Brigham and Women's Hospital Boston, Massachusetts
Introduction: In the United States, a small number of patients, labeled as super-utilizers accounts for a disproportionately large fraction of healthcare expenditure. The knowledge about the characteristics of super-utilizers and their impact on healthcare utilization would be helpful to various stakeholders to target interventions aimed at reducing the disproportionate use of the healthcare system.
Methods: We extracted data from the Nationwide readmission Database (NRD) 2019, on patients admitted primarily with a gastrointestinal (GI) pathology. We used Agency for Healthcare Research and Quality’s definition for super-utilizers (2 standard deviations above the average number of hospital stays for patients in each payer category which were ≥4 for Medicaid/Medicare and ≥3 for privately /uninsured in 2019). We collected data on demographics, readmission rates, and hospitalization costs.
Results: Of 1,704,913 patients who were discharged alive, 6.3% were categorized as super-utilizers. The highest proportion of super-utilizers was observed among patients with hepatic failure (19.6%), non-infectious hepatitis (13.6%), and inflammatory bowel disease (10.4%) (Fig 1). On multivariate analysis, several characteristics were independently associated with super-utilizers, especially the comorbidity burden and disease severity (Table 2). The mean number of admissions for an average super-utilizer was ~4 times compared to other patients (mean admissions: 5.5 vs 1.4; p< 0.001). Super-utilizers were mostly admitted for medical diagnosis (83.4% vs 67.3%) as compared to surgical (16.5% vs 31.4%) and for non-elective reasons (92.1% vs 88.9%). The 30-day readmission rate was ~6 times higher among super-utilizers compared to other patients (36.6% vs 6.4% p< 0.001).Compared to other patients, super-utilizers had longer hospital stays (mean days: 5.8 vs 4.4; p< 0.001) and higher average hospitalization costs (mean US$: 15060 vs 13023; p< 0.001). Super-utilizers although only 6.3%, accounted for 31.5% of hospitalization days, 28.2% of costs, 19.6% of hospital stays, and 27.3% of all-cause 30-day readmissions. These findings were consistent across the different payer types on subgroup analysis.
Discussion: 6.3% of patients admitted with a GI diagnosis were classified as super-utilizers. Comorbidity burden and disease severity were strongly associated with super-utilizers. Super-utilizers accounted for a disproportionate share of hospital days, costs, stays, and 30-day readmissions compared to other patients.
