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.
“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 Dr. Muscat. "It may be a combination of genetic and personal factors that cause a higher dependence to nicotine.”
Tobacco use causes about 90 percent of lung cancer death in men and 80 percent in women. Tobacco use is attributed to many other types of cancer as well, including mouth, throat and tongue cancers, pharynx, larynx, esophagus, bladder, stomach, cervix, kidney and pancreatic cancers, and acute myeloid leukemia.
A 2011 National Research Council report shows the U.S. life expectancy is now lower than most every other industrialized country and cigarette smoking is to blame. While smoking rates among Americans continue to decline—now 23.5 percent for men and 17.9 percent for women, according to the Centers for Disease Control and Prevention— the number of people who smoked during the mid-1950s was around 57 percent. The impact of smoking several decades ago is reflected by our current life expectancy rate, the council report says.
Lynette Summerill, an award-winning writer and scuba enthusiast lives in San Diego, CA. In addition to writing about cancer-related issues for EmpowHER, her work has been seen in newspapers and magazines around the world.
Sources: Cancer. Nicotine dependence phenotype, time to first cigarette, and risk of head and neck cancer. Joshua E. Muscat, Kwangmi Ahn, John P. Richie Jr., and Steven D. Stellman. Article first published online: 8 AUG 2011 | DOI: 10.1002/cncr.26235 Abstract and article at: http://onlinelibrary.wiley.com/doi/10.1002/cncr.26235/abstract
Cancer. Nicotine dependence phenotype and lung cancer risk. Joshua E. Muscat, Kwangmi Ahn, John P. Richie Jr and Steven D. Stellman. Article first published online: 8 AUG 2011 | DOI: 10.1002/cncr.26236 Abstract and article at:
http://onlinelibrary.wiley.com/doi/10.1002/cncr.26236/abstract
U.S. Department of Health and Human Services. The Health Consequences of Smoking: A Report of the Surgeon General. Accessible online at:
http://www.surgeongeneral.gov/library/smokingconsequences/index.html
The Centers for Disease Control and Prevention. Adult Smoking Rates in the United States: Current Estimate. Accessed online at:
http://www.cdc.gov/tobacco/data_statistics/fact_sheets/adult_data/cig_smoking/index.htm
National Research Council. International Differences in Mortality at Older Ages: Dimensions and Sources. National Academies Press, 2011. Accessed online at:
http://www.nap.edu/catalog.php?record_id=12945#description
Reviewed August 11, 2011
by Michele Blacksberg R.N.
Edited by Jody Smith