Significant underuse of follow-up colonoscopy observed at 5 years after polypectomy

SAN DIEGO — Significant underuse of follow-up colonoscopy was observed at 5 years after polypectomy, which contrasts to an overuse of follow-up colonoscopy in patients without resected polyps, according to data presented at the 2012 Digestive Disease Week Annual Meeting.

While professional society guidelines recommend follow-up colonoscopy in patients with resected colonic adenomas — a procedure which has had longstanding reimbursement under Medicare — patient adherence to these recommendations in clinical practice has not been closely evaluated.

“The focus of our study were patients without diagnosed cancer, but who had an identified history of polyps, and were Medicare beneficiaries, during a time period when Medicare covered routine colonoscopy without going through prior authorization,” Gregory S. Cooper, MD, director of the fellowship program at University Hospitals Case Medical Center in Cleveland, OH, told HemOnc Today. “We were most interested in seeing what the follow-up was because while the recommendations have changed somewhat, but for the most part, patients with a history of adenomous polyps should come back in five years.”

Using data obtained from fee-for-service Medicare claims from a 5% random sample of cancer-free patients residing in one of the geographic areas served by a SEER registry, researchers identified 12,998 patients aged 71 and older with a claim for colonoscopy with polypectomy or hot biopsy from 2001 to 2004. Medicare claims from the previous five years were used to obtain data about previous examinations, and to estimate a comorbidity score.

In addition, subsequent Medicare claims through 2009 were evaluated to identify receipt of colonoscopy within the following five years, as well as other procedures, including barium enema, fecal occult blood test and sigmoidoscopy. The study analysis was limited to patients who survived at least 5 years and patients were censored at the time of the next colonoscopy or five years after the index procedure.

According to the study results, through the end of the five year follow-up, 33.5% of patients received another colonoscopy and 24.2% underwent repeat polypectomy. The researchers observed a marked decrease in repeat colonoscopy at 1, 3 and 5 years with more recent years of index procedures. Predictors of undergoing repeat colonoscopy in this study included younger age, lower comorbidity score, a colonoscopy within 5 years prior to the index procedure and a previous diagnosis of inflammatory bowel disease or carcinoma in situ.

The researchers also observed no clinically significant association with physician specialty, geographic location or small area socioeconomic variables. The decreasing use of colonoscopy with time was maintained in a multivariable analysis (OR 2002: 0.84, 95% CI 0.78-0.91; OR 2003: 0.75, 95% CI 0.69-0.82; OR 0.64, 95% CI 0.58-0.70).

“What we found somewhat disturbing was that there was a decline in the use of follow-up colonoscopy over time,” Cooper said. “We were surprised because when we came into this study, our original hypothesis had been that, if anything, colonscopies would be overused, correlating with other studies that have shown the overuse of colonoscopies in certain populations — patients returning sooner than recommended despite having had nothing identified on prior colonoscopies — but these were patients with an identified history of polyps and only one-third of them were coming back.”

Disclosure: Dr. Kou has an employment position with Merck & Co.

For more information:

Cooper GS. #Tu1178: Underuse of Colonoscopy for Polyp Surveillance in Medicare Beneficiaries. Presented at: the 2012 Digestive Disease Week Annual Meeting; May 19-22, 2012; San Diego.