Worse outcomes for Indigenous Australians with peripheral artery disease
In a first-of-its-kind study, James Cook University researchers have found Indigenous Australians with peripheral artery disease (PAD) are diagnosed at a younger age, have higher rates of smoking and insulin-treated diabetes, and poorer long-term outcomes compared to non-Indigenous Australians.
PAD refers to the narrowing of arteries responsible for circulation to the periphery of the body.
Dr Tejas Singh, a Junior Research Fellow at the JCU-based Queensland Research Centre for Peripheral Vascular Disease (QRCPVD) said the team looked at 401 PAD patients, of whom 16 were Indigenous Australians.
“It’s known that the risk factors for PAD are more common in Indigenous than non-Indigenous Australians, however the presenting characteristics and clinical outcome of PAD in Indigenous Australians has not been previously investigated,” he said.
Indigenous Australians with PAD were more commonly current smokers (56.3% vs 31.4%), and more frequently had insulin-treated diabetes (18.8% vs 5.2%) than the non-Indigenous patients. Indigenous PAD patients were significantly younger than non-Indigenous patients, suggesting an earlier onset of PAD in this population.
“In terms of outcomes, Indigenous Australians were at approximately 5-fold greater risk of having cardiovascular events in comparison to non-Indigenous Australians, after adjusting for relevant risk factors such as heart disease, high blood pressure, smoking and diabetes.”
Dr Singh said mortality attributed to PAD has previously been estimated to be higher in Australasia than in any other part of the world.
"One possible explanation for the high incidence and complication rates of PAD amongst the Australasian population is the greater incidence and poorer outcome of PAD in Indigenous Australians,” he said.
Dr Singh said the findings emphasised the need for more intensive management of modifiable risk factors in the Indigenous Australian population.
Link to paper here.
The prevalence of PAD is expected to double by 2040 due to an ageing population.
PAD patients are at approximately three times higher risk of cardiovascular and all-cause mortality, compared to those without PAD.
Indigenous Australians have previously been reported to have a 3-fold higher risk of developing PAD (adjusted for age, diabetes duration, and smoking status).
They also have more frequent risk factors for PAD compared to non-Indigenous Australians, including diabetes (5–10 fold higher), hypertension (3–8 fold higher), and smoking (5-fold higher).
Although smoking rates amongst non- Indigenous Australians has almost halved over the past 15 years, smoking rates have remained relatively unchanged in Indigenous Australians.
Indigenous Australians (Aboriginal and Torres Strait Islanders) have been previously reported to have a life expectancy of approximately 17 years less than non-Indigenous Australians, and a burden of disease 2.5 fold higher.
It has been estimated that the risk of major amputations (below or above the knee) in 25–49 year olds is approximately 40-fold higher in Indigenous populations compared to non- Indigenous Australians, attributable to the earlier onset of underlying conditions such as diabetes.