Rheumatoid arthritis

Rheumatoid arthritis (RA) is a progressive 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 that it can also affect the body as a whole, 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 leads to swelling and damage of cartilage and bones  of the synovial-lined joints.

Who is affected?

It is estimated that 5 million people suffer from RA globally, and 0.3% to 1% of the population in industrialised countries. Prevalence is not split evenly between genders, since women are three times more likely to be affected than men. 

Although RA can affect people of all ages, the onset of the disease usually occurs between 35-55 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 all play a role.  RA is not necessarily passed from generation to generation.  People with specific genetic markers 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 that 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.

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
• Redness and warmth around the area affected
• 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. In more severe cases RA can eventually lead to disability, and given the age of the average RA patient, the cost of work- related disability is usually a larger societal burden than the cost of RA treatment.

RA patients are also at a higher risk of developing other conditions, in particular heart disease, stroke, infections, lung problems and osteoporosis. There is no clear reason why this should be the case, however lack of exercise and mobility are risk factors for developing many of these conditions.