Long term outcomes for Aboriginal and Torres Strait Islander Australians after hospital intensive care

Objectives To assess long term outcomes for Aboriginal and Torres Strait Islander (Indigenous) Australians admitted non-electively to intensive care units (ICUs). Design Data linkage cohort study; analysis ofICUpatient data (Australian and New Zealand Intensive Care Society Adult Patient Database), prospectively collected during 2007-2016. Setting All four university-affiliated level 3ICUs in South Australia. Main outcomes Mortality (in-hospital, and 12 months and 8 years after admission toICU), by Indigenous status. Results 2035 of 39 784 non-elective indexICUadmissions (5.1%) were of Indigenous Australians, including 1461 of 37 661 patients with South Australian residential postcodes. The median age of Indigenous patients (45 years;IQR, 34-57 years) was lower than for non-IndigenousICUpatients (64 years;IQR, 47-76 years). For patients with South Australian postcodes, unadjusted mortality at discharge and 12 months and 8 years after admission was lower for Indigenous patients; after adjusting for age, sex, diabetes, severity of illness, and diagnostic group, mortality was similar for both groups at discharge (adjusted odds ratio [aOR], 0.95; 95%CI, 0.81-1.10), but greater for Indigenous patients at 12 months (aOR, 1.14; 95%CI, 1.03-1.26) and 8 years (adjusted hazard ratio, 1.23; 95%CI, 1.13-1.35). The number of potential years of life lost was greater for Indigenous patients (median, 24.0;IQR, 15.8-31.8v12.5;IQR, 0-22.3), but, referenced to respective population life expectancies, relative survival at 8 years was similar (proportions: Indigenous, 0.78; 95%CI, 0.75-0.80; non-Indigenous, 0.77; 95%CI, 0.76-0.78). Conclusions Adjusted long term mortality and median number of potential life years lost are higher for Indigenous than non-Indigenous patients after intensive care in hospital. These differences reflect underlying population survival patterns rather than the effects ofICUadmission.