What is RA? (Part 1)

Rheumatoid arthritis is an auto-immune disease, meaning that the symptoms such as pain and inflammation are caused by the immune system attacking the joints.

Rheumatoid arthritis (RA)

and Osteoarthritis (OA)

The word arthritis simply means ‘inflammation of the joint’. The reasons for that inflammation, however, varies. In the case of osteoarthritis, the cause is ‘wear and tear’. RA is an auto-immune condition, meaning that the immune system, normally there to protect us, is attacking healthy joints.

What is rheumatoid arthritis?

If you say ‘arthritis’ most people assume you’re talking about wear and tear on the joints, which many older people have. That’s osteoarthritis. Rheumatoid arthritis, or RA, is different, as the diagram shows.

It is a type of disease known as an autoimmune condition. This means that your body’s immune system has made a mistake and picked a wrong target. To explain: your immune system is designed to defend your body against infection. It should not attack your body. Sometimes the immune system becomes too active, and mistakenly attacks your body, and this is called ‘autoimmune’ disease. When you have RA, your immune system attacks the lining of your joints (the synovial lining). This causes inflammation, which leads to symptoms such as pain and stiffness. RA is generally a symmetrical arthritis, meaning that it usually affects both sides of the body in a similar pattern, although this is not always the case. It tends to affect the small joints of the hands and feet first – often the knuckle joints in the fingers. It is described as a polyarthritis, meaning that many joints can be inflamed. RA is a systemic disease, meaning that it doesn’t just affect joints. RA can affect a person’s whole system, including organs such as the lungs, heart and eyes. About 1% of the population in the UK has RA – more than 400,000 people in the UK. It affects more women than men, roughly two to three times as many women. The most common age for people to develop RA is between 40 and 60, or a bit older for men. But people can get it at any age, even from the age of 14 when it’s ‘early onset’ RA. There are other forms of inflammatory arthritis, but RA is the most common.

If RA is not treated or is inadequately treated, it can cause irreversible damage to joints and lead to disability – and this used to happen often. But today, the management of RA is very good, far better than it was even 15 years ago. Although there is no cure, most people diagnosed today can expect to lead

What are the symptoms?

Pain is a significant symptom for most people. At first, it is caused by the inflammation in the joints, and later on pain can be as a result of damage to the joints. Pain levels can also vary from day to day. Stiffness is most marked/severe first thing in the morning and it can last several hours if you’re not taking effective medication.

There’s a ‘gelling’ of the joints, meaning that they become difficult to move from a position after you’ve rested them. This also happens when you have been sitting for any length of time. Fatigue can be due to anaemia (low haemoglobin levels in the blood) but it can also be due to the inflammation. It has been linked to a number of things including pain levels. Some people get flu-like symptoms with fever and muscle pains as well as being tired, especially in the early days before or during diagnosis. Quite often people feel low, sad or depressed, because of RA’s overall effect on their body and the pain they are experiencing. And, understandably, because RA is a lifelong condition and there isn’t yet a cure. But there are now very effective treatments.

What causes RA?

We know what causes inflammation in RA and how to treat it effectively. But we don’t yet know exactly what causes RA itself. What we do know is that there are two elements involved: genetics and environmental factors. Genetics are involved even if you don’t have anyone in your family with RA. This has been extensively studied. But it’s not all about genes, genes indicate increased risk/susceptibility but not everyone with these genes develops RA as we can see from studies of identical twins. If one identical twin has RA, the other has only a one in six chance of developing the disease, even though they have the same genes. An environmental trigger can be a virus, infection, trauma of some kind, or having a very stressful episode in your life such as bereavement, divorce or childbirth. There are many theories about triggers but nothing’s been conclusively identified. We know that smoking makes RA more likely. A combination of smoking and having certain genes increases the risk of developing RA considerably, and the disease is more aggressive if it does occur. So if you do smoke, this is another good reason to give up. There’s a huge amount of research being done around the world to find the cause of RA, and many doctors think this will ultimately lead to a cure.

Getting a diagnosis

There is no single test that detects RA. Diagnosis is almost always made or confirmed by a consultant rheumatologist who is trained to identify synovitis, the swelling of joints. This can be very difficult for the untrained eye to see. The rheumatologist also takes other information into account:

What symptoms have you been having? (e.g. joint pain, stiffness and swelling).

Can blood tests help? Your blood may show signs of inflammation (a raised ESR or CRP). One sign is something called rheumatoid factor in the blood, but it isn’t conclusive. About 30% of people with RA don’t have rheumatoid factor, and people with some other conditions can have rheumatoid factor too. Another blood test, for something called anti-CCP antibody, is more specific for RA. But blood tests don’t tell the whole story.

Are there signs of joint damage? If damage is already visible on x-rays you have had inflammation in your joints for some time. You may also have an ultrasound scan, especially if there’s any doubt about whether there is inflammation of the joints (for example, you have lots of pain but no obvious swelling). Less often, doctors use Magnetic Resonance Imaging (MRI) scans, as these can detect inflammation and damage more accurately and earlier than x-rays.

Do you have any family history of inflammatory arthritis? You can’t directly inherit RA, but if it’s in your family you may be more susceptible to getting it when an environmental trigger occurs. (National Rheumatoid Arthritis Society [nras]) (This is a repeat).