Abstract 16088: Association of Cumulative ICD Implantations With Decreasing Overall Incidence of Out-of-Hospital Cardiac Arrest
Background: Few studies have examined rates of out-of-hospital cardiac arrest (OHCA) in the era of widespread use of implantable cardioverter-defibrillators (ICD) for primary prevention of sudden death.
Methods: Using Healthcare Cost and Utilization Project data, which captures >95% of California hospitalizations, we identified patients ≥ 18 years of age who received inpatient care between 1/1/2005 and 12/31/2009. OHCA was defined by admissions through the emergency department (ED) for VF (ICD-9 427.4) or cardiac arrest (427.5); inpatient arrests and cases of primary trauma and sepsis were excluded. We identified all comorbidities and new ICD implants using ICD-9 CM and CPT codes. Poisson regression models with robust standard errors were used to evaluate trends.
Results: We identified 117,397 OHCA ED admissions between 2005 and 2009. Cumulative ICD implantations increased by 63,299 over the study period, and were associated with a decrease in OHCA incidence by 6.8 per 10,000 ICDs placed (95% CI 5.8-7.9, P<0.001). The population-adjusted OHCA incidence decreased from a mean of 106/100,000 PY in 2005 to 75/100,000 PY in 2009, a yearly decrease in OHCA incidence of 8.5 cases per 100,000 person-years (PY) (95% CI 7.2-9.8, P<0.001). Significant seasonal effects were observed, with fewer OHCAs in the summer and spring vs. winter (-10.7 and -9.1 per 100,000 PY, both p<0.01) in the context of overall decrease in OHCA incidence between 2005-09. In contrast, over the same 5-year period, admissions for CHF, atrial fibrillation (AF), and COPD all increased (mean yearly increase 32.3, 56.9, and 11.4 per 100,000 PY, respectively; P<0.001 for each).
Conclusions: While admissions for AF, CHF, and COPD have all increased, the rate of OHCA has significantly decreased between 2005-09 and is associated with the large increase in ICDs in use during this time, suggesting a prevention of nearly 7 OHCAs per 10,000 ICDs implanted.
- © 2013 by American Heart Association, Inc.