Characteristics of 30-Day All-Cause Hospital Readmissions Among Patients with Acute Pancreatitis and Substance Use

Background/Objectives Previous studies on healthcare resource utilization and 30-day readmission risks among patients with acute pancreatitis (AP) have focused upon opioid and alcohol use. The data on other substance types are lacking. In this study we aim to estimate the 30-day readmission rates, predictors of readmission, impact of readmission on patient outcomes and resulting economic burden among patients with AP and substance use in the USA. Methods This was a retrospective cohort study, based upon data from 2017 National Readmission Database of adult patients with AP and substance use (alcohol in combination, opioid, cannabis, cocaine, sedatives, other stimulants, other hallucinogens, other psychoactive, inhalant and miscellaneous). We estimated the 30-day readmission rates and predictors of 30-day readmission. Results Among 25,795 eligible patients, most were male, belonged to the lower income quartile, resided in the urban facility and had a Charlson comorbidity score of 0 or 1. The use of a combination of substances was the most common in 17,265 (66.9%) patients followed by only opioids in 4691 (18.2%) patients and only marijuana in 3839 (14.9%) patients. A total of 14.6% patients were readmitted within 30 days after discharge for non-elective causes with the highest risk of readmission within the 1st week after discharge with 5.2% readmissions. Among top ten causes of readmission, most of the principal diagnosis were related to AP in 53.1%. Compared to index admission, readmitted patients had significantly higher rates of acute cardiac failure, shock, and higher in-hospital mortality rate. Overall, readmission attributed to an additional 17,801 days of hospitalization resulting in a total of $150 million in hospitalization charges and $36 million in hospitalization costs in 2017. On multivariate analysis, chronic pancreatitis, self-discharge against medical advice, treatment at the highest volume centers, higher Charlson comorbidity index, increasing length of stay and severe disease were associated with higher odds of readmission while female gender and private insurance were associated with lower odds. Conclusion Readmission was associated with higher morbidity and in-hospital mortality among patients with AP and substance use and resulted in a significant monetary burden on the US healthcare system. Several factors identified in this study may be useful for categorizing patients at higher risk of readmission warranting special attention during