Asthma

Definition
Asthma is a condition in which your airways narrow and swell and produce extra mucus. This can make breathing difficult and trigger coughing, wheezing and shortness of breath.
For some people, asthma is a minor nuisance. For others, it can be a major problem that interferes with daily activities and may lead to a life-threatening asthma attack.
Asthma can't be cured, but itssymptoms can be controlled. Because asthma often changes over time, it's important that you work with your doctor to track your signs and symptoms and adjust treatment as needed.
























Symptoms


Asthma symptoms range from minor to severe and vary from person to person. You may have infrequent asthma attacks, have symptoms only at certain times — such as when exercising — or have symptoms all the time.

Asthma signs and symptoms include:

Shortness of breath 

Chest tightness or pain
Trouble sleeping caused by shortness of breath, coughing or wheezing
A whistling or wheezing sound when exhaling (wheezing is a common sign of asthma in children)
Coughing or wheezing attacks that are worsened by a respiratory virus, such as a cold or the flu

Signs that your asthma is probably worsening include:

Asthma signs and symptoms that are more frequent and bothersome
Increasing difficulty breathing (measurable with a peak flow meter, a device used to check how well your lungs are working)
The need to use a quick-relief inhaler more often


For some people, asthma symptoms flare up in certain situations:
Exercise-induced asthma, which may be worse when the air is cold and dry
Occupational asthma, triggered by workplace irritants such as chemical fumes, gases or dust
Allergy-induced asthma, triggered by particular allergens, such as pet dander, cockroaches or pollen
When to see a doctor
Seek emergency treatment


Severe asthma attacks can be life-threatening. Work with your doctor ahead of time to determine what to do when your signs and symptoms worsen — and when you need emergency treatment. Signs of an asthma emergency include:
Rapid worsening of shortness of breath or wheezing
No improvement even after using a quick-relief inhaler, such as albuterol
Shortness of breath when you are doing minimal physical activity
Contact your doctor


See your doctor: 

If you think you have asthma. If you have frequent coughing or wheezing that lasts more than a few days or any other signs or symptoms of asthma, see your doctor. Treating asthma early may prevent long-term lung damage and help keep the condition from worsening over time.
To monitor your asthma after diagnosis. If you know you have asthma, work with your doctor to keep it under control. Good long-term control helps you feel better on a daily basis and can prevent a life-threatening asthma attack.
If your asthma symptoms get worse. Contact your doctor right away if your medication doesn't seem to ease your symptoms or if you need to use your quick-relief inhaler more often. Don't try to solve the problem by taking more medication without consulting your doctor. Overusing asthma medication can cause side effects and may make your asthma worse.
To review your treatment. Asthma often changes over time. Meet with your doctor on a regular basis to discuss your symptoms and make any needed treatment adjustments.



Causes


It isn't clear why some people get asthma and others don't, but it's probably due to a combination of environmental and genetic (inherited) factors.
Asthma triggers

Exposure to various substances that trigger allergies (allergens) and irritants can trigger signs and symptoms of asthma. Asthma triggers are different from person to person and can include:
Airborne allergens, such as pollen, animal dander, mold, cockroaches and dust mites
Respiratory infections, such as the common cold
Physical activity (exercise-induced asthma)
Cold air
Air pollutants and irritants, such as smoke
Certain medications, including beta blockers, aspirin, ibuprofen (Advil, Motrin IB, others) and naproxen (Aleve)
Strong emotions and stress
Sulfites and preservatives added to some types of foods and beverages, including shrimp, dried fruit, processed potatoes,beer and wine
Gastroesophageal reflux disease (GERD), a condition in which stomach acids back up into your throat
Menstrual cycle in some women


Risk Factors


A number of factors are thought to increase your chances of developing asthma. These include:
Having a blood relative (such as a parent or sibling) with asthma
Having another allergic condition, such as atopic dermatitis or allergic rhinitis (hay fever)
Being overweight
Being a smoker
Exposure to secondhand smoke
Having a mother who smoked while pregnant
Exposure to exhaust fumes or other types of pollution
Exposure to occupational triggers, such as chemicals used in farming, hairdressing and manufacturing


Exposure to allergens, exposure to certain germs or parasites, and having some types of bacterial or viral infections also may be risk factors. However, more research is needed to determine what role they may play in developing asthma.


Complications


Asthma complications include:
Symptoms that interfere with sleep, work or recreational activities
Sick days from work or school during asthma flare-ups
Permanent narrowing of the bronchial tubes (airway remodeling) that affects how well you can breathe
Emergency room visits and hospitalizations for severe asthma attacks
Side effects from long-term use of some medications used to stabilize severe asthma


Proper treatment makes a big difference in preventing both short-term and long-term complications caused by asthma.




Test and diagnosis
Physical exam

To rule out other possible conditions — such as a respiratory infection or chronic obstructive pulmonary disease (COPD) — your doctor will do a physical exam and ask you questions about your signs andsymptoms and about any other health problems.
Tests to measure lung function


You may also be given lung (pulmonary) function tests to determine how much air moves in and out as you breathe. These tests may include:
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.
Peak flow. A peak flow meter is a simple device that measures how hard you can breathe out. Lower than usual peak flow readings are a sign your lungs may not be working as 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.


