Colonoscopy Risks Increase With Age and Illness

June 16 -- MONDAY, June 15 (HealthDay News) -- Screening colonoscopies for colon cancer may be too risky for some elderly patients, a new study finds.

Of all the screening methods for colon cancer, a colonoscopy is considered the gold standard because it not only finds, but also removes, cancerous and precancerous lesions. However, risks such as bleeding, colon perforation and heart problems, while low, may outweigh the benefits for some elderly patients.

"Overall, the risks from colonoscopy are quite low," said lead researcher Joan L. Warren, of the Applied Research Program at the U.S. National Cancer Institute. "However, there are some groups of people for whom the risk was significantly elevated."

They are older people and those with a history of stroke, diabetes, heart failure and atrial fibrillation, Warren said. "For people 85 and over, risk is more than twice that of people 66 to 69. For people 80 and over, the risk is about 50 percent greater," she said.

Older adults with these risk factors need to evaluate the risk of screening colonoscopy against their life expectancy, Warren said.

Colon cancer screening is important for identifying the disease in its earliest, most treatable stages. For people with risk factors for a colonoscopy, Warren suggests less-invasive tests such as the fecal occult blood test.

"Somebody who is older and not in great health might benefit from a fecal occult blood test, and if the result is positive then a colonoscopy may be needed," she said.

The report is published in the June 16 issue of the Annals of Internal Medicine.

For the study, Warren's team collected data on 53,220 Medicare recipients who had colonoscopies between July 2001 and October 2005. The researchers compared these patients with a matched set of Medicare beneficiaries who did not have colonoscopies.

The researchers looked for claims made to Medicare for bleeding, perforation of the colon and heart problems resulting from the procedure.

Warren's group found that those undergoing colonoscopy had a greater risk of adverse events than those who did not have the procedure. The rates of these problems increased with age, the researchers noted.