Untitled

Mechanism of asthma

airways in your lungs are inflamed and swollen.

Muscles surrounding your airways, irritated by inflammation, tighten and constrict spontaneously.

Membranes in airway linings secrete excess mucus.

The result is narrowed airways and obstructed airflow that typically lead to coughing, wheezing and shortness of breath.

What Is Asthma?

You may not think of asthma as a killer disease. Yet nearly 500,000 Americans are hospitalized annually and more than 5,000 die annually of asthma.

Asthma is a chronic condition that occurs when the main air passages of your lungs, the bronchial tubes, become inflamed. The muscles of the bronchial walls tighten and extra mucus is produced, causing your airways to narrow. This can lead to everything from minor wheezing to severe difficulty in breathing. In some cases your breathing may be so labored that an asthma attack becomes life-threatening.

Yet asthma is a treatable disease, and most flare-ups and deaths can be prevented. In the past 20 years, scientists have gained a better understanding of asthma's cause. New drugs have been developed to replace standard medications. Greater emphasis also is now put on managing your own condition, much as people manage their diabetes with insulin. Together, you and your doctor can work to gain control over your symptoms, reduce the risk of severe attacks and help maintain a normal life.

Signs and Symptoms

Asthma symptoms can range from mild to very severe. You may experience only occasional episodes of asthma with moderate, short-lived symptoms such as wheezing. You might also cough and wheeze most of the time or find that your symptoms become much worse after exposure to an asthma trigger such as pollen, mold or tobacco smoke. In severe cases, an asthma attack leaves you gasping for air.

All asthma attacks give a warning. Learning to recognize warning signs and treating symptoms early can help prevent attacks or keep them from becoming worse.

Warning signs for adults can include:

Increased shortness of breath or wheezing
Disturbed sleep caused by shortness of breath, coughing or wheezing
Chest tightness or pain
Increased need to use bronchodilators — medications that open up airways by relaxing the surrounding muscles
A fall in peak flow rates as measured by a peak flow meter, a simple and inexpensive device that allows you to monitor your own lung function

Warning signs for children may include:

An audible whistling or wheezing when your child exhales
Coughing, especially if the cough is frequent and occurs in spasms
Waking at night with coughing or wheezing
Shortness of breath, which may or may not occur when your child exercises
A tight feeling in your child's chest

Causes

You're more likely to develop asthma if you have an inherited predisposition to the condition and are sensitive to allergens or irritants in the environment. In fact, the inflammation that causes asthma makes your airways overly sensitive to a wide range of environmental triggers.

Asthma can develop at any age — even well into your 70s and beyond. If you're younger than age 30, your asthma is probably triggered by allergies. Many people older than 30 with asthma are also allergic to airborne particles.

For the rest of adults with asthma, particularly older adults, respiratory allergies don't seem to play a role. Instead, exposure to any irritant — from a virus and cigarette smoke, to cold air, and even emotional stress — can trigger wheezing.

In most cases though, asthma results from a combination of allergic and nonallergic responses. You may react to one or more of the following triggers:

Allergens, such as pollen, cockroaches and molds.
Air pollutants and irritants.
Smoking and secondhand smoke.
Respiratory infections, including the common cold.
Physical exertion, including exercise.
Cold air.
Certain medications, including beta blockers such as propranolol (Inderal, Betachron), aspirin and other nonsteroidal anti-inflammatory drugs.
Sulfites — preservatives added to some perishable foods.
Emotional stress.
Gastroesophageal reflux disease (GERD), a condition in which stomach acids back up into your food pipe (esophagus). GERD may trigger an asthma attack or make an attack worse.
Sinusitis.

Risk Factors

For reasons no one quite understands, the number of asthma cases has risen dramatically in the past decade, especially among children living in the inner city. Approximately 11 million Americans have an asthma attack each year, including about 3.8 million children.

In fact, asthma is the most common chronic illness of childhood. Among young children, asthma is more common in boys than in girls. But after puberty asthma becomes more common in girls.

Researchers have identified a number of factors that may increase your chances of developing asthma. These include:

Living in a large urban area, especially the inner city, which may increase exposure to many environmental pollutants.
Exposure to secondhand smoke.
Exposure to occupational triggers, such as chemicals used in farming and hairdressing, and in paint, steel, plastics, and electronics manufacturing.
Having one or both parents with asthma.
Respiratory infections in childhood.
Low birth weight.
Obesity.
Gastroesophageal reflux disease (GERD).

When to Seek Medical Advice

Three key circumstances may lead you to talk to your doctor about asthma:

If you think you have asthma. Wheezing, difficulty breathing, pain or tightening in your chest, or coughing without any other symptoms may all be signs of asthma. Wheezing, especially, is a frequent symptom of asthma in children. Yet some children with asthma never wheeze. Instead, they have recurrent, spasmodic coughs that are often worse at night. If you or your children have frequent coughs that last more than a few days or any other signs or symptoms of asthma, see your doctor.

If you've received the diagnosis of asthma. If you've received the diagnosis of asthma, talk to your doctor about ways to manage your condition. Working as a team, you and your doctor can develop a plan to help you control symptoms, prevent an attack or stop an attack in progress. Don't try to treat asthma yourself. Most asthma deaths result from a lack of proper treatment.

If your medication isn't working. Sometimes your medications may not offer the relief you need. Be sure to contact your physician right away if a prescribed dosage of medication doesn't work for you. In some cases you may not be using your metered-dose inhaler (MDI) correctly. Don't try to solve the problem by taking more medication though — overusing inhalers or taking too much medication can be dangerous.

