1.05 Cardiovascular disease

Key messages

• In 2018–19, 16% of Aboriginal and Torres Strait Islander people reported living with cardiovascular disease in 2018–19 (ages 2 and over).
• In 2018–19, Indigenous Australians living in remote areas reported higher rates of cardiovascular disease (18%), compared with those in non-remote areas (15%).
• In the years 2015–2019 combined, cardiovascular disease was the second leading cause of death (3,471 deaths or 23% of total deaths) for Indigenous Australians, and the leading cause of the gap in death rates between Indigenous and non-Indigenous Australians.
• Between 2015–2019, the leading causes of death from cardiovascular disease for Indigenous Australians were coronary heart disease and cerebrovascular disease accounting for 56% and 15% of cardiovascular disease deaths respectively.
• After adjusting for differences in age, the hospitalisation rate for cardiovascular disease for Indigenous Australians was 1.6 times the rate for non‑Indigenous Australians from July 2017 to June 2019.
• Over the decade from 2010 to 2019, the death rate from cardiovascular disease for Indigenous Australians decreased by 18%, with no significant change in the gap between Indigenous and non-Indigenous Australians.
• Of Indigenous Australians who reported having cardiovascular disease in 2018–19, 56% reported also having diabetes and 72% reported also having kidney disease.
• In 2018–19, 75% of Indigenous adults whose blood pressure was measured as high during voluntary testing had not reported this to be the case when surveyed.
• Over the decade 2009–10 to 2018–19, age-standardised hospitalisation rates for cardiovascular disease for Indigenous Australians increased by 21%.
• After adjusting for differences in the age structure of the two populations, Indigenous Australians who were hospitalised for coronary heart disease were less likely to receive a coronary angiography (a diagnostic procedure) than non-Indigenous Australians (40% compared with 46%), and less likely to receive a revascularisation procedure (surgical procedure to restore blood supply to the heart) (19% compared with 24%)
• The culturally responsive Work It Out program, a 12-week chronic condition self-management program implemented by Aboriginal Community Controlled Health Services, demonstrated significant improvements in key clinical outcome measures such as blood pressure, weight and a six-minute walk test. Improvements were most evident in clinical outcome measures that were responsive to exercise and behavioural change.
• The Lighthouse Hospital Project has found that some key initiatives have led to improvements in care such as the expansion of the Aboriginal Health Workforce, better Indigenous status identification of patients, engaging in effective partnerships with Indigenous communities, fostering champions among clinical staff, patient-centred care and improved communication.

Why is it important?

Cardiovascular disease is a major cause of morbidity and mortality among Australians (see measure 1.23 Leading cause of mortality). Cardiovascular disease, also known as circulatory diseases, includes a range of conditions affecting the heart and blood vessels such as coronary (also known as ischaemic) heart disease, stroke and other cerebrovascular diseases

Cardiovascular disease is more common among Aboriginal and Torres Strait Islander people than non-Indigenous Australians and its onset tends to occur between 10 and 20 years younger than among non-Indigenous Australians (AIHW 2015; Bradshaw et al. 2011; Brown 2012; Brown & Kritharides 2017; Katzenellenbogen et al. 2014). Based on reported data from the 2018–19 National Aboriginal and Torres Strait Islander Health Survey (NATSIHS), Indigenous Australians aged 2–14 were twice as likely as non-Indigenous Australians of the same age to have a heart or cardiovascular disease.

Risk factors such as physical inactivity, obesity, diabetes, high blood pressure and tobacco smoking are more prevalent among Indigenous Australians than non-Indigenous Australians (Gray et al. 2012). Tobacco smoking levels are high among Indigenous adults, although rates have declined in recent years (see measure 2.15 Tobacco use). Acute rheumatic fever and rheumatic heart disease are preventable diseases affecting disadvantaged populations. There are high rates of these diseases among Indigenous Australians, particularly among young people (see measure 1.06 Acute rheumatic fever and rheumatic heart disease). Low socioeconomic status is associated both with greater risk of developing cardiovascular disease and with lower chance of receiving appropriate treatment (Beard et al. 2008; Cunningham 2010).

Burden of disease

In 2018, cardiovascular disease was the third leading cause of total disease burden (DALY) among Indigenous Australians, accounting for 10% (24,612 DALY) of the total disease burden, 19% of fatal burden (premature death (21,266 YLL)) and 2.6% of non-fatal burden (living with illness or disability (3,346 YLD)). Most of the burden due to cardiovascular disease was fatal (86%), with 14% being non-fatal.

Coronary heart disease and stroke were the main causes of the total cardiovascular disease burden (57% and 13%, respectively). This varied by age group. Among children under 5 years, inflammatory heart disease was the leading cause of cardiovascular disease burden (40% of cardiovascular disease burden). For ages 5–14, rheumatic heart disease and non-rheumatic valvular disease were the leading causes of burden (46% and 21%, respectively). For those aged 15–24, rheumatic heart disease was the leading cause of burden (25%), while coronary heart disease accounted for over half the cardiovascular disease burden in those aged 25 and over.

The age-standardised rate of cardiovascular disease burden for Indigenous Australians was 2.4 times the rate for non-Indigenous Australians and was the second leading cause of the gap in disease burden between Indigenous and non-Indigenous Australians (14% of the total gap) (AIHW 2022c).

