The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.

Summary of Evidence

Added text to include specific types of cancer caused by cigarette smoking (cited U.S. Department of Health and Human Services [USDHHS], Office on Smoking and Health, as reference 2).

Updated statistics about how counseling improves cessation rates (cited Lancaster et al. as reference 3 and Lemmens et al. as reference 4).

Added Physician Advice and Smoking Cessation as a new subsection.

Added text about nicotine replacement therapy treatments and updated statistics; added text about treatment with bupropion improving cessation rates over placebo after 6 months; added text about varenicline therapy treatment improving cessation rates over placebo after 6 months (cited Silagy et al. as reference 5, Hughes et al. as reference 6, and Cahill et al. as reference 7).

Significance

Updated cancer mortality estimates for smoking-related illnesses between 2000 and 2004 (cited American Cancer Society as reference 1). Also added text to include the role of smoking as a major cause of cancer, known adverse health effects, and the relationship of fetal growth restriction, low birth weight, and complications of pregnancy to maternal smoking during pregnancy (cited USDHHS, Office on Smoking and Health, as reference 3).

Added text about some effects of secondhand smoke on children (cited USDHHS, Office on Smoking and Health, as reference 6).

Added text about environmental tobacco smoke having the same components as inhaled mainstream smoke but in lower absolute concentrations; added that carcinogenic compounds in tobacco smoke include the polycyclic aromatic hydrocarbons; also added that elevated biomarkers of tobacco exposure are seen in passive or secondhand smokers (cited Cinciripini et al. as reference 7, Finette et al. as reference 8, Benowitz et al. as reference 9, and Hecht as reference 10).

Updated statistics about the percentages of adult male and adult female smokers in the United States and the relationship between the prevalence of smoking with the levels and years of education of the smoker (cited Centers for Disease Control as reference 11 and Jemal et al. as reference 12).

Updated statistics to show the effect of tobacco use on population-level health outcomes by citing the geographical location of the highest and lowest rates of the average annual age-adjusted lung cancer death rates in the United States.

Evidence of Benefit

Revised text to state that smokers who quit also lower their risk of cervical, gastric, and bladder cancer (cited USDHHS, Office on Smoking and Health, as reference 3).

Added Thomas et al. as reference 7.

Updated statistics about a meta-analysis of randomized controlled trials that show 6-month cessation rates are significantly improved with use of nicotine replacement therapy (NRT) products compared with placebo or no intervention (cited Silagy et al. as reference 12, Lemmens et al. as reference 13, and Lancaster et al. as reference 14).

Added text to state that an important issue is whether pharmacotherapies are more effective in the presence of counseling. Also added text to conclude that the results of a study suggest that the combination of pharmacotherapy plus counseling is no better than intervention alone.

Added the updated Treating Tobacco Use and Dependence guidelines for 2008 (cited Fiore et al. as reference 17).

Added text about a synthesis of the results of 110 randomized trials that showed that NRT treatments, alone or in combination, improve cessation rates over placebos after 6 months.

Added text to state that based on the results of 31 randomized trials that compared the antidepressant bupropion to placebo, after 6 months of follow-up bupropion was associated with a statistically significant increase in the likelihood of quitting smoking; however, there is insufficient evidence to support the idea that combining bupropion plus NRT increases smoking cessation rates compared to NRT alone (cited Hughes et al. as reference 25).

Added text to state that in two randomized controlled trials for smoking cessation, varenicline titrated to a dose of 1.0 mg twice a day and was compared with bupropion sustained-release 150 mg twice a day and with a placebo group (cited Jorenby et al. as reference 26, Gonzales et al. as reference 27, and Aubin et al. as reference 28).

Added text to state that based on postmarketing surveillance, on July 1, 2009, the U.S. Food and Drug Administration (FDA) required additions to the Boxed Warnings for both bupropion and varenicline to describe the risk of serious neuropsychiatric symptoms associated with these products (Cited FDA as reference 29).

Added text to state that there is a growing number of smoking cessation pharmacotherapies that have been shown to be efficacious in significantly increasing rates of smoking cessation.

Back to Top

< Previous Section  |  Next Section >