How does RA affect different parts of the body?
Rheumatoid arthritis (RA) causes a person's immune system to mistakenly attack healthy tissue. When left untreated, RA can have wide-ranging effects.
Along with the joints, RA can affect many of the body's organs, including the heart, eyes, and brain, as well as the skeleton. Medication for RA can also cause side effects across the body.
In this article, we look at RA's diverse range of impacts. We also discuss the long-term effects of RA on the body and the likely outcomes.
Which body parts are affected by RA?
RA is an autoimmune disease. Doctors also classify it as a systemic disease because of the extensive changes it can make to different parts of the body.
Image credit: Stephen Kelly, 2018
RA can affect any joint in the body, and it commonly develops in the fingers, hands, and feet.
The condition can also affect joints in the:
- neck and its vertebrae
RA primarily targets the lining of the joints, called the synovium. The condition causes the synovium to become inflamed and swollen.
When the lining of a joint swells, it can lead to stiffness, pain, and a loss of mobility. People often experience joint pain and stiffness in the mornings, and this can be one of the first signs of RA.
The joints contain cartilage, which prevents the bones from rubbing together. Over time, inflammation from RA can cause the cartilage to break down.
If the bones rub against one another, it can permanently damage the joint. This is a significant cause of pain and stiffness in people with advanced RA.
Rheumatoid arthritis can also cause the bones to lose density, becoming thinner and more brittle. This increases the risk of breaks and fractures.
In as many as 20 percent of people with RA, rheumatoid nodules form near the joints. These are small, firm bumps made of inflammatory tissue.
Rheumatoid nodules develop under the skin, over bony areas. While they are often painless and are generally not a cause for concern, they can cause discomfort if a person places pressure on them, such as when kneeling.
RA can also cause inflammation in the skin, sometimes leading to:
- red patches
- ulcers or lesions
When RA affects the skin, a person may notice symptoms ranging from harmless red dots to ulcers on the legs or under the nails.
They may also notice that wounds heal more slowly than usual. Many factors can cause longer healing times in people with RA, including vasculitis, or inflammation of the small blood vessels in the skin.
Some RA medications can also cause skin rashes.
Having RA increases a person's risk of developing Sjogren's syndrome, which causes dryness in the eyes and mouth. Like RA, Sjogren's syndrome is an inflammatory autoimmune disorder.
RA can also cause saliva ducts to narrow or close, leading to an uncomfortable feeling of dryness in the mouth and difficulty eating and swallowing.
Chronic dry mouth can also contribute to gingivitis and tooth decay.
RA can also cause inflammation in the eyes, as well as dry eye syndrome, which can lead to ongoing irritation and eventually damage the cornea.
The effects of RA on the eyes can include:
- keratitis sicca, or dry eye syndrome
- scleritis, or inflammation of the whites of the eyes
- uveitis, or inflammation of the inner eye
- retinal vascular occlusion, or blocked blood vessels in the eye
- glaucoma, which damages the optic nerve
- cataracts, which results from inflammation in the optic lens
In around 80 percent of people, RA affects the lungs. The effects are usually not severe enough to cause symptoms. However, prolonged inflammation in the lungs can lead to pulmonary fibrosis, which can cause scarring and breathing difficulties.
Rheumatoid nodules can also form in the lungs, though these are not usually a cause for concern.
Inflammation from RA can damage the heart and blood vessels. In some cases, the consequences are life-threatening.
RA can cause the following complications:
- Anemia: Unchecked inflammation can lead to iron-deficiency anemia. This refers to a low level of red blood cells, and it can cause headaches and fatigue.
- Atherosclerosis: Chronic inflammation can damage the walls of the blood vessels. This can cause the body to absorb more cholesterol, which can cause plaque to build up inside the arteries. The medical term for this is atherosclerosis.
- Heart attack or stroke: If plaque builds up and blocks an artery or another blood vessel, a heart attack or stroke can result.
- Pericarditis: RA can cause inflammation in the lining of the heart (the pericardium), and this can lead to chest pain.
RA causes inflammation and swelling, which can compress the nerves in the area. When this occurs, a person may notice numbness or tingling in the hands or feet.
When RA develops in the wrist, it can lead to carpal tunnel syndrome. This occurs when inflamed tissue in the wrist squeezes a nerve that extends from the forearm.
RA can develop in the joints of the toes.
If RA affects the feet, it can limit a person's mobility. Because the feet bear the entire weight of the body, the pain from RA can become severe.
The condition often develops in the joints of the toes and, less commonly, the ankles.
RA in the feet can also lead to:
- Inflamed bursae: These fluid-filled sacs often appear on the balls of the feet and can cause chronic pain.
- Nodules: These small, firm lumps can form on the pad of the heel, the Achilles tendon, and other bony areas.
- Corns and calluses: These patches of hard, thick skin tend to develop as the shape of the foot changes. They can lead to ulcers if a person does not receive treatment.
- Nerve compression: When RA damages a joint, this can compress the surrounding nerves and cause numbness and tingling.
- Circulation problems: Inflammation in the blood vessels and joint damage can block the flow of blood to the feet. The feet or toes may become numb easily or develop a bluish tinge.
The mind and brain
Many people with RA may experience psychological or neural symptoms, including:
- brain fog
- cognitive issues
- changes in behavior
These symptoms may arise:
- as side effects of medication
- as a result of body-wide inflammation
- when damage to the bones in the joints leads to a compression of nearby nerves
The kidneys and liver
Prescription medications for RA can cause complications, including liver and kidney damage. This can result from long-term use of painkillers or anti-inflammatory medications.
Long-term effects of rheumatoid arthritis
Rheumatoid arthritis is a progressive disease. This means that if a person does not receive treatment, the symptoms usually get worse.
Over time, a person may notice symptoms in other joints or parts of the body. Or, existing symptoms may grow more severe.
RA causes inflammation in one or more joints. This can cause the cartilage in the joints to wear away. As a result, the bones may rub together and eventually start to erode, causing permanent damage.
Medications can slow the progression of the disorder. In more advanced cases, surgery or joint replacements can help.
RA can be unpredictable. In the long term, people with RA may notice:
- changes in the severity and frequency of symptoms
- periods in which symptoms flare up, which can become more or less frequent
- periods of remission that vary in length
When RA progresses, a person experiences more frequent symptoms, and pain often grows worse.
Below are common indications that RA is progressing:
- pain and swelling increasing
- pain and swelling occurring more regularly
- other symptoms arising more frequently and lasting for longer periods
- symptoms appearing in new areas
- blood tests recording higher levels of rheumatoid factor
If a person notices new symptoms, or if symptoms worsen or appear more frequently, they should contact a doctor.
People with progressive RA often benefit from a tailored treatment plan. The doctor will build this according to the person's symptoms and history. Treatment can also involve specialists in different areas.
Every person with RA has a different experience. Fortunately, many treatments and therapies are available, and a person often benefits from a combination of these. For some people, surgery can also help.
Typically, a doctor will monitor any changes in the condition with testing that may involve blood work or imaging.
Treatment will focus on minimizing pain, slowing the progression of RA, and optimizing a person's mobility.