The high rates of comorbidities in Indigenous Australians is responsible for an excess of major adverse cardiac and cerebrovascular events (MACCE) following CABG compared to non-Indigenous Australians.
However Indigenous Australian status alone is not a significant predictor of MACCE.
A retrospective cohort study from Townsville Hospital in north Queensland comprised 350 consecutive CABG patients of which 20.9% identified as Aboriginal or Torres Strait Islander.
Indigenous patients were younger, more likely to be female and had higher rates of smoking, diabetes, dyslipidaemia and renal impairment than other patients.
Despite being younger, Indigenous patients had similar rates of perioperative and mid-term mortality as non-Indigenous patients.
However Indigenous patients were more likely to experience MACCE at almost twice the rate of non-Indigenous patients (36.7% v 18.6%).
Rates of stroke (7.1% v 2.1%) and MI (17.5% v 8.0%) were more than double in the Indigenous patients.
“Following adjustment for preoperative and operative variables, Indigenous Australian status itself was not significantly associated with MACCE (AOR 1.578 (0.637–3.910) p = 0.324),” the study said.
“Independent associations with MACCE from the adjusted model were renal impairment (p = 0.047) and moderate-severe left ventricular impairment (p = < 0.001).”
The researchers noted that over-representation of Indigenous patients in the cohort (20.9% versus 10.4% of the catchment population) and mean age of death (56.8 v 69.7 years) demonstrated the significant burden of ischaemic heart disease in Indigenous Australians.
“From a cardiac surgical perspective, given comparable perioperative outcomes, the focus of cardiac surgical research on Indigenous Australian patients undergoing CABG should potentially be directed toward the postoperative period and whether a form of enhanced clinical follow-up may produce benefits in regards to reducing the excess of longer term MACCE and mortality in the Indigenous Australian CABG population.”
“Whether enhanced multidisciplinary follow-up after discharge involving regular input from relevant specialities including cardiology, endocrinology and nephrology would have benefits on reducing adverse outcomes following CABG in Indigenous Australian patients would be a particular area of interest.”
Ongoing efforts to reduce the impact of diabetes, renal impairment and heart failure in Indigenous Australians were also required.
An Editorial in Heart, Lung & Circulation said several studies have now demonstrated that the higher prevalence of comorbidities in Indigenous people drives poorer outcomes.
It said any successful strategies to address the disparities were likely to require:
- Indigenous community supportive
- Socioeconomic and cultural engagement
- Culturally appropriate health behaviour modification programs (such as smoking cessation, regular exercise and healthy diets)
- Increased primary health awareness and targeted preventative care initiatives
- Aggressive and targeted secondary prevention strategies for renal disease and diabetes
- Indigenous targeted rehabilitation that is accessible in regional and remote areas.
“Indigenous cardiovascular health should not only be a federal and state government priority, but a cardiovascular academic and clinical priority as well.”
The CSANZ 3rd Indigenous Cardiovascular Health Conference is on in Wellington, New Zealand from 12-13 June.