Rheumatoid arthritis (RA) is a progressive immunological disease which causes chronic inflammation of the joints. It generally affects the smaller joints in the body such as fingers, thumbs, wrists, feet and ankles; however the systemic nature of the condition means it can also affect the entire body, including internal organs and the vascular system.
RA is one of a group of conditions classified as autoimmune diseases, where the body mistakenly attacks its own immune system. In RA, inflammatory processes target the tissue that surrounds each joint known as the synovium. This inflammation leads to swelling and damage of cartilage and bones of the synovial-lined joints.
Who is affected?
Over 4.6 million Canadian adults (one in six Canadians aged 15 years and older) report having arthritis. By 2036, this number is expected to grow to an estimated 7.5 million Canadian adults (one in five).
The prevalence of RA is higher in developed countries, and amongst women.
Although RA can affect people of all ages, the onset of the disease usually occurs between 30-50 years of age.
How is it caused?
Doctors are still unable to pinpoint the exact cause of RA. It is thought that genetic, environmental and hormonal factors play a role.
People with specific genes are at an increased risk of developing RA, but having a gene that predisposes to RA does not always lead to the development of the disease.
Many scientists believe there are environmental factors that can trigger the development of RA in susceptible individuals. These triggers, which lead to the immune system attacking the healthy synovium are thought to be bacterial and/or viral.
Women develop rheumatoid arthritis two to three times more often than men. RA in women typically goes into remission when they get pregnant. Women develop RA more often than expected in the year after pregnancy, and symptoms can increase after a baby is born. These facts lead researchers to believe that gender may play a role in the development and progression of RA. Many are trying to understand the effect of female hormones on the development of RA. Currently, there are limited answers to these questions.
Symptoms and associated conditions
Symptoms of RA may come and go and vary in severity from patient to patient. The main symptoms are:
- Joint stiffness
- Joint pain
- Swelling of joints
- Redness and warmth around the joints
- Reduction in mobility
- Appearance of nodules or lumps under the skin
- Deformity of joints.
Patients often experience symmetrical symptoms, whereby any symptoms felt on one side of the body are reflected in the same joints on the other side.
These symptoms often lead to permanent damage of joints and bones. As this damage occurs, patients may find their movement becomes more restricted, and this can lead to difficulty in undertaking even the simplest everyday tasks such as combing hair, turning a doorknob or taking a walk.
RA patients are also at a higher risk of developing other conditions, in particular heart disease and stroke. There is no explanation for this, however lack of exercise and mobility are risk factors for developing many of these other conditions.
How is RA diagnosed?
Diagnosis of RA is not always easy, since initial symptoms may be subtle, occur gradually, and early stage RA shares a number of symptoms with other musculoskeletal diseases. Physicians use a combination of medical history, physical examinations and laboratory tests including blood tests and x-rays / imaging techniques to diagnose RA.
Early diagnosis is important as joint damage begins to occur within the first two years after presence of RA disease. There is currently no cure for RA, and as such, treatment goals centre on disease management.
Please visit the Arthritis Society of Canada for further information about rheumatoid arthritis.