Deaths from cardiovascular diseases

Deaths data in this measure are from five jurisdictions for which the quality of Indigenous identification in the deaths data is considered to be adequate: namely, New South Wales, Queensland, Western Australia, South Australia and the Northern Territory. Data by remoteness are reported for all Australian states and territories combined (see Data sources: National Mortality Database).

In the 5-year period 2015–2019, among Indigenous Australians:

• Cardiovascular disease was the second leading cause of death accounting for 3,471 deaths (23% of total deaths) (Table D1.23.1). Of these, 56% were deaths of Indigenous males.
• The rate of deaths due to cardiovascular disease among Indigenous Australians was 97 deaths per 100,000 population, with a higher rate for males than females (109 compared with 84 per 100,000, respectively).
• The leading causes of death from cardiovascular disease were coronary heart disease, with 1,932 deaths (56%), and cerebrovascular disease, with 527 deaths (15%) (Table D1.23.8).
• 12.6% of the 3,471 deaths from cardiovascular disease were caused by stroke. The death rate due to stroke for Indigenous Australians was 12.2 per 100,000.

Between 2015–2019, the death rate due to cardiovascular disease among Indigenous Australians was lowest in New South Wales (74 per 100,000) and highest in the Northern Territory (154 per 100,000) (Table D1.23.2). Across Australia, the rate was lower in non-remote areas (Major cities, Inner regional and Outer regional areas combined) (78 per 100,000) than in remote areas (Remote and Very remote areas combined) (152 per 100,000) (Table D1.23.30).

After adjusting for differences in the age structure between the two populations, the cardiovascular disease death rate for Indigenous Australians was 1.5 times the rate for non-Indigenous Australians (Table D1.23.1). The gap was higher in remote areas, where the rate of death due to cardiovascular disease among Indigenous Australians was 2.3 times the rate for non-Indigenous Australians (Table D1.23.30).

Cardiovascular diseases were the leading cause of the gap in death rates between Indigenous and non-Indigenous Australians in 2015–2019 (21% of the total gap in age-standardised death rates) (Table D1.23.1). Coronary heart disease was the largest contributor to the gap in cardiovascular disease deaths (68% of gap) (Table D1.23.8).

Hospitalisation due to cardiovascular disease

From July 2017 to June 2019, there were 31,051 hospitalisations for Indigenous Australians with a principal diagnosis of cardiovascular disease. It contributed to 2.9% of all hospitalisations of Indigenous Australians (including dialysis) (Table D1.02.5).

The  hospitalisation rate due to cardiovascular disease among Indigenous Australians was 19 hospitalisations per 1,000 population, with similar rates for Indigenous males (19 per 1,000) and Indigenous females (18 per 1,000) (Table D1.05.6).

Hospitalisation rates for cardiovascular disease increased with age and were highest among Indigenous Australians aged 65 and over (110 per 1,000) (Figure 1.05.1).

Figure 1.05.1: Hospitalisation rates for cardiovascular disease (based on principal diagnosis), by Indigenous status and age, Australia, July 2017 to June 2019

Source: Table D1.05.6. AIHW analysis of National Hospital Morbidity Database.

By remoteness, the hospitalisation rate for cardiovascular disease for Indigenous Australians was higher in remote areas than non-remote areas, ranging from 14 to 21 per 1,000 across non-remote areas (Major cities, Inner regional, and Outer regional areas), compared with 30 per 1,000 in Remote areas, and 28 per 1,000 in Very remote areas (Table D1.05.8).

Hospitalisation rates for cardiovascular disease for Indigenous Australians also varied by jurisdiction – the lowest was 9.6 per 1,000 in Tasmania, and the highest was 31 per 1,000 in the Northern Territory (Table D1.05.7).

After adjusting for differences in the age structure between the two populations, the hospitalisation rate for cardiovascular disease for Indigenous Australians was 1.6 times the rate for non‑Indigenous Australians (Table D1.05.7). The relative difference was higher in both Remote and Very remote areas, where the rate among Indigenous Australians was 2.2 times the rate for non-Indigenous Australians (Table D1.05.8).

The leading cause of hospitalisation for cardiovascular disease among Indigenous Australians was coronary heart disease (10,594 hospitalisations, 6.4 per 1,000) (Table D1.05.9, Figure 1.05.2). Coronary heart disease is disease due to blockages in the heart’s own (coronary) arteries, expressed as angina or a heart attack.

Another leading cause was cerebrovascular disease (3,144 hospitalisations, or 1.9 per 1,000 population), which is any disorder of the blood vessels supplying the brain or its covering membranes. A major form of cerebrovascular disease is stroke.

In the period July 2017 to June 2019, there were 2,756 hospitalisations of Indigenous Australians with stroke as the principal diagnosis, 8.9% of all hospitalisations with a principal diagnosis of cardiovascular disease (31,051). The hospitalisation rate for stroke was 1.7 per 1,000 for Indigenous Australians. After adjusting for differences in the age structure of the two populations, Indigenous Australians were 1.4 times as likely to be hospitalised for stroke as non-Indigenous Australians (AIHW 2021a).

Figure 1.05.2: Hospitalisation rates for cardiovascular disease (based on principal diagnosis) among Indigenous Australians, by disease type, Australia, July 2017 to June 2019

Source: Table D1.05.9. AIHW analysis of National Hospital Morbidity Database.

