Abstract 14543: Risk Factors Associated with Implantable Cardioverter-Defibrillator Infection in Medicare Beneficiaries

Abstract

Introduction: Infections of Implantable Cardioverter-defibrillators (ICD) are increasing in frequency and are associated with significant mortality and cost. Understanding patient and procedure characteristics that are associated with higher risk of ICD infection is a pre-requisite for developing effective preventive strategies. Currently there is no accurate risk-stratification tool that has been validated in a large population from diverse practice settings Objectives: To identify risk factors associated with increased odds of infection in a large patient populations receiving ICD therapy.

Methods: ICD-9-CM codes were used to screen the 2007 Inpatient Medicare Standard Analytic File and identified 64,903 admissions for ICD procedures. Regression analysis adjusting for device type, demographics, and 28 comorbidities was used to identify characteristics associated with ICD infection.

Results: The study cohort included 1,855 admissions with an ICD infection (2.86%) and 63,048 without an ICD infection. Patients with ICD infections had higher in-hospital (5.2 vs. 0.7%, P<0.001) and total longer-term mortality (28.4 vs. 15.8%, P<0.001) compared to those without ICD infection. Multivariable regression analysis found CIED infection was significantly associated with male gender (rate ratio (RR) = 1.12 [95%CI 1.01-1.25]), non-white race (RR = 1.16 [1.02-1.32]), age < 65 years (RR = 1.29 [1.10-1.50]), and 7 comorbidities including congestive heart failure (RR = 1.39 [1.27-1.53]), renal failure (RR = 1.63 [1.46-1.83]), fluid and electrolyte disorders (RR = 1.69 [1.49-1.92], coagulopathy (RR = 1.81 [1.49-2.20]), blood loss anemia (RR = 1.91 [1.28-2.84]), weight loss (RR = 3.04 [2.35-3.92]), and AIDS (RR = 2.63 [1.22-5.70]). Single or dual chamber ICDs were associated with a higher risk of infection than biventricular pacemakers with a defibrillator (RR = 1.15 [95%CI 1.04-1.26]).

Conclusions: Analysis of this large Medicare Beneficiary population, receiving ICD therapy in diverse practice settings, identified 3 demographic features and 7 ICD-9-CM-coded comorbidities that are associated with an increased risk of ICD infection.