Skip Navigation U.S. Department of Health and Human Services
Agency for Healthcare Research Quality
Archive print banner


This information is for reference purposes only. It was current when produced and may now be outdated. Archive material is no longer maintained, and some links may not work. Persons with disabilities having difficulty accessing this information should contact us at: Let us know the nature of the problem, the Web address of what you want, and your contact information.

Please go to for current information.

Researchers assess optimal timing of surgery following one or more attacks of uncomplicated diverticulitis

Twenty-five to thirty percent of people who have an attack of diverticulitis will have another one within 5 years. These attacks, caused by inflammation of one or more diverticula (pouchlike herniations through the muscular layer of the colon), cause cramping pain over the colon and fever. Severe attacks can involve an abscess in the tissues surrounding the colon, which can become obstructed, requiring urgent surgery and sometimes colostomy (surgical creation of an opening between the colon and skin surface).

Most authorities recommend prophylactic bowel surgery of the affected areas after two established attacks in order to reduce the risk of further attacks. However, waiting to perform this surgery after a third uncomplicated attack is more cost-effective, concludes a study supported by the Agency for Healthcare Research and Quality (HS10827).

Robert J. Richards, M.D., M.S., of the University of Kansas Medical Center, and James K. Hammitt, Ph.D., of the Harvard School of Public Health, used a decision model to compare the costs and outcomes of performing surgery after one, two, or three uncomplicated diverticulitis attacks (resolve with conservative treatment such as antibiotics, bed rest, and intravenous fluids) in a hypothetical group of 60-year-old men and women. They estimated costs from Medicare reimbursement rates and estimated a 5-year recurrence rate of 26 percent based on previous studies.

Surgery following a second attack of diverticulitis did not increase life expectancy or quality-adjusted life years (QALYs), but it did increase costs considerably. On average, waiting until after the third attack cost $2,500, yielding 14 years of life expectancy and 14 QALYs, which was far more cost-saving than the other two options. Only when the yearly risk of having an outpatient recurrence was 42 percent did prophylactic surgery after the first attack exceed option three in terms of life expectancy and QALYs. However, the incremental cost per QALY saved was $4,500,000. The model results did not change until the 5-year risk for the third attack equaled 61 percent. Only at this point, was option 2 (surgery following the second attack) the preferred strategy at a cost of $95,000 per additional QALY saved.

More details are in "Timing of prophylactic surgery in prevention of diverticulitis recurrence: A cost-effectiveness analysis," by Drs. Richards and Hammitt, in the September 2002 Digestive Diseases and Sciences 47(9), pp. 1903-1908.

Return to Contents
Proceed to Next Article

The information on this page is archived and provided for reference purposes only.


AHRQ Advancing Excellence in Health Care