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 (CDC 2019).

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 (RACGP 2009). In rheumatoid arthritis, the immune system attacks the synovial membrane (RACGP 2009). 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 (RACGP 2009).

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 rheumatoid arthritis. 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.

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 (CDC 2019). Its cause is not well understood although there is a strong genetic component (CDC 2019). Genetic factors are estimated to contribute 50-60% of the risk of developing rheumatoid arthritis (Tobón et al. 2010).

How common is rheumatoid arthritis?

An estimated 456,000 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) (ABS 2018). 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 (AIHW 2009; Duarte-Garcia 2019). The prevalence of this disease is 1.5 times higher in women (2.3%) than men (1.5%).

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 (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.