Asthma: Symptoms, Causes, Diagnosis and Treatment
Asthma is a chronic disease characterized by inflammation of the airways in the lungs. The airways are tubes that carry air in and out of your lungs.
People with asthma have sensitive airways that become inflamed when they are exposed to triggers. When the airways become inflamed, it will become narrowed and clogged with mucus. This makes it harder for air to pass through and leads to asthma symptoms.
What are the Symptoms of Asthma?
Symptoms of asthma vary depending on how severe or intense the condition is. Some people have only mild symptoms that occur infrequently, while others have more severe symptoms that happen frequently.
Severe asthma attacks can be life-threatening if treatment is not sought immediately. So, it is important to recognize and treat even mild asthma symptoms to help you prevent the onset of severe asthma attack.
Early signs and symptoms of Asthma
You may experience early warning signs before the start of an asthma episode. By recognizing these clues that occur before actual asthma symptoms, early treatment can be started.
These signs can be different for each person – some early warning signs may be noticed only by the individual, while other early warning signs are more likely to be noticed by other persons. These early warning signs include:
- Coughing, especially at night
- Changes in breathing
- Runny or stuffy nose
- Feeling tired
- Trouble sleeping
- Dark circles under eyes
Symptoms of severe Asthma
If early warning signs and symptoms are not recognized and treated, the asthma episode can progress and symptoms may become worse over time or are suddenly very severe. Symptoms of severe asthma include:
- A cough that won’t go away
- Severe wheezing
- Tightness in the chest
- Shortness of breath
- Difficulty talking
- A fast heartbeat
- Blue lips or fingernails
- Peak flow numbers in the danger zone (usually below 50% of personal best)
Severe asthma symptoms are a life-threatening emergency. If any of these severe asthma symptoms occur, seek emergency medical treatment right away.
What Causes Asthma?
The exact cause of asthma is not known, but it is often the result of a strong immune-system response to an allergen, such as pollen, dust mites, and ragweed.
Normally, the body’s immune system helps to fight infections, but when someone breathes in an allergen, the immune system in the airways may react by creating inflammation.
Inflammation makes your airways swell and narrow and possibly produce extra mucus, which make it harder to breathe. Moreover, the muscles that wrap around your airways may also tighten, making breathing even harder. When that happens, it’s called an asthma attack.
Risk factors for Asthma
Many studies have shown that a number of factors are associated with increased risk of developing asthma. They include:
There is evidence to suggest that genetics play an important role in causing asthma. Studies have shown that if you have family members with asthma, then you are more likely to suffer from asthma too. However, the genes that are involved are not clearly identified. It is believed that the genes linked to asthma involve the lungs and the immune system.
One study suggests that asthma is more common in overweight adults and children. Although the reasons are unclear, some experts point to low-grade inflammation in the body that occurs with extra weight. Obese patients often use more medications, suffer worse symptoms and are less able to control their asthma than patients in a healthy weight range.
There’s evidence that cigarette smoking among adolescents increases the risk of developing asthma. Those who are exposed to secondhand smoke are also more likely to have asthma, according to the American Lung Association.
Most people who have asthma have the allergic type. This means that your asthma is triggered by exposure to certain allergens. Examples are:
- Dust mites
- Pet dander
- Certain foods, such as eggs, milk, soy, peanuts, shellfish, and wheat.
Young children and those with a history of respiratory infections have been shown to have an increased risk of asthma. This because their tiny airways are filled easily with mucus when they have respiratory infections. This can lead to the wheezing sound that commonly signals asthma. About half of children with asthma develop symptoms by age two, and about 80% will have symptoms by age five.
How is Asthma Diagnosed?
To diagnose asthma, your doctor will ask you about your symptoms, your medical history as well as your family health history. The doctor will also carry out a physical examination and may conduct some other tests.
During a physical exam for asthma, your doctor will look at your eyes, nose, throat, chest, and skin. The exam includes checking your breathing, listening to your lungs, and examining your skin for allergic reactions.
Lung function tests
These tests measure how well your lungs work. They are often done before and after inhaling a medicine known as a bronchodilator, which opens your airways. If your lung function improves a lot with the use of a bronchodilator, you probably have asthma. Some of the most common tests used to diagnose asthma include:
- Peak flow. This measures how hard you can breathe out. Lower than usual peak flow readings are a sign that your lungs may not be working well and that your asthma may be getting worse. Your doctor will give you instructions on how to track and deal with low peak flow readings.
- Spirometry. This test estimates the narrowing of your bronchial tubes by checking how much air you can exhale after a deep breath and how fast you can breathe out.
