Asthma

Introduction of Asthma:

Asthma (AZ-ma) is a chronic (long-term) lung disease that inflames and narrows the airways. Asthma causes recurring periods of wheezing (a whistling sound when you breathe), chest tightness, shortness of breath, and coughing. The coughing often occurs at night or early in the morning.

Asthma

Causes of Asthma:

The exact cause of asthma isn't known. Researchers think a combination of factors (family genes and certain environmental exposures) interact to cause asthma to develop, most often early in life. These factors include:

• An inherited tendency to develop allergies, called atopy (AT-o-pe)
• Parents who have asthma
• Certain respiratory infections during childhood
• Contact with some airborne allergens or exposure to some viral infections in infancy or in early childhood when the immune system is developing

If asthma or atopy runs in your family, exposure to airborne allergens (for example, house dust mites, cockroaches, and possibly cat or dog dander) and irritants (for example, tobacco smoke) may make your airways more reactive to substances in the air you breathe.
Different factors may be more likely to cause asthma in some people than in others. Researchers continue to explore what causes asthma.

Signs and Symptoms of Asthma:
Common asthma symptoms include:

• Coughing. Coughing from asthma is often worse at night or early in the morning, making it hard to sleep.
• Wheezing. Wheezing is a whistling or squeaky sound that occurs when you breathe.
• Chest tightness. This may feel like something is squeezing or sitting on your chest.
• Shortness of breath. Some people who have asthma say they can't catch their breath or they feel out of breath. You may feel like you can't get air out of your lungs.

Not all people who have asthma have these symptoms. Likewise, having these symptoms doesn't always mean that you have asthma. A lung function test, done along with a medical history (including type and frequency of your symptoms) and physical exam, is the best way to diagnose asthma for certain.
The types of asthma symptoms you have, how often they occur, and how severe they are may vary over time. Sometimes your symptoms may just annoy you. Other times they may be troublesome enough to limit your daily routine.
Severe symptoms can threaten your life. It's vital to treat symptoms when you first notice them so they don't become severe.
With proper treatment, most people who have asthma can expect to have few, if any, symptoms either during the day or at night.

Factor Causes Asthma Symptoms:

A number of things can bring about or worsen asthma symptoms. Your doctor will help you find out which things (sometimes called triggers) may cause your asthma to flare up if you come in contact with them. Triggers may include:

• Allergens found in dust, animal fur, cockroaches, mold, and pollens from trees, grasses, and flowers
• Irritants such as cigarette smoke, air pollution, chemicals or dust in the workplace, compounds in home décor products, and sprays (such as hairspray)
• Certain medicines such as aspirin or other nonsteroidal anti-inflammatory drugs and nonselective beta-blockers
• Sulfites in foods and drinks
• Viral upper respiratory infections such as colds
• Exercise (physical activity)

Other health conditions—such as runny nose, sinus infections, reflux disease, psychological stress, and sleep apnea—can make asthma more difficult to manage. These conditions need treatment as part of an overall asthma care plan.
Asthma is different for each person. Some of the factors listed may not affect you. Other factors that do affect you may not be on the list. Talk to your doctor about the things that seem to make your asthma worse.

Diagnosis of Asthma:

Your primary care doctor will diagnose asthma based on your medical history, a physical exam, and results from tests. He or she also will figure out what your level of asthma severity is—that is, whether it's intermittent, mild, moderate, or severe. Your severity level will determine what treatment you will start on.

You may need to see an asthma specialist if:

• You need special tests to be sure you have asthma
• You've had a life-threatening asthma attack
• You need more than one kind of medicine or higher doses of medicine to control your asthma, or if you have overall difficulty getting your asthma well controlled
• You're thinking about getting allergy treatments

Medical History

Your doctor may ask about your family history of asthma and allergies. He or she also may ask whether you have asthma symptoms, and when and how often they occur. Let your doctor know if your symptoms seem to happen only during certain times of the year or in certain places, or if they get worse at night.

