Smoking first thing in the morning ‘ups’ cancer stakes

By Dr. Ananya Mandal, MDAug 8 2011

Scientists have found that people who need a cigarette within the first half hour of waking up are at a higher risk for lung, head and neck cancers. Actually this indicates a higher nicotine addiction.

Two studies released online Monday in the journal Cancer tracked smoking habits of thousands of smokers to see if those routines made a difference in their chances of getting certain types of cancer. How much time it takes to smoke the first cigarette after waking is considered one measure of nicotine addiction.

In the study on lung cancer the team analyzed data on 4,775 people with lung cancer and 2,835 regular smokers who comprised the control group. Participants who started puffing 31 to 60 minutes after waking were 1.31 times more likely to develop lung cancer than those who started smoking an hour or more after waking up. People who lit up within half an hour of waking were 1.79 times more likely to develop lung cancer that those who waited an hour.

In the study on head and neck cancers, the pool of participants included 1,055 people with head and neck cancers and a control group of 795 cigarette smokers. In this group, those who smoked their first cigarette between 31 to 60 minutes after waking were 1.42 times more likely to develop those types of cancers compared to men and women who smoked their first cigarette an hour or more upon waking. Those who grabbed their first cigarette within 30 minutes after waking were 1.59 times more likely to develop head and neck cancer compared to the group who waited an hour. Among types of head and neck cancers, the strongest association was noticed between smoking within a half-hour of waking and cancer of the pharynx, and the weakest link was with cancers of the tongue.

Authors write that early smoking may be due to genetic differences in nicotine addiction, socioeconomic factors, or both working together. Joshua Muscat of the Penn State College of Medicine said, “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.” He added, “, It may be a combination of genetic and personal factors that cause a higher dependence to nicotine.”

“What's interesting is that the studies show that if people are more addicted then they're at a greater risk of cancer, but that relationship is independent of how much people smoke,” John Richie, a professor of public health sciences and pharmacology at Penn State and a study author said. “Addiction is still not very well understood, and some smokers are clearly at much greater risk of cancer than others simply based on their addiction.”

Michael Fiore, director of the University of Wisconsin Center for Tobacco Research and Intervention, said the findings seem logical. “In essence when you have the first cigarette of the day is a surrogate for how addicted a person is,” says Fiore. “A lot of heavily addicted smokers overnight go into withdrawal. By the time they wake up, their blood nicotine level has fallen substantially, and their neuroreceptors are screaming, 'You gotta feed me.”

Richie and his colleagues say that their findings may help direct quitting programs towards the most addicted who are at the greatest risk. But first, he says, they need to know more about their smoking behaviors. “Do they inhale more deeply or take more puffs per cigarette?” These are things that can vary a lot smoker to smoker.