# Unplanned 30-Day Readmissions After Hospitalization for Irritable Bowel Syndrome

## TL;DR

This study finds that about 11% of patients hospitalized for irritable bowel syndrome are readmitted within 30 days, with higher costs and worse outcomes.

## Contribution

The study identifies specific risk factors and outcomes for unplanned 30-day readmissions in IBS patients using a national database.

## Key findings

- 11.1% of IBS patients were readmitted within 30 days, with higher comorbidities and costs.
- Ulcerative colitis, interstitial cystitis, and peripheral vascular disease increase readmission risk.
- Readmissions had longer hospital stays and higher mortality compared to initial admissions.

## Abstract

Background

Irritable bowel syndrome (IBS) continues to pose significant healthcare challenges due to its broad differential diagnosis and the often extensive yet inconclusive workup. We investigated the rates and characteristics of unplanned 30-day readmissions in adult patients hospitalized with IBS. In addition, we identified factors that predict readmission within 30 days of initial discharge.

Methods

We analyzed the 2020 Nationwide Readmission Database. Using the International Classification of Diseases, Tenth Revision, Clinical Modification code, we identified hospitalizations in adult patients with IBS. We excluded hospitalizations for minors and planned or elective readmissions. To compare baseline characteristics between readmissions and index hospitalizations, χ2 tests were employed. We used multivariate Cox regression analyses to identify independent predictors of readmissions.

Results

A total of 5,729 adult hospitalizations with IBS as the primary diagnosis were discharged alive, and 638 (11.1%) readmissions occurred within 30 days. The most common diagnoses associated with readmission were noninfective gastroenteritis and colitis, sepsis, enterocolitis due to Clostridium difficile, and irritable bowel syndrome with or without diarrhea. Patients in readmissions had a mean age of 56.3 years, similar to index hospitalizations (54.5 years, p=0.093). Readmissions had a higher burden of comorbidity (Charlson comorbidity index (CMI) scores ≥3: 26.7%, 170 cases vs. 16.6%, 953 cases; p<0.001) and were mostly Medicare beneficiaries (49.5%, 316% vs. 44.9%, 2,578) compared with index hospitalizations. Readmissions had a longer mean length of stay (LOS) (5.2 vs. 3.6 days, p<0.0001), higher inpatient mortality (0.8%, 5% vs. 0.2%, 11; p=0.032), and higher mean hospital costs ($47,852 vs. $34,592; p<0.0001) compared with index admissions. Secondary diagnoses of ulcerative colitis (adjusted hazard ratio (AHR), 2.82; p<0.0001), interstitial cystitis (AHR, 5.37; p=0.007), peripheral vascular disease (AHR, 1.59; p=0.027), and discharge to short-term hospitals (AHR, 1.03; p<0.0001) were significantly associated with a higher likelihood of readmission within 30 days.

Conclusion

IBS readmissions have poorer outcomes than index hospitalizations. Patients with an existing history of ulcerative colitis, interstitial cystitis, and peripheral vascular disease and those discharged to short-term hospitals following index hospitalization are more likely to be readmitted within 30 days.