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Serious Complications of Colonoscopy Are Not Rare

Colonoscopy with biopsy was associated with increased risk for complications.

Because colonoscopy is a widely recommended screening test, precise population-based data on complications are important. To identify serious complications, investigators at Northern California Kaiser Permanente health system reviewed electronic records of 16,318 colonoscopies performed from 1994 to 2002 in patients aged 40 or older. Colonoscopies performed for symptoms were excluded. Complications (bleeding, perforation, diverticulitis, other) were identified by hospital admission or death within 30 days of the procedure and were further evaluated by detailed chart review.

The most common indications for colonoscopy were polyps seen on sigmoidoscopy (45%, with nearly all involving biopsy) and history of polyps (23%, with half involving biopsy); only 0.7% were primary screening tests. The overall incidence of serious complications was 5 per 1000. Among 5235 colonoscopies that did not involve biopsies, the incidence of serious complications was 0.8 per 1000; the incidence of perforations was 0.6 per 1000. Among 11,083 colonoscopies that involved biopsies, the incidence of serious complications was 7.0 per 1000; the incidence of bleeding was 4.8 per 1000 (1.4 for bleeding requiring surgery or transfusion), and the incidence of perforation was 1.1 per 1000. The risk for perforation was higher in patients aged 60 and older. Overall, 40% of all serious complications and 62% of bleeding episodes occurred after removal of polyps smaller than 10 mm.

Comment: An incidence of serious complications of about 1 in 200 is not small for a preventive procedure done in an asymptomatic population. The main limitation of this study is that the results do not apply to complications associated with colonoscopy as a primary screening tool, because so few procedures were done for this purpose. Nevertheless, we need to reduce the risks associated with colonoscopy as we await safer accurate screening tests for colorectal cancer. Patients and physicians should consider these risks when balancing the benefits of colonoscopy against the lower risks associated with other screening tests.

— Richard Saitz, MD, MPH, FACP, FASAM

Published in Journal Watch General Medicine January 16, 2007

Citation(s):

Levin TR et al. Complications of colonoscopy in an integrated health care delivery system. Ann Intern Med 2006 Dec 19; 145:880-6.

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• colonoscopy
  owen w. beem, ret., 22 Apr 2009 6:24 PM EST
  is there anystudies that show that a colonoscopy can bring on a divascolitis attact. coincidentally i had one shortly after... [more]
• severe bloating distention after colonoscopy
  debra l Driscoll, 4 May 2009 3:06 PM EST
  I had a colonoscopy in July of 2008. I have been sick ever since with nausea, vomiting, vertigo, a dull... [more]