Factors Associated With Readmission in the United States Following Hospitalization With Coronavirus Disease 2019.

Background: Patients hospitalized for coronavirus disease 2019 (COVID-19) may experience complications following hospitalization and require readmission. In this analysis, we estimated the rate and risk factors associated with COVID-19-related readmission and inpatient mortality.

Methods: In this retrospective cohort study, we used deidentified chargemaster data from 297 hospitals across 40 US states on patients hospitalized with COVID-19 from 15 February 2020 through 9 June 2020. Demographics, comorbidities, acute conditions, and clinical characteristics of first hospitalization are summarized. Multivariable logistic regression was used to measure risk factor associations with 30-day readmission and in-hospital mortality.

Results: Among 29 659 patients, 1070 (3.6%) were readmitted. Readmitted patients were more likely to have diabetes, hypertension, cardiovascular disease (CVD), or chronic kidney disease (CKD) vs those not readmitted (P < .0001) and to present on first admission with acute kidney injury (15.6% vs 9.2%), congestive heart failure (6.4% vs 2.4%), or cardiomyopathy (2.1% vs 0.8%) (P < .0001). Higher odds of readmission were observed in patients aged >60 vs 18-40 years (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.48-2.50) and those admitted in the Northeast vs West (OR, 1.43; 95% CI, 1.14-1.79) or South (OR, 1.28; 95% CI, 1.11-1.49). Comorbidities including diabetes (OR, 1.34; 95% CI, 1.12-1.60), CVD (OR, 1.46; 95% CI, 1.23-1.72), CKD stage 1-5 (OR, 1.51; 95% CI, 1.25-1.81), and CKD stage 5 (OR, 2.27; 95% CI, 1.81-2.86) were associated with higher odds of readmission; 12.3% of readmitted patients died during second hospitalization.

Conclusions: Among this large US population of patients hospitalized with COVID-19, readmission was associated with certain comorbidities and acute conditions during first hospitalization. These findings may inform strategies to mitigate risks of readmission due to COVID-19 complications.