Your doctor also may want to know what factors seem to set off your symptoms or worsen them. For more information on what causes asthma symptoms to occur, see "What Are the Signs and Symptoms of Asthma?"

Your doctor may ask you about related health conditions that can interfere with asthma management. These conditions include a runny nose, sinus infections, reflux disease, psychological stress, and sleep apnea.

Physical Exam

Your doctor will listen to your breathing and look for signs of asthma or allergies. These signs include wheezing, a runny nose or swollen nasal passages, and allergic skin conditions such as eczema.

Keep in mind that you can still have asthma even if you don't have these signs on the day that your doctor examines you.

Diagnostic Tests
 

Lung Function Test

Your doctor will use a test called spirometry (spi-ROM-eh-tre) to check how your lungs are working. This test measures how much air you can breathe in and out. It also measures how fast you can blow air out. Your doctor also may give you medicines and then test you again to see whether the results have improved.
If the starting results are lower than normal and improve with the medicine, and if your medical history shows a pattern of asthma symptoms, your diagnosis will likely be asthma.

Other Tests
Your doctor may order other tests if he or she needs more information to make a diagnosis. Other tests may include:

• Allergy testing to find out which allergens affect you, if any.
• A test to measure how sensitive your airways are. This is called a bronchoprovocation test. Using spirometry, this test repeatedly measures your lung function during physical activity or after you receive increasing doses of cold air or a special chemical to breathe in.
• A test to show whether you have another disease with the same symptoms as asthma, such as reflux disease, vocal cord dysfunction, or sleep apnea.
• A chest x ray or an EKG (electrocardiogram). These tests will help find out whether a foreign object or other disease may be causing your symptoms.

Diagnosing Asthma in Young Children:

Most children who have asthma develop their first symptoms before 5 years of age. However, asthma in young children (aged 0 to 5 years) can be hard to diagnose. Sometimes it can be difficult to tell whether a child has asthma or another childhood condition because the symptoms of both conditions can be similar.

Also, many young children who have wheezing episodes when they get colds or respiratory infections don't go on to have asthma after they're 6 years old. These symptoms may be due to the fact that infants have smaller airways that can narrow even further when they get a cold or respiratory infection. The airways grow as a child grows older, so wheezing no longer occurs when the child gets a cold.

A young child who has frequent wheezing with colds or respiratory infections is more likely to have asthma if:

• One or both parents have asthma
• The child has signs of allergies, including the allergic skin condition eczema
• The child has allergic reactions to pollens or other airborne allergens
• The child wheezes even when he or she doesn't have a cold or other infection

A lung function test along with a medical history and physical exam is the most certain way to diagnose asthma. However, this test is hard to do in children younger than 5 years. Thus, doctors must rely on children's medical histories, signs and symptoms, and physical exams to make a diagnosis. Doctors also may use a 4 to 6 week trial of asthma medicines to see how well a child responds.

Asthma Treatment and Control:
Asthma is a long-term disease that can't be cured. The goal of asthma treatment is to control the disease. Good asthma control will:

• Prevent chronic and troublesome symptoms such as coughing and shortness of breath
• Reduce your need of quick-relief medicines (see below)
• Help you maintain good lung function
• Let you maintain your normal activity levels and sleep through the night
• Prevent asthma attacks that could result in your going to the emergency room or being admitted to the hospital for treatment

Medicines

Your doctor will consider many things when deciding which asthma medicines are best for you. Doctors usually use a stepwise approach to prescribing medicines. Your doctor will check to see how well a medicine works for you; he or she will make changes in the dose or medicine, as needed.

Asthma medicines can be taken in pill form, but most are taken using a device called an inhaler. An inhaler allows the medicine to go right to your lungs.

Not all inhalers are used the same way. Ask your doctor and other clinicians on your health care team to show you the right way to use your inhaler. Ask them to review the way you use your inhaler at every visit.

Long-Term Control Medicines

Most people who have asthma need to take long-term control medicines daily to help prevent symptoms. The most effective long-term medicines reduce airway inflammation.

