Interprovincial Differences in Canadian Coronary Care Unit Resource Use and Outcomes.

International registries have reported a wide variation in coronary care unit (CCU) admission rates for patients hospitalized with acute coronary syndrome (ACS) or heart failure (HF). Little is known about variation in Canadian interprovincial use and outcomes. Canadian Institute of Health Information data were used to identify hospitalized patients admitted to a CCU with a primary diagnosis of ACS or HF between April 1, 2007 and March 31, 2013. We examined interprovincial differences in CCU admission rates, use of CCU restricted therapies in the first 2 days of admission, and the association between CCU admission rate and risk-adjusted in-hospital mortality at the provincial level. The CCU admission rate among 220,759 patients hospitalized with ACS and HF was 33%, and this varied significantly across provinces (interprovincial range [IPR] 17%-50%; P < 0.001). A majority (59%; IPR, 48%-84%; P < 0.001) of patients admitted to the CCU did not receive critical care restricted therapies within 2 days. In-hospital mortality also varied across provinces (10%; IPR, 5%-13%; P < 0.001). Although statistically significant (P < 0.001), the correlation between CCU admission rates and provincial risk-adjusted in-hospital mortality was low (r = -0.30). These findings highlight the need for national CCU admission criteria designed to reduce variability and improve health care resource use and outcomes.