Outcomes of percutaneous coronary intervention in Indigenous Australians in Victoria: a gap worth closing.

Abstract

Background: Indigenous Australians have disproportionately high rates of cardiovascular disease and mortality. There are limited data assessing outcomes following percutaneous coronary intervention (PCI). Methods: We included 179 patients identifying as Indigenous Australian from the Melbourne Interventional Group PCI registry (2005-2018) with comparison to the remaining cohort (N=39,855). Multivariable analysis was performed with adjustment for age, sex, comorbidities, and clinical status at presentation. Results: Indigenous patients were younger and more often female, with higher rates of regional or rural residence, current smoking, diabetes, severe renal impairment, dialysis, previous coronary disease, acute coronary syndromes, and impaired left ventricular function, all p<0.01. Door-to-balloon time was longer for STEMI patients (median 102 mins vs 77 mins, p=0.03) and length-of-stay longer (median 4 days vs 3 days, p<0.01). Stent selection, access choice, adjuvant treatments, procedural success and medications at 30-days were similar, but fewer patients could be contacted by the registry for 30-day medication follow-up (80% vs 92%, p<0.05) – suggestive of possible loss to medical follow-up. In multivariable analysis, Indigenous Australian status was associated with increased risk of long-term mortality (mean follow-up 5.7 years), 30-day MACE, and in-hospital bleeding. Risk of 30-day mortality was higher after adjustment for age, sex and comorbidities (but not clinical status). Conclusions: Indigenous Australians are at higher risk of adverse outcome following PCI. There were no observed biases for in-hospital care provision. Improving PCI outcomes should be a focus for health policy, and programs targeting close clinical engagement and follow-up may be of great value.