Differences in outcome of percutaneous coronary intervention between Indigenous and non-Indigenous people in Victoria, Australia: a multicentre, prospective, observational, cohort study

Abstract

Background Data on the patient characteristics and health outcomes of Indigenous Australians having revascularisation for treatment of coronary artery disease are scarce. The aim of this study was to assess differences in patient characteristics, presentations, and outcomes among Indigenous and non-Indigenous Australians having percutaneous coronary intervention (PCI) in urban and larger regional centres in Victoria, Australia.Methods In this multicentre, prospective, observational cohort study, data were prospectively collected from six government-funded tertiary hospitals in the state of Victoria, Australia. The Melbourne Interventional Group PCI registry was used to identify patients having PCI at Victorian metropolitan and large regional hospitals between Jan 1, 2005, and Dec 31, 2018. The primary outcome was long-term mortality. Secondary outcomes were 30 day mortality and 30 day major adverse cardiovascular events (MACE), defined as a composite endpoint of death, myocardial infarction, and target-vessel revascularisation. Regression analyses, adjusted for clinically relevant covariates and geographical and socioeconomic indices, were used to establish the influence of Indigenous status on these study outcomes.Findings 41 146 patient procedures were entered into the registry, of whom 179 (0•4%) were recorded as identifying as Indigenous Australian, 39 855 (96•9%) were not Indigenous Australian, and 1112 (2•7%) had incomplete data regarding ethnicity and were excluded. Compared with their non-Indigenous counterparts, Indigenous patients were younger, more often women, and more likely to have comorbidities. Indigenous Australians were also more likely to live in a regional community and areas of socioeconomic disadvantage. Procedural success and complication rates were similar for Indigenous and non-Indigenous patients having PCI. At 30 day follow-up, Indigenous Australians were more likely to be taking optimal medical therapy, although overall follow-up rates were lower and prevalence of persistent smoking was higher. Multivariable analysis showed that Indigenous status was independently associated with increased risk of long-term mortality (hazard ratio 2•49, 95% CI 1•79-3•48; p<0•0001), 30 day mortality (odds ratio 2•78, 95% CI 1•09-7•12; p=0•033), and 30-day MACE (odds ratio 1•87, 95% CI 1•03-3•39; p=0•039).Interpretation Indigenous Australians having PCI in urban and larger regional centres are at increased risk of mortality and adverse cardiac events. Clinically effective and culturally safe care pathways are urgently needed to improve health outcomes among Indigenous Australians who are having PCI.

Where are the opportunities to address system barriers preventing equitable cardiovascular outcomes for indigenous populations?

“…4 Evidence also exists of disparities in outcomes. 5 In The Lancet Global Health, Luke Dawson and coworkers 6 provide contemporary data on short-term, medium-term, and long-term outcomes following percutaneous coronary intervention (PCI) in Victoria, Australia. They report 2•5 times greater long-term mortality following PCI for Aboriginal and Torres Strait Islander people than in non-indigenous counterparts, and a similar disparity for 30 day mortality and major adverse cardiac events.…”

“…They report 2•5 times greater long-term mortality following PCI for Aboriginal and Torres Strait Islander people than in non-indigenous counterparts, and a similar disparity for 30 day mortality and major adverse cardiac events. 6 Of great concern in the Article's findings is the continued difference in long-term mortality over time, with virtually no change in the hazard ratio between the periods of 2005-09 and 2015-18. 6 This continued trend is despite in-hospital cardiac disparities for Aboriginal and Torres Strait Islander people being a national priority since 2014.…”

“…6 Of great concern in the Article's findings is the continued difference in long-term mortality over time, with virtually no change in the hazard ratio between the periods of 2005-09 and 2015-18. 6 This continued trend is despite in-hospital cardiac disparities for Aboriginal and Torres Strait Islander people being a national priority since 2014. 7 Targeted efforts over the past decade to increase culturally appropriate, clinically competent cardiac care in selected hospitals through addressing onthe-ground gaps seem not to have made any difference to disparities and outcomes more broadly.…”

“…Specifically for those with an acute episode of coronary heart disease, but also across the board for most health outcomes. 4 As stated by Dawson and coworkers, 6 there is a need to have a solutions-focused approach. It is not enough to continue to report the extent of the disparity.…”

“…Identification of indigenous clients within the system is far from accurate, resulting in missed opportunities to provide care that meets patient need. 6,10 The study provides a picture for six public hospitals in one jurisdiction, but we do not have broader understanding across jurisdictions, sectors, and remoteness. 6 Focus on the gap remains, but we need to focus on what is driving disparities so that evidencebased solutions are implemented.…”