Tobacco use has long been known to cause lung cancer and increased morbidity in smokers. A study sponsored by the National Cancer Institute (NCI) recently revealed the positive impact of U.S.-initiated tobacco control policies and programs with the prevention of 795,000 lung cancer deaths from 1975 through 2000.
Researchers at MD Anderson and Rice University collaborated as one of six lung cancer modeling groups for the NCI-sponsored Cancer Intervention and Surveillance Modeling Network Consortium. They applied a comparative modeling approach in which detailed smoking histories of 30- to 84-year-olds born from 1890 to 1970 were related to lung cancer mortality in mathematical models.
Using these models, researchers analyzed the impact of changes in smoking patterns resulting from tobacco control activities initiated after the U.S. Surgeon General's Report on Smoking and Health was released in 1964.
Tobacco control effort
After the release of the landmark report, more emphasis was placed on smoking cessation, including restrictions on smoking in public places and underage access to tobacco, as well as tax increases on cigarettes.
"While the number of deaths averted by the tobacco control efforts is remarkable, we're only taking into account lung cancer mortality estimates," says Olga Gorlova, Ph.D., associate professor in the Department of Epidemiology and MD Anderson's principal investigator on the national study. "The analysis doesn't take into consideration the affect tobacco has on other cancers and other diseases, which makes the potential for overall impact even more astounding."
In this study researchers created three concepts: "no tobacco control," "complete tobacco control" and "actual tobacco control."
In the "no tobacco control" concept, researchers considered the worst-case scenario where there is no change in smoking trends following the Surgeon General's Report. In essence, this means health care policies and tobacco laws stayed the same as if no report had been released, and smokers didn't change their habits. According to the models, if this concept had been a reality, about 800,000 more lives would have been lost to lung cancer.
In the ideal scenario, "complete tobacco control," the modeling results indicate that 2.5 million lives could have been saved if all smoking had ceased completely and no new smokers started the habit.
"We have a long way to go to reach a level of control close to this," Gorlova says. "It will take stricter health care laws and policies, more funding and more aggressive smoking-cessation messaging targeted toward children and adolescents to prevent them from starting smoking and becoming addicted to nicotine."
The "actual tobacco control" concept reproduced the actual smoking behaviors of men and women in the United States following the Surgeon General's Report, and the researchers estimated lung cancer deaths of 552,000 men and 243,000 women were averted from 1975 to 2000.
Lung cancer continues to be the number one cancer killer among men and women around the world, with more than 160,000 deaths expected in the United States this year.
This groundbreaking study quantifying the impact of changes in smoking behaviors using the comparative modeling approach lays the foundation for better opportunities to prevent, treat and reduce the incidence of lung cancer, other cancers, as well as other diseases.