Community Need Index (CNI): a simple tool to predict emergency department utilization after hospital discharge from the trauma service

BACKGROUND: Emergency department (ED) visits after hospital discharge may reflect failure of transition of care to the outpatient setting. Reduction of postdischarge ED utilization represents an opportunity for quality improvement and cost reduction. The Community Need Index (CNI) is a Zip code-based score that accounts for a community’s unmet needs with respect to healthcare and is publicly accessible via the internet. The purpose of this study was to determine if patient CNI score is associated with postdischarge ED utilization among hospitalized trauma patients. METHODS: Level 1 trauma patient admitted between January 2014 and June 2016 were stratified by 30-day postdischarge ED utilization (yes/no). CNI is a nationwide Zip code-based score (1.0–5.0) and was determined per patient from the CNI website. Higher scores indicate greater barriers to healthcare per aggregate socioeconomic factors. Patients with 30-day postdischarge ED visits were compared with those without, evaluating for differences in CNI score and clinical and demographic characteristics. RESULTS: 309 of 3245 patients (9.5%) used the ED. The ED utilization group was older (38.3±15.7 vs. 36.3±16.4 years, p=0.034), more injured (Injury Severity Score 10.4±8.7 vs. 7.7±8.0, p<0.001), and more likely to have had in-hospital complications (17.5% vs. 5.4%, p<0.001). Adjusted for patient age, injury severity, gender, race/ethnicity, penetrating versus blunt injury, alcohol above the legal limit, illicit drug use, the presence of one or more complications and comorbidities, hospital length of stay, and insurance category, CNI score ≥4 was associated with increased utilization (OR 2.0 [95% CI 1.4 to 2.9, p<0.001]). DISCUSSION: CNI is an easily accessible score that independently predicts postdischarge ED utilization in trauma patients. Patients with CNI score ≥4 are at significantly increased risk. Targeted intervention concerning discharge planning for these patients represents an opportunity to decrease postdischarge ED utilization. LEVEL OF EVIDENCE: III, Prognostic and Epidemiological.