We all know smoking is bad, but it turns out that smoking is even worse for your health than previously thought. A study that combined data from five other large studies says that the mortality rate from smoking is higher than previously thought. Five more diseases and 60,000 more deaths a year in the United States may be attributed at least in part to smoking.
Smoking was known to be the cause of 12 types of cancer, 9 other diseases, and nearly 440,000 deaths a year in the United States before this study. Add in these additional 60,000 deaths and it adds up to half a million people dying earlier than they should have died, or about 1 in 5 deaths in America.
The study analyzed the combined data from five recent studies that included nearly one million people aged 55 and older. Those studies followed these people from 2000 to 2011, during which time there were 181,377 deaths, including 16,475 among active smokers. About 17% of the excess mortality among current smokers was due to conditions that are not currently thought to be due to smoking. Excess mortality means death rates beyond those seen in nonsmokers.
These conditions included kidney failure, heart disease due to high blood pressure, infections, inadequate blood circulation in the intestines, various respiratory diseases, breast cancer, and prostate cancer. For each of these diseases, a smoker was twice as likely to die as someone who never smoked. Among former smokers, the relative risk for each of these outcomes went down the longer it was since they had quit smoking.
The results of this study are not proof of a cause-and-effect, but the size of the study means that the findings are very strong.
The study was published in the New England Journal of Medicine and was funded by the American Cancer Society.