How Steroids Can Prevent COPD Flare-Ups and Help You Recover from Exacerbations
The primary purpose of most COPD medications is to help relieve the normal, everyday symptoms of COPD, such as coughing and shortness of breath. Steroid medications, however, contribute to COPD treatment in an entirely different way.
Corticosteroids, the main type of steroid medication used to treat COPD, are mainly used to treat COPD exacerbations, which occur when COPD symptoms temporarily get worse. Steroids don't help much with daily, baseline COPD symptoms, but they are effective for managing the episodes of abnormally severe symptoms that occur during exacerbations.
That's not to say that steroids aren't an important part of COPD treatment, because they are; managing exacerbations is an integral part of controlling COPD symptoms and slowing lung function decline. Steroid medications play a vital role on this front, as both a treatment for exacerbations and as a preventative to reduce the risk of future exacerbations.
There are two main types of steroid medications used in COPD treatment: inhaled corticosteroids (the kind you take via inhaler or nebulizer) and systemic corticosteroids (the kind you usually take as a pill). Using systemic steroids during an acute exacerbation can help you recover faster, while using inhaled steroids daily can reduce how frequently you experience acute exacerbations of COPD.
In this post, we're going to tell you all about steroid medications and COPD so you can better understand the role that they play in COPD treatment. We'll discuss how inhaled and systemic steroids differ, how they help stabilize COPD symptoms, and explain how they work in the body to combat inflammation and keep exacerbations under control.
COPD & Inflammation: An Inflammatory Disease
The main purpose of corticosteroid medications in general is to fight inflammation, and inflammation just so happens to be inextricably intertwined with COPD. Because of this, you won't be able to fully appreciate the importance of steroids in COPD treatment until you first understand the massive role that inflammation plays in the disease.
Research shows that inflammation is a defining characteristic of COPD; people with COPD have inflammation in their lungs, in their airways, and even in their bloodstreams. In fact, COPD is defined by some researchers as an “inflammatory airway disease,” and exerts believe that unchecked inflammation might be a fundamental cause of the disease.
Let's take a closer look at the relationship between COPD symptoms and inflammation to help you better understand how steroid medications help people with COPD.
Lung and Airway Inflammation
Inflammation affects many aspects of COPD, but perhaps the most obvious is the way it triggers respiratory symptoms like coughing, shortness of breath, and excess mucus build-up in the airways. In fact, many of the respiratory symptoms associated with COPD are related in some way to inflammation.
Inflammation, also known as the inflammatory response, is part of the body's natural immune response. Its purpose is to help your body recover and repair itself whenever cells are harmed by injury, irritation, or infection.
Usually, the inflammatory response is only temporary, and eventually shuts down on its own—this is known as acute inflammation. However, it can be harmful if it goes on too long—causing a condition known as chronic inflammation—and even cause serious damage to healthy tissues and cells in your body.
People with COPD have lungs and airways that stay continually inflamed, even when there's no external “reason” for the inflammation such as breathing in an irritant like tobacco smoke. This is one of the reasons why COPD symptoms don't go away even if you quit smoking (though it does have many other benefits); the inflammation—and the lung damage caused by inflammation—continues to persist even after you remove any obvious sources of lung irritation.
This chronic inflammation triggers a variety of different changes in the lungs and airways that cause COPD symptoms to appear. Many of these changes occur on the insides of the small airways in your lungs, which are called your bronchial tubes.
When the bronchial tubes get inflamed, they respond by secreting more mucus than usual. This is a defense mechanism meant to trap and neutralize any pathogens (e.g. viruses and bacteria) or other particles that make it into the lungs to prevent them from causing any further damage to lung and airway tissues.
Usually, that mucus and anything trapped in it gets moved up and out of the airways, where it eventually leaves the body as sputum: the mucus-saliva mixture that comes up when you cough. However, COPD—and the constant inflammation that comes with it—causes additional problems that make it difficult to get this extra mucus out of the airways.
