Distribution and determinants of critical illness among status Aboriginal Canadians. A population-based assessment

Abstract

Purpose The aim of the study is to determine the incidence, demographic risk factors, and outcomes of critical illness among all adult status Aboriginal Canadians (SACs) admitted to intensive care units (ICUs). Patients and Methods A population-based cohort was conducted among adult residents of the Calgary Health Region admitted to ICUs between May 1999 and April 2002. Patients were classified as SAC based on an alternate premium arrangement field within their Alberta personal health number. Results The annual incidence of critical illness among SACs of 620.6 per 100 000 was significantly higher than the non-SAC population of 302.6 per 100 000 (RR, 2.1; 95% CI, 1.78-2.35); this was due to a 3-fold higher admission rate to the multisystem ICUs among SAC (579.6 per 100 000/y) as compared with non-SAC patients (210.7 per 100 000/y; RR, 2.75; 95% confidence interval [CI], 2.37-3.17). The highest risk for ICU admission among SAC patients was observed in those aged 20 to 49 years, and the incidence was higher in males than females (772.3 vs 479.8 per 100 000/y; RR, 1.6; 95% CI, 1.21-2.14). Although the in-hospital case-fatality rate was only slightly higher among SAC (18%, 38/212) as compared with non-SAC patients (922/7159; 13%; RR, 1.39; 95% CI, 1.04-1.87), the annual mortality rate was much higher (146.4 per 100 000 for SAC vs 60.9 per 100 000 for non-SAC; RR, 2.40; 95% CI, 1.78-3.19). Conclusion This study demonstrates that SACs have an increased burden of critical illness as compared with the general non-SAC population and supports further research aimed at exploring means to reduce its adverse impact in this population.