Surgery for diverticular disease results in a higher hernia rate compared to colorectal cancer: a population-based study from Ontario, Canada.

BACKGROUND: Incisional hernias are a well described complication of abdominal surgery. Previous studies identified malignancy and diverticular disease as risk factors. We compared incisional hernia rates between colon resection for colorectal cancer (CRC) and diverticular disease (DD).

STUDY DESIGN: We performed a retrospective, population-based, matched cohort study. Provincial databases were linked through the Institute for Clinical Evaluative Sciences. These databases include all patients registered under the universal Ontario Health Insurance Plan. Patients aged 18-105 undergoing open colon resection, without ostomy formation between April 1, 2002 and March 31, 2009, were included. We excluded those with previous surgery, hernia, obstruction, and perforation. The primary outcomes were surgery for hernia repair, or diagnosis of hernia in clinic.

RESULTS: We identified 4660 cases of DD. These were matched 2:1 by age and gender to 8933 patients with CRC for a total of 13,593. At 5 years, incisional hernias occurred in 8.3% of patients in the CRC cohort, versus 13.1% of those undergoing surgery for DD. After adjusting for important confounders (comorbidity score, wound infection, age, diabetes, prednisone and chemotherapy), hernias were still more likely in patients with DD [HR 1.58, 95% Confidence Interval (CI) 1.43-1.76, P < 0.001]. The only significant covariate was wound infection (HR 1.63, 95% CI 1.43-1.87, P < 0.001).

CONCLUSION: Our study found that incisional hernias occur more commonly in patients with DD than CRC.