Cigarette Smoking: Health Risks and How to Quit (PDQ®): Prevention - Health Professional Information [NCI] - Significance
In the United States, smoking-related illnesses accounted for an estimated 443,000 deaths each year between 2000 and 2004.[1,2] (Also available online.) On average, these deaths occur 12 years earlier than would be expected, so the aggregate annual loss exceeds 5 million life-years. These deaths are primarily due to smoking's role as a major cause of cancer, cardiovascular diseases, and chronic lung diseases. The known adverse health effects also include other respiratory diseases and symptoms, nuclear cataract, hip fractures, reduced female fertility, and diminished health status. Maternal smoking during pregnancy is associated with fetal growth restriction, low birth weight, and complications of pregnancy. It has been estimated that at least 30% of cancer deaths and 20% of all premature deaths in the United States are attributable to smoking.
Tobacco products are the single, major avoidable cause of cancer, causing more than 155,000 deaths among smokers in the United States annually due to various cancers. The majority of cancers of the lung, trachea, bronchus, larynx, pharynx, oral cavity, nasal cavity, and esophagus are attributable to tobacco products, particularly cigarettes. Smoking is also causally associated with cancers of the pancreas, kidney, bladder, stomach, and cervix and with myeloid leukemia.[4,6]
Chronic eosinophilic leukemia (CEL) is a chronic myeloproliferative disorder of unknown etiology in which a clonal proliferation of eosinophilic precursors results in persistently increased numbers of eosinophils in the blood, bone marrow, and peripheral tissues. In CEL, the eosinophil count is greater than or equal to 1.5 × 109 /L in the blood. To make a diagnosis of CEL, there should be evidence for clonality of the eosinophils or an increase in blasts in the blood or...
Smoking also has substantial effects on the health of nonsmokers. Environmental or secondhand tobacco smoke is implicated in causing lung cancer and coronary heart disease. Among children, secondhand smoke exposure is causally associated with sudden infant death syndrome, lower respiratory tract illnesses, otitis media, middle ear effusion, exacerbated asthma, and respiratory effects such as cough, wheeze, and dyspnea.
Environmental tobacco smoke has the same components as inhaled mainstream smoke, although in lower absolute concentrations, between 1% and 10%, depending on the constituent. Carcinogenic compounds in tobacco smoke include the polycyclic aromatic hydrocarbons (PAHs), including the carcinogen benzo[a]pyrene (BaP) and the nicotine-derived tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Elevated biomarkers of tobacco exposure, including urinary cotinine, tobacco-related carcinogen metabolites, and carcinogen-protein adducts, are seen in passive or secondhand smokers.[7,9,10,11]
In 2011, 21.6% of adult men and 16.5% of adult women in the United States were current smokers. (Also available online.) Cigarette smoking is particularly common among American Indians and Alaska Natives. The prevalence of smoking also varies inversely with education, and was highest among adults who had earned a General Educational Development diploma (49.1%) and generally decreased with increasing years of education. (Also available online.) From 2000 to 2011, significant declines occurred in the use of cigarettes among middle school (10.7% to 4.3 %) and high school (27.9% to 15.8%) students. (Also available online.) Cigarette smoking prevalence among male and female high school students increased substantially during the early 1990s in all ethnic groups but appears to have been declining since approximately 1996.[14,15] (Also available online.)