Background
Methods
Search strategy
Eligibility criteria
Study selection
Data extraction
Risk of bias assessment of studies
Data analysis and synthesis
Confidence in cumulative evidence
Qualitative appraisal of literature – Indigenous perspective
Ethics approval and project oversight
Results
Study author and year of publication | Country (no. sites) | Study design | Data source & timeframe | Patients (n) | Population and comparison group | Patient characteristics | Outcome measures | Risk of bias (NOS)¶ | |
---|---|---|---|---|---|---|---|---|---|
Indigenous | Non-Indigenous | ||||||||
Davis JS et al. 2011 | Australia (1) | Prospective cohort | Hospital medical records/charts, pathology results May 2007-May 2008 | 1,090 | Adults > 15 years hospitalized with community-onset sepsis Indigenous vs. non-Indigenous | Age: 43.2 yr Male: 43.2% DM: 31.1% CKD: 18.9% CLD: 13.2% Sepsis: 100% APA II: N/A* SOFA: N/A** | Age: 50.2 yr Male: 61.8% DM: 16.5% CKD: 4.4% CLD: 5.3% Sepsis: 100% APA II: N/A* SOFA: N/A** | ICU admission | 5 |
Dunlop WA et al. 2020 | Australia (177) | Retrospective cohort | ANZICS Core national database Jan 1, 2010 – Dec 31, 2017 | 23,793 | Adults admitted to ICU with dialysis-dependent ESKD Indigenous vs. non-Indigenous | Age: 57.0 yr Male: 52.9% DM: 17.5% CKD: 100% CLD: 3.1% Sepsis: 19.0% ANZROD: 15 | Age: 70.5 yr Male: 62.0% DM: 17.3% CKD: 100% CLD: 2.8% Sepsis: 14.2% ANZROD: 16 | ICU LOS; ICU re-admission | 7 |
Flint SM et al. 2010 | Australia (1) | Prospective cohort | Hospital medical records; lab data June – August 2009 | 643 | Adults hospitalized with influenza-like illness Indigenous vs. non-Indigenous | Age: 39 yr Male: 47.0% DM: 24.0% CKD: 20.0% CLD: 11.0% > 1 comorbid: 74.0% APA II: N/Aα | Age: 46 yr Male: 64.0% DM: 21.0% CKD: 5.0% CLD: 5.0% > 1 comorbid: 72.0% APA II: N/Aα | ICU admission | 5 |
Hanson J et al. 2020 | Australia (1) | Retrospective cohort | Medical records; lab data Jan 1, 2014 – Jun 30, 2017 | 442 | Adults admitted to ICU with sepsis Indigenous vs. non-Indigenous | Age: 53 yr Male: 47.0% DM: 58.0% CKD: 39.0% CLD: 12.0% Sepsis: 100% APA II: 21.0 ANZROD: 24 | Age: 65 yr Male: 57.0% DM: 23.0% CKD: 10.0% CLD: 7.0% Sepsis: 100% APA II: 20.0 ANZROD: 23 | ICU mortality, IMV | 6 (ICU admission); 8 (ICU mortality) |
Ho KM et al. 2006 | Australia (1) | Retrospective cohort | ICU Audit database Jan 1, 1993 – Dec 31, 2003 | 16,757 | Adults admitted to ICU for elective surgery, emergency Indigenous vs. non-Indigenous | Age: 42.2 yr Male: 58.0% DM: N/A CKD: 7.0% CLD: 2.3% Sepsis: 14.5% APA II: 18.6 ANZROD: N/A | Age: 57.9 yr Male: 66.0% DM: N/A CKD: 1.0% CLD: 0.7% Sepsis: 4.0% APA II: 16.9 ANZROD: N/A | ICU mortality; ICU LOS | 6 |