After adjusting for differences in the age structure of the two populations, Indigenous Australians who were hospitalised for coronary heart disease were less likely (a ratio of 0.9) to receive a coronary angiography (a diagnostic procedure) than non-Indigenous Australians (40% compared with 46%, based on age-standardised rates), and less likely (a ratio of 0.8) to receive a revascularisation procedure (surgical procedure to restore blood supply to the heart) (19% compared with 24%) (see also measure 3.06 Access to hospital procedures) (Table D3.06.9).

The age-standardised proportion of Indigenous adults hospitalised for a heart attack who received an angiography or revascularisation procedure increased from 35% in 2006–07 to 66% in 2018–19. This is lower than the proportion for non-Indigenous adults in 2018–19 (71%). This was for New South Wales, Victoria, Queensland, Western Australia, South Australia and the Northern Territory combined (AIHW 2021a).

Primary health care data

There is limited information available about Indigenous patients visiting mainstream general practice.

Based on the Bettering the Evaluation and Care of Health (2010–15) survey, which has now ceased, 8% of the total problems managed by General Practitioners (GPs) for Indigenous Australians were for cardiovascular problems. The most common cardiovascular problems managed for Indigenous Australians were related to high blood pressure (3.6%).

After adjusting for differences in the age structure between the two populations, GPs managed cardiovascular problems at a rate of 182 per 1,000 encounters for Indigenous Australians, compared with 168 per 1,000 for Other Australians. Problems relating to high blood pressure were managed at similar rates—83 per 1,000 GP encounters for Indigenous Australians and 85 per 1,000 GP encounters for Other Australians. However, rates were higher for Indigenous Australians than Other Australians for GPs managing problems relating to coronary (ischaemic) heart disease (1.5 times—17 and 11 per 1,000, respectively) and heart failure (1.7 times—11 and 6 per 1,000, respectively).

Indigenous Australians were less likely than Other Australians to attend a GP for a cardiac check-up (0.6 times—6 and 10 per 1,000, respectively), and saw a GP for atrial fibrillation/flutter (irregular or rapid heart rate) at similar rates to Other Australians (both 14 per 1,000) (Table D1.05.5).

MedicineInsight is another valuable data collection that provides longitudinal surveillance data of GP services and medicine prescriptions for Australians and Indigenous Australians. In 2020­–21, for every 100 GP clinical encounters with Indigenous patients, 3 had a record of cardiovascular diseases (including coronary artery disease, peripheral vascular disease, atrial fibrillation, heart failure, stroke and transient ischaemic attack). These encounters resulted in 41,722 issued prescriptions and 222,019 total prescriptions (issued and repeated prescription) of medicines for Indigenous patients with cardiovascular diseases. That contributed to 13% and 23% of all issued and total prescriptions for Indigenous patients, respectively (NPS MedicineWise 2022).

Information on cardiovascular risk assessments for Indigenous Australians attending Aboriginal and Torres Strait Islander specific primary health care organisations is available using data from the national Key Performance Indicators (nKPI). At June 2021, 59% of Indigenous regular clients aged 35–74 with no known history of cardiovascular disease who had an absolute cardiovascular disease risk recorded in the previous 24 months had a low absolute cardiovascular disease risk, 6% had moderate risk, and 34% had high risk (AIHW 2022a).

Findings from ABS survey data

Based on reported data from the 2018–19 Aboriginal and Torres Strait Islander Health Survey, 16% of Indigenous Australians aged 2 and over had cardiovascular disease (Table D1.05.2). Indigenous Australians were 1.5 times as likely as non-Indigenous Australians to report having cardiovascular disease, based on age-standardised rates (Table D1.05.2).

Looking at subcategories of cardiovascular disease, among Indigenous Australians in 2018–19, an estimated:

• 5.2% of Indigenous Australians had heart, stroke and vascular disease: this includes people who had ischaemic heart diseases (angina, heart attack and other ischaemic heart diseases), cerebrovascular diseases (stroke and other cerebrovascular diseases), oedema, heart failure, and diseases of the arteries, arterioles and capillaries.
• 8.3% had high blood pressure (hypertension) (see also measure 1.07 High blood pressure).
• 6.9% had other cardiovascular diseases: this includes any cardiovascular diseases not included in the categories above, such as tachycardia, low blood pressure, and cardiac murmurs (Table 1.05-1).

After adjusting for differences in the age structures of the two populations, Indigenous Australians were 2.1 times as likely to have heart, stroke and vascular disease as non-Indigenous Australians (8.5% compared with 4.1%) (ABS 2019).

Table 1.05-1: Proportion of people with cardiovascular disease, by Indigenous status, 2018–19

	Per cent (crude)	Age-standardised per cent
	Indigenous	Indigenous	Non-Indigenous
Heart, stroke and vascular disease	5.2	8.5	4.1
High blood pressure (hypertension)	8.3	13.4	9.3
Other cardiovascular diseases	6.9	9.6	5.3
Total cardiovascular diseases(a)	15.2	22.6	14.8

(a) Components do not sum to total and people may have more than one type of cardiovascular disease.

Note: Data are for people who had a current heart or circulatory (cardiovascular) condition which has lasted, or is likely to last, for 6 months or more (based on reported survey data). The ABS source publication uses the terminology ‘circulatory system’ diseases when describing these data – the AIHW has changed this to the synonymous term ‘cardiovascular diseases’ for consistency throughout measure.

