Colonoscopy may be more frequent than recommended in Medicare patients

Medicare patients may be receiving colonoscopies more frequently than recommended by guidelines, according to a new study.

Expert guidelines recommend that colonoscopy be performed every 10 years in patients with normal findings on initial screening colonoscopy. Researchers studied a 5% national sample of Medicare patients from 2000 to 2008 to examine how frequently colonoscopy was repeated after a negative screening test. Colonoscopy was considered to be a negative screening examination if Medicare claims indicated only screening and if no follow-up procedure, such as a biopsy, fulguration or polypectomy, was done. Included patients were of average risk for colon cancer and had had screening colonoscopy between 2001 and 2003. The study results were published early online May 9 by Archives of Internal Medicine.

In the sample studied, 24,071 Medicare patients had a negative screening colonoscopy from 2001 to 2003. Of these, 46.2% had repeated colonoscopy in the next seven years, and of this group, 42.5% had no clear indication for early testing. Of patients who were 75 to 79 years old or at least 80 years old at the initial negative screening, 45.6% and 32.9%, respectively, had another colonoscopy within seven years.

Multivariable analyses found that patients who were male, had more comorbid conditions, and had colonoscopies performed by a high-volume colonoscopist or in an office were more likely to have early repeated tests without clear indications, while such testing was less likely in patients who were age 80 and older. Rates of early colonoscopy also varied widely by region.

The authors noted that their study was limited because information was not available on the quality of the first colonoscopy and because their results may not be generalizable to patients younger than 66 years of age or those covered by HMOs. However, they concluded that many Medicare patients receive screening colonoscopy more frequently than guidelines recommend. They pointed out that one-third of patients age 80 and older underwent screening colonoscopy without a clear indication, which is of concern because complications are more likely in older patients and they benefit less from the test. Older patients who had at least three comorbid conditions and were also therefore less likely to benefit from early removal of precancerous polyps were also more likely to be tested early.

The authors recommended that their analyses be applied to all Medicare data to help identify patterns of overuse and trigger chart audits. They also called for more patient involvement. “Given the increasing public interest in and ownership of cancer screening, public information campaigns that emphasize both the necessity for [colorectal cancer] screening as well as the dangers of overuse may prove beneficial in reducing overuse,” they wrote.