Screening and Diagnosis

Diagnosing asthma can be difficult. Symptoms can range from mild to very severe and are often similar to those of other lung conditions.

One illness that may mimic asthma is vocal cord dysfunction (episodic laryngeal dysfunction). Signs and symptoms of this condition, which mainly affects women between the ages of 20 and 40, may include shortness of breath, wheezing, coughing and chest tightness. Yet vocal cord dysfunction is typically characterized by an acute onset of severe shortness of breath. If asthma has been diagnosed in you, and your treatments — especially use of a bronchodilator to open your airways — aren't controlling your symptoms, it's possible you may have vocal cord dysfunction. It's also possible that you have both conditions.

Emphysema and early congestive heart failure also may cause symptoms similar to those of asthma. In order to rule out these and other possible conditions, your doctor will likely use several different evaluation methods to arrive at a diagnosis.

In most cases you'll be asked to give a complete medical history and have a physical exam. You may also be given lung (pulmonary) function tests to determine how much air moves in and out as you breathe.

One of the simplest lung function tests uses a peak flow meter to measure the rate at which you can expel air. You can also use a peak flow meter at home to help detect subtle increases in airway obstruction before you notice symptoms. If the readings are lower than usual, it's a sign your asthma may be about to flare up. Your doctor can give you instructions on how to deal with low readings.

Lung function tests are usually done before and after taking a medication known as a bronchodilator to open your airways. If your lung function improves with use of a bronchodilator, it's likely you have asthma.

In some cases your doctor may do a methacholine bronchial challenge. If you have asthma, inhaling the methacholine will cause mild constriction of your airways, which can be measured with a lung function test.

Complications

Asthma accounts for millions of missed school days and workdays annually. It's also a frequent reason for emergency room visits and hospitalizations. You can reduce your risk of severe attacks by making sure your asthma is well controlled and by knowing how to recognize and treat attacks before they occur.

If your asthma attacks are worse at night, you're not alone; many attacks occur between 2 a.m. and 4 a.m. If you wake up in the middle of the night wheezing or short of breath, talk to your doctor about changing or intensifying your treatment.

The long-term use of oral and intravenous corticosteroids to treat asthma attacks may have serious side effects. The use of inhaled corticosteroids, which have fewer side effects, can help you reduce the need for other forms of these drugs.

If you have asthma, you're more likely to be bothered by stomach acid backing up into your esophagus (acid reflux). In some cases acid reflux or gastroesophageal reflux disease (GERD) may actually cause your symptoms. To help prevent this problem, don't eat or drink for several hours before going to bed. You may also find it helpful to elevate the head of your bed.

Treatment

Your doctor will recommend a course of treatment based on you or your child's age and on how persistent the symptoms are. In general, three types of medical treatments are available for asthma:

Bronchodilator medications that relieve acute symptoms or prevent flare-ups
Corticosteroids and other medications that suppress airway inflammation over days, weeks or months
Immunotherapy or allergy desensitization shots
In June 2002, the National Asthma Education and Prevention Program (NAEPP) issued updated asthma treatment guidelines recommending inhaled corticosteroids as a safe, effective and preferred first-line therapy for both children and adults who have persistent asthma. NAEPP is supported and coordinated by the National Heart, Lung and Blood Institute and the National Institutes of Health.
The NAEPP also found that an inhaled corticosteroid plus a long-acting inhaled bronchodilator may work better than inhaled corticosteroids alone for some people with moderate, persistent asthma.
The updated guidelines continue to recommend a "stepwise" approach in which your doctor adjusts the type and the dosage of your medications up or down based upon either improvement or worsening of symptoms over time.

Acute symptom relief

Bronchodilators are medications that open up constricted airways and provide temporary relief of asthma symptoms. Bronchodilators may be short acting or long acting and include:
Beta-2 agonists. Short-acting beta-2 agonists begin working within minutes and last 2 to 4 hours. Long-acting beta-2 agonists last up to 12 hours. The short-acting medications are typically prescribed for relief or prevention of asthma symptoms or flare-ups. The most common drugs, such as albuterol (Proventil, Ventolin) and pirbuterol (Maxair), act quickly to relieve symptoms and can be used as a prevention measure before you exercise or breathe cold air. Prescribed as needed, they may relieve your symptoms for up to 6 hours. Inhaled beta-2 agonists won't correct underlying inflammation, however, and can easily be overused.
Ipratropium (Atrovent). This bronchodilator is an anticholinergic that isn't typically recommended for the immediate relief of asthma symptoms.
Salmeterol (Serevent) and formoterol (Foradil). These long-acting bronchodilators relieve airway constriction for up to 12 hours. They're generally used to prevent symptoms, especially at night. They aren't recommended as a "rescue" medication that can be used for immediate relief during an asthma attack. You usually use salmeterol or formoterol with an anti-inflammatory medication such as inhaled corticosteroids.
Theophylline (Slo-Bid, Theo-Dur). This type of bronchodilator is taken in pill form every day. It's especially helpful for relieving nighttime symptoms of asthma. But theophylline may cause side effects, including nausea and vomiting, severe abdominal pain, diarrhea, confusion, fast or irregular heartbeat, and nervousness. It can also promote GERD or acid reflux by relaxing the lower esophageal sphincter muscle. If you're taking theophylline, get regular blood tests to make sure you're getting the correct dosage.
Long-term