Asthma

Asthma is a chronic disease that affects your airways. The airways are the tubes that carry air in and out of your lungs. If you have asthma, the inside walls of your airways are inflamed (swollen). The inflammation makes the airways very sensitive, and they tend to react strongly to things that you are allergic to or find irritating. When the airways react, they get narrower, and less air flows through to your lung tissue. This causes symptoms like wheezing (a whistling sound when you breathe), coughing, chest tightness, and trouble breathing, especially at night and in the early morning.

Asthma cannot be cured, but most people with asthma can control it so that they have few and infrequent symptoms and can live active lives.

When your asthma symptoms become worse than usual, it is called an asthma episode or attack. During an asthma attack, muscles around the airways tighten up, making the airways narrower so less air flows through. Inflammation increases, and the airways become more swollen and even narrower. Cells in the airways may also make more mucus than usual. This extra mucus also narrows the airways. These changes make it harder to breathe.

Asthma attacks are not all the same—some are worse than others. In a severe asthma attack, the airways can close so much that not enough oxygen gets to vital organs. This condition is a medical emergency. People can die from severe asthma attacks.

So, if you have asthma, you should see your doctor regularly. You will need to learn what things cause your asthma symptoms and how to avoid them. Your doctor will also prescribe medicines to keep your asthma under control.

Taking care of your asthma is an important part of your life. Controlling it means working closely with your doctor to learn what to do, staying away from things that bother your airways, taking medicines as directed by your doctor, and monitoring your asthma so that you can respond quickly to signs of an attack. By controlling your asthma every day, you can prevent serious symptoms and take part in all activities.

If your asthma is not well controlled, you are likely to have symptoms that can make you miss school or work and keep you from doing things you enjoy. Asthma is one of the leading causes of children missing school.

Symptoms

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 when you breathe.
• Chest tightness. This can feel like something is squeezing or sitting on your chest.
• Shortness of breath. Some people say they can't catch their breath, or they feel breathless or out of breath. You may feel like you can't get enough air in or out of your lungs.
• Faster breathing or noisy breathing.

Not all people have these symptoms, and symptoms may vary from one asthma attack to another. Symptoms can differ in how severe they are: Sometimes symptoms can be mildly annoying, other times they can be serious enough to make you stop what you are doing, and sometimes symptoms can be so serious that they are life threatening.

Symptoms also differ in how often they occur. Some people with asthma have symptoms only once every few months, others have symptoms every week, and still other people have symptoms every day. With proper treatment, however, most people with asthma can expect to have few or no symptoms.

Diagnosis

Some things your doctor will ask about include::

• Periods of coughing, wheezing, shortness of breath, or chest tightness that come on suddenly, occur often, or seem to happen during certain times of the year or season
• Colds that seem to "go to the chest" or take more than 10 days to get over
• Medicines you may have used to help your breathing
• Your family history of asthma and allergies
• Things that seem to cause your symptoms or make them worse

Your doctor will listen to your breathing and look for signs of asthma or allergies.

Your doctor will probably use a device called a spirometer to check how your lungs are working. This test is called spirometry. The test measures how much air you can blow out of your lungs after taking a deep breath, and how fast you can do it . The results will be lower than normal if your airways are inflamed and narrowed, or if the muscles around your airways have tightened up.

As part of the test, your doctor may give you a medicine that helps open narrowed airways to see if the medicine changes or improves your test results.

Spirometry is also used to check your asthma over time to see how you are doing.

Spirometry usually cannot be used in children younger than 5 years. If your child is younger than 5 years, the doctor may decide to try medicine for a while to see if the child's symptoms get better.

If your spirometry results are normal but you have asthma symptoms, your doctor will probably want you to have other tests to see what else could be causing your symptoms.

These include:

• Allergy testing to find out if and what allergens affect you.
• A test in which you use a peak flow meter every day for 1-2 weeks to check your breathing. A peak flow meter is a hand-held device that helps you monitor how well you are breathing.
• A test to see how your airways react to exercise.
• Tests to see if you have gastroesophageal reflux disease.
• A test to see if you have sinus disease.

Other tests, such as a chest x ray or an electrocardiogram, may be needed to find out if a foreign object or other lung diseases or heart disease could be causing your symptoms. A correct diagnosis is important because asthma is treated differently from other diseases with similar symptoms.

Depending on the results of your physical exam, medical history, and lung function tests, your doctor can determine how severe your asthma is. This is important because the severity of your asthma will determine how your asthma should be treated. One way for doctors to classify asthma severity is by considering how often you have symptoms when you are not taking any medicine or when your asthma is not well controlled.

Based on symptoms, the four levels of asthma severity are:

• Mild intermittent (comes and goes)—you have episodes of asthma symptoms twice a week or less, and you are bothered by symptoms at night twice a month or less; between episodes, however, you have no symptoms and your lung function is normal.
• Mild persistent asthma—you have asthma symptoms more than twice a week, but no more than once in a single day. You are bothered by symptoms at night more than twice a month. You may have asthma attacks that affect your activity.
• Moderate persistent asthma—you have asthma symptoms every day, and you are bothered by nighttime symptoms more than once a week. Asthma attacks may affect your activity.
• Severe persistent asthma—you have symptoms throughout the day on most days, and you are bothered by nighttime symptoms often. In severe asthma, your physical activity is likely to be limited.

Anyone with asthma can have a severe attack—even people who have intermittent or mild persistent asthma.

Causes

What Causes Asthma?

It is not clear exactly what makes the airways of people with asthma inflamed in the first place. Your inflamed airways may be due to a combination of things. We know that if other people in your family have asthma, you are more likely to develop it. New research suggests that being exposed to things like tobacco smoke, infections, and some allergens early in your life may increase your chances of developing asthma.

What Causes Asthma Symptoms and Attacks?

There are things in the environment that bring on your asthma symptoms and lead to asthma attacks. Some of the more common things include exercise, allergens, irritants, and viral infections. Some people have asthma only when they exercise or have a viral infection.

The list below gives some examples of things that can bring on asthma symptoms.

Allergens

• Animal dander (from the skin, hair, or feathers of animals)
• Dust mites (contained in house dust)
• Cockroaches
• Pollen from trees and grass
• Mold (indoor and outdoor)

Irritants

• Cigarette smoke
• Air pollution
• Cold air or changes in weather
• Strong odors from painting or cooking
• Scented products
• Strong emotional expression (including crying or laughing hard) and stress

Others

• Medicines such as aspirin and beta-blockers
• Sulfites in food (dried fruit) or beverages (wine)
• A condition called gastroesophageal reflux disease that causes heartburn and can worsen asthma symptoms, especially at night
• Irritants or allergens that you may be exposed to at your work, such as special chemicals or dusts
• Infections

This is not a complete list of all the things that can bring on asthma symptoms. People can have trouble with one or more of these. It is important for you to learn which ones are problems for you. Your doctor can help you identify which things affect your asthma and ways to avoid them.

Reference:

National Heart, Lung and Blood Institute, USA.