Diabetes: Australian facts

What is a risk factor?

Risk factors are attributes, characteristics or exposures that increase the likelihood of a person developing a condition or health disorder. Behavioural risk factors are health-related behaviours that individuals have the most ability to modify. Behavioural risk factors for type 2 diabetes include:

• diet
• physical activity
• smoking.

Biomedical risk factors are bodily states that have an impact on a person’s risk of disease. Biomedical risk factors for type 2 diabetes include:

• impaired fasting glucose and impaired glucose tolerance
• high blood pressure (also known as hypertension)
• dyslipidaemia 
• overweight and obesity
• waist circumference.

Some biomedical risk factors can be influenced by health behaviours.

Fixed risk factors cannot be modified. Fixed risk factors for type 2 diabetes include:

• ageing
• sex recorded at birth
• family history of diabetes (through inherited genes or through sharing an environment of risky health behaviours)
• ethnic background.

Fixed risk factors for type 1 diabetes include family history of type 1 diabetes but the exact cause is unknown at this time. There are no behavioural risk factors which increase the risk for type 1 diabetes, although maintaining a healthy lifestyle is important for managing the symptoms and long-term complications associated with the condition.

Other non-traditional risk factors such as living with a mental health condition can also increase the risk of developing all diabetes types, excluding type 1 (Lindekilde et al. 2021). In addition, Australians with all diabetes types are more likely than other Australians to have poor mental health and wellbeing (AIHW 2011). These effects can arise directly, through biological pathways including the side effects of medications, and indirectly, through health behaviours.

Some factors involved in developing type 2 and gestational diabetes are not linked to behavioural risk factors. However, both conditions are associated with behavioural and biomedical factors that increase the risk of diagnosis and related complications. Clustering of biomedical risk factors with a common underlying cause, as found in metabolic syndrome, also increases the risk of developing type 2 diabetes (Harris 2013).

The Australian type 2 diabetes risk assessment tool (AUSDRISK) is a short list of questions assessing both behavioural and biomedical risk factors which can assess the risk of a person developing type 2 diabetes over the next 5 years. It evaluates both behavioural and biomedical risk factors for diabetes.

For most behavioural and biomedical risk factors there is no known threshold at which risk begins. The relationship between risk and disease is continuous – there is an increasing effect as exposure to the risk factor increases. Having multiple risk factors further escalates risk. 

Many chronic conditions, including diabetes, share behavioural and biomedical risk factors. Modifying behavioural risk factors can reduce an individual's risk of developing type 2 diabetes prematurely and result in substantial health benefits by reducing illness and mortality rates.