What is rheumatoid arthritis?

Rheumatoid arthritis is a chronic autoimmune disease characterised by inflammation of the joints, causing inflammation, pain, swelling, stiffness and loss of function in the joints. Rheumatoid arthritis most often affects the hand joints and both sides of the body at the same time.

In a healthy joint, the tissue lining the joint (called the synovial membrane or joint synovium) is very thin and produces fluid that lubricates and nourishes joint tissues. In rheumatoid arthritis, the immune system attacks the synovial membrane. The synovial membrane becomes thick and inflamed, resulting in unwanted tissue growth (Figure 1). As a result, bone erosion and irreversible joint damage can occur, leading to permanent disability [1].

Figure 1: Comparison of healthy joint and joint with rheumatoid arthritis

This image compares the anatomy of a healthy joint with a joint affected by osteoarthritis. The image shows muscle wasting, bone destruction, inflamed synovial membrane surrounding the joint, and migration of the synovial membrane onto and into bone and cartilage in rheumatoid arthritis compared with a healthy joint.

Source: AIHW 2015. Musculoskeletal fact sheet: rheumatoid arthritis. Arthritis series no. 24. Cat. no. PHE 188. Canberra: AIHW.

Rheumatoid arthritis is a systemic disease, affecting the whole body, including the organs. This can lead to problems with the heart, respiratory system, nerves and eyes. Its cause is not well understood although there is a strong genetic component. Genetic factors are estimated to contribute 50–60% of the risk of developing rheumatoid arthritis [2].

How common is rheumatoid arthritis?

About 458,000 Australians (1.9% of the total population) have rheumatoid arthritis, based on self-reported data from the Australian Bureau of Statistics (ABS) 2017–18 National Health Survey (NHS). Rheumatoid arthritis represented 13% of all arthritic conditions in 2017–18.

Rheumatoid arthritis is most common in people aged 75 years and over (Figure 2), although the onset of rheumatoid arthritis most frequently occurs in those aged 35–64 [3, 4, 5]. The prevalence of this disease is slightly higher for women (2.3%) compared with men (1.5%).

458,000 (1.9%)

Australians have rheumatoid arthritis

Figure 2: Prevalence of self-reported rheumatoid arthritis, by age and sex, 2017–18

The vertical bar chart shows that the prevalence of rheumatoid arthritis is most common in people aged 75 and over in both males (5%25) and females (8%25) and least common among people aged 0—44 (0.4%25 in males and 0.6%25 in females).

 

Note: refers to people who self-reported that they were diagnosed by a doctor or nurse as having rheumatoid arthritis (current and long term) and also people who self-reported having rheumatoid arthritis.

Source: AIHW analysis of ABS 2019 [6] (Data table).

 

There has been little change in the prevalence over the past 10 years. It is difficult to evaluate the full impact of this condition on affected individuals due to the limited national statistics available.

References

  1. RACGP (The Royal Australian College of General Practitioners) 2009. Clinical guideline for the diagnosis and management of early rheumatoid arthritis. Melbourne: RACGP.
  2. Tobón GJ, Youinou P & Saraux A 2010. The environment, geo-epidemiology, and autoimmune disease: Rheumatoid arthritis. Journal of Autoimmunity 35 (1):10–14.
  3. AIHW (Australian Institute of Health & Welfare) 2009. A picture of rheumatoid arthritis in Australia. Arthritis series no. 9. Cat. no. PHE 110. Canberra: AIHW.
  4. Mayo Clinic 2014. Arizona: Mayo Clinic. Viewed 20 January 2015.
  5. Ruderman E and Tambar S 2012. Atlanta: American College of Rheumatology. Viewed 20 January 2015.
  6. ABS 2019. Microdata: National Health Survey, 2017-18, detailed microdata, DataLab. ABS cat no. 4324.0.55.001. Canberra: ABS. Findings based on AIHW analysis of ABS microdata.