Coughing, wheezing, chest tightness, and difficulty breathing can be indicative of many chest conditions. Of those conditions, bronchial asthma (asthma) and bronchitis are among the most common, and the most commonly confused. Though they have similar symptoms, they differ in their causes and treatment. So, what’s the difference between bronchitis and asthma? First, let’s gain a basic understanding of what they are.
Understanding asthma and bronchitis
What is bronchial asthma? Asthma is a chronic inflammatory disease affecting the bronchus, or airway of the respiratory tract leading to the lungs. The presence of asthma is determined by a combination of genetic and environmental stimuli. However, the exact cause of asthma is not known with certainty.
Bronchitis is a condition in which the bronchioles are inflamed, usually from viral infection, environmental irritants, smoking, and occasionally bacterial infection. Bronchitis can be acute, or short-lived, or it can be chronic and last for years.
Causes of Asthma
Bad news if you have a parent with asthma: those with asthma in their direct family history have a 300-600% greater chance of developing asthma than those without asthma in their bloodline. Researchers have found at least 30 phenotypic variations in DNA that contribute towards the likelihood of asthma, but our understanding of asthma heredity and how it affects the development of airway constriction is still incomplete. Along with asthma specific genes, links have been found between genetic predisposition towards atopy (standard allergies) and asthma. So if you or your parents suffer from allergic symptoms such as hay fever, eczema, or hives, there is a much higher likelihood that you will develop asthma than those who do not.
Adults can develop asthma with women being more likely to develop adult asthma than men. This is usually attributed to women having more frequent and severe hormonal changes than men in adulthood. Two big hormonal changes are:
Pregnancy - Those who experience asthma symptoms during pregnancy without prior history of the condition should consult a doctor immediately. Uncontrolled asthma can lead to high blood pressure in the mother, which can in turn lead to premature birth and slower fetal development.
Menopause - Post-menopausal women who take estrogen supplements over a prolonged period are more likely to develop asthma than those who don’t.
Can you develop asthma without an asthmatic family history? Yes. Asthma can also occur in those who aren’t genetically predisposed. In adults, environmental factors are a more common cause of asthma than in children. Common factors include air pollution, dust and dust mites, pet dander, and even cold air or wind. Areas with the highest levels of pollution see the highest numbers of asthma. It is estimated that over half of all asthma cases in the US occur in areas with substandard air quality. Microbes, allergens, chemicals, and other commonly occurring indoor irritants play a role in the development of asthma and often trigger asthma attacks. Common irritants include:
Pet Dander - Animal allergies, to cats in particular, are very commonly associated with adult onset asthma.
Chemicals - Phthalate esters, formaldehyde, and cleaning products.
Occupational and behavioral stimuli such as chemical irritants in the workplace, tobacco smoking, exercise, and certain medications can also be factors. Alcohol can be a trigger for many people throughout the world, most commonly in those of Asian descent. Alcohol can also worsen symptoms in nearly 33% of asthmatic individuals. Medical triggers can include medications like NSAIDs and beta-blockers as well as conditions like:
Anxiety and Mood disorders
COPD (Chronic obstructive pulmonary disorder)
Obstructive Sleep Apnea
Occupational hazards can be a key factor. Factory workers, painters, construction workers, and many other blue collar jobs report higher numbers of asthmatic sufferers. Anywhere from 5-25% of asthma cases reported annually are caused by occupational factors. The risk of asthma is greatly increased in settings with:
Wood and sawdust
Flour (bakeries/food processing)
Bronchitis is usually classified as either acute or chronic bronchitis, depending on the duration of its symptoms. Acute and chronic bronchitis differ in their risk factors and causes.
Acute Bronchitis Causes
Around 9 out of 10 cases of acute bronchitis are caused by viral infection. As such, it is usually contagious, and can be spread via direct contact or aspirated water droplets. While viral infection is the main culprit, the odds of contracting acute bronchitis increase with exposure to environmental factors such as smoke, dust, pollen, and air pollution. A small percentage of acute bronchitis cases develop solely through bacterial infection or heavy air pollution.
