Chronic kidney disease (CKD) refers to all conditions of the kidney affecting the filtration and removal of waste from the blood for 3 months or more. It is identified by reduced filtration by the kidney and/or by the leakage of protein or albumin from the blood into the urine. CKD is frequently comorbid with cardiovascular disease and diabetes (AIHW 2007, 2014).
CKD is mostly diagnosed at more advanced stages when symptoms become more apparent. Kidney failure occurs when the kidneys can no longer function adequately, at which point people require kidney replacement therapy (KRT) – a kidney transplant or dialysis – to survive.
CKD is largely preventable because many of its risk factors – high blood pressure, smoking and overweight and obesity – are modifiable. Other chronic diseases, such as cardiovascular disease and diabetes, are also risk factors for CKD (KHA 2020).
Early detection of CKD by simple blood or urine tests enables treatment to prevent or slow its progression.
How common is chronic kidney disease?
An estimated 11% of people (1.7 million Australians) aged 18 and over had biomedical signs of CKD in 2011–12, according to AIHW analysis of the Australian Bureau of Statistics latest National Health Measures Survey (NHMS) (ABS 2013) – the most recently available data on the total number of people affected by CKD in Australia (the ‘prevalence’).
The prevalence of CKD increases rapidly with age, affecting around 44% of people aged 75 and over (AIHW 2018).
Only 6.1% of NHMS respondents who showed biomedical signs of CKD self-reported having the disease, indicating that CKD is a largely under-diagnosed condition (ABS 2013).
See How many people are living with chronic kidney disease in Australia? for more information on the incidence and prevalence of CKD.
Change over time
Two national surveys have been conducted in Australia that provide data on biomarkers of CKD – the 1999–2000 Australian Diabetes, Obesity and Lifestyle Study (AusDiab) and the 2011–12 NHMS. Note that the ABS is currently undertaking a multi-year Intergenerational Health and Mental Health Study in 2020–2024, which will include a new NHMS and a new National Aboriginal and Torres Strait Islander Health Measures Survey (ABS 2022b).
Between 1999–2000 and 2011–12, the age-standardised CKD prevalence rate remained stable, but the number of Australians with moderate to severe loss of kidney function nearly doubled, from 322,000 in 1999–2000 to 604,000 in 2011–12. This increase was mostly driven by growth in the population of older people (as people live longer) and by survival of people with kidney failure who are receiving KRT (AIHW 2018).
Not everyone with kidney failure chooses to receive KRT, opting instead for end-of-life care. Therefore, estimates of the prevalence of kidney failure need to count cases both with and without replacement therapy. The most recent data available to examine this are linked data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry and the National Death Index, covering the period 1997 to 2013 (AIHW 2016).
There were around 5,100 new cases of kidney failure in Australia in 2013, which equates to around 14 new cases per day. Of these, around 50% were receiving KRT.
Whether people with kidney failure are treated with KRT varies with age. Before age 75, most new cases of kidney failure are treated with KRT; however, this trend reverses after age 75, where there was an 11-fold increase in kidney failure without KRT compared with that for ages 65–74 (from 13 to 145 per 100,000 population) (Figure 1) (AIHW 2016).
In 2013, 92% of people with newly diagnosed kidney failure who were aged under 55 received KRT, compared with 19% of people newly diagnosed aged 75 and over.
Figure 1: Incidence of kidney failure with and without replacement therapy, by age, 2013