MONDAY, Aug. 8 (HealthDay News) -- Smokers who light up right after they wake up in the morning may be at greater risk for lung, head and neck cancers than those who wait longer before having their first cigarette of the day, a new study finds.

The study was released online Aug. 8 in advance of publication in an upcoming print issue of the journal Cancer.

"These smokers have higher levels of nicotine and possibly other tobacco toxins in their body, and they may be more addicted than smokers who refrain from smoking for a half hour or more," said Joshua Muscat, of Penn State College of Medicine in Hershey, in a journal news release. "It may be a combination of genetic and personal factors that cause a higher dependence to nicotine."

In the study, researchers compared 4,775 lung cancer patients with 2,835 smokers who didn't have cancer. They found that those who smoked 31 to 60 minutes after waking up were 1.3 times more likely to develop lung cancer than those who waited at least an hour before lighting up. Meanwhile, those who smoked within 30 minutes of waking up were 1.79 times more likely to develop lung cancer.

In a separate analysis, the investigators compared 1,055 smokers with head and neck cancer with 795 smokers without the disease. Those who smoked 31 to 60 minutes after waking up were 1.42 times more likely to develop cancer than those who waited more than 60 minutes to have a cigarette. Smokers who had their first cigarette within a half hour of waking up were 1.59 times more likely to develop head and neck cancer.

The findings suggest the desire to have a cigarette immediately after waking up may increase smokers' risk for cancer, the researchers concluded. As a result, these smokers would benefit from smoking cessation programs that specifically target this early morning behavior and the greater risks involved, they added.

More information

The U.S. Centers for Disease Control and Prevention provides more information on the health effects of smoking.