Impact of Substance Use Disorder on Midterm Mortality After Valve Surgery for Endocarditis

Abstract

Fueled by the burgeoning opioid epidemic, valve surgeries for substance use disorder-related infective endocarditis (SUD-IE) are increasing. The impact of substance use disorder on postvalve replacement morbidity needs further investigation. We queried The Society of Thoracic Surgeons Adult Cardiac Surgery Database for all valve surgeries for infective endocarditis at Tufts Medical Center (2002-2016) and collected demographic and disease-related data, including timing of mortality subclassified as short-term (<6 months including operative), midterm (6 months to 5 years), and extended-term (>5 years). Patients with documentation of illicit drug use before the operation were considered to have SUD-IE. Deaths were confirmed through review of medical record and matching with the Massachusetts Vital Statistics Database. We performed univariate and multivariate proportional hazard regressions examining the impact of substance use disorder mortality in people who received a valve replacement. In the cohort of 228 patients, 80 (35%) had SUD-IE. Eight-six people (38%) died, and overall mortality was higher in people with SUD-IE compared with non-SUD-IE (48% vs 32%, P= .025). SUD-IE was associated with a higher risk of overall mortality (adjusted hazard ratio, 2.41; 95% confidence interval, 1.38-4.20; P= .002). Although the difference between short-term or extended-term mortality wasnot significant, SUD-IE was associated with increased frequency of midterm mortality (53% vs 31%, P= .003). Our data reflect high rates of postvalve surgery morbidity and mortality in people with SUD-IE at a tertiary care center. The midterm postoperative period is a vulnerable period for people with SUD-IE worthy of further investigation.