Declines in cigarette smoking among Americans since the mid-1950s—particularly since tobacco-control policies and interventions were implemented after the U.S. Surgeon General's Report on Smoking and Health was released in 1964—prevented nearly 800,000 lung cancer deaths between 1975 and 2000, according to a study led by Hutchinson Center researchers.
Results of the National Cancer Institute-funded study, conducted by a consortium of six research groups in the U.S. and the Netherlands, were published online March 14 in the Journal of the National Cancer Institute.
Estimating impact of tabacco-control efforts
For the study, the researchers, part of the NCI's Cancer Intervention and Surveillance Modeling Network, reconstructed detailed smoking histories for those born between 1890 and 1970, and then estimated lung cancer deaths associated with these smoking histories using mathematical equations. In this way, the researchers were able to estimate the impact of changes in smoking patterns resulting from tobacco-control efforts on deaths from lung cancer between 1975 and 2000.
"This is the first attempt to quantify the impact of changes in smoking behaviors on lung cancer mortality based on detailed reconstruction of cigarette smoking histories," said lead author Dr. Suresh Moolgavkar, an epidemiologist, biostatistician and mathematical modeler in the Public Health Sciences Division. He is an expert in devising formulas, equations and computer programs that simulate and predict biological processes. Such studies contribute to the understanding of cancer risks associated with exposures to toxic chemicals such as cigarette smoke.
Since the mid-1960s, tobacco-control efforts in the U.S. have included:
- Restrictions on smoking in public places
- Increases in cigarette excise taxes
- Limits on underage access to cigarettes
- Efforts to increase public awareness of the hazards of smoking.
In addition to modeling the impact of actual tobacco control efforts on lung cancer mortality rates, the researchers, including PHS coauthors Drs. Jihyoun Jeon and Rafael Meza, also estimated lung cancer deaths between 1975 and 2000 under two opposite scenarios:
- If all U.S. cigarette smokers had successfully quit smoking in the wake of the 1964 Surgeon General's report and no one else started smoking, an estimated 2.5 million people would have not died from lung cancer (1.6 million men and 883,000 women would not have been diagnosed with the disease).
- In the absence of tobacco control programs and policies, if smoking behaviors had not changed after the Surgeon General's report, an additional 552,000 men and 243,000 women would have died of lung cancer.
"These findings provide a compelling illustration of the devastating impact of tobacco use in our nation and the enormous benefits of reducing rates of smoking," said Dr. Robert Croyle, director of the NCI's Division of Cancer Control and Population Sciences. "Although great strides have been made, we cannot relax our efforts. The prevention and cessation of tobacco use continue to be vital priorities for the medical, scientific and public health communities."
In addition to the Hutchinson Center, other members of the research consortium included Erasmus Medical Center in Rotterdam, Netherlands; Pacific Institute for Research and Evaluation in Calverton, Md.; Rice University and M.D. Anderson Cancer Center in Houston; Massachussetts General Hospital and Harvard Medical School in Cambridge, Mass.; and Yale University in New Haven, Conn.