• 6/2/2004
  • Laurie Barclay, MD
  • Journal of the National Cancer Institute

Exclusive pipe smoking confers a risk of tobacco-associated disease similar to that of cigar smoking but less than that of cigarette smoking, according to the results of a prospective cohort trial published in the June 2 issue of the Journal of the National Cancer Institute.

Although many studies have examined the adverse health effects of pipe smoking combined with other forms of tobcco use, few have included large numbers of exclusive pipe smokers,” write S. Jane Henley, from the American Cancer Society in Atlanta, Georgia, and colleagues. “The prevalence of pipe smoking has declined since the 1960s, yet usage is still common regionally, especially among older populations.”
Previous studies of exclusive pipe smoking were small and could not exclude potential confounding factors, such as socioeconomic status and alcohol use. Pipe tobacco is the least commonly used tobacco product in the U.S., with overall use decreasing from 14% in 1965 to 2% in 1991. However, pipe smoking remains common among the American Indians and some other populations, and it has been increasing among American middle and high school students since 1999.

Of 138,307 men enrolled in the Cancer Prevention Study II, 15,263 men were current or former pipe users, and 123,044 men had never used tobacco. During the 18-year follow-up, there were 23,589 deaths. Based on this mortality data, the investigators compared the risks of death from nine cancers (bladder, colon/rectum, esophagus, kidney, larynx, lung, oropharynx, pancreas, and stomach) and three other diseases (coronary heart disease, cerebrovascular disease, and chronic obstructive pulmonary disease) in exclusive pipe smokers with mortality risks in nonsmokers.

Compared with never use of tobacco, current pipe smoking was associated with an increased risk of death from cancers of the lung (relative risk [RR], 5.00; 95% confidence interval [CI], 4.16 – 6.01), oropharynx (RR, 3.90; 95% CI, 2.15 – 7.08), esophagus (RR, 2.44; 95% CI, 1.51 – 3.95), colorectum (RR, 1.41; 95% CI, 1.15 – 1.73), pancreas (RR, 1.61; 95% CI, 1.24 – 2.09), and larynx (RR, 13.1; 95% CI, 5.2 – 33.1), and from coronary heart disease (RR, 1.30; 95% CI, 1.18 – 1.43), cerebrovascular disease (RR, 1.27; 95% CI, 1.09 – 1.48), and chronic obstructive pulmonary disease (RR, 2.98; 95% CI, 2.17 – 4.11).

Risks associated with pipe smoking were smaller than those associated with cigarette smoking but similar to those associated with cigar smoking.
Factors associated with increased relative risk of lung cancer were number of pipes smoked per day, years of smoking, and depth of inhalation, whereas increased number of years since quitting was associated with decreased risk.
A study limitation was that smoking habits were reported only at baseline.
“All tobacco products cause excessive morbidity and mortality,” the authors write. “Comprehensively documenting the deleterious health effects of pipe smoking is important in countering efforts by the tobacco industry to promote pipes as a desirable alternative to cigarettes or cigars.”

Source: J Natl Cancer Inst. 2004;96:853-861