The ACA’s Impact on Emergency General Surgery Admissions for Complicated Diverticulitis

Author(s):
Paul Albini; Nikolas Kappy; Todd Costantini; Jay Doucet; Laura Haines

Background:

The Affordable Care Act (ACA) expanded access to health insurance for millions. In prior work, the ACA decreased overall need for Emergency General Surgery (EGS) but costs and reported complications increased, with more EGS done at teaching centers.  The effects of the ACA on EGS for complicated diverticulitis (CD) are unknown.

Hypothesis:

We hypothesized that emergency interventions for CD decreased post-ACA, with more CD admissions at teaching hospitals.

Methods:

The National Inpatient Sample (NIS) from 2012 through Q3 of 2015 was used to collect ED admissions for CD, defined as diverticulitis with peritonitis or abscess, in patients aged 18-64. ICD-9 codes were used to identify interventions including open or laparoscopic colectomy, ostomy, or percutaneous abscess drainage. Demographics, length of stay (LOS), hospital type, and Charlson Comorbidity Index (CCI) were obtained. The ACA effect (pre: 2012-2013, post: 2014-Q3/2015) on mortality, complications, and costs was assessed using Difference-in-Differences (DID) analysis.

Results:

A total of 13,909 CD admissions were identified in the unweighted NIS sample. CD admissions increased on average 5.7% annually during the study period with admissions shifting to teaching hospitals post-ACA (44.5% to 60.6%, p<0.001).   Post-ACA, self-payers decreased (17.4% to 11.8%, p<0.001) while Medicaid increased (12.3% to 18.0%, p<0.001) and private insurance did not change. Median LOS decreased post-ACA (6 days to 5 days, p<0.001). Median wage-index adjusted admission costs increased post-ACA ($12.0K to $14.1K, p<0.001).  Post-ACA, the need for surgery was unchanged as was the need for percutaneous drainage only. Overall, admissions with complications increased post-ACA (28.4% to 30.2%, p=0.026).  Complications for surgery were unchanged but were increased for percutaneous drain-only (21.7% to 26.7%, p=0.001).  There was no change in mortality post-ACA.  Adjusted DID analyses for insured vs uninsured admissions showed no significant difference in the rate of change for interventions, complications or costs post-ACA.

Conclusions:

Contrary to our hypothesis, CD admissions increased post-ACA, although the rates of interventions remained similar. Overall costs and complications increased. Teaching hospitals now admit the majority of CD cases, which should drive resource allocation and policy.