Pulmonary Fibrosis

Pulmonary fibrosis is a lung disease where tissue becomes scarred and thickened, making breathing progressively more difficult. While the exact cause is often unknown, understanding this condition and its management can help improve quality of life for those affected.

Table of contents

• What is pulmonary fibrosis?
• Symptoms
• Causes and risk factors
• How is it diagnosed?
• Treatment options
• Living with pulmonary fibrosis
• Possible complications

What is pulmonary fibrosis?

Pulmonary fibrosis is a lung disease that occurs when lung tissue becomes damaged and scarred. The word “pulmonary” refers to the lungs, and “fibrosis” means scar tissue, similar to scars that form on the skin from an old injury or surgery^[1][3]. This thickened, stiff tissue makes it harder for the lungs to work properly and becomes progressively worse over time^[1].

In healthy lungs, the tissue is spongy and stretchy, allowing air to move in and out easily. At the end of small tubes in the lungs are tiny air sacs called alveoli (the smallest parts of the lung where oxygen and carbon dioxide are exchanged), surrounded by blood vessels. The space between these air sacs and blood vessels is called the interstitium (the tissue space in the lungs between the air sacs and blood vessels)^[6]. When pulmonary fibrosis develops, scar tissue forms in this interstitium and the area becomes thicker, making the lungs stiff and less stretchy^[6].

• Lungs
• Alveoli (air sacs)
• Interstitium
• Blood vessels

Pulmonary fibrosis is part of a larger group of more than 200 diseases called interstitial lung diseases (diseases that affect the tissue between the air sacs in the lungs)^[2][3]. When a specific cause cannot be found, the condition is called idiopathic pulmonary fibrosis (pulmonary fibrosis without a known cause). Most cases of pulmonary fibrosis are idiopathic^[1][2].

IPF, Idiopathic pulmonary fibrosis, Interstitial pulmonary fibrosis, Lung scarring

Symptoms

The symptoms of pulmonary fibrosis tend to develop gradually and get slowly worse over time^[13]. Many people initially ignore their breathlessness and blame it on getting older or being out of shape^[13].

Common symptoms may include^[1][2]:

• Shortness of breath, especially during or soon after physical activity
• Breathing in short, shallow breaths
• A persistent dry cough that doesn’t go away
• Extreme tiredness and weakness
• Unintended weight loss
• Aching muscles and joints
• Widening and rounding of the tips of the fingers or toes, called clubbing
• Bluish, gray or white skin around the lips, eyes or nails

As the disease progresses, eventually even light activities such as getting dressed can cause shortness of breath^[13]. How fast pulmonary fibrosis worsens is different for each person. Some people can stay stable for a long time, but the condition gets worse faster in others^[1].

Causes and risk factors

The scarring that happens in pulmonary fibrosis can be caused by many things. However, doctors and other healthcare professionals often cannot pinpoint what’s causing the problem^[1]. Experts think pulmonary fibrosis happens when the lungs don’t heal properly from damage or inflammation^[2].

From what researchers have learned, two main processes can lead to scar tissue in the lungs. The first is inflammation, when something causes irritation or injury to the lungs. The second occurs when cells in the lungs age too quickly and are unable to repair normally, causing scar tissue to form instead^[6].

Known causes and risk factors include^[2][7]:

• Environmental exposures: Substances like asbestos, silica, beryllium, metal dust, wood dust, or coal dust can cause lung scarring
• Connective tissue diseases: These include rheumatoid arthritis, lupus, and scleroderma
• Medications or treatments: Certain medicines such as amiodarone, nitrofurantoin, methotrexate, and radiation therapy
• Smoking: Tobacco use increases risk
• Viral infections: Some viral infections may contribute
• Granulomatous diseases: These include sarcoidosis
• Hypersensitivity pneumonitis: An allergic reaction to certain molds, bacteria, or bits of bird feathers or droppings

Additional risk factors include^[2][13]:

• Being 65 years old or older
• Being male
• Having a family member with pulmonary fibrosis
• Having gastroesophageal reflux disease (GERD)

In most cases, however, the specific cause is unknown, which is why it is called idiopathic pulmonary fibrosis^[2].

How is it diagnosed?

Diagnosing pulmonary fibrosis may require several tests and procedures. Your healthcare provider will review your medical and family history, perform a physical examination, and ask about your symptoms^[11]. They will inquire about any medicines you take and any continuous or repeated contact with dusts, gases, chemicals, or similar substances, especially through work^[11].

During the physical exam, your healthcare professional listens carefully to your lungs while you breathe. Pulmonary fibrosis often produces a crackling sound at the base of the lungs^[11].