Jung JJ et al. 2017 | Canada (51) | Prospective cohort | ICU-FLU electronic database Apr 16, 2009 – Apr 12, 2010 | 647 | Adults admitted to ICU for pH1N1 Indigenous vs. non-Indigenous | Age: 40.7 yr Male: 35.8% DM: 23.5% CKD: N/A CLD: N/A ≥ 1 comorbid: 92.6% APA II: 19.9 | Age: 49.0 yr Male: 49.9% DM: 26.9% CKD: N/A CLD: N/A ≥ 1 comorbid: 91.0% APA II: 21.1 | ICU LOS; IMV | 7 |
Keenan NM et al. 2019 | Australia (1) | Retrospective cohort | Flinders Cardiac Surgery Research database Feb 1, 1992 – Jul 31, 2017 | 236 | Adult undergoing redo heart valve surgery Indigenous vs. non-Indigenous | Age: 29.5 yr Male: 41.0% DM: 17.0% CKD: 18.0% CLD: N/A EuroSCORE II: 3.7 | Age: 67.0 yr Male: 68.0% DM: 19.0% CKD: 12.0% CLD: N/A EuroSCORE II: 4.3 | ICU LOS | 7 |
Khan NA et al. 2008 | Canada (3) | Retrospective cohort | ICU database registry Jan 1999 – Jan 2006 | 7,331 | Adults admitted to ICU Indigenous vs. European vs. Asian | Age: 48.4 yr Male: 48.0% DM: 19.0% CKD: N/A CLD: N/A IVDU: 30.0% Sepsis: 22.0% APA II: 21.6 | Age: 59.2 yr Male: 64.0% DM: 17.0% CKD: N/A CLD: N/A IVDU: 8.0% Sepsis: 12.0% APA II: 20.4 | ICU mortality; ICU LOS | 6 |
Laupland KB et al. 2006 | Canada (4) | Retrospective cohort | ICU Tracer database May 1, 1999 – Apr 30, 2002 | 6,272 | Adults admitted to ICU/CV ICU Indigenous (Status Aboriginal) vs. non-Indigenous (non-Status Aboriginal) | Age: 40.3 yr Male: 58.0% DM: N/A CKD: 5.0% CLD: N/A Sepsis: N/A APA II: 22.1 | Age: 65.3 yr Male: 63.0% DM: N/A CKD: 2.0% CLD: N/A Sepsis: N/A APA II: 24.9 | ICU mortality; ICU LOS; ICU admission; IMV | 8 (ICU admission); 9 (ICU mortality) |
Magee F et al. 2019 | Australia & New Zealand (92) | Retrospective cohort | ANZICS Adult patient database Jan 1, 2010 – Dec 31, 2015 | 23,804 | Adults > 17 years old admitted to ICU for trauma Indigenous vs. non-Indigenous | Age: 42.0 yr Male: 73.4% DM: 1.1% CKD: 1.7% CLD: 1.7% APA III: 27.0 ANZROD: 7.6 | Age: 48.3 yr Male: 74.0% DM: 1.2% CKD: 0.7% CLD: 0.9% APA III: 26.1 ANZROD: 8.8 | ICU LOS; ICU admission; IMV | 7 |
Maiden MJ et al. 2020γ | Australia & New Zealand (183) | Retrospective cohort | ANZICS Adult patient database Jan 1, 2008 – Dec 31, 2017 | 16,063 | Obstetric patients 15–49 years admitted to ICU Indigenous vs. non-Indigenous | Age: 31.3 yr DM: N/A CKD: N/A CLD: N/A Sepsis: 5.0% APA III: 32 ANZROD: 1.3 | ICU mortality; ICU LOS; IMV | 6 | |
Mitchell WG et al. 2020 | Australia (4) | Retrospective cohort | ANZICS Adult patient database Jan 1, 2007 – Dec 31, 2016 | 39,784 | Adults admitted non-electively to ICU Indigenous vs. non-Indigenous | Age: 45.0 yr Male: 54.0% DM: 32.0% CKD: 8.5% CLD: 6.2% Sepsis: 11.0% APA II: 17.0 ANZROD: N/A | Age: 64.0 yr Male: 58.0% DM: 20.0% CKD: 2.9% CLD: 2.6% Sepsis: 9.3% APA II: 18.0 ANZROD: N/A | ICU mortality; ICU LOS; IMV | 7 |
