(P122) INCIDENCE AND OUTCOMES OF OUT-OF-HOSPITAL CARDIAC ARREST PATIENTS ADMITTED TO THE HOSPITAL: A POPULATION-BASED RETROSPECTIVE COHORT STUDY IN CANADA FROM 2013 TO 2017

Background: Despite substantial treatment advances and public health investment, out-of-hospital cardiac arrest (OHCA) remains a prominent medical concern worldwide. No recent population-based studies have examined the burden of OHCA across Canada. The objective of this study was to evaluate geographical differences in the incidence and outcomes of OHCA patients who were admitted to hospitals across Canada from 2013 to 2017.

METHODS AND RESULTS: This population-based retrospective cohort study included 10,492 non-traumatic OHCA patients aged 2-85 years who were admitted to an acute care hospital in any Canadian province or territory (excluding Quebec) between 2013 and 2017. Cardiac arrest diagnosis codes were used to identify OHCA-related admissions in the Canadian Institute for Health Information Discharge Abstract Database. The primary outcome was survival to hospital discharge. Overall age- and sex-standardized incidence measures (per 100,000 population per year) were calculated through direct standardization to the 2016 Canadian population. Temporal trends in incidence measures were evaluated using negative binomial regression, whereas temporal trends in outcomes were compared using the Cochrane-Armitage trend test. The median age of OHCA patients was 66 years, of which 66% were male. Hypertension (28%), diabetes (21%), heart failure (16%), and coronary artery disease (16%) were the most prevalent comorbidities in this cohort. The proportion of patients who underwent a cardiovascular procedure within 5 years before their index OHCA was 14%, whereas 42% were hospitalized for a cardiovascular-related condition within 5 years. The overall age- and sex-standardized incidence of OHCA patients admitted to the hospital in Canada (excluding Quebec) was 8.3 per 100,000 population per year, which did not significantly change from 2013 to 2017 (incidence rate ratio: 1.01, 95% confidence interval: 0.99-1.02). The age- and sex-standardized incidence was highest in British Columbia (9.2), Manitoba (9.0), and Nova Scotia (9.0), whereas lowest in New Brunswick (6.5), Prince Edward Island (6.8), and Saskatchewan (7.5). Over the 5-year period, the proportion of admitted OHCA patients who survived to hospital discharge was highest in Prince Edward Island (57%) and lowest in Ontario (38%), with a national average of 43%. No significant trend in survival to hospital discharge was observed from 2013 (43%) to 2017 (42%; p=0.86).

Conclusion: The age- and sex-standardized incidence of OHCA patients admitted to the hospital was stable from 2013 to 2017, with no significant change in the proportion of patients who survived to hospital discharge. Considerable variation in the incidence and outcomes of OHCA patients admitted to the hospital was observed across Canada.