Smoking Risk Rising for Bladder Cancer
Article date: August 22, 2011
By Stacy Simon
Smokers’ risk of getting bladder cancer is higher than previously reported, according to a study by researchers at the National Cancer Institute that was published in the Journal of the American Medical Association. And the risk for women who smoke is just as high as it is for men.
Smokers vs. Nonsmokers
Researchers analyzed data from nearly 500,000 people who had taken part in the questionnaire-based NIH-AARP Diet and Health Study and were followed between October 1995 and December 2006. Researchers found that smokers were about 4 times as likely to get bladder cancer as people who never smoked. Previous research had showed smokers were about 3 times as likely to get bladder cancer.
Quitting lowered the risk, and the longer smokers had been tobacco-free, the lower their risk. On average, former smokers were about twice as likely to get bladder cancer as people who had never smoked.
The researchers suggest the change in risk may be due partly to a change in cigarette ingredients over the past several decades. While there have been some decreases in the concentrations of tar and nicotine, there have been increases in concentrations of certain carcinogens associated with bladder cancer. The overall rates of bladder cancer have stayed about the same during this time, but this may be due to fact that fewer people smoke now than in the past.
While previous studies showed that smoking was responsible for 20% to 30% of bladder cancers in women, the new study found that smoking now accounts for about half of female bladder cancer cases. It also shows that smoking is responsible for about half of male bladder cancer cases, which is similar to previous studies.
The increase in the proportion of bladder cancer cases among women attributable to smoking may be a result of increased smoking by women during the years since the previous studies were conducted. Women today are nearly as likely as men to smoke.
Even though smoking carries the same risk for men and women, men are still about 4 times as likely to be diagnosed with bladder cancer. The researchers suggest that exposure to carcinogens on the job in typically male occupations, as well as hormonal differences, may contribute to the gender disparity.
Previous and current research cites tobacco as the best established risk factor for bladder cancer in men and women. If you smoke and want help quitting, visit our guide to quitting smoking.
Reviewed by: Members of the ACS Medical Content Staff
ACS News Center stories are provided as a source of cancer-related news and are not intended to be used as press releases.
Citation: Association Between Smoking and Risk of Bladder Cancer Among Men and Women. Published in the August 17, 2011 issue of the Journal of the American Medical Association (Vol. 306, No. 7). First author: Neal D. Freedman, PhD, MPH, National Cancer Institute, Department of Health and Human Services, Rockville, Md.
Thank you for your feedback.