Why is it important?:High blood pressure (hypertension) is a risk factor for serious diseases of the circulatory system, including angina and heart attack, stroke, and restricted blood flow to many organs which can lead to deteriorating vision, kidney failure, chronic leg ulcers and gangrene. High blood pressure is much more common among Aboriginal and Torres Strait Islander peoples than non-Indigenous people, and is one of the reasons heart attacks, strokes and other circulatory diseases are much more common, and cause many more early deaths, among Indigenous Australians (AIHW 2002a).
It is estimated that high blood pressure is responsible for 6% of the health gap between Aboriginal and Torres Strait Islander and non-Indigenous Australians (Vos et al. 2007; Vos et al. 2009). Although for some people, the propensity to develop high blood pressure appears to be inherited, it can be prevented or controlled by leading an active and healthy life, remaining fit, avoiding obesity and diabetes and, if necessary, taking regular medication (Passey et al. 2010). For those who have developed high blood pressure, treatment with long-term medication can reduce the risk of developing serious complications. Reducing the prevalence of high blood pressure in Aboriginal and Torres Strait Islander peoples is one of the most important means for reducing serious circulatory diseases.
Findings:There are currently no national data available for the prevalence of high blood pressure in Australia. The 2011–13 Australian Health Survey will include measured blood pressure. For this report, three national data sources provide an indirect indication of the relative prevalence of high blood pressure in Aboriginal and Torres Strait Islander peoples compared with other Australians.
In 2004–05, 7% of Aboriginal and Torres Strait Islander Australians reported having high blood pressure. After adjusting for differences in age structure, Indigneous males and females reported having high blood pressure at 1.4 and 1.6 times the rate of non-Indigenous males and females. There was no significant change in self-reported high blood pressure for Aboriginal and Torres Strait Islander peoples between 2001 and 2004–05. Self-reported data under-estimates prevalence as not everyone who has the condition will have been diagnosed.
Some population studies have shown significantly higher rates of high blood pressure for Aboriginal and Torres Strait Islander peoples. One study in selected remote communities found rates that were 3–8 times as high as the general community (Hoy et al. 2007; Kondalsamy-Chennakesavan et al. 2008).
Few people with high blood pressure require hospitalisation for this condition alone. Most people with high blood pressure are treated by GPs or medical specialists. Therefore, hospitalisation rates for high blood pressure significantly underestimate its prevalence in the community. Hospitalisation rates for high blood pressure were 2.6 times as high for Aboriginal and Torres Strait Islander peoples as for other Australians. This may indicate that the prevalence of severe high blood pressure is more common in Indigneous Australians from a younger age. It may also indicate that high blood pressure is not controlled as well for Indigenous people, so that very severe disease requiring acute care in hospital is more common among this group than among other Australians. Current hospitalisation rates for Indigenous Australians with a principal diagnosis of hypertenisive diease have declined in comparison to rates during 2004–06.
Compared with other Australians, Aboriginal and Torres Strait Islander peoples have similar GP attendance rates for high blood pressure. High blood pressure was a reason for consultation in 4% of GP consultations for Aboriginal and Torres Strait Islander patients.
Implications:Self-reported prevalence and hospitalisation rates for high blood pressure are both higher for Indigenous Australians than other Australians, but high blood pressure accounts for a similar proportion of GP consultations for each population. This suggests that Indigenous Australians with high blood pressure attend their GPs less regularly than other Australians with the same disease and/or their blood pressure is less well controlled.
Hospitalisation rates indicate that severe high blood pressure problems are more common for Indigenous Australians. This suggests that high blood pressure has a higher prevalence in this population or that high blood pressure is poorly controlled and more likely to require acute care. The importance of primary care services to detect and treat high blood pressure in Indigenous Australians is clear, so that severe high blood pressure can be avoided and complications prevented.
Research into the effectiveness of quality improvement programs in Aboriginal and Torres Strait Islander primary health care services has demonstrated that blood pressure control can be improved by a well-coordinated and systematic approach to chronic disease management (e.g. McDermott et al. 2004). Identification and management of hypertension requires access to primary health care with appropriate systems for early detection and chronic illness management. High blood pressure is one of the conditions targeted through various initiatives, including Healthy for Life, designed to improve management of chronic illnesses (see measures 3.03, 3.04 and 3.16).
The National Partnership Agreement on Closing the Gap in Indigenous Health Outcomes (COAG 2008c) comprises various reforms including a focus on preventive health and primary health care. The Commonwealth’s contribution to the Agreement, the Indigenous Chronic Disease Package, includes measures that will help to increase the uptake of MBS-funded primary health care services by Aboriginal and Torres Strait Islander peoples, with approximately 130,000 additional adult health checks being provided over the four years to 2012–13. Assessing blood pressure is one of the key elements of an adult health check.
Table 13 – Aboriginal and Torres Strait Islander people reporting high blood pressure or hypertension, by sex and remoteness, 1995, 2001 and 2004–05
Source: ABS & AIHW analysis of 1995 and 2001 National Health Surveys (Indigenous supplements) and 2004–05 National Aboriginal and Torres Strait Islander Health Survey
Figure 18 – Persons reporting high blood pressure, by Indigenous status, sex and age, 2004–05
(a) Total is age-standardised.
Source: ABS & AIHW analysis 2004–05 National Aboriginal and Torres Strait Islander Health Survey and 2004–05 National Health Survey
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Figure 19 – Age-specific hospitalisation rates for a principal diagnosis of hypertensive disease, by Indigenous status and sex, NSW, Vic., Qld, WA, SA and NT, July 2006–June 2008
Source: AIHW analysis of National Hospital Morbidity Database
Text description of figure 19 (TXT 1KB)