Higher mortality in surgically managed diverticulitis is associated with Asian Ethnicity and right-sided disease

BACKGROUND: Although right-sided diverticulitis is perceived to have a higher incidence among Asians and infrequently requires surgical management in comparison with sigmoid diverticulitis, it is unknown whether differences in outcomes are due to ethnic disparity or disease pathophysiology. OBJECTIVE: The aim of this study was to determine the surgical outcomes for Asian and non-Asian patients with diverticulitis who underwent colectomy. DESIGN: Patients identifiable by ethnicity in the Nationwide Inpatient Sample with diverticulitis and colectomy between 2004 and 2010 were included. Univariate comparisons were made between Asian and non-Asian patients by using t tests for continuous variables and χ² tests for categorical variables. Propensity score matching analysis was performed to compare Asian patients with otherwise similar non-Asian patients. PATIENTS: Included were 58,142 non-Asian and 335 Asian patients with diverticulitis who underwent a colectomy. MAIN OUTCOME MEASURES: The primary outcomes were in-hospital mortality, hospital length of stay, and total costs. RESULTS: Asian patients were younger (56.1 vs 59.2 years, p < 0.0001), were more likely to undergo a right colectomy (22.7% vs 4.1%, p < 0.0001), and were more likely to have emergent/urgent surgery than the non-Asian patients (67.1% vs 49.8%, p < 0.0001). Without controlling for patient/disease factors, there were statistically significant differences in mortality (non-Asian 2.2% vs Asian 4.2%; p = 0.014), length of stay (non-Asian 8.9 vs Asian 9.8 days; p = 0.0166), and costs (non-Asian $18,783 vs Asian $21,901; p = 0.001). Propensity score matching comparing 333 non-Asian patients with 333 similar Asian patients showed that, whereas differences in cost and length of stay became insignificant, the difference in mortality remained statistically significant. LIMITATIONS: The ethnicity variable was not uniformly collected by all states within the Nationwide Inpatient Sample database. CONCLUSIONS: Among patients undergoing a colectomy for diverticulitis, a higher mortality was observed in Asian patients and right-sided disease. Future longitudinal studies comparing the natural history and outcomes of management between right- and left-sided diverticulitis are necessary to investigate whether a true ethnic disparity exists.