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Smokers who need a cigarette soon after waking up in the morning may have a higher risk of lung cancer, and head and neck cancers than smokers who wait awhile to light up, two new studies find.
It’s no secret that cigarette smoking increases one's likelihood of developing various types of cancers. But Joshua Muscat, PhD, a research at Penn State College of Medicine in Hershey, and his colleagues wanted to know why only some smokers get cancer and not others?
The team investigated if nicotine dependence—characterized by the the amount of time after waking to a first cigarette—affects smokers' risk of lung and head and neck cancers independent of cigarette smoking frequency and duration.
Muscat says the studies’ findings, published early online in Cancer, a peer-reviewed journal of the American Cancer Society, could help identify smokers who have an especially high risk of developing cancer to reduce their risk.
Muscat’s team compared the early morning smoking habits of regular cigarette smokers, 4,775 with lung cancer and 2,835 without lung cancer. People who smoked within 30 minutes after waking were 1.79 times as likely to develop lung cancer as those who waited at least an hour or more before lighting up. People who waited 31 to 60 minutes after waking up were 1.31 times as likely to develop lung cancer as those in the one hour or more group.
In the second study, the team analyzed the early morning smoking habits of 1,055 regular cigarette smokers with head and neck cancers and 795 regular cigarette smokers without cancer. Compared with individuals who smoked more than one hour after waking, individuals who smoked 31 to 60 minutes after waking were 1.42 times as likely to develop head and neck cancer, and those who smoked within 30 minutes were 1.59 times as likely to develop head and neck cancer.
Smokers who light up first thing in the morning are at high risk of developing cancer, and would benefit from targeted smoking cessation programs, the studies’ authors said. Such interventions could help reduce tobacco's negative health effects as well as the costs associated with its use.