Diagnostic tests may include^[2][11]:

• Chest X-ray: Images may show scar tissue, although sometimes the chest X-ray appears normal
• High-resolution CT scan: A detailed scan that combines X-ray images from many angles to show lung structures and help identify the extent of lung damage
• Pulmonary function tests: Also called lung function tests, these measure how well the lungs are working, including how much air the lungs can hold and how quickly air moves in and out
• Blood tests: Including an arterial blood gas test to measure oxygen levels
• Echocardiogram: A test using sound waves to look at the heart and measure pressure in the lung arteries and right side of the heart
• Bronchoscopy: A procedure where a thin tube with a camera is inserted into the airways to examine the lungs
• Lung biopsy: A small piece of lung tissue is removed during keyhole surgery so it can be examined under a microscope

It might take a number of tests and imaging procedures to diagnose pulmonary fibrosis and rule out other conditions that affect the heart and lungs^[2].

Treatment options

There is currently no cure for pulmonary fibrosis, and the lung damage caused by it cannot be repaired^[1]. However, several treatments can help reduce the rate at which fibrosis worsens, ease symptoms, and improve quality of life^[1][13].

Medications

Two main medicines have been approved to slow the progression of idiopathic pulmonary fibrosis^[15][16]:

• Pirfenidone: An anti-fibrotic and anti-inflammatory drug taken by mouth three times a day that has been shown to slow progression of mild-to-moderate idiopathic pulmonary fibrosis
• Nintedanib: An anti-fibrotic drug taken by mouth twice a day that is approved to treat idiopathic pulmonary fibrosis and certain other types of progressive fibrotic lung diseases

Other medications may be used depending on the type of pulmonary fibrosis. For some forms caused by autoimmune conditions, medications that suppress the immune system may be prescribed^[8].

Oxygen therapy

Supplemental oxygen therapy is used when oxygen levels in the blood are low. This treatment increases the amount of oxygen in the blood, improves symptoms, and allows patients to live longer and healthier lives^[18]. Oxygen can be delivered through a mask or nasal tubes, either at home or while out and about^[13].

Pulmonary rehabilitation

Pulmonary rehabilitation is a program that helps people manage shortness of breath through exercises, breathing techniques, education, nutrition advice, and emotional support^[1]. The program is tailored to individual needs and can help improve quality of life^[8].

Lung transplant

For some people, a lung transplant might be an option when other treatments fail^[1][16]. A lung transplant is the only treatment for pulmonary fibrosis shown to increase life expectancy. It can improve both the quality and length of life^[8][16].

Living with pulmonary fibrosis

If you have been diagnosed with pulmonary fibrosis, it is important to continue your treatment plan and maintain regular follow-up care with your healthcare team^[22]. Taking an active role in your own care frequently leads to better results in the long run^[19].

There are several things you can do to maintain or improve your quality of life^[19][24]:

• Stop smoking: If you smoke, quitting is one of the most important steps you can take
• Eat a well-balanced diet: Proper nutrition plays an important role in managing pulmonary fibrosis by maintaining muscle strength and supporting lung function^[23]
• Exercise regularly: Regular physical activity within your limits can help maintain strength and reduce breathlessness
• Stay hydrated: Drinking enough water helps thin mucus and clear the airways. Many patients recommend drinking 8 glasses of water each day^[21]
• Manage cough and mucus: Some patients find relief using cough lozenges, expectorants like Mucinex, honey, or drinking pineapple juice^[21]
• Avoid lung irritants: Stay away from smoke, dust, strong chemical fumes, and air pollution whenever possible
• Get vaccinations: Keep up to date with flu, pneumonia, and COVID-19 vaccines to prevent respiratory infections
• Prepare for medical visits: Make a list of questions or concerns before appointments and consider bringing someone with you to help remember information^[19]
• Connect with others: Joining support groups can help you feel less isolated and learn from others living with the same condition^[24]
• Look after your mental health: Taking care of your emotional wellbeing is essential. Consider counseling if you are struggling^[8]

It is important to know when to seek medical help. Contact your doctor if you experience a sudden worsening of symptoms over days or weeks, called an exacerbation. If you suddenly have trouble breathing, call emergency services immediately^[8][22].

Possible complications

Scarred lung tissue has a hard time getting oxygen to the rest of the body and can make the heart work harder. This can lead to several complications^[2][22]:

• Low oxygen levels: In the blood and tissues
• Pulmonary hypertension: High blood pressure in the lungs
• Respiratory failure: When the lungs can no longer provide enough oxygen to the body
• Heart failure: The heart becomes unable to pump effectively due to increased pressure
• Collapsed lung
• Lung infections
• Lung cancer: People with pulmonary fibrosis have an increased risk^[7]
• Depression and anxiety
• Sleep problems

Pulmonary fibrosis gets worse over time, although the speed at which this happens varies greatly between individuals. Some people respond well to treatment and remain relatively free of symptoms for many years, while others may experience more rapid progression^[13]. Life expectancy is generally less than five years after diagnosis, although this varies depending on the individual and how quickly the disease progresses^[7].