Cigars Increase Lung Cancer Risk Five-Fold, Per American Cancer Society/CDC Study in JNCI
ATLANTA, Feb. 15 /PRNewswire/ -- Cigar smoking is associated with greatly increased risk of death from several highly fatal cancers, according to a study by researchers from the American Cancer Society and the Centers for Disease Control and Prevention (C
Most significantly, the researchers found a five-fold overall increased risk of death from lung cancer among male cigar smokers -- a much greater risk than had been previously reported in the U.S. That risk increased further among men who reported smoking three or more cigars a day (to 7.8 times the risk of men who have never smoked) and men who inhale their cigar smoke (who have 11.3 times the risk of lung cancer death of nonsmokers). However, even men who said they did not inhale their cigar smoke had lung cancer death rates more than three times that of men who had never smoked. According to Dr. Jacobs, a co-author on the study and senior epidemiologist at the American Cancer Society, ``We expected to find some increased risk of lung cancer, but we found that cigar smoking is much more lethal than we thought.''
Cigar smoking also increased risk of death from cancer of the larynx by more than 10 times and cancer of the oral cavity/pharynx by four times. Current cigar smokers who said they inhaled their cigar smoke were 2.7 times more likely to die of pancreatic cancer and 3.6 times more likely to die of bladder cancer than men who never smoked.
``Results from this large prospective study support a strong association between cigar smoking and mortality from several types of cancer,'' the authors conclude.
The findings come from one of the largest prospective studies ever of cigar smoking and cancer. The investigators evaluated data on more than 137,000 U.S. men participating in the American Cancer Society's Cancer Prevention Study-II. After study participants completed a CPS-II questionnaire in 1982, more than 7,800 men were categorized as current cigar smokers, meaning they smoked at least one cigar daily and had never regularly smoked cigarettes or pipes, another group of approximately 7,800 men were categorized as former cigar smokers and more than 121,000 were categorized as never smokers. The majority of men in the analysis were white and middle-aged or elderly.
The researchers followed the men for 12 years, identified those who died of cancer during that time period and used statistical analyses to characterize the association between cigar smoking and death from tobacco-related cancers, after accounting for other cancer risk factors.
``The number of cigars consumed in the United States increased by approximately 50 percent between 1993 and 1998,'' the authors write, citing government data. ``This rapid increase is particularly striking because it followed a 66 percent decline from 1964 through 1993. While cigarette smoking is an important and well-established cause of many cancers, less is known about the relationship between cigar smoking and the risk of cancer. Cigars may not be perceived as a substantial health hazard, possibly because cigars are not required to carry a health warning from the Surgeon General or because of endorsements from celebrities associated with health and fitness ... ''
According to the authors, ``The importance of cigar smoking as a potential emerging public health hazard is illustrated by data from the 1997 Youth Risk Behavior Survey showing that 31 percent of U.S. high school boys and 11 percent of U.S. high school girls had reported smoking a cigar within the past 30 days. Our results, together with those from previous studies, indicate that, if these young people become regular cigar smokers, a sizable number will develop a smoking-related cancer later in life.''
The authors said that despite reports from tobacco-industry sources that the ``cigar craze'' is over, the latest figures from the U.S. Department of Agriculture show that cigar consumption in 1999 was the highest in recent history, with a small decline in large cigar consumption more than offset by an increase in consumption of smaller cigars, which are likely easier for children to get because they are usually less expensive.
The researchers speculate that one reason they found higher death rates from lung cancer than reported in previous U.S. studies of cigar smoking is that there may have been changes over time in the type of cigars smoked in the U.S., with cigars becoming more lethal over time.
According to the authors ``changes in the pH of cigars may be particularly important with respect to lung cancer because of the potential effect of pH on inhalation patterns. While the pH of cigars is higher than cigarettes, pH varies greatly between cigar types, with some brands having low pH levels close to those of cigarettes. Low pH cigars may be particularly hazardous, since, like cigarettes, they may require some degree of inhalation to achieve substantial nicotine absorption, and their smoke may contain less free ammonia and, therefore, be easier to inhale than the smoke from high pH cigars ... ''
Study authors are Jean A. Shapiro, PhD, (first author) of CDC's National Center for Chronic Disease Prevention and Health Promotion, Division of Cancer Prevention & Control; and Eric J. Jacobs, PhD, and Michael J. Thun, MD, of the American Cancer Society's Department of Epidemiology and Surveillance Research.
The American Cancer Society is the nationwide, community-based, voluntary health organization dedicated to eliminating cancer as a major health problem by preventing cancer, saving lives and diminishing suffering from cancer, through research, education, advocacy and service.