HEART AND CIRCULATORY DISEASES

Heart, stroke and vascular disease encompasses a range of circulatory conditions including ischaemic heart diseases, cerebrovascular diseases, oedema, heart failure, and diseases of the arteries, arterioles and capillaries. Most commonly this group of conditions is referred to under the broader term of 'heart disease' (or 'cardiovascular disease'). According to the 2003 Australian Burden of Disease Study, high blood cholesterol, which is closely associated with ischaemic heart disease and stroke, accounted for 6% of the burden of disease in the Aboriginal and Torres Strait Islander population. Cardiovascular disease was the leading specific cause of death (Endnote 1).

Hypertensive heart disease includes heart failure, thickening of the heart muscle and coronary heart disease. All of these heart conditions are caused by high blood pressure, that is, the heart working under increased pressure. According to the 2003 Australian Burden of Disease Study, high blood pressure accounts for 5% of the total burden of disease, and 10% of deaths (primarily due to ischaemic heart disease and stroke) in the Aboriginal and Torres Strait Islander population (Endnote 1).

Data presented below on heart and circulatory diseases are for Aboriginal and Torres Strait Islander people who reported having been told by a doctor or nurse that they had any of a range of circulatory conditions including ischaemic heart diseases, cerebrovascular diseases, oedema, heart failure, and diseases of the arteries, arterioles and capillaries, and that the condition(s) were current.

More information on the number of Aboriginal and Torres Strait Islander people with heart disease, based on measured levels of blood lipids such as total cholesterol, will be available upon release of Australian Aboriginal and Torres Strait Islander Health Survey: Biomedical results later in 2014.

UPDATED RESULTS FROM 2012–13

In 2012–13, around one in eight (13%) Aboriginal and Torres Strait Islander people aged 2 years and over had heart and/or circulatory diseases.

A higher proportion of Aboriginal and Torres Strait Islander females than males had heart and/or circulatory diseases in 2012–13 (14% compared with 11%). Some of the difference may be explained by the larger proportion of women than men in older age groups, but it is likely that higher rates of obesity among females are also a contributing factor. The difference between overall age standardised rates for Aboriginal and Torres Strait Islander males and females was statistically significant.

Within the Aboriginal and Torres Strait Islander population, the proportion of people with heart and/or circulatory diseases increased in line with age, ranging from 2% of children aged 2–14 years to almost half (45%) of those aged 55 years and over.




In 2012–13, Aboriginal and Torres Strait Islander people in remote areas were significantly more likely than those in non-remote areas to have reported having heart and/or circulatory diseases (18% compared with 11%).

Heart, stroke and vascular disease

In 2012–13, one in twenty-five (4%) Aboriginal and Torres Strait Islander people aged 2 years and over had heart, stroke and/or vascular disease.

The prevalence of heart, stroke and vascular disease was the same for Aboriginal and Torres Strait Islander males and females (both 4%) and in non-remote and remote areas (both 4%).

Within the Aboriginal and Torres Strait Islander population, heart, stroke and vascular disease were prevalent from about 35 years of age onwards. One in twenty-five (4%) Aboriginal and Torres Strait Islander people aged 35–44 years reported heart, stroke or vascular disease, increasing to one in ten people aged 45–54 years (10%), and one in five (20%) of those aged 55 years and over.

Hypertensive disease (high blood pressure)

In 2012–13, around one in twenty (6%) Aboriginal and Torres Strait Islander people aged 2 years and over had hypertensive disease (high blood pressure).

The prevalence of hypertensive disease was the same for Aboriginal and Torres Strait Islander males and females (both 6%).

In 2012–13, Aboriginal and Torres Strait Islander people in remote areas were more than twice as likely as those in non-remote areas to have reported hypertensive disease (11% compared with 4%).

Within the Aboriginal and Torres Strait Islander population, hypertensive disease was prevalent from about 25 years of age onwards, with higher rates in older age groups. Around one in eight (12%) Aboriginal and Torres Strait Islander people aged 25 years and over had hypertensive disease, with rates ranging from 4% of Aboriginal and Torres Strait Islander people aged 25–34 years to 25% of those aged 55 years and over.


CHANGE OVER TIME

Between 2001 and 2012–13, there was a significant increase in the overall prevalence of heart and circulatory diseases among Aboriginal and Torres Strait Islander people aged 2 years and over (from 11% to 13%). While rates for heart and circulatory diseases rose in both non-remote and remote areas over the decade, only the increase in remote areas was statistically significant — from 13% to 18% over this period.

HOW DO THESE RATES COMPARE WITH THE RATES FOR NON-INDIGENOUS PEOPLE?

After adjusting for differences in the age structure of the two populations, Aboriginal and Torres Strait Islander people aged 2 years and over were significantly more likely than non-Indigenous people to have heart and/or circulatory diseases (rate ratio of 1.2). There were statistically significant differences in the age standardised rates for both females (rate ratio of 1.3) and males (rate ratio of 1.2).

The prevalence of heart and/or circulatory diseases among Aboriginal and Torres Strait Islander people was significantly higher than for non-Indigenous people in all age groups from 2–54 years.

Heart, stroke and vascular disease

After adjusting for differences in the age structure of the two populations, Aboriginal and Torres Strait Islander people were significantly more likely than non-Indigenous people to have reported heart, stroke or vascular disease (rate ratio of 1.6). There were statistically significant differences in the age standardised rates for both females (rate ratio of 1.7) and males (rate ratio of 1.5).

The prevalence of heart, stroke and vascular disease among Aboriginal and Torres Strait Islander people was significantly higher than for non-Indigenous people in all age groups from 35 years onwards.

Hypertensive disease (high blood pressure)

After adjusting for differences in age structure between the two populations, the prevalence of hypertensive heart disease in the Aboriginal and Torres Strait Islander and non-Indigenous populations was the same (rate ratio of 1.0). This was true for males (rate ratio of 1.0) and females (rate ratio of 1.1)

The onset of hypertensive heart disease is earlier among Aboriginal and Torres Strait Islander people than non-Indigenous people. Aboriginal and Torres Strait Islander people aged 25–34 years were more than three times as likely as non-Indigenous people to have hypertensive heart disease, while for people aged 35–44 years and 45–54 years, the ratios were 1.9 and 1.2, respectively. Aboriginal and Torres Strait Islander people aged 55 years and over were less likely than non-Indigenous people of the same age to have hypertensive heart disease (rate ratio of 0.8).

ENDNOTE

1. Vos T, Barker B, Stanley L, Lopez AD 2007. The Burden of Disease and Injury in Aboriginal and Torres Strait Islander peoples 2003, School of Population Health, The University of Queensland, Brisbane.