Chronic Bronchitis Causes
The vast majority of chronic bronchitis cases are onset by cigarette smoking. Besides smoking, hazardous occupations such as farming, mining, chemical processing, metallurgy, or any large-scale industrial work increases the odds of contracting chronic bronchitis. These causes overlap with those of asthma, and are some of the primary reasons that the two diseases are misdiagnosed, especially when self-diagnosed.
While asthma and bronchitis are similarly symptomatic, there are a few key differences.
Asthma symptoms can range from mild discomfort to life-threatening acute attacks that require immediate professional attention. These symptoms include: wheezing, coughing, chest tightness, and shortness of breath.
Cough-variant asthma is a form of asthma in which the primary symptom is a dry, non-productive cough, usually accompanied by chest tightness and wheezing. This is probably the form of asthma most easily confused with bronchitis. While some affected by asthma cough mucus, an asthma cough is usually nonproductive, which is the biggest indicator in diagnosing between the two.
Along with the immediate symptoms, having asthma may lead to acid reflux disease and rhinosinusitis, an infection of the nasal-adjacent sinus cavities. Asthma may also result in obstructive sleep apnea, which can lead to countless health issues. Those with asthma are more likely to have issues with anxiety and mood disorders, though it is still unclear to doctors which affects the other.
Like with asthma, individuals with bronchitis may experience wheezing, coughing, chest tightness, and difficulty breathing. This is usually mild to moderate in severity, with nothing resembling a major asthma attack. Bronchitis also usually causes the production of mucus in the bronchioles, which can be white, green, yellowish, and occasionally contain blood. Due to the likely viral cause of many bronchitis cases, the sufferer may experience a fever and chills, along with whatever symptoms accompany the particular infection at hand. Individuals with bronchitis, especially chronic bronchitis, may also experience fatigue due to difficulty sleeping with a persistent cough. Lack of uninterrupted sleep over a long period of time can lead to cognitive issues, lessened hand-eye coordination, increased likelihood of other diseases, and a weakened immune system, among others.
Asthma tests usually include some form of spirometry test, in which the patient blows into a spirometer and the results are analyzed. Spirometry comes from the roots “spiro” (breath) and “metre” (measure), so spirometry is the measurement of breath. The most common test using spirometry is the FEV-1 or the forced expiration by volume for 1 second. Healthy lungs should be able to output anywhere from 80-120% of their expected expiration (based on variables like age, sex, race, etc.). For those with asthma, that percentage will be far lower. There are many variations of spirometry testing and other ways to diagnose asthma.
Bronchitis is usually diagnosed via a combination stethoscope examination and symptomatic observation. A doctor may test the patient’s mucus in order to figure out the root of the infection in the case of acute bronchitis. At times, a physician may request that the patient takes a chest x-ray in order to test for pneumonia or other more severe chest conditions that have similar symptoms.
Since it cannot be cured, asthma must be managed, which means the asthmatic patient must always be monitoring their condition to gauge therapeutic response and asthmatic control. This also means that the patient must responsibly avoid potential triggers by planning around them or removing themselves from the danger zone. Coming up with an asthma management plan is something that your physician can help you with.
Most asthma medications are administered via metered-dose inhalers. If the patient does not respond adequately to these inhalers, some asthma medications come in pill form as well. In extreme cases, direct use of oxygen may be necessary.
Since the cause of most acute bronchitis cases is viral, there is little the patient can do but rest and avoid irritants. Doctors may prescribe antibiotics if they believe the root to be bacterial. However, the over-prescription of antibiotics as a safeguard has become a major problem, as they end up killing many of the helpful bacteria in the body and can lead to more antibiotic resistant strains of diseases. As such, there has been a push for doctors to stop prescribing antibiotics unless there is strong evidence that the root of the bronchitis is bacterial.
Other than that, over-the-counter cough suppressants and expectorants may reduce symptoms and allow for easier sleep.
While asthma and bronchitis may seem indistinguishable, there are ways to tell the difference. If you think you have symptoms of asthma, call or book online with PlushCare to set up a phone appointment with a top U.S. doctor today.