The Impact of Obesity on Mortality and Clinical Outcomes in Patients with Acute Diverticulitis in the United States

Background and Aims: Diverticular disease represents a leading cause of gastrointestinal-related hospitalizations. We sought to identify the adverse consequences of obesity on acute diverticulitis (AD) hospital admissions. By age 85, approximately two-thirds of individuals will develop diverticular disease and up to 25% will develop AD. Generally, obesity confers an increased risk of morbidity and mortality; however, its impact on hospitalized patients with AD are lacking. Methods: Utilizing ICD-9-CM codes from the National Inpatient Sample (January 2012 – October 2015) we identified patients with a primary discharge diagnosis of AD including 660,820 hospitalizations and 115,785 with obesity. Primary outcomes were mortality, length of stay, and hospitalization cost. Secondary outcomes were AD complications and the need for surgical interventions. Results: On multivariate analysis, obesity was not associated with an increased risk of mortality (OR=1.1, 95%CI: 0.87-1.41; p= 0.43). However, morbid obesity (BMI > 40 kg/m2) showed a significant increased risk of mortality (OR=1.69, 95%CI: 1.23-2.31; p<0.001). Obesity was associated with prolonged hospitalizations length of stay by 0.61 days (0.55-0.68; p <10-6), higher hospital charges $6,320 ($ 5,500-7,140; p<10-6), increased complicated diverticulitis 1.05 (1.01-1.1; p < 0.010) and required more surgical interventions for diverticulitis (OR=1.19, 95%CI: 1.15-1.23; p<10-6). Conclusion: Morbid obesity increases risk for mortality while obesity leads to longer hospitalization stays and greater healthcare cost as well as adverse clinical outcomes and more surgical interventions. Further interventions are required to address obesity and weight loss for patients with diverticulitis to improve clinical outcomes.