First, COPD damages tiny hair-like structures (called cilia) that line the insides of your airways, which are usually responsible for moving mucus up and out of the lungs. Second, inflammation causes your airways to swell, which narrows the space inside; this causes mucus to get stuck inside the airways, causing even more obstruction that prevents air from flowing through.
All of this together results in the classic airway obstruction associated with COPD: narrowed airways and excess mucus block the flow of air, limiting how much can flow in and out of your lungs at a time. This, in turn, is a major reason for COPD symptoms: shortness of breath, chronic cough, and excess sputum production.
Inflammation also makes the airways hyper-sensitive, causing them to over-react to any irritants breathed into the lungs. This is why people with COPD are so vulnerable to pollution and other airborne irritants; even slight exposure can trigger elevated inflammation that worsens respiratory symptoms.
While inflammation is part of your immune system's defensive response, chronic, unchecked inflammation—like that caused by COPD—can actually do serious harm, causing permanent scarring and other damage to healthy tissues over time. In people with COPD, chronic lung inflammation causes permanent lung and airway damage that is largely responsible for the inevitable and irreversible lung function decline that occurs as the disease progresses.
Research shows that COPD-related inflammation is not just limited to the lungs and airways; COPD causes chronic inflammation all throughout the body. This type of inflammation, known as systemic inflammation (“systemic” meaning “affecting the entire body"), is measured by looking for specific substances called inflammatory markers in the blood.
Long-term, systemic inflammation can have many negative health effects, and it's associated with a wide range of chronic diseases, including cancer, diabetes, cardiovascular diseases, and autoimmune disorders. There's even some evidence that the chronic inflammation associated with COPD can raise your risk for other diseases that are characterized by chronic inflammation, including heart disease.
The severity of systemic inflammation can vary from person to person, though it tends to increase during COPD exacerbations. Systemic inflammation also tends to increase as COPD gets worse (PDF link), as patients with more severe symptoms and more advanced disease tend to have more inflammatory markers than those with mild disease.
However, researchers are not exactly sure why COPD causes systemic inflammation, or how it fits into the mechanisms of the disease as a whole. It is clear, however, that systemic inflammation is closely related to COPD symptoms, and particularly to COPD exacerbations.
Research on inflammatory markers in people with COPD shows that both airway inflammation and systemic inflammation increase during COPD exacerbations. Other studies find similar links between exacerbations and systemic inflammation, including that patients with higher levels of inflammatory markers in their bloodstream have a higher risk for COPD exacerbations along with a tendency to have exacerbations that are longer and more severe.
Inhaled Steroids Versus Systemic Steroids: A Major Difference
Before we dive into the details of how different steroid medications work, it's important to discus some very important differences between inhaled and systemic corticosteroids. Both types of steroids are used in COPD treatment, but they differ significantly in why they're used and how they work in the body.
Systemic steroids come in two different forms: the most common is an oral pill that you swallow, but in some cases doctors administer systemic steroids through an injection. Both routes cause the medication to get absorbed into your bloodstream, where it circulates through all your organs and tissues, having wide-reaching (“systemic”) effects on the whole body.
Inhaled corticosteroids, on the other hand, come in an inhaler so they can be breathed directly into the lungs and airways. This allows them to act directly on the surfaces of your lung and airway tissues, which results in much more localized effects.
Inhaled corticosteroids essentially work as topical medications; they primarily affect the lung and airway tissues that they physically come into contact with. Studies show that, unlike systemic steroids, only very small amounts of inhaled steroids actually make it into the bloodstream, significantly limiting their effects on other parts of the body besides the respiratory system.
Because systemic steroids affect the whole body, they can have a lot unintended, and potentially serious, side effects. On the other hand, inhaled corticosteroids tend to be less risky and have fewer side effects (PDF link) since they are limited mainly to the lungs.
Another major difference between these two types of steroid medications is what they're used for:
Inhaled steroids are used by many COPD patients long-term as a daily maintenance treatment to prevent exacerbations. In some, rare cases, some doctors will prescribe high-dose inhaled corticosteroids (PDF link) to patients during an exacerbation if their symptoms are not too severe.