Source: National Aboriginal and Torres Strait Islander Health Survey (ABS 2019)

In 2018-19, reported rates for cardiovascular disease increased with age, and were higher for Indigenous Australians than non-Indigenous Australians in every age group (from 2–14 to 55 and over) (Table D1.05.2, Figure 1.05.3).

Figure 1.05.3: Persons (aged 2 and over) reporting cardiovascular disease, by Indigenous status and age, 2018–19

Source: Table D1.05.2. AIHW and ABS analysis of National Aboriginal and Torres Strait Islander Health Survey 2018–19 and National Health Survey 2017–18.

Cardiovascular disease was more commonly reported by Indigenous females (17%) than Indigenous males (14%) (Table D1.05.1).

Indigenous Australians living in remote areas reported higher rates of cardiovascular disease (18%), compared with those in non-remote areas (15%) (Table D1.05.1). Across jurisdictions, the proportion of Indigenous Australians reporting cardiovascular disease ranged between 13% (in South Australia) and 18% (in the Northern Territory).

After adjusting for differences in age structure between the two populations, rates of cardiovascular disease were higher for Indigenous Australians than for non-Indigenous Australians in every jurisdiction, ranging between 1.2 times as high (in Victoria) to 2.3 times as high (in the Northern Territory) (Table D1.05.2, Figure 1.05.4).

Figure 1.05.4: Aged standardised rate of Australians aged 2 and over reporting cardiovascular disease, by Indigenous status and jurisdiction, 2018–19

Source: Table D1.05.2. AIHW and ABS analysis of National Aboriginal and Torres Strait Islander Health Survey 2018–19 and National Health Survey 2017–18.

In 2018–19, Indigenous Australians who were aged 15 and over and living in the most disadvantaged areas (1st quintile) were 3 times as likely to report having cardiovascular disease as those in the most advantaged areas (5th quintile) (23% compared with 8%) (classified using the Index of Relative Socio-Economic Advantage and Disadvantage 2016). Indigenous Australians were also more likely to report having cardiovascular disease if they completed schooling to Year 9 (33%) compared with those who completed Year 12 (17%) (Table D1.05.3).

In 2018–19, of Indigenous Australians reporting cardiovascular disease, 56% reported also having diabetes and 72% reported also having kidney disease (Table D1.05.3). Results from the 2018–19 NATSIHS showed that 75% of Indigenous adults whose blood pressure was measured as high had not reported this to be the case (see measure 1.07 High blood pressure) (Table D1.07.2).

The 2012–13 Australian Aboriginal and Torres Strait Islander Health Survey measured selected biomedical risk factors for Indigenous adults. Of the estimated 91,500 (25%) Indigenous adults who had measured abnormal cholesterol levels, 91% had self-reported that they did not have high cholesterol levels (ABS 2014).

Changes over time in deaths

Between 2006 and 2019, the rate of death due to cardiovascular disease for Indigenous Australians decreased by a third (33%), based on age-standardised rates (Figure 1.05.1). The rate for non-Indigenous Australians decreased by a similar proportion (36%) over this period, with no significant change in the gap between the two populations (Table D1.23.18).

Over the decade 2010 to 2019, the rate of death due to cardiovascular disease for Indigenous Australians decreased by 18%, with no significant change in the gap between Indigenous and non-Indigenous Australians. Over this period the relative difference in rates between Indigenous and non-Indigenous Australians (rate ratio) ranged between 1.4 and 1.7 (Figure 1.05.5, Table D1.23.18).

In New South Wales, Queensland and Western Australia, deaths due to cardiovascular disease among Indigenous Australians declined by 15%–30% between 2010 and 2019 (based on age-standardised rates), with no significant change in the Northern Territory or South Australia (Table D1.23.28).

Figure 1.05.5: Age-standardised death rates and changes in the gap due to cardiovascular disease, by Indigenous status, NSW, Qld, WA, SA and NT, 2006 to 2019

Note: Rate difference is the age-standardised rate (per 100,000) for Indigenous Australians minus the age-standardised rate (per 100,000) for non-Indigenous Australians. Rate ratio is the age-standardised rate for Indigenous Australians divided by the age-standardised rate for non-Indigenous Australians.

Source: Table D1.23.18. AIHW National Mortality Database.

Changes over time in hospitalisations

Hospitalisation rates for Indigenous Australians due to cardiovascular disease increased by 21% over the decade 2009–10 to 2018–19, based on age-standardised rates. For non-Indigenous Australians, the rate decreased by 4.8%. This was for the six jurisdictions with Indigenous identification data of adequate quality (New South Wales, Victoria, Queensland, Western Australia, South Australia and the Northern Territory).

Over this period the relative difference in rates between Indigenous and non-Indigenous Australians (rate ratio) ranged between 1.3 in 2009–10 to 1.7 in 2018–19 (Table D1.05.11, Figure 1.05.6).

Figure 1.05.6: Age-standardised hospitalisation rates and changes in the gap for a principal diagnosis of cardiovascular disease, by Indigenous status, NSW, Vic, Qld, WA, SA and NT, 2006–07 to 2018–19

Note: Rate difference is the age-standardised rate (per 1,000) for Indigenous Australians minus the age-standardised rate (per 1,000) for non-Indigenous Australians. Rate ratio is the age-standardised rate for Indigenous Australians divided by the age-standardised rate for non-Indigenous Australians.

