A new study entitled “What proportion of cancer deaths in the contemporary United States is attributable to cigarette smoking?” reports that cigarrete smoking is still a leading cause of cancer death in the United States and public health measures to reduce smoking prevalence are still urgently required. The study was published in the Annals of Epidemiology.
Smoking is an established cause of harm to nearly every organ and, therefore, a potential cause for cancer throughout the body, but also for cardiovascular and respiratory diseases. According to the Centers for Disease Control and Prevention, smoking increases up to 4 times the risk for coronary heart disease and stroke, and 25 to 25.7 times the risk of developing lung cancer, in men and women, respectively.
An analysis performed in 1981 by researchers Richard Doll and Richard Peto, calculated that smoking was the cause of cancer deaths in 30% of all cancers in the United States. However, since then, no other estimate study was performed.
In this study, the authors wanted to estimate the population attributable fraction (PAF), a parameter that indicates cancer deaths caused by smoking. As such, they analyzed smoking rate’s data retrieved from the National Health Interview Survey (NHIS) as well as epidemiologic studies reporting risk associated with smoking.
The authors were capable of estimating, in a conservative analysis including solely cancer deaths attributable to smoking, that cigarette smoking was responsible for 28.7% of all cancer deaths registered in the United Sates during 2010. When they included all cancer deaths, the PAF parameter rose to 31.7%. Notably, their estimates were restricted to cigarette smoking, since the authors did not include additional sources of harm, such as environmental tobacco smoke or other smoking devices such as cigars, pipes, or smokeless tobacco.
The authors highlight that their results are similar to the 30% estimates calculated in 1981 by researchers Doll and Peto, despite the decline observed in smoking prevalence throughout the years. While the authors fully acknowledge that the decline in smoking prevalence was crucial to decrease cancer mortality and PAF due to smoking, they point other factors responsible for the increase in PAF estimates, such as adding new cancers to the list of cancers-associated with smoking, the increase of deaths among women associated to lung cancer and the decrease in cancer deaths due to factors other than smoking.
As the authors noted, “Our results indicate that cigarette smoking causes about three in 10 cancer deaths in the contemporary United States. Reducing smoking prevalence as rapidly as possible should be a top priority for US public health efforts to prevent future cancer deaths.”
