Several carcinogenic biomarker levels elevated in cigar smokers
Cigar smoking is linked to higher levels of carcinogenic tobacco exposure biomarkers and may be as harmful as cigarette smoking, according to study findings.
Prior surveys have determined that cigar smokers, especially among young people, commonly believe that cigars are less addictive and less harmful than cigarettes, possibly because most cigar smokers who never previously smoked cigarettes do not report inhaling smoke into their lungs.
However, further study revealed that cigar smokers who have previously smoked cigarettes were more likely to inhale cigar smoke than cigar smokers; in addition, researchers identified that all cigar smokers inhale smoke to some degree.
“Cigar smoking exposes users to similar types of harmful and cancer-causing agents as cigarette smoking,” researcher Jiping Chen, MD, of the Center for Tobacco Products at the FDA, said in a press release.
In the cross-sectional analysis, Chen and colleagues evaluated 25,522 participants in the National Health and Nutrition Examination Survey, 1999-2012. Information about cigar smoking habits was obtained through a questionnaire addressing recent tobacco use, and the participants also underwent a physical examination that included the collection of blood and urine samples. The samples were tested for the following biomarkers: serum cotinine, urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), blood lead, blood cadmium and urinary arsenic.
Participants were stratified into five groups based on lifetime cigarette/cigar smoking status and during the previous 5 days. They were classified as nontobacco users, primary cigar smokers, and secondary cigar smokers, and cigar smokers were additionally subclassified as daily cigar smokers or nondaily cigar smokers. The researchers determined the geometric mean concentrations for each exposure biomarker by tobacco use category and calculated geometric mean ratios adjusting for demographic characteristics.
The researchers found that compared with nontobacco users, cigar smokers had higher levels of cotinine, NNAL and lead. Among primary cigar smokers (current cigar smokers who had never smoked cigarettes), the geometric mean concentration of cotinine was 6.2 ng/mL (95% CI, 4.2-9.3) vs. nontobacco users, who had a geometric mean concentration of 0.045 ng/mL (95% CI, 0.043-0.048).
Primary cigar smokers had a geometric mean concentration of NNAL of 19.1 pg/mg creatinine (95% CI, 10.6-34.3) vs. 1.01 pg/mg creatinine (95% CI, 0.95-1.07) for nontobacco users. Compared with nontobacco users, secondary cigar smokers (current cigar smokers/former cigarette smokers) and dual cigar/cigarette smokers had higher concentrations of cadmium.
After controlling for demographic characteristics, the association persisted between cigar smoking and significantly higher levels of cotinine, NNAL, cadmium and lead. Daily cigar smokers exhibited NNAL levels comparable to those of daily cigarette smokers.
“Our finding that cigar smoking is significantly associated with higher concentrations of biomarkers of tobacco exposure regardless of cigarette smoking status underscores the need for developing successful strategies for reducing the health burden associated with cigar smoking in the United States,” Chen and colleagues wrote. “These efforts should include both preventing people from initiating cigar smoking and encouraging current cigar smokers to quit.”
Disclosure: The researchers report no relevant financial disclosures.