Source: Table D1.05.11. AIHW analysis of National Hospital Morbidity Database.

An examination of evidence on differences in coronary (ischaemic) heart disease outcomes among Australians between Major cities, Regional and Remote areas of Australia found there was a consistently higher burden observed outside Major cities. However, within Indigenous Australian populations fewer differences by remoteness were observed and some coronary (ischaemic) heart disease outcomes were not associated with remoteness (Alston et al. 2017).

Studies in the Northern Territory showed survival for stroke has improved among both non-Indigenous and Indigenous Australians over time, from 1999–2011 by You and others (2015); and from 1992–2013 by Zhao and others (2015). However, the incidence rate did not change for Indigenous or non-Indigenous Australians in the Northern Territory from 1999–2011 (You et al. 2015; Zhao et al. 2015).

A study in the Northern Territory of avoidable mortality for Indigenous Australians between 1985 and 2004 found improvements in conditions amenable to medical care but marginal improvement for conditions responsive to preventative measures. The study noted the reduction of deaths from stroke was consistent with improved drug therapies and intensive care, dedicated stroke units and surgical procedures (Li et al. 2009).

Disparities in access to medical care

Aboriginal and Torres Strait Islander people do not always have the same level of access to health services as non-Indigenous Australians. Disparities in use of health services may indicate problems with access to health services due to affordability, cultural safety, distance travelled (especially in remote areas), and previous experiences of racism in health care environments for themselves, family or community members and fear of how they will be treated (AIHW 2022b).

The Lighthouse Hospital Project aims to address the disparities in cardiovascular care. Phase 1 of the project, which involved review of literature, and past and existing initiatives, identified key elements of initiatives that made a difference to acute coronary syndrome care. These included expansion of the Aboriginal Health Workforce, better Indigenous status identification of patients, engaging in effective partnerships with Indigenous communities, fostering champions among clinical staff, patient-centred care and improved communication (AHHA 2022). Phase 2 involved the development and piloting of a toolkit to assist hospitals in undertaking quality improvement activities identified in Phase 1. In the pilot hospitals, outcomes included improvements in relationships with Aboriginal and Torres Strait Islander patients and communities, better identification of Indigenous patients, improved recognition of the importance and value of Aboriginal Liaison Officers, improved confidence of hospital staff in delivering culturally appropriate care, greater commitment to follow-up after discharge, and reduction in discharge against medical advice (AHHA 2022). Phase 3 of the Lighthouse Hospital Project aimed to reduce the incidence and impact of Discharge Against Medical Advice (DAMA) for Aboriginal and Torres Strait Islander people who experience coronary conditions. Evaluation of Phase 3 showed that more than three-quarters of Aboriginal and Torres Strait Islander peoples with ACS surveyed in Lighthouse Hospitals rated their hospital experience as ‘very good’ or ‘good’, and hospitals also made progress in areas such staff capacity of provide culturally appropriate patient-centred care, and engagement and relationships with community organisations (Heart Foundation 2022).

Randall and others (2013) reported that over the period 2000 to 2008, Indigenous Australians in New South Wales had a 37% lower rate of revascularisation in the 30 days after admission with myocardial infarction compared with non-Indigenous Australians (Randall et al. 2013).

A study of data from hospitals participating in the National Stroke Audit of acute services in 2009 found that Indigenous patients with stroke received a reduced quality of care in hospitals and experienced worse outcomes than non-Indigenous patients (Kilkenny et al. 2013). Indigenous patients were less likely than non-Indigenous patients to be treated in a stroke unit and to receive timely allied health assessments (Kilkenny et al. 2013). The authors noted that further research to explain the differences was needed.

A study of patients presenting to a New South Wales rural referral hospital with ischaemic stroke found that investigation and post-discharge care of Indigenous patients was inferior to non-Indigenous patients (Tiedeman et al. 2019). Indigenous patients were less likely than non-Indigenous patients to have investigations completed, including carotid imaging, and to receive follow up after discharge. This study provides further evidence of the need for change within the health care system, with clinical assessments and service accessibility needing further attention to ensure that stroke intervention and prevention services are optimised for Indigenous Australians by taking account of cultural, social and environmental factors during treatment. This includes improving the cultural safety of hospitals and addressing institutional racism, improving communication between non-Indigenous health professionals and Indigenous clients, and harnessing flexible and innovative approaches to follow-up care such as community based rehabilitation and tele-health rehabilitation (Blacker & Armstrong 2019; Tiedeman et al. 2019).

Barriers to medical care for Indigenous Australians

Qualitative evidence on the experience of Indigenous patients in Alice Springs identified barriers to care across the care continuum. Brown (2010) concluded that improvements to the delivery of treatments known to be effective would make a significant impact on adverse outcomes.

The Randall and others (2013) revascularisation study found that the disparity in the revascularisation rate was largely due to the hospital of first admission (there were lower revascularisation rates for all patients admitted to smaller regional and remote hospitals) and a higher comorbidity burden for Indigenous patients. Another study found patients with acute myocardial infarction admitted to smaller and more remote hospitals without onsite angiography had increased risk of short-term and long-term mortality (Randall et al. 2012). Barriers to specialist care in Regional and Remote areas need to be better understood and overcome (Brown & Kritharides 2017). Other research also indicates that, after adjusting for other factors, the strongest positive association with coronary angiography rates was admissions to private hospitals (Chew et al. 2016; Hua et al. 2017). These studies reflect the inequitable access to specialist care faced by Indigenous Australians where specialist care may be inaccessible or unaffordable.

