Study examines risk factors associated with colorectal cancer

December 09, 2003

Smoking, drinking alcohol at or above moderate levels, or having a first degree relative with colorectal cancer, are associated with an increased risk for having serious colon polyps, according to an article in the December 10 issue of The Journal of the American Medical Association (JAMA).

Colorectal cancer is the second leading cause of cancer death in North America, according to background information in the article. Evidence exists that screening asymptomatic populations beginning at age 50 years can reduce death due to colorectal cancer and that removal of precursor tumors may reduce the incidence of colorectal cancer. Identification of important risk factors for advanced colonic tumors could inform both risk stratification and development of risk reduction strategies. Few studies have evaluated risk factors for advanced colorectal tumors in asymptomatic individuals, compared risk factors between persons with and without polyps, or included most purported risk factors in a multivariate analysis.

David A. Lieberman, M.D., of the Department of Veterans Affairs Medical Center, Portland, Ore., and colleagues conducted a study to determine the risk factors associated with advanced colorectal neoplasia (tumors) in a group of asymptomatic persons with complete colonoscopy. The study, conducted between February 1994 and January 1997, included 3,121 asymptomatic patients aged 50 to 75 years from 13 Veterans Affairs medical centers. All participants had complete colonoscopy to determine the prevalence of advanced neoplasia. Variables examined included history of first-degree relative with colorectal cancer, prior cholecystectomy (surgical removal of the gall bladder), serum cholesterol level, physical activity, smoking, alcohol use, and dietary factors.

A total of 329 participants had advanced neoplasia and 1,441 had no polyps. The researchers found positive associations for history of a first-degree relative with colorectal cancer (66 percent increased risk), current smoking (85 percent increased risk), and current moderate to heavy alcohol use and colon neoplasia.

Patients had a lower risk for advanced neoplasia with cereal fiber intake (greater than 4.2 grams/.15 ounces a day), vitamin D intake of greater than 645 IU/d, and daily use of nonsteroidal anti-inflammatory drugs (NSAIDs, 34 percent lower risk). Marginal factors included physical activity, daily multivitamin use, and intake of calcium and fat derived from red meat. No association was found for body mass index, prior cholecystectomy, or serum cholesterol level. Risk variables were similar to those for patients with no polyps, except that past and current smoking were associated with an increased risk of polyps.

" ... it is prudent to recommend that patients stop smoking, reduce alcohol intake, and exercise regularly as part of general preventive health measures," the authors write. "Consuming vitamin D plus a calcium supplement or regular dairy products represents a low-risk strategy that may benefit patients. The benefit of a daily multivitamin is uncertain and requires further study but is associated with very low risk to patients. The strong association with family history of colorectal cancer reinforces existing recommendations to offer screening with colonoscopy. The potential protective effect of NSAIDs must be carefully balanced against the risks. Further study is needed to determine if risk factors at baseline colonoscopy are predictive of future incidence or recurrence of advanced neoplasia." (JAMA. 2003;290:2959-2967. Available post-embargo at jama.com)
-end-
Editor's Note: This study was supported by the Cooperative Studies Program, Department of Veterans Affairs. Co-author Dr. Prindiville was supported in part by a career development award from the Cancer Research Foundation of America and the National Cancer Institute.

The JAMA Network Journals

Related Smoking Articles from Brightsurf:

Smoking rates falling in adults, but stroke survivors' smoking rates remain steady
While the rate of Americans who smoke tobacco has fallen steadily over the last two decades, the rate of stroke survivors who smoke has not changed significantly.

What is your risk from smoking? Your network knows!
A new study from researchers at Penn's Annenberg School for Communication found that most people, smokers and non-smokers alike, were nowhere near accurate in their answers to questions about smoking's health effects.

Want to quit smoking? Partner up
Kicking the habit works best in pairs. That's the main message of a study presented today at EuroPrevent 2019, a scientific congress of the European Society of Cardiology (ESC).

Smoking and mortality in Asia
In this analysis of data from 20 studies conducted in China, Japan, South Korea, Singapore, Taiwan and India with more than 1 million participants, deaths associated with smoking continued to increase among men in Asia grouped by the years in which they were born.

Predictors of successfully quitting smoking among smokers registered at the quit smoking clinic at a public hospital in northeastern Malaysia
In the current issue of Family Medicine and Community Health, Nur Izzati Mohammad et al. consider how cigarette smoking is one of the risk factors leading to noncommunicable diseases such as cardiovascular and respiratory system diseases and cancer.

Restaurant and bar smoking bans do reduce smoking, especially among the highly educated
Smoking risk drops significantly in college graduates when they live near areas that have completely banned smoking in bars and restaurants, according to a new study in the American Journal of Epidemiology.

How the UK smoking ban increased wellbeing
Married women with children reported the largest increase in well-being following the smoking bans in the UK in 2006 and 2007 but there was no comparable increase for married men with children.

Smoking study personalizes treatment
A simple blood test is allowing Vanderbilt University Medical Center (VUMC) researchers to determine which patients should be prescribed varenicline (Chantix) to stop smoking and which patients could do just as well, and avoid side effects, by using a nicotine patch.

A biophysical smoking gun
While much about Alzheimer's disease remains a mystery, scientists do know that part of the disease's progression involves a normal protein called tau, aggregating to form ropelike inclusions within brain cells that eventually strangle the neurons.

A case where smoking helped
A mutation in the hemoglobin of a young woman in Germany was found to cause her mild anemia.

Read More: Smoking News and Smoking Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.