- Challenge tests. These tests might be performed if your symptoms and spirometry test do not clearly show you have asthma. There are two types of challenge tests: methacholine and mannitol.
During these tests, you will inhale increasing amounts of either methacholine or mannitol before and after lung function tests. These agents when inhaled can cause the airways to spasm and narrow if asthma is present. A bronchodilator is always administered at the end of the test to reverse the effects of these agents.
- Exhaled nitric oxide test. Your doctor may have you breathe into a tube connected to a machine that measures the amount if nitric oxide in your breath. High levels of nitric oxide in your body is a sign that you may have asthma.
A chest X-ray is a test that uses low doses of radiation to create an image of a person’s chest.
Although it isn’t an asthma test, your doctor can use it to see if asthma is likely to be causing your symptoms. A chest X-ray can also make sure you don’t have pneumonia or lung cancer, particularly in smokers.
How is Asthma Treated?
Currently, there is no cure for asthma but treatment can help manage the symptoms so you’re able to live a normal, healthy life.
Prevention and long-term control are key to stopping asthma attacks before they start. Treatment usually involves learning to recognize your triggers, taking steps to avoid triggers and keeping your symptoms under control. In case of an asthma flare-up, you may need to use a quick-relief inhaler.
Your health care provider will develop an individualized plan to help identify the best medications and procedures for controlling your condition. Generally, there are two types of medication used in the treatment of asthma: quick-relief medications and long-term control medications.
Quick relief medications, also called rescue therapy, are used to quickly ease the symptoms of asthma. They work by relaxing the tightened muscles of your airways so that the airways can open and allow more air to pass through. Some common quick relief medications are:
- Short-acting beta-agonists (SABAs). These medicines are the first choice for quick relief of asthma symptoms. These quick-relief bronchodilators act within minutes to rapidly ease symptoms during an asthma attack. They include albuterol (ProAir HFA, Proventil HFA, Ventolin HFA), epinephrine (Asthmanefrin, Primatene Mist), and levalbuterol (Xopenex HFA).
Short-acting beta agonists can be taken using a hand-held inhaler or a nebulizer, a machine that converts asthma medications to a fine mist. They’re inhaled through a face mask or mouthpiece.
- Anticholinergics. Like SABAs, anticholinergics act quickly to immediately relax your airways, making it easier to breathe. While not as fast acting as short-acting beta agonists, they begin to work within 15 minutes and their effects can last several hours.
Anticholinergics are usually used for severe asthma attacks to help relieve the symptoms for a longer period of time.
If you have exercise-induced asthma, your allergist may recommend that you use these drugs before exercise or other strenuous physical activity.
Tell your doctor if you are using quick-relief medicine twice a week or more to control your asthma symptoms. Because your asthma may not be under control and your doctor may need to change your dose of daily control drugs.
Long-term control medications
Long-term control medications are medications that should be taken daily to control asthma symptoms and to prevent future asthma attacks. There are several types of long-term control medications:
- Corticosteroids. These drugs are the most effective and commonly used long-term control medications for asthma. They help reduce swelling and tightening in your airways. They also reduce mucus in the lungs. You may need to use these medications for several weeks to months before you get their maximum benefit.
These medications include fluticasone propionate (Flovent HFA, Flovent Diskus), budesonide (Pulmicort Flexhaler, Pulmicort Respules), ciclesonide (Alvesco), beclomethasone (Qvar Redihaler), and fluticasone furoate (Arnuity Ellipta).
- Long-acting beta agonists (LABAs). These bronchodilator medications are used for the long-term prevention and control of asthma symptoms. They work by relaxing the smooth muscles around the airways, allowing for better airflow.
LABAs are most often used as a combination medicine along with an inhaled corticosteroid. These medicines include salmeterol, formoterol, and vilanterol.
- Biologics. They are shots or infusions that given every few weeks. These medications work by targeting a cell or protein in your body to prevent airway inflammation.
Biologic drugs are the most advanced treatments available but are more expensive, so they are usually only prescribed if other medications don’t work.
- Leukotriene modifiers. These medicines relax smooth muscles and reduce swelling inside the airways. They can help prevent symptoms for up to 24 hours and are taken in pill or liquid form. These medications include montelukast (Singular), zafirlukast (Accolate), and zileuton (Zyflo).
- Theophylline. It is another long-term control medication that helps keep the airways open by relaxing the muscles around the airways. It comes as a capsule, tablet, or syrup. It’s not used as often as other asthma medications and requires regular blood tests to make sure you’re getting the correct dose.