The longer someone smokes, the more likely that person is to have chronic back pain, a new study said.

More than 8,000 people were interviewed on the phone by the Robert Koch institute in 2003.

The authors said in a news release that smokers and former smokers who had used tobacco for more than 16 years were twice as likely to have back pain than people who smoked less than 10 years.

They said, however, that how much people smoke and how often did not seem to change the rates of pain.

The authors pointed out that tobacco consumption does not necessarily cause chronic back pain. It is just as possible that people with chronic back pain smoke to alleviate the pain.