These medicines are taken over the long term to prevent symptoms from starting. They don't give you quick relief from symptoms.

Inhaled corticosteroids. Inhaled corticosteroids are the preferred medicines for long-term control of asthma. These medicines are the most effective long-term control medicine to relieve airway inflammation and swelling that makes the airways sensitive to certain substances that are breathed in.

Reducing inflammation helps prevent the chain reaction that causes asthma symptoms. Most people who take these medicines daily find they greatly reduce how severe symptoms are and how often they occur.

Inhaled corticosteroids are generally safe when taken as prescribed. They're very different from the illegal anabolic steroids taken by some athletes. Inhaled corticosteroids aren't habit-forming, even if you take them every day for many years.

But, like many other medicines, inhaled corticosteroids can have side effects. Most doctors agree that the benefits of taking inhaled corticosteroids and preventing asthma attacks far outweigh the risks of side effects.

One common side effect from inhaled corticosteroids is a mouth infection called thrush. You can use a spacer or holding chamber to avoid thrush. A spacer or holding chamber is attached to your inhaler when taking medicine to keep the medicine from landing in your mouth or on the back of your throat.

Work with your health care team if you have any questions about how to use a spacer or holding chamber. Rinsing your mouth out with water after taking inhaled corticosteroids also can lower your risk of thrush.

If you have severe asthma, you may have to take corticosteroid pills or liquid for short periods to get your asthma under control. If taken for long periods, these medicines raise your risk for cataracts and osteoporosis (OS-te-o-po-RO-sis). A cataract is the clouding of the lens in your eye. Osteoporosis is a disorder that makes your bones weak and more likely to break.

Your doctor may have you add another long-term control asthma medicine to lower your dose of corticosteroids. Or, your doctor may suggest you take calcium and vitamin D pills to protect your bones.

Other long-term control medicines. Other long-term control medicines include:

• Inhaled long-acting beta₂-agonists. These medicines open the airways and may be added to low-dose inhaled corticosteroids to improve asthma control. An inhaled long-acting beta₂-agonist shouldn't be used alone.
• Leukotriene modifiers. These medicines are taken by mouth. They help block the chain reaction that increases inflammation in your airways.
• Cromolyn and nedocromil. These inhaled medicines also help prevent inflammation and can be used to treat asthma of mild severity.
• Theophylline. This medicine is taken by mouth and helps open the airways.

If your doctor prescribes a long-term control medicine, take it every day to control your asthma. Your asthma symptoms will likely return or get worse if you stop taking your medicine.

Long-term control medicines can have side effects. Talk to your doctor about these side effects and ways to monitor or avoid them.

Quick-Relief Medicines 

All people who have asthma need a quick-relief medicine to help relieve asthma symptoms that may flare up. Inhaled short-acting beta₂-agonists are the first choice for quick relief.

These medicines act quickly to relax tight muscles around your airways when you're having a flareup. This allows the airways to open up so air can flow through them.

You should take your quick-relief medicine when you first notice your asthma symptoms. If you use this medicine more than 2 days a week, talk with your doctor about how well controlled your asthma is. You may need to make changes in your asthma action plan.

Carry your quick-relief inhaler with you at all times in case you need it. If your child has asthma, make sure that anyone caring for him or her and the child's school has the child's quick-relief medicines. They should understand when and how to use them and when to seek medical care for your child.

You shouldn't use quick-relief medicines in place of prescribed long-term control medicines. Quick-relief medicines don't reduce inflammation.

Can Asthma Be Prevented?
Currently, there isn't a way to prevent asthma from starting in the first place. However, you can take steps to control the disease and prevent its symptoms.

• Learn about your asthma and how to control it.
• Follow your written asthma action plan. (See the National Heart, Lung, and Blood Institute's Asthma Action Plan as a sample.)
• Use medicines as your doctor directs.
• Identify and avoid things that make your asthma worse (as much as you can).
• Keep track of your asthma symptoms and level of control.
• Get regular checkups for your asthma.