The Longer the Colonoscopy Takes, the Better

A new study reveals that polyp and adenoma detection rates were highest when the colonoscopy withdrawal time was nine minutes long.

Researchers at the Norris Cotton Cancer Center (Lebanon, NH, USA) used data from the New Hampshire Colonoscopy Registry to examine how withdrawal time in normal colonoscopies affected adenoma and polyp detection rates. A total of 7,996 colonoscopies performed in 7,972 patients, performed between 2009 and 2011 by 42 endoscopists at 14 hospitals, ambulatory surgery centers, and community practices were analyzed for associations between increased normal withdrawal time and polyp, adenoma, and clinically significant serrated polyp (CSSP) detection rates, based on median endoscopist withdrawal time.

The results showed that detection rates were highest among endoscopists with 9 minute median normal withdrawal time, and detection of CSSPs reached its highest levels at 8–9 minutes. Incident rate ratios for adenoma and CSSP detection increased with each minute of normal withdrawal time above 6 minutes, with maximum benefit at 9 minutes for adenomas and CSSPs. When modeling was used to set the minimum withdrawal time at 9 minutes, the increase in detection was most striking for the CSSPs, with nearly a 30% relative increase. The study was published early online on January 7, 2014, in the American Journal of Gastroenterology.

“Our investigation demonstrates a statistically significant correlation between longer normal withdrawal time and higher polyp detection rates, adenoma detection rates, and serrated polyp detection rates,” concluded lead author Lynn Butterly, MD, and colleagues. “It provides strong evidence to support a 9-minute median normal withdrawal time as a quality standard.”

Related Links:
Norris Cotton Cancer Center