Systemic steroids, however, are used to treat existing COPD exacerbations, and help patients recover from exacerbations faster. Unlike inhaled steroids, systemic steroids can have very serious side effects with prolonged use, which is why doctors only prescribe them for short periods of time and discontinue them as soon as the exacerbation is gone.
Inhaled Steroid Medications: For Daily COPD Maintenance and Exacerbation Prevention
Inhaled corticosteroid medications are used pretty frequently in COPD treatment because of their ability to prevent COPD exacerbations. They're almost always prescribed in combination with a long-acting bronchodilator, either in a separate inhaler or in a combination steroid-bronchodilator inhaler.
However, unlike bronchodilator medications, which are broadly used by people with COPD, steroid inhalers are typically prescribed much more selectively. Usually, they're reserved for COPD patients who show a particular need for protection from exacerbations, particularly those who have had exacerbations frequently in the past.
While bronchodilators have a direct, relaxing effect on bronchial tissues, steroid inhalers work indirectly by reducing inflammation in the lungs and airways. Over time, this can help reduce a variety of symptoms associated with airway inflammation, including coughing and shortness of breath.
Steroid inhalers can also reduce airway hyper-responsiveness, a common COPD ailment in which breathing in airborne irritants (like air pollution, allergens, and even common household cleaners) can easily trigger COPD symptoms. By inhibiting inflammation, inhaled steroids can make your airways less sensitive to these and other irritating airborne particles you inevitably encounter in daily life.
However, steroid inhalers aren't routinely prescribed for symptom relief alone, partially because they are not as reliable or effective at reducing COPD symptoms as broncodilators are, and partially because of their potential for side effects. What inhaled steroid are best at—and primarily used for—is preventing COPD exacerbations, and their ability to stabilize respiratory symptoms is more like an added bonus.
Common Steroid Inhaler Medications Used to Treat COPD (brand name in parentheses)
- Flunisolide (Aerospan)
- Ciclesonide (Alvesco)
- Mometasone (Asmanex)
- Fluticasone propionate (Flovent)
- Budesonide (Pulmicort Flexhaler)
- Beclomethasone dipropionate (Qvar Redihaler)
Using Inhaled Steroids to Treat COPD
There are two main types of steroid inhalers used to treat COPD: steroid-only inhalers, and combination inhalers that contain both a steroid medication and a long-acting bronchodilator. Some patients use a nebulizer instead of an inhaler to take their steroid medications.
Which method or medication is best for you depends on a variety of factors, including whether the inhaled steroid treatment is meant to be temporary or a permanent addition to your daily treatment routine. It's also important to note that inhaled steroids can take up to several weeks to begin working, so you shouldn't expect any noticeable results right away.
The most common reason that doctors prescribe steroid inhalers to people with COPD is to reduce their risk for future exacerbations. Because of this, they're most often prescribed to “frequent exacerbators” and other patients who have a higher-than-usual risk for exacerbation,.
Steroid inhalers are also sometimes prescribed to patients who struggle more than others to keep their daily COPD symptoms under control. This includes patients with very severe disease symptoms as well as those who—for whatever reason—don't respond well enough to bronchodilators alone.
One of the main ways that doctors predict a patient's exacerbation risk—and thus their need for inhaled steroid medication—is by looking at the patient's exacerbation history. Research shows that past exacerbations are one of the strongest predictors of future exacerbations, though other factors also come into play.
One of those factors is a specific type of airway inflammation, known as eosinophilic bronchial inflammation, that is known to increase patients' risk for COPD exacerbations. Anyone with COPD can have this type of inflammation, but it's particularly common in those with a history of asthma.
The only way to confirm whether or not you have eosinophilic bronchial inflammation is to take a blood test that detects high levels of eosinophils in the bloodstream. Research shows that COPD patients with high blood eosinophil counts are more likely to see benefits (in the form of reduced exacerbations) from taking inhaled steroid medications.
