Studies identify risk factors for colon cancer in women

May 19 2004

Every day new research shows major correlations between prevalent diseases in America and leading research is often specific to more targeted populations, such as women. In new studies presented today at Digestive Disease Week in New Orleans, scientists report that women’s preferences for a female physician may delay or prevent proper colorectal screenings due to a lack of females in the field and diabetes may be a significant risk factor for development of colon cancer.

Digestive Disease Week (DDW) is the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery. “Colorectal cancer is the second leading cancer killer in the United States, so barriers to screening and other related challenges need to be addressed to improve care,” said Bernard Levin, M.D., of the University of Texas MD Anderson Cancer Center.

Female patients tend to prefer seeing female physicians in most specialties of medicine. A study presented by researchers at the University of Michigan found that for colorectal screenings in particular, women patients’ preference for a female health care professional is strong enough to delay the procedure and incur additional expenses, as there is a lack of available female endoscopists.

To confirm their hypothesis, researchers administered a questionnaire to a prospective cohort of 202 female patients between the ages of 40 and 70 at four primary care offices. Forty-three percent of the respondents preferred a female endoscopist. Of those, 87 percent were willing to wait more than 30 days for the female and 14 percent were willing to pay additional costs for one.

Five percent of respondents said they would not undergo the procedure unless guaranteed a female endoscopist. Analysis of the questionnaires showed that the preference for a female endoscopist was most often predicted by the gender of the primary care physician, younger patient age and employment status. The sole independent factor associated with adherence to screening was doctor recommendation.

Other barriers to the colonoscopy procedure included dislike of preparation and test (31%) and discomfort (18%). "Colorectal cancer can be treated and lives can be saved if the disease is caught early," according to Stacy Menees, M.D., lead author of the study. "The preferred screening method for identifying colorectal cancer is colonoscopy. Our research shows that seventy-five percent of women report embarrassment as a reason for female gender preference and in five percent of women, not guaranteeing a female endoscopist at the time of a colonoscopy is an absolute barrier to having the procedure performed. Interventions to improve adherence to colorectal screening must address gender preference with women patients." Researchers at the Overton Brooks VA Medical Center in Louisiana have found a strong association between diabetes and the risk of developing colon cancer, according to a conclusive study of more than 50,000 US veterans.

In the retrospective, cross-sectional, case-control study, researchers evaluated the medical records of 60,697 patients between October of 1998 and June 2003 using regression analysis and adjusting for obesity, smoking, use of aspirin and alcohol. The 17.7 percent of patients in the study who had diabetes (8,974 patients) were 32 percent more likely to develop colon cancer than patients without diabetes.

“Given the increasing prevalence of diabetes and the serious mortality associated with colon cancer, we cannot ignore the strong possibility that the two diseases are related in some way and hope to confirm this theory with further study,” said Rambabu Chalasani, M.D., lead author of the study. “However, our results should be viewed with caution due to the limitations of a case-control study and the population in the database.” Duration and degree of control of diabetes was not factored into the analysis and some factors known to increase the risk of colon cancer, such as family history of colon cancer and personal history of inflammatory bowel disease were not incorporated.

However, their effects were limited by the large size of the patient population. The incidence of insulin resistance is rising in the US and colon cancer remains the second leading cause of cancer death. The geographic patterns of the two diseases are extremely similar; both were considered relatively rare before industrialization and the incidence has increased in regions undergoing economic development. Insulin resistance has been associated with hyperinsulinemia, increased levels of growth factors and alterations in receptor signaling, which may promote colon cancer.

http://www.ddw.org/