Lung function tests often are done before and after taking a bronchodilator (brong-koh-DIE-lay-tur), such as albuterol, to open your airways. If your lung function improves with use of a bronchodilator, it's likely you have asthma.
Additional tests


Other tests to diagnose asthma include:
Methacholine challenge. Methacholine is a known asthma trigger that, when inhaled, will cause mild constriction of your airways. If you react to the methacholine, you likely have asthma. This test may be used even if your initial lung function test is normal.
Nitric oxide test. This test, though not widely available, measures the amount of the gas, nitric oxide, that you have in your breath. When your airways are inflamed — a sign of asthma — you may have higher than normal nitric oxide levels.
Imaging tests. A chest X-ray and high-resolution computerized tomography (CT) scan of your lungs and nose cavities (sinuses) can identify any structural abnormalities or diseases (such as infection) that can cause or aggravate breathing problems.
Allergy testing. This can be performed by skin test or blood test. Allergy tests can identify allergy to pets, dust, mold and pollen. If important allergy triggers are identified, this can lead to a recommendation for allergen immunotherapy.
Sputum eosinophils. This test looks for certain white blood cells (eosinophils) in the mixture of saliva and mucus (sputum) you discharge during coughing. Eosinophils are present when symptoms develop and become visible when stained with a rose-colored dye (eosin).
Provocative testing for exercise and cold-induced asthma.In these tests, your doctor measures your airway obstruction before and after you perform vigorous physical activity or take several breaths of cold air.
How asthma is classified


To classify your asthma severity, your doctor considers your answers to questions about symptoms (such as how often you have asthma attacks and how bad they are), along with the results of your physical exam and diagnostic tests.


Determining your asthma severity helps your doctor choose the best treatment. Asthma severity often changes over time, requiring treatment adjustments.


Lifestyle and home remedies


Although many people with asthma rely on medications to prevent and relieve symptoms, you can do several things on your own to maintain your health and lessen the possibility of asthma attacks.
Avoid your triggers

Taking steps to reduce your exposure to things that trigger asthma symptoms is a key part of asthma control. It may help to:
Use your air conditioner. Air conditioning reduces the amount of airborne pollen from trees, grasses and weeds that finds its way indoors. Air conditioning also lowers indoor humidity and can reduce your exposure to dust mites. If you don't have air conditioning, try to keep your windows closed during pollen season.
Decontaminate your decor. Minimize dust that may worsen nighttime symptoms by replacing certain items in your bedroom. For example, encase pillows, mattresses and box springs in dustproof covers. Remove carpeting and install hardwood orlinoleum flooring. Use washable curtains and blinds.
Maintain optimal humidity. If you live in a damp climate, talk to your doctor about using a dehumidifier.
Prevent mold spores. Clean damp areas in the bath, kitchen and around the house to keep mold spores from developing. Get rid of moldy leaves or damp firewood in the yard.
Reduce pet dander. If you're allergic to dander, avoid pets with fur or feathers. Having pets regularly bathed or groomed also may reduce the amount of dander in your surroundings.
Clean regularly. Clean your home at least once a week. If you're likely to stir up dust, wear a mask or have someone else do the cleaning.
Cover your nose and mouth if it's cold out. If your asthma is worsened by cold or dry air, wearing a face mask can help.
Stay healthy


Taking care of yourself and treating other conditions linked to asthma will help keep your symptoms under control. For example:
Get regular exercise. Having asthma doesn't mean you have to be less active. Treatment can prevent asthma attacks and control symptoms during activity. Regular exercise can strengthen your heart and lungs, which helps relieve asthma symptoms. If you exercise in cold temperatures, wear a face mask to warm the air you breathe.
Maintain a healthy weight. Being overweight can worsen asthma symptoms, and it puts you at higher risk of other health problems.
Eat fruits and vegetables. Eating plenty of fruits and vegetables may increase lung function and reduce asthma symptoms. These foods are rich in protective nutrients (antioxidants) that boost the immune system.
Control heartburn and gastroesophageal reflux disease (GERD). It's possible that the acid reflux that causes heartburn may damage lung airways and worsen asthma symptoms. If you have frequent or constant heartburn, talk to your doctor about treatment options. You may need treatment for GERD before your asthma symptoms improve.


Preventions


While there's no way to prevent asthma, by working together, you and your doctor can design a step-by-step plan for living with your condition and preventing asthma attacks.
Follow your asthma action plan. With your doctor and health care team, write a detailed plan for taking medications and managing an asthma attack. Then be sure to follow your plan. Asthma is an ongoing condition that needs regular monitoring and treatment. Taking control of your treatment can make you feel more in control of your life in general.
Get vaccinated for influenza and pneumonia. Staying current with vaccinations can prevent flu and pneumonia from triggering asthma flare-ups.
Identify and avoid asthma triggers. A number of outdoor allergens and irritants — ranging from pollen and mold to cold air and air pollution — can trigger asthma attacks. Find out whatcauses or worsens your asthma, and take steps to avoid those triggers.
Monitor your breathing. You may learn to recognize warning signs of an impending attack, such as slight coughing, wheezing or shortness of breath. But because your lung function may decrease before you notice any signs or symptoms, regularly measure and record your peak airflow with a home peak flow meter.


Identify and treat attacks early. If you act quickly, you're less likely to have a severe attack. You also won't need as much medication to control your symptoms.


When your peak flow measurements decrease and alert you to an oncoming attack, take your medication as instructed and immediately stop any activity that may have triggered the attack. If your symptoms don't improve, get medical help as directed in your action plan.
Take your medication as prescribed. Just because your asthma seems to be improving, don't change anything without first talking to your doctor. It's a good idea to bring your medications with you to each doctor visit, so your doctor can double-check that you're using your medications correctly and taking the right dose.
Pay attention to increasing quick-relief inhaler use. If you find yourself relying on your quick-relief inhaler, such as albuterol, your asthma isn't under control. See your doctor about adjusting your treatment.