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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.
It is estimated that 5 million people suffer from RA in the seven major markets, that is 0.3% to 1% of the general population. Prevalence is not split evenly between genders, since women are more likely to be affected than men.
Although RA can affect people of all ages, the onset of the disease usually occurs between 30-50 years of age.
Doctors are still unable to pinpoint the exact cause of RA. It is thought that genetic, environmental and hormonal factors all play a role.
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, the single cell layer that regulates transport between the joint cavity and its surroundig tissue, are thought to be bacterial and/or viral.
Women get rheumatoid arthritis two to three times more often than men and their RA 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 might play a role in the development and progression of RA. Many are trying to understand the effects female hormones might have in the development of RA. Currently, there are limited answers to these questions.
Symptoms of RA may come and go and vary in severity from patient to patient. The main symptoms are:
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 clear reason why this should be the case, however lack of exercise and mobility are risk factors for developing many of these conditions.
Women are three times more likely to be affected by RA than men