Objectives: While lower socioeconomic status is associated with lower level of education and increased incidence of cardiovascular diseases, the impact of socioeconomic status on out-of-hospital cardiac arrest outcomes is unclear. We used residential property values as a proxy for socioeconomic status to determine if there was an association with: (1) bystander CPR rates and (2) survival to hospital discharge for out-of-hospital cardiac arrest.
Methods: We performed a secondary data analysis of cardiac arrest cases prospectively collected as part of the Ontario Prehospital Advanced Life Support study, conducted in 20 cities with ALS and BLS-D paramedics. We measured patient and system characteristics for cardiac arrests of cardiac origin, not witnessed by EMS, occurring in a single residential dwelling. We obtained property values from the Municipal Property Assessment Corporation. Analyses included descriptive statistics with 95% CIs and stepwise logistic regression.
Results: Three thousand six hundred cardiac arrest cases met our inclusion criteria between 1 January 1995 and 31 December 1999. Patient characteristics were: mean age 69.2, male 67.8%, witnessed 44.7%, bystander CPR 13.2%, VF/VT 33.8%, time to vehicle stop 5:36min:s, return of spontaneous circulation 12.7%, and survival 2.7%. Median property value was $184,000 (range $25,500-2,494,000). For each $100,000 increment in property value, the likelihood of receiving bystander CPR increased (OR=1.07; 95% CI 1.01-1.14; p=0.03) and survival decreased (OR=0.77; 95% CI 0.61-0.97; p=0.03).
Conclusions: This is the largest study showing an association between socioeconomic status and survival, and the first study showing an association with bystander CPR. Our findings suggest targeting CPR training among lower socioeconomic groups.