Identification of the risk factors for colorectal neoplasia may help in risk reduction.
In this study, physicians from the United States determined the risk factors associated with advanced colorectal neoplasia in a cohort of asymptomatic individuals.
The team recruited 3121 asymptomatic patients (aged 50 to 75 years) from 13 medical centers.
|Family history, smoking, and alcohol use are risk factors associated with advanced neoplasia.|
|Journal of the American Medical Association|
All participants underwent complete colonoscopy to determine the prevalence of advanced neoplasia. This was defined as an adenoma that was ≥10 mm, a villous adenoma, an adenoma with high-grade dysplasia, or invasive cancer.
The physicians collected data on history of first-degree relative with colorectal cancer, prior cholecystectomy, serum cholesterol level, physical activity, smoking, alcohol use, and dietary factors.
They performed an age-adjusted analysis to calculate the odds ratios (ORs) of having advanced neoplasia, compared with having no polyps.
They also developed a multivariate logistic regression model to identify the most informative risk factors.
A secondary analysis examined risk factors for having hyperplastic polyps, compared with having no polyps, and compared with having advanced neoplasia.
The physicians found that 329 participants had advanced neoplasia, while 1441 had no polyps.
They identified that a first-degree relative with colorectal cancer (OR, 1.66), current smoking (OR, 1.85), and current moderate to heavy alcohol use (OR, 1.02) as risk factors associated with advanced neoplasia.
However, cereal fiber intake (OR, 0.95), vitamin D intake (OR, 0.94), and use of nonsteroidal anti-inflammatory drugs (NSAIDs) (OR, 0.66) were inversely associated.
Marginal factors included physical activity, daily multivitamin use, and intake of calcium and fat derived from red meat.
The team did not identify any association for body mass index, prior cholecystectomy, or serum cholesterol level.
In addition, 391 patients had hyperplastic polyps found at colonoscopy.
Risk variables were similar to those for patients with no polyps.
Dr David Lieberman's team concluded, "Our data endorse several important risk factors for advanced colonic neoplasia and provide a rationale for prudent risk reduction strategies".
"Further study is needed to determine if lifestyle changes can moderate the risk of colorectal cancer".