Absolute cardiovascular risk

Absolute risk is a term used to define the probability of a person developing a disease within a specified time period. Absolute cardiovascular risk is the chance of an individual developing cardiovascular disease (CVD), which includes all heart, stroke and blood vessel diseases (ACDPA 2020).

An absolute risk approach to disease uses data for multiple risk factors. Assessing CVD risk based on the combined effect of risk factors is more accurate than looking at risk factors in isolation – because of the cumulative or influencing effects of multiple factors – and allows for more tailored risk factor management for each person (NVDPA 2012, Nelson 2020).

The Australian absolute CVD risk calculator is a tool recommended by the Australian Chronic Disease Prevention Alliance for health professionals to measure individual cardiovascular risk.

Banks et al recently estimated that almost 20% of Australians aged 45–74 (1.4 million adults) were at high absolute risk of a future CVD event – such as heart attack, stroke, PVD or heart failure – over the next 5 years. A further 8.6% (625,000) were at moderate risk (Banks et al. 2016).

Of those at high absolute risk who already had CVD, many were not receiving recommended treatment. Less than half (44%) were receiving blood pressure- and lipid-lowering medication, 35% were receiving only one of these, and 20% were receiving neither.

Absolute risk among Aboriginal and Torres Strait Islander people

Based on 2012–13 data, an estimated 16% of Indigenous people aged 35–74 (26,100 adults) were at high absolute risk of a future CVD event (Calabria et al. 2018). Many are undertreated – just over half (53%) of Indigenous people aged 35–74 at high absolute risk who already had CVD were receiving lipid-lowering therapy.

Nationally, as at June 2020, an estimated 34% of regular clients of Indigenous primary health care aged 35–74 with no known history of CVD who had a CVD risk assessment result recorded in the previous 2 years were assessed at high risk, with 5.9% at moderate risk and 60% at low risk (AIHW 2021).

The high risk in the Indigenous population is attributed to the greater prevalence of CVD risk factors than in the general Australian population, particularly of diabetes, dyslipidaemia, chronic kidney disease and smoking (Calabria et al. 2018). High absolute CVD risk was evident at younger ages among Indigenous people than among the general population.