smoking remains the leading cause of preventable death in the United States. The first report established a causal association between smoking and lung cancer, and subsequent reports expanded the list of smoking-attributable causes of death to include other cancers, cardiovascular diseases, stroke, and respiratory diseases. For a second level of causes of death, the current evidence is suggestive but not sufficient to infer a causal relationship with smoking. This study draws on 1980-2004 U.S. vital statistics data and applies a cause-specific version of the Preston-Glei-Wilmoth indirect method, which uses the association between lung cancer death rates and death rates for other causes of death to estimate the fraction and number of deaths attributable to smoking overall and by cause. Nearly all of the established and additional causes of death are positively associated with lung cancer mortality, suggesting that the additional causes are in fact attributable to smoking. I find 420,284 annual smoking-attributable deaths at ages 50+ for years 2000-2004, 14% of which are due to the additional causes. Results corroborate recent estimates of cause-specific smoking-attributable mortality using prospective cohort data that directly measure smoking status. The U.S. Surgeon General should reevaluate the evidence for the additional causes and consider reclassifying them as causally attributable to smoking.