For reasons that are not fully understood, some COPD patients respond better to oral steroids and inhaled steroids better than others. Because of this, your doctor might monitor you and your symptoms more closely for awhile after you begin using a steroid inhaler to ensure that the medication is having the desired effect.
Here is list summarizing the major risk factors associated with an increased risk for COPD exacerbations:
- Exacerbation History: The more exacerbations you have had in the past year, the higher your risk for exacerbations in the future.
- Exacerbation Recency: Because exacerbations tend to cluster, you're more likely to have a repeat exacerbation if you've had an exacerbation within the past two months.
- Exacerbation Severity: If you have had severe exacerbations in the past, you have a higher risk of experiencing severe exacerbations in the future.
- Disease Severity: Advanced COPD and severe COPD symptoms increase your risk for exacerbations.
- Asthma: People with asthma-COPD overlap syndrome (a diagnosis of both asthma and COPD) have a higher risk for COPD exacerbations.
How Inhaled Steroid Medications Work
We already know that the purpose of inhaled steroid medications is to reduce inflammation and reduce COPD exacerbations. In these next sections, we're going to dig just a little bit deeper to understand more about how inhaled steroids achieve their anti-inflammatory effects.
Inhaled steroids work by dampening the inflammatory response in the lungs, which is significantly elevated in people with COPD. This inflammatory response is controlled by the body's own immune system, and generally works like this:
The immune system triggers an inflammatory response in the lungs by telling the cells in the lung and airway tissues to produce inflammatory chemical signals. These chemical signals do two main things: they cause inflammatory immune cells to flock to the area and cause blood flow to the area to increase (causing swelling).
When you inhale a steroid medication, it absorbs into the cells of the same lung and airway tissues that produce those inflammatory signals. There, the medication essentially “turns off” the specific genes inside those cells that allow them to create inflammatory signals, reducing their ability to continue triggering the inflammatory response.
Inhaled steroids can also activate anti-inflammatory genes, which causes the cells to produce chemicals that directly suppress inflammation. Together, these effects help to reduce inflammation in the airways and make the the airways less sensitive to inflammation triggers (e.g. allergens, air pollution, and other respiratory irritants).
The reduced inflammation and reduced airway hyper-responsiveness both help to reduce COPD symptoms that stem (at least in part) from inflammation, including excess mucus production, coughing, and shortness of breath. This can help stabilize everyday symptoms and make the lungs less susceptible to increases in inflammation.
It's also important to note that airway inflammation tends to worsen significantly during COPD exacerbations, and reducing this inflammation (through oral steroids) can speed up exacerbation recovery time. This link could at least partially explain how inhaled steroids can prevent exacerbations; if using steroid inhalers continually keeps lung inflammation suppressed, it could prevent the sharp increases in inflammation that researchers believe are at least partially responsible for triggering COPD exacerbations.
However, it's important to note that COPD-related inflammation doesn't seem to respond to steroid medications as well as other inflammatory diseases like asthma (it still responds, but to a lesser degree). Because of this, there is some disagreement in the research literature about whether or not steroids can effectively reduce inflammation in people with COPD, especially those who don't have asthma-COPD overlap syndrome.
On the other hand, research suggests that using an inhaled corticosteroid might help COPD patients by directly increasing the effectiveness of long-acting bronchodilator medications. This would explain a phenomenon researchers have long observed—that combined steroid-bronchodilator therapy is generally more effective than either medication on its own.
Here's how researchers believe this phenomenon works: First, long-acting bronchodilators work by activating specific receptors in your cells called beta-2 receptors. Studies show that inhaled steroids can increase the total number of beta-2 receptors in your cells, which could allow long-acting bronchodilators to activate more receptors than they would otherwise be able to, amplifying their effects.
Unfortunately, researchers are still not sure exactly how inhaled corticosteroids reduce COPD symptoms and exacerbations on a fundamental level, though their anti-inflammatory and beta2-agonist effects of