Over time, rheumatoid arthritis (RA) can lead to lung tissue damage, which can result in a condition doctors call pulmonary fibrosis. With this condition, lung tissue becomes thick and scarred, making it harder to absorb oxygen into the bloodstream.
RA is an autoimmune inflammatory condition that causes chronic pain in the joints. It can also affect other organs, such as the lungs, causing severe breathing problems that health experts call pulmonary fibrosis.
Pulmonary fibrosis is a type of interstitial lung disease. It is part of many different lung conditions that can cause inflammation in the air sacs of the lungs, as well as in lung tissue and the air space between the sacs.
When such a condition also causes scarring, health experts refer to it as pulmonary fibrosis. Scarring can block oxygen from moving from the lungs to the blood. This in turn can lead to shortness of breath, especially when a person is experiencing exertion.
Doctors still do not fully understand the link between RA and pulmonary fibrosis. However, evidence shows that 40% of people with RA have some degree of pulmonary fibrosis.
When RA leads to pulmonary fibrosis, people may experience the following:
- shortness of breath
- persistent dry cough
- frequent feeling of tiredness
- sudden, unexplained weight loss
These symptoms will occur alongside the more common symptoms of RA, which vary in type and severity and may come and go. During a flare, symptoms can vary in duration and intensity.
Common symptoms of RA include:
- stiffness upon waking up that lasts for 30 minutes or longer
- tenderness, pain, or swelling in the joints that lasts 6 weeks or longer
- pain in joints on both sides of the body
- pain in smaller joints, such as in the hands, wrists, and feet
Typically, pulmonary fibrosis and related lung problems develop in people who have lived with RA for several years. This means that doctors usually diagnose RA before pulmonary fibrosis.
However, research shows that 10–20% of people can experience symptoms of respiratory issues before they develop typical RA symptoms.
A person living with RA is more at risk of developing pulmonary fibrosis if they:
- are male
- are an older adult
- have a high level of anti-citrullinated protein antibody in their blood
- have a gene that predisposes them to develop the lung condition
- often come into contact with environmental pollution
- regularly use anti-inflammatory medication
Complications from RA-linked pulmonary fibrosis can become life threatening if a person does not receive prompt treatment.
Typically when a person with RA has lung symptoms, they will need to seek guidance from a rheumatologist and a pulmonologist. Pulmonologists are doctors who specialize in lung conditions.
A person may be able to access an evaluation in a multi-disciplinary clinic where different doctors can work together to examine the person and provide a diagnosis.
- bronchoscopy, to rule out infection
- pulse oximetry
- pulmonary function test, which can involve testing how the lungs respond to a short, 6-minute exercise
- chest X-ray
- lung biopsy, in cases when the doctor wants to exclude lung cancer
- arterial blood gas test
These tests show whether there is inflammation or damage in the lung tissue. They also measure the levels of oxygen, carbon dioxide, and air capacity in the lungs.
If a person does not already have a diagnosis of RA, doctors will also ask about the person’s general medical history, do a complete physical examination, and order additional series of imaging and blood tests.
These tests check for:
- swollen joints
- the degree of pain a person is experiencing
- the presence of antibodies in the blood called rheumatoid factor (RF) and cyclic citrullinated peptide (CCP)
- bone and joint abnormalities
Common tests to diagnose RA
- RF test: This blood test shows the concentration of RF, an autoantibody common in people with RA.
- CCP: This blood test checks for another autoantibody common in people with RA.
- Erythrocyte sedimentation rate (ESR): This test gauges how quickly red blood cells settle to the bottom of a test tube. The ESR test indicates the presence of an inflammatory condition, such as RA, but cannot diagnose RA on its own.
- C-reactive protein (CRP) test: This test indicates the level of CRP in the blood. Higher levels of CRP may indicate inflammation or infection in the body.
- Complete blood count: This test can check for anemia. A 2016 study reports that 60% of Sudanese people with RA in the study also had anemia.
Both RA and pulmonary fibrosis have no cure, so treatment goals aim to manage the symptoms and reduce the progression of the condition.
Medications and treatments to manage RA-linked pulmonary fibrosis
When should I contact a doctor?
If a person with RA has shortness of breath or dry cough, they should seek immediate medical attention.
A doctor will typically recommend regular lung screenings to any person with RA.
In people with confirmed lung disease, screenings will need to continue every
What is the life expectancy for RA-linked pulmonary fibrosis?
According to a 2016 study, life expectancy for someone with primary pulmonary fibrosis is
A 2021 study notes that
However, RA-linked pulmonary fibrosis may not follow the same course that aggressive primary pulmonary fibrosis usually does. Also, there is not enough data to estimate the specific outlook for this specific subset of the condition.
RA-linked pulmonary fibrosis progresses differently from person to person. Some people experience worsening symptoms within months, while in others, the condition may take a few years to advance.
Differences in progression may be because age, genetics, and lifestyle factors play a role in the development of both conditions.
If a person has RA and experiences lung problems, they should contact a doctor at the earliest opportunity about the nature and frequency of symptoms.
Recent advances in medication and treatment have improved both management of symptoms and quality of life in the long term.