Biomedical risk factors are bodily states that have an impact on a person’s risk of disease. This page focuses on 3 biomedical risk factors: blood pressure, blood lipids and blood glucose—elevated levels of which have been directly linked to specific health outcomes such as cardiovascular disease, including coronary heart disease and stroke, chronic kidney disease and diabetes. Obesity, which is also a biomedical risk factor, is discussed in Overweight and obesity. The information on this page is based mostly on the Australian Bureau of Statistics (ABS) 2011–12 Australian Health Survey, 2014–15 National Health Survey and 2017–18 National Health Survey.  

The most recent national data on blood lipid and blood glucose levels were collected in 2011–12, and subsequent national health surveys have relied on self-reported data. More surveys are needed to continue to monitor the levels of these risk factors in the Australian population over time. The ABS is commencing in 2021 a new Intergenerational Health and Mental Health Survey which will include measurement of biomedical risk factors. 

High blood pressure

High blood pressure—also known as hypertension—is a risk factor for chronic conditions, including heart failure, chronic kidney disease and stroke. In 2015, it was estimated that high blood pressure contributed 65% of hypertensive heart disease burden, 43% of coronary heart disease burden, 41% of stroke burden, 38% of chronic kidney disease burden, and 32% of atrial fibrillation and flutter burden (AIHW 2019).

High blood pressure contributed 5.8% of the total burden of disease in Australia in 2015 and 21% of high blood pressure burden is due to a diet high in sodium (AIHW 2019). See Burden of disease.

In 2017–18, an estimated 34% of adults had high blood pressure. This included 23% who had uncontrolled high blood pressure, and 11% whose blood pressure was controlled with medication (ABS 2019). The proportion of Australian adults with high blood pressure has remained stable since 2011–12. 

Abnormal blood lipids

Abnormal levels of blood lipids, such as cholesterol and triglycerides—also known as dyslipidaemia—can lead to the build-up of fatty deposits in the blood vessels and contribute to the risk of cardiovascular disease. In 2015, it was estimated that high cholesterol contributed 37% of coronary heart disease burden and 15% of stroke burden. High cholesterol levels contributed 3.0% of the total burden of disease in Australia in 2015 (AIHW 2019). See Burden of disease.

Based on self-reported data from the National Health Survey in 2017–18, an estimated 1.5 million adults (7.8%) reported that they had high blood cholesterol levels (ABS 2019). This was lower than the self-reported prevalence in 2014–15, where 9.1% of adults (1.6 million) reported high blood cholesterol levels (ABS 2017).

Self-reported data underestimates the true impact of abnormal blood lipids in the population, as many people are unaware they have abnormal levels. In 2011–12, blood cholesterol levels were measured, via a blood test, to ascertain the prevalence of abnormal blood lipids in the Australian population. Based on these data, an estimated 2 in 3 (65%, or 8.4 million) Australian adults had abnormal blood lipid levels. This included 59% with uncontrolled blood lipids and 6.7% with normal blood lipid levels who were taking lipid-modifying medication (ABS 2014).

Impaired glucose regulation

Impaired glucose regulation is a condition where blood glucose levels are higher than normal, but not high enough to be regarded as type 2 diabetes. People with impaired glucose regulation are at increased risk of diabetes and cardiovascular disease. High blood plasma glucose was responsible for the entire burden of each type of diabetes, 60% of chronic kidney disease burden and 6.7% of coronary heart disease burden. High blood plasma glucose (including intermediate hyperglycaemia and diabetes) contributed 4.7% of the disease burden in Australia in 2015 (AIHW 2019). See Burden of disease.

Based on self-reported data from the National Health Survey in 2017–18, an estimated 99,700 adults reported that they had had high sugar levels measured in their blood or urine. This was around 0.5% of the adult population. This was consistent with results reported in 2014–15.

