HOSPITAL READMISSION OF CONGENITAL HEART DISEASE PATIENTS IN CANADA

Abstract

Hospital readmissions represent a vast burden on health care resources and in many cases are avoidable. However, little is known about hospital readmission in children or adults with congenital heart disease (CHD) in Canada. We assessed readmission rates among CHD patients stratified by age, sex, and severity of CHD from 2003 to 2012 in Canada and identified risk factors associated with hospital readmission. A retrospective cohort study was conducted among CHD patients identified from the hospital discharge abstract database of the Canadian Institute for Health Information from 2003 to 2012. We identified all index hospitalizations and followed them for up to 12 months to determine the readmission rate. The readmission rate for a given period of time, which is a cumulative outcome, was determined using a Poisson regression model and also stratified by age, sex, and severity of CHD. Multivariable logistic regression analyses were performed to identify risk factors associated with readmission within 2 weeks and 1 month after discharge. The readmission rates per 1,000 CHD patients were 48 within 2 weeks, 83 within 1 month, 163 within 3 months, and 353 within 1 year. More adults were readmitted compared to children (5.4% vs. 4.2% at 2 weeks and 8.5% vs. 7.2% at 1 month). Patients age ≥65 years had a 1.4 to 1.8 times higher readmission rate compared to infants (p<0.001). Among children, infants showed significantly higher readmission rate at 2 weeks (p=0.014), 1 month (p=0.03) and 3 months (p<0.001). The readmission rates were 2.5 to 4.9 times higher in complex CHD patients (p<0.001) and 1.3 to 1.8 times higher in moderate CHD patients (p<0.001) than simple CHD patients. Independent risk factors for readmission within 2 weeks and 1 month were age ≥40 years, age < 1 year, male sex, longer index hospitalization stay, and complex CHD. In adults non-CHD cardiovascular diagnoses (congestive heart failure, atrial fibrillation and flutter, aortic valve disease, ischemic heart disease) were the most common diagnoses associated with hospital readmission while in children ventricular septal defect and respiratory illness were the most common reasons for readmission. Hospital readmission was common in CHD patients, particularly adults aged 40+ years, infants, males and those with complex lesions. Further studies are required to investigate the mechanism for unplanned readmission.