National Cancer Institute researchers say in a new study that the longer you smoke, the higher your risk for the particularly deadly disease of pancreatic cancer.

Reuters reported Aug. 18 that researchers led by Shannon M. Lynch found that long-term smokers were at  greater risk of disease even if their total cigarette consumption was the same as someone who smoked for a shorter duration. Smokers in general are 1.77 times more likely to get pancreatic cancer than nonsmokers, but risk rose along with the number of cigarettes smoked daily, the length of time spent as a smoker, and the total “smoking dose” (calculated by daily intake and duration of use).

Even former smokers who had quit for 10 years or more remained at elevated risk of pancreatic cancer, researchers found. An estimated 15 percent of pancreatic cancers are caused by smoking, the study said.

The findings were reported in the Aug. 15, 2009 issue of the American Journal of Epidemiology.