As for other biomedical risk factors, self-reported data underestimate the true impact of impaired glucose regulation in the population, as many people are unaware they have impaired regulation. In the 2011–12 Australian Health Survey, impaired glucose regulation was assessed via measurement of blood glucose levels after fasting. Based on these results, 3.1% (416,000) of Australian adults were estimated to have impaired glucose regulation.

Multiple biomedical risk factors

Biomedical risk factors can have an interactive or cumulative effect on disease risk. Multiple risk factors can increase the risk of disease, lead to earlier disease onset, increase severity and complicate treatment.

The development of 1 risk factor can lead to the occurrence of another, or they may have shared causes. For example, high blood pressure and abnormal blood lipids are often related to poor diet and being overweight.

In 2011–12, an estimated 1 in 4 (25%) Australian adults had both high blood pressure and abnormal blood lipids. This includes people with measured high blood pressure and abnormal blood lipids, and those who take medication to control these conditions. This increased with age, from 4.3% in people aged 18–34 to 65% in people aged 75 and over. Just over 7 in 10 (71%) adults had either high blood pressure, abnormal blood lipids or both risk factors. This was highest in people aged 75 and over (96%) (ABS 2014).

Managing risk factors

Treating or managing biomedical risk factors includes changes in lifestyle (such as dietary modifications or increased physical activity), use of medications, and surgery. Improving biomedical risk factors can prevent disease, delay disease progression and improve treatment outcomes, and have the potential to enhance the health of the population.

  • In 2017–18, hypertension was the most commonly reported chronic condition at general practice encounters, and abnormal blood lipids was the fourth most commonly reported chronic condition (NPS MedicineWise 2019).
  • In 2017–18, an estimated 23% of adults had measured high blood pressure but were not taking any blood pressure medication. There has been no change in the prevalence of uncontrolled high blood pressure since 2011–12 (ABS 2019).
  • In 2011–12, 87% of people with measured abnormal blood lipids were not using lipid modifying medications. This reflects current guidelines, which state that prescription of lipid modifying medications is not based on abnormal blood lipids alone, but on the absolute risk of cardiovascular disease (RACGP 2018). The absolute risk of cardiovascular disease considers risk factors, such as blood pressure and cholesterol levels, in combination (ABS 2014).
  • In 2011–12, a total of 7.7% of people were identified as having abnormal blood lipids, despite reporting using lipid lowering medications. Poorly controlled blood lipids, despite the use of medication, was highest in people aged 65–74 (20%) (ABS 2014).

Where do I go for more information?

For more information on biomedical risk factors, see:

Visit Risk factors for more on this topic. 

References

ABS (Australian Bureau of Statistics) 2013. Australian Health Survey: users’ guide, 2011–13. ABS cat. no. 4363.0.55.001. Canberra: ABS.

ABS 2014. Microdata: Australian Health Survey, core content—risk factors and selected health conditions, 2011–12. ABS cat. no. 4324.0.55.003. AIHW analysis of Expanded Confidentialised Unit Record File. Canberra: ABS.

ABS 2016. Microdata: National Health Survey, 2014–15. ABS cat. no. 4324.0.55.001. AIHW analysis of Expanded Confidentialised Unit Record File. Canberra: ABS.

ABS 2017. National Health Survey: users’ guide, 2014–15. ABS cat. no. 4363.0. Canberra: ABS.

ABS 2019. Microdata: National Health Survey, 2017–18. ABS cat. no. 4324.0.55.001. Findings based on Detailed Microdata analysis. Canberra: ABS.

AIHW (Australian Institute of Health and Welfare) 2019. Australian Burden of Disease Study 2015: Interactive data on risk factor burden. Australian Burden of Disease series Cat. no. BOD 25. Canberra: AIHW.

NPS MedicineWise 2019. General practice insights report July 2017–June 2018. Sydney: NPS MedicineWise, 2019.

RACGP (The Royal Australian College of General Practitioners) 2018. Guidelines for preventive activities in general practice 9th edn updated. East Melbourne, Victoria: RACGP.