Delay to Intervention for Complicated Diverticulitis is Associated with Higher Inpatient Mortality.

BACKGROUND Patients with diverticular disease complicated by abscess and/or perforation represent the most severely afflicted with the highest mortality and poorest outcomes. This study investigated patient and operative factors associated with poor outcomes from diverticulitis complicated by abscess or perforation. METHODS We analyzed the National Inpatient Sample to identify inpatient discharges for colonic diverticulitis in the United States from 1/1988 to 9/2015. We identified patients with perforation and/or intestinal abscess based on ICD-9 codes. The primary outcome was inpatient mortality. RESULTS During the study period, a total of 993,220 patients were discharged with diverticulitis from sampled U.S. hospitals. From this group, 10.7% had an abscess and 1.0% had a perforation associated with diverticular disease. Inpatient mortality of diverticulitis patients with a perforation was 5.4% compared to 1.5% in those without a perforation (p<0.001). Patients with a perforation who underwent surgery had an inpatient mortality of 6.3% vs. 3.0% mortality amongst patients with a perforation who did not undergo an operation (p<0.001). Patients with a perforation that underwent surgery had a 31% increased mortality risk for each day after admission that a procedure was delayed (OR 1.31, CI 1.05-1.78; p=0.03). Mortality risk was increased for patients with either abscess or perforation who underwent surgery if they were female, age ≥65, higher comorbidity, were admitted urgently, underwent peritoneal lavage, or had a post-procedural complication. CONCLUSIONS Patients with perforated diverticular disease had substantial associated inpatient mortality compared to those with uncomplicated diverticulitis. This increased risk may be associated with performance of peritoneal lavage or because of a delay to procedural intervention.