Who gets rheumatoid arthritis?

About 407,900 Australians (2% of the total population) reported having rheumatoid arthritis, based on self-reported data from the ABS 2014–15 National Health Survey (NHS).

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.

The onset of rheumatoid arthritis most frequently occurs in those aged 35–64 [1, 2, 3]. It is most common in those aged 65 or over and least common among those aged 0–15 (Figure 1). The prevalence of this disease is slightly higher for women (1.7%) compared to men (1.4%).

Figure 1: Prevalence of rheumatoid arthritis, by age and sex, 2014–15

The vertical bar chart shows that the prevalence of rheumatoid arthritis is most common in people aged 65 and over and least common among people aged 0—15.

Source: AIHW analysis of ABS Microdata: National Health Survey, 2014–15 (Data table).

Rheumatoid arthritis comorbidities

People with rheumatoid arthritis often have other chronic conditions. ‘Comorbidity’ is the term used when two or more health conditions occur at the same time. For this analysis, the selected comorbidities are cardiovascular disease (CVD) back problems, mental health problems, asthma, diabetes, COPD and cancer using self reported data from the ABS National Health Survey 2014–15.

Among people with rheumatoid arthritis:

  • 50% reported also having CVD compared with 18% of people without rheumatoid arthritis
  • 32% reported also having back problems compared with 16% of people without rheumatoid arthritis
  • 19% reported also having mental health problems compared with 11% of people without rheumatoid arthritis

(Note, these components do not total 100% as one person may have more than one comorbidity).

Most chronic diseases are more common in older age groups. The average age of people with rheumatoid arthritis is older than the average age of the general population, so people with arthritis are more likely to have age-related comorbidities. After adjusting for differences in the age structure of people with and without rheumatoid arthritis, the rates of CVD and mental health problems as comorbidities remained significantly higher for people with rheumatoid arthritis compared to those without. There was no significant difference for back problems, asthma, diabetes, cancer or COPD. It is important to note that regardless of the differences in age structures, having multiple chronic health problems or ‘comorbidities’ is often associated with worse health outcomes [4], in addition to a poorer quality of life [5] and more complex clinical management and increased health costs.

Some comorbidities, such as CVD, also reflect the underlying prevalence of these individual chronic conditions in the population.

Figure 2: Prevalence of other chronic conditions in people with rheumatoid arthritis, 2014–15

The vertical bar chart shows that people with rheumatoid arthritis often have other chronic conditions such as, CVD (50%25), back problems (32%25), and mental health problems (19%25), diabetes (17%25), asthma (15%25), chronic obstrucutiv pulmonary disease (COPD) (9.6%25), and cancer (4.4%25).

Source: AIHW analysis of ABS Microdata: National Health Survey, 2014–15 (Data table).

Aboriginal and Torres Strait Islander people

According to self-reported data from the ABS 2012–13 Australian Aboriginal and Torres Strait Islander Health Survey (AATSIHS), Indigenous Australians were 1.4 times as likely to have rheumatoid arthritis as total Australians. This difference was not statistically significant.

Figure 3: Prevalence of rheumatoid arthritis by Indigenous status, 2012–13

The vertical bar chart shows that, after adjusting for age, Indigenous Australians were 1.4 times as likely to have rheumatoid arthritis as total Australians. The difference was not statistically significant.

Notes: Rates are age-standardised to the Australian population as at 30 June 2001.

Source: AIHW analysis of ABS Australian Aboriginal and Torres Strait Islander Health Survey (unpublished), 2012–13 (Data table).

References

  1. AIHW (Australian Institute of Health & Welfare) 2009. A picture of rheumatoid arthritis in Australia. Arthritis series no. 9. Cat. no. PHE 110. Canberra: AIHW.
  2. Mayo Clinic 2014. Arizona: Mayo Clinic. Viewed 20 January 2015.
  3. Ruderman E and Tambar S 2012. Atlanta: American College of Rheumatology. Viewed 20 January 2015.
  4. Parekh AK, Goodman RA, Gordon C et al. 2011. Managing multiple chronic conditions: a strategic framework for improving health outcomes and quality of life. Public Health Reports 126:460–471.
  5. McDaid O, Hanly MJ, Richardson K et al. 2013. The effect of multiple chronic conditions on self-rated health, disability and quality of life among the older populations of Northern Ireland and the Republic of Ireland: a comparison of two nationally representative cross-sectional surveys. British Medical Journal Open 3:e002571. doi:10.1136/bmjopen-2013-002571.