Abstract 18723: Socioeconomic Disparities and Burden of Sudden Cardiac Arrest in Metropolitan Areas: A USA-Canada Comparative Analysis
Introduction: Low socioeconomic status (SES) is associated with poor cardiovascular outcomes and may be a determinant of sudden cardiac arrest (SCA) incidence.
Objective: We evaluated the association between SES and SCA incidence from seven sites in the Resuscitation Outcomes Consortium (ROC) Epistry, a registry of all out-of-hospital cardiac arrests assessed by emergency medical services personnel, and tested whether the relationship differed between the US and Canada.
Methods: Cases were primary cardiac arrests occurring in a residence in Dallas, Pittsburgh, Portland, and Seattle-King County ROC sites (US); and Ottawa, Toronto, and Vancouver sites (Canada), 4/1/2006 - 3/31/2007. Each case was linked to the census tract in which the arrest occurred. Census tracts were classified into quartiles of median income, and incidence per quartile was calculated using all SCAs occurring in census tracts in that quartile (numerator), and the population of all census tracts in that quartile (denominator). Poisson regression was used to estimate and compare SCA incidence rate ratios (IRRs) in the lowest vs. highest quartile of SES.
Results: Across the 9,235 total SCAs (range 638-2,586 per site; mean ages 64-70 years; males 58-65%), incidence was nearly double in the lowest vs. highest SES quartile (IRR 1.9 [95% CI 1.8-2.0]). This disparity was stronger in those <65 years of age (IRR 2.7 [2.5-3.0]) vs. those ≥65 (IRR 1.3 [1.2-1.4]). For all ages combined, Canadian sites had less disparity across SES quartiles (IRR 2.0 [1.9-2.2]) for US sites; (IRR 1.8 [1.6-2.0]) for Canadian sites. For ages <65, this disparity was more pronounced (IRR 3.0 [2.7-3.50]) for US sites; (IRR 2.3 [2.0-2.7]) for Canadian sites. The magnitude of the association between SES and SCA incidence was larger in the US than in Canada (p<0.001 for interaction), adjusting for site and census tract population age structure.
Conclusions: SCA incidence was consistently higher in poorer neighborhoods of North American metropolitan areas, though this relationship was attenuated in Canadian cities. These findings underscore the important association of SES with SCA incidence, also suggesting that fundamental differences between the two countries may contribute to the greater adverse impact of SES in the US.
- © 2010 by American Heart Association, Inc.