Reid Al et al. 2022 | New Zealand (17) | Retrospective cohort | New Zealand Ministry of Health National Minimum Dataset matched to ANZICS Adult patient database July 1, 2009 – June 30, 2018 | 52,552 | Adult patients ≥ 18 years old admitted to ICU Maori vs. European | Age: 53 yr Male: 55.6% DM: 30.2% CKD: 12.8% CLD: N/A Sepsis: 7.6% APA III: 50.6 ANZROD: 10.6 | Age: 66 yr Male: 62.7% DM: 17.7% CKD: 7.9% CLD: N/A Sepsis: 4.4% APA III: 46.0 ANZROD: 9.5 | ICU mortality; ICU LOS | 9 |
Secombe PJ et al. 2019 | Australia & New Zealand (148) | Retrospective cohort | ANZICS Adult patient database Jan 1, 2017 – Dec 31, 2018 | 246,718 | Adults admitted to ICU Indigenous vs. non-Indigenous | Age: 51.1 yr Male: 51.8% DM: N/A CKD: 9.4% CLD: 2.7% > 1 comorbid: 4.5% Sepsis: 14.9% APA III: 47.0 ANZROD: 8.6 | Age: 66.0 yr Male: 56.5% DM: N/A CKD: 3.0% CLD: 1.5% > 1 comorbid: 4.8% Sepsis: 9.1% APA III: 47.0 ANZROD: 8.1 | ICU mortality; ICU LOS; ICU re-admission; IMV | 7 |
Trout MI et al. 2015β | Australia (1) | Retrospective cohort | ANZICS Adult patient database Jan 1, 2007 – Dec 31, 2011 | 2,019 | Adults admitted to ICU ATSI vs. non-ATSI | Age: 53.0 yr Male: 56.0% DM: 7.4% CKD: 5.2% CLD: 1.4% Sepsis: 3.2% APA III: 38 ANZROD: N/A | Age: 63.0 yr Male: 72.2% DM: 3.6% CKD: 0.8% CLD: 0.3% Sepsis: 1.4% APA III: 42 ANZROD: N/A | ICU mortality; ICU LOS; IMV | 7 |
Primary outcome—ICU admission
Outcome | Comparator 1 vs. 2 | Study design (no. studies); Sample size | Absolute difference (95% CI) | Effect estimate (95% CI) | Certainty of evidence† | Conclusion | |
---|---|---|---|---|---|---|---|
Comparator 2 risk | Absolute risk difference | ||||||
ICU admission | Indigenous vs non-Indigenous | Prospective (2), Retrospective (2); Sample size range 161 to 18,742,918 people | NA | NA | ICU admissions among hospital admissions for severe sepsis: 4.7 per 1,000 (95% CI 3.8 to 5.7) vs. 0.9 per 1,000, p < 0.001; ICU admissions among patients hospitalized for H1N1: 35.3 per 100,000 (95% CI 16.5 to 54.4) vs. 5.7 per 100,000 (95% CI 1.8 to 9.9); age-adjusted incidence rate ratio: 5.2 (95% CI 2.3 to 12), p > 0.05; Annual incidence of ICU admissions among general population: 620.6 per 100,000 vs. 302.6 per 100,000; RR 2.1 (95% CI 1.78 to 2.35), p < 0.0001; ICU admissions with trauma-related injuries among general population: 847 per 1,000,000 vs. 251 per 1,000,000; incidence ratio 3.37 (95% CI 3.19 to 3.57), standardized to estimates for adult population of Australia | Low1,2 | Among general populations or hospitalized patients, there may be an increased risk in ICU admission for Indigenous compared with non-Indigenous populations |
ICU mortality | Indigenous vs non-Indigenous | Retrospective cohort (8); 368,541 people in ICU | 65 per 1,000 | 16 more per 1,000 (2 fewer to 40 more) | RR 1.14 (95% CI 0.98 to 1.34) | Low1,3 | Among people in ICU, there may be little-to-no difference in ICU mortality between Indigenous and non-Indigenous populations |