Illicit Substance Use, Hepatitis C Predicts Infective Endocarditis Readmission

The use of illicit substances and previously diagnosed hepatitis C virus (HCV) infection were found to be significantly predictive of hospital readmission among patients with infective endocarditis (IE), according to results of a study published in American Journal of Cardiology.

Researchers used data captured from the National Readmission Database to explore outcomes associated with substance use among patients hospitalized with IE, as well as factors associated with hospital readmission. The primary outcome was the rate of hospital readmission within 30 days of discharge. Secondary outcomes included predictors of readmission, mortality, and health care-associated costs.

The final analysis comprised 40,413 patients hospitalized with IE, of whom 13.8% were readmitted (mean age, 55±20 years; 44.5% women) and 86.2% were not readmitted (mean age, 61±19 years; 44% women) within 30 days of initial hospitalization. The median cost of IE hospitalization among all patients was $84,325 (range, $39,022-190,492).

Patients who were readmitted had significantly increased rates of HCV infection (19.4% vs 12.6%), end-stage kidney disease (12.2% vs 10.5%), and HIV infection (1.8% vs 1.2%) compared with those who did not require readmission (all P <.001). However, significantly decreased rates of hypertension (56.9% vs 64%; P <.001), heart failure (37.7% vs 40.0%; P <.001), chronic kidney disease (31.2% vs 32%; P <.001), diabetes (27.8% vs 29.4%; P =.01), and peripheral vascular disease (3.6% vs 4.6%; P =.001) were noted among patients who did compared with those who did not require readmission.

The researchers used multivariate logistic regression to determine predictors of hospital readmission, with adjustments for patient age, diabetes, heart failure, hypertension, and end-stage kidney disease. Results showed prior use of opioids (odds ratio [OR], 1.34; 95% CI, 1.23-1.46; P <.001), cocaine (OR, 1.32; 95% CI, 1.17-1.48; P <.001), or other illicit substances (OR, 1.16; 95% CI, 1.04-1.30; P =.008) were significantly associated with an increased readmission risk. In addition, patients with HCV also had a significantly increased risk for readmission (OR, 1.32; 95% CI, 1.21-1.43; P <.001).

Limitations of the study include the use of retrospective data and the inability to confirm the accuracy of IE diagnoses. The researchers also note the inability to determine whether readmissions were due to reasons related to substance use or IE severity.

The researchers conclude, “Identifying modifiable predictors of readmission in patients with IE is important to reduce readmission risk and healthcare costs.”