Risk Factors Associated with Readmission after COVID-19 Hospitalization

After an initial hospitalization for COVID-19, some patients may have specific risk factors that increase their likelihood of readmittance.

Even after being cleared, hospitalized COVID-19 patients are not uncommonly readmitted.

In collaboration with Ascension St. John Hospital in Detroit, MI, investigators looked to identify risk factors for readmission after COVID-19 hospitalization.

They conducted a historical cohort study, including COVID-19 cases diagnosed via PCR testing from March 8-June 14, 2020. The study included 391 patients who survived initial hospitalization for COVID-19, and subsequently identified patients readmitted within 30 days of their release.

Investigators used the electronic medical record to collect demographic and clinical data, which were analyzed using Student’s t-test, the chi-squared test, and multivariable logistic regression.

The readmission rate was 13.3% (52 of 391 readmitted). The average time to readmission was 9.2 (± 7.9) days. The average age of the readmitted patients was 66.3 (± 18.6) years; the average age of patients not readmitted was 61 (± 16) years. 44.2% were male, and 78.8% were Black/African American. The most common symptom among the readmitted was shortness of breath (50%). The most frequent diagnosis for readmission was infectious process (57.7%).

Investigators also found that a need for ICU admission or mechanical ventilation during a patient’s initial hospitalization did not increase the risk of readmission. Readmitted patients had a higher prevalence of comorbidities, specifically heart failure and renal disease. Elevated alanine aminotransferase (AST) and/or low albumin level were also correlated with readmission. Of those readmitted, the mortality rate was 11.5%.

The multivariable analysis showed independent predictors of 30-day readmission, including higher Charlson score (p=0.004), higher creatinine on admission in the index hospitalization (p=0.009), and presence of rhabdomyolysis during the index hospitalization (p=0.039).

Of the patients readmitted, infectious etiologies were common. The independent predictors of hospital readmission within 30 days speak for themselves, but the investigators recommended further study into contributing risk factors.