A study in Western Australia also found gaps in access to cardiac rehabilitation and secondary prevention services for Indigenous Australians (Hamilton et al. 2016). Referral and attendance at cardiac rehabilitation services varied greatly across Western Australia, with lack of referral and enrolment related to a drive time of over 60 minutes to services. Alternative methods of delivery such as home-based cardiac rehabilitation via telehealth or mobile health platforms may overcome geographical isolation.

Assessment of cardiovascular risk

A number of scoring systems have been developed to estimate risk of cardiovascular diseases that contribute to preventive therapies. One of the most commonly used approaches is the Framingham risk model which has an important utility in prevention and early detection of cardiovascular diseases among the non-Indigenous population (Rémond et al. 2017). Framingham risk models (which account for risk factors associated with age, sex, cholesterol level, blood pressure, the presence of diabetes, and smoking) are widely used and advocated in guidelines for predicting 10-year risk of developing cardiovascular disease, but there is mounting evidence that local tailoring is often needed to make accurate predictions (Damen et al. 2019). In Australia, clinical guidelines recommend using the 1991 Framingham model developed in the United States, and an updated sex-specific model has been published. However, research findings suggest the updated model remains ineffective in predicting risks of cardiovascular disease for the Indigenous population. A study conducted in remote Indigenous communities in Far North Queensland suggested that the 1991 and 2008 Framingham models for assessing cardiovascular risk underestimated the risk by about one-third (Hua et al. 2017).

Noting that the existing cardiovascular health assessment tools and guidelines may not apply to all Indigenous Australians, Agostino and colleagues (2020) proposed new guideline recommendations tailored for Indigenous Australians. That includes lowering the recommended screening age to 18 years old to improve detection and early management of risk in Indigenous adults. In the context of persisting socioeconomic disadvantage and poor emotional wellbeing that has contributed to the gap in cardiovascular health between Indigenous and non-Indigenous Australians, it was recommended to look beyond the traditional biological markers when assessing risk of cardiovascular diseases in the Indigenous population (Agostino et al. 2020).

Primary and secondary prevention

There is evidence the Aboriginal Community Controlled Health Services (ACCHS) primary health-care model has contributed to improved cardiovascular health outcomes for Indigenous Australians (Campbell et al. 2018). Analysis of cardiovascular morbidity and mortality from 1995 to 2004 in a Northern Territory community where the sole provider of health care is an ACCHS found that, compared with all Indigenous Australians in the Northern Territory, the community had lower mortality from all causes and from cardiovascular disease and lower rates of hospitalisation with cardiovascular disease as a primary cause. There was also a lower prevalence of diabetes, hypertension, obesity and smoking in the community. Rowley et al. (2008) concluded that a likely contributor was the nature of the primary health-care services provided by the ACCHS, including regular outreach to outstation communities (Rowley et al. 2008).

A cardiovascular and pulmonary rehabilitation program designed and provided by an ACCHS in Tasmania to Indigenous Australians with diagnosed chronic heart or respiratory disease or at high risk of developing such conditions was evaluated for the period October 2011 to July 2013 (Davey et al. 2014). The evaluation found that the program increased participation in rehabilitation and led to positive changes in health behaviours, exercise capacity and health related quality of life.

Other examples of cardiovascular programs successfully run and monitored by ACCHSs include the TORPEDO study, a randomised controlled trial of the use of an electronic decision-support system measuring absolute cardiovascular risk. The study randomised 60 Australian primary health-care services recruited between September 2011 and May 2012 and found that ACCHSs outperforming general practices in managing risk (Peiris et al. 2015). Patients with high cardiovascular risk were more likely to be prescribed recommended medications based on the management guidelines for cardiovascular diseases at ACCHSs compared with those attending general practices.

The Work It Out program, a chronic condition self-management group program, was evaluated for its effect on clinical outcome measures in urban Indigenous Australian adult participants with, or at risk of, cardiovascular disease (Mills et al. 2017).The program ran over 12 weeks, and clients could participate in two or more Work It Out sessions a week, with flexibility for participants to miss sessions due to family and community responsibilities and return to the program at a later date. A Work It Out session consisted of a yarning education session delivered in a culturally safe environment by a health professional, followed by an individually tailored exercise program undertaken in a group setting. There were 85 eligible participants, recruited from a population with or at risk of chronic disease who attended one of six participating ACCHS in Southeast Queensland between 2012 and 2014. This evaluation found that several measures improved over the short-term, these being increased distance travelled in the six-minute walk test; a reduction in weight for participants with extreme obesity; and decreases in systolic blood pressure. These improvements occurred in measures that were more responsive to exercise and behaviour change within shorter time periods, and could be indicative of improvement in other clinical outcome measures over the longer term. The evaluation also noted increased benefits in particular for participants experiencing numerous social and emotional wellbeing conditions, which requires further investigation (Mills et al. 2017).

