It is caused by your body producing antibodies which attack the lining of the joints (more specifically the synovial lining,) leading to pain and inflammation in affected areas. Left untreated, joint damage can develop and become irreversible.
RA is the second most common form of arthritis, affecting 690,000 people in the UK. Osteoarthritis, the degeneration of joints as the result of wear and tear, is the most common type of arthritis.
RA is believed to be caused by a combination of genes and environmental triggers. Your genes can give you a predisposition to RA, and having a close relative with the condition increases your risk. But not everyone with these genes develops RA. In studies of identical twins, if one twin has RA the other one had only a one in six chance of developing it.
Environmental factors, including a viral infection, trauma, hormonal changes or a particularly stressful event (e.g. bereavement) are thought to be triggers in those at genetic risk, but how this happens isn't fully understood. Smoking is known to increase the risk of RA, and the disease also appears to be more aggressive in smokers.
Typical symptoms include pain, swelling and stiffness of the joints. The small joints in the hands and feet are usually the first joints to be affected.Stiffness is worse first thing in the morning and after resting, and takes longer than 30 minutes to wear off.
Symptoms are usually, but not always, symmetrical (affecting both sides of the body).
Other symptoms can include extreme tiredness and fatigue, fever, a high temperature, aching muscles and weight loss. Occasionally, inflammation develops in other parts of the body such as the lungs, heart, blood vessels or eyes.
More than 10 per cent of people with RA report feeling depressed.
RA generally has a pattern of painful flare-ups followed by spells of remission. Damage may be done to the affected joints during each flare-up, so the quicker RA is diagnosed and treated, the better. The British Society for Rheumatology says outcomes are best if RA is treated within the first 12 weeks of symptoms beginning.
This can be difficult as many people initially put their symptoms down to ‘just overdoing it’ and don’t get medical help.
A blood test can detect rheumatoid factor (RF), a protein produced by the immune system which can attack healthy tissue. Although two out of three people with RA have RF, around one in 20 of the normal population also has this protein – so it's not a definitive test.
More recently, a blood test has been developed to detect anti-CCP (cyclic citrullinated peptide) antibody, and provides a more specific diagnosis of RA.
If your doctor suspects RA they will send you to a rheumatologist who is trained to identify synovitis (inflammation of the joint lining), or swelling of the joints. X-rays can confirm damage and MRI scans reveal inflammation.
Who gets RA?
Around one per cent of the UK population has RA. It affects roughly two to three times as many women as men, and the peak age for starting with symptoms is in your 30s and 40s, though it can affect any age. Those with a close relative with the condition and smokers are more at risk.
Drug treatments include non-steroidal anti-inflammatory drugs (NSAIDs), including ibuprofen, to ease pain and stiffness.
The next step is disease-modifying anti-rheumatic drugs (DMARDs), such as methotrexate, which help reduce underlying inflammation and prevent joint damage. DMARDs can take a few weeks to kick in so you may be prescribed corticosteroids injections until they do.
Biological or biologic medicines mimic substances found in the body, such as antibodies and enzymes, and work by blocking chemicals involved in inflammation. They may be the next course of treatment if DMARDs don't work.
Physiotherapy and occupational therapy can help with maintaining joint flexibility, and you may be referred to a podiatrist for help with joint pain in your feet. Sometimes, surgery including joint replacement may be needed.
General lifestyle factors such as keeping well, gentle exercise and eating healthily may also help. The omega 3 fatty acids in fish oil have also been found to help RA symptoms.