Study: Bowel Perforation Rate Higher During Colonoscopy

The risk of perforation of the bowel during a colonoscopy declined during the 1990s but remains higher than the risk of perforation during a sigmoidoscopy, according to a report in the Journal of the National Cancer Institute.

A colonoscopy is used to check the entire length of the colon for cancer or precancerous abnormalities, while a similar technique called sigmoidoscopy is limited to the section of the colon closest to the rectum. A potential complication from both procedures is perforation, or damage to the colon wall.

Columbia University researchers used a database of Medicare beneficiaries to identify people who underwent at least one colonoscopy or sigmoidoscopy between 1991 and 1998, and then calculated the incidence and risk of perforation.

Of 39,286 colonoscopies included in the analysis, there were 77 perforations (1.96 perforations per 1,000 colonoscopies), compared with 31 perforations in 35,298 sigmoidoscopies (0.88 perforations per 1,000 sigmoidoscopies).

"The two procedures [were] much more similar in overall risk at the end of the study period than they had been at the beginning," the researchers reported. They suggested that the decline in colonoscopy perforations may have resulted from improvements in technology and training.

The researchers found that about 5 percent of those who suffered a perforation died within 14 days of the procedure.

"The risk of perforation after colonoscopy is approximately double that after sigmoidoscopy, but this difference appears to be decreasing," the researchers concluded.

Other Sources: Journal of the National Cancer Institute