In recent decades, Indigenous death rates from cardiovascular disease have fallen, due to reduced smoking; improved management of high blood pressure and heart disease; and improved treatments for heart attack and stroke. However, cardiovascular disease remains one of the leading causes of death for Indigenous Australians and high rates of obesity, diabetes and chronic kidney disease threaten to slow or reverse these improvements.

The National Strategic Action Plan for Heart Disease and Stroke  (the Action Plan) recognises that early detection and ongoing management of those at high risk of heart disease and stroke can save lives and reduce avoidable hospital admissions. There are two areas that will deliver significant gains in addressing the burden of heart disease and stroke in Australia: primary prevention for using population health measures to promote good health and individualised management and treatment for those at high risk, and secondary prevention for better management of people who have had a heart attack or stroke or are living with heart disease (who are at much higher risk of further events or hospitalisation) (Department of Health and Aged Care 2021).

The Action Plan includes Aboriginal and Torres Strait Islander peoples as a priority group facing disadvantages that significantly increase their likelihood of being affected by heart disease and stroke. The Action Plan provides a roadmap to achieve a healthier Australia through effective prevention, treatment and management of heart disease and stroke (Department of Health and Aged Care 2021). The four Priority Areas linking to the Action Plan’s objectives are:

1. Prevention and Early Detection: focus on primary and secondary prevention and early detection of heart disease and stroke for a healthier Australia.
2. Diagnosis and Treatment: provide efficient, effective, and appropriate access to diagnosis and treatment for heart disease and stroke for all Australians.
3. Support and Care: provide access to support mechanisms for patients, carers and health professionals to provide and receive the best support and care for heart disease and stroke.
4. Research: ensure a well-funded, collaborative approach to heart (disease) and stroke research and its translation into practice.

Cardiovascular disease occurs among Indigenous Australians from a younger age, between 10 and 20 years younger than among Other Australians (Brown & Kritharides 2017). A number of organisations, including the Royal Australian College of General Practitioners and National Aboriginal Community Controlled Health Organisation, have issued a joint recommendation that Indigenous adults should undergo cardiovascular risk factor screening from age 18 at the latest (Agostino et al. 2020). A study conducted between 2010 and 2012 in Australian primary health-care centres showed the importance of raising awareness and assessment of cardiovascular and diabetes risk in young Indigenous Australians and implementing preventative health-care strategies (Crinall et al. 2017). This study showed that while risk factors were being assessed, follow-up of abnormal results was undertaken less thoroughly. There is an opportunity to engage with primary health-care centres to strengthen their capacity to provide preventative health care for young people at risk of cardiovascular disease. This may contribute to reducing the chronic disease burden experienced by Indigenous young people. Agostino et al. (2020) also recommend that assessment using the National Vascular Disease Prevention Alliance absolute cardiovascular disease risk assessment algorithm should commence from age 30 at the latest. The new Guideline for assessing and managing cardiovascular disease risk is being finalised following public consultation during 2022. This also highlights the important role the ACCHS primary health care model plays in delivering preventative care, managing cardiovascular risk and secondary prevention for Indigenous clients with a high risk of heart attack or stroke.

Hospitalisation rates for cardiovascular disease were higher among Indigenous Australians and the increase in rates over the last 14 years may indicate improved access to care (AIHW 2021b). However, despite these improvements Indigenous Australians were still less likely to receive coronary procedures when in hospital than non-Indigenous Australians. While this is partly due to factors like comorbidities and the treatments available at specific hospitals, the evidence strongly suggests there are systematic differences in treatment for patients identified as Indigenous, indicating changes are required across the health system to improve cultural safety and to make the health system more responsive to the needs of Indigenous Australians, as well as making specialist care more accessible and affordable, particularly in regional and remote areas.

The National Aboriginal and Torres Strait Islander Health Plan 2021-2031 (the Health Plan), released in December 2021, includes a long-term vision to eliminate racism, with immediate action to address racism across the health system. An improved health system that is culturally safe and responsive to the needs of Indigenous Australians aligns to Priority Reform 3 of the National Agreement on Closing the Gap which aims to transform government organisations to work better for Indigenous Australians. The Health Plan also recognises early access to responsive primary care is also key to addressing the higher hospitalisation rates of Indigenous Australians, where presentation often occurs at a later stage of disease and can lead to higher rates of death. The Health Plan emphasises that action to address cardiovascular disease, diabetes, ear, eye and renal health, and rheumatic heart disease remain key priorities.

A significant body of work over the past two decades has sought to raise awareness and embed concepts of cultural respect in the Australian health system which are fundamental to improving access to quality and effective health care and improve health outcomes for Indigenous Australians. There has been a longstanding commitment by Australian governments to enable this. The Cultural Respect Framework 2016–2026 plays a key role in reaffirming this commitment and provides a nationally consistent approach (AHMAC 2016). The Aboriginal and Torres Strait Islander Health Performance Framework plays a role in monitoring this commitment across several measures (see measure 3.08 Cultural competency). Monitoring is also supported by the Cultural safety in health care for Indigenous Australians: monitoring framework which covers three domains: how health-care services are provided, Indigenous patients’ experience of health care, and measures regarding access to health care (AIHW 2022b). The 2022 Cultural safety report showed that a commitment to achieving culturally safe health care by Indigenous-specific health care organisations was 95% in 2017-18, an increase from 86% in 2012-13, while noting the lack of data available for reporting on the policies and practices of mainstream health services (AIHW 2022b). This lack of data presents a challenge to ensuring the availability of culturally safe and effective health services for Indigenous Australians. Walsh and others (2017) note that a better understanding of the factors contributing to the high burden of cardiovascular disease experienced by Indigenous Australians and potential mitigation strategies can assist clinicians in providing care to Indigenous Australians (Walsh & Kangaharan 2017). This includes understanding of cardiovascular disease presentations, realistic and patient-centric management approaches, and support mechanisms applicable to Indigenous communities.

