TUESDAY, May 17 (HealthDay News) -- Obese patients are at a significantly increased risk for surgical site infections after undergoing partial or full removal of the colon, a new study finds.

It included 7,020 patients, aged 18 to 64, who had either partial or total colectomy for colon cancer, diverticulitis or inflammatory bowel disease between 2002 and 2008. Of those patients, 1,243 were obese.

The overall rate of surgical site infections was 10.3 percent, but the rate was higher in obese patients (14.5 percent) than in non-obese patients (9.5 percent). After adjusting for a number of factors, the researchers calculated that obese patients were 60 percent more likely to develop surgical site infections than non-obese patients.

The average cost of colectomy for all the patients was $16,399, but the average cost for obese patients was about $295 more than for non-obese patients.

The researchers also found that surgical site infections greatly increased the cost of the procedure. The average total cost for patients who developed surgical site infections was $31,933, compared to $14,608 for patients without infection.

Patients with surgical site infections also had longer average hospital stays (9.5 days vs. 8.1 days) and a much higher rate of hospital readmission (27.8 percent vs. 6.8 percent).

"We conclude that patients undergoing colorectal surgery who develop SSIs [surgical site infections], many of whom are obese, tax the health-care system," wrote Dr. Elizabeth C. Wick, of the Johns Hopkins School of Medicine in Baltimore, and colleagues.

Incentive programs that reward surgeons for keeping costs down and improving patient outcomes should take into account that obese people are at higher risk of infection, according to the authors.

The study appears in the May issue of the Archives of Surgery.

More information

The University of Chicago Medical Center has more about colectomy.