The Lighthouse Hospital Project is funded through the Indigenous Australians’ Health Programme and is a joint initiative of the Heart Foundation and the Australian Healthcare and Hospitals Association (AHHA). The project aims to drive systemic change in the acute care sector to change the way hospitals and health services are governed, organised, structured and staffed to address institutional racism and improve care and outcomes for Indigenous Australians who experience acute coronary syndrome (ACS) (Heart Foundation 2022). It is designed to improve governance, clinical quality, and cultural competence of the health workforce. Each hospital in the program receives the Lighthouse Toolkit, which includes a plan, action areas, quality improvements, and outlines ways hospitals can provide culturally appropriate and clinically competent care for Indigenous Australians and their families. In 2017 phase three expanded the project to 18 hospitals across Australia. The evaluation of phase three of the project highlighted that more than three-quarters of Indigenous Australians with ACS surveyed in Lighthouse Hospitals rated their hospital experience as ‘very good’ or ‘good’.

The National Recommendations from the May 2014 Better Cardiac Care initiatives for Aboriginal and Torres Strait Islander People focus on five priority areas for action by all jurisdictions, including: early cardiovascular risk assessment and management; timely diagnosis of heart disease and heart failure; guideline-based therapy for acute coronary syndrome; optimisation of health status and provision of ongoing preventive care; and strengthening the diagnosis, notification and follow-up of rheumatic heart disease. The fifth national report on Better Cardiac Care measures for Aboriginal and Torres Strait Islander people 2020 shows progress against 7 of the 15 recommended measures, for which updated data were available. There has been significant improvement in three priority areas including Priority area 1: Early cardiovascular risk assessment and management; Priority area 2: Timely diagnosis of heart disease and heart failure; and Priority area 3: Guideline-based therapy for acute coronary syndrome. The level of access for cardiac-related health services has improved. The proportion of Indigenous Australians who received Medical Benefits Schedule (MBS) health assessments, cardiac-related diagnostic MBS services and the recommended intervention following hospitalisation for a severe heart attack has been increasing over time. However, there are still challenges in some areas, for example, although the death rate due to cardiac conditions for Indigenous Australians has improved significantly, the Indigenous death rate was 1.5 times the rate of non-Indigenous Australians between 2015 and 2019. Indigenous Australians with suspected or confirmed cardiac disease are less likely to be reviewed by a specialist than non-Indigenous Australians, are less likely than non-Indigenous Australians to receive the recommended intervention following hospitalisation for a severe heart attack, and experience much higher incidence and recurrence of acute rheumatic fever than among non-Indigenous Australians (AIHW 2021c).

The Health Plan is the overarching policy framework to drive progress against the Closing the Gap health targets and priority reforms. The Health Plan was developed in genuine partnership with Aboriginal and Torres Strait Islander leaders. Implementation of the Health Plan aims to drive structural reform towards models of care that are prevention and early intervention focused, with greater integration of care systems and pathways across primary, secondary and tertiary care. It also emphasises the need for mainstream services to address racism and provide culturally safe and responsive care, and be accountable to Indigenous Australians and communities.

The Health Plan suggests that efforts should be targeted at providing strengths based, culturally safe and holistic, affordable services to ensure early intervention across the life course. Vital to manage the development or progression of health conditions over time, early intervention must focus on the conditions with the potential to become serious, but that are preventable and/or easily treatable. Early intervention priorities may differ between communities depending on their location. For example, some Aboriginal and Torres Strait Islander communities are more strongly impacted by heart, ear or eye conditions. Therefore, place-based approaches must be locally determined and embed multidisciplinary care and partnerships. They must include pathways through primary health care (including identification of symptoms, diagnosis, treatment and follow-up care) to allied, specialist and tertiary care.

The Health Plan is aligned with the National Aboriginal and Torres Strait Islander Health Workforce Strategic Framework and Implementation Plan 2021–2031 (the National Workforce Plan), which aims to increase representation of First Nations peoples in all health roles and locations across Australia. It sets an ambitious target: for Indigenous Australians to represent 3.43% of the national health workforce by 2031. The National Workforce Plan commits governments to work in partnership with Indigenous Australians to meet this target and to foster a culturally safe and responsive health system.

As part of the National Agreement, the health sector was identified as one of four initial sectors for joint national strengthening effort and the development of a three-year Sector Strengthening Plan. The Health Sector Strengthening Plan (Health-SSP) was developed in 2021, to acknowledge and respond to the scope of key challenges for the sector, providing 17 transformative sector strengthening actions. Developed in partnership with the Aboriginal and Torres Strait Islander community-controlled health sector and other Aboriginal and Torres Strait Islander health organisations, the Health-SSP will be used to prioritise, partner and negotiate beneficial sector-strengthening strategies.

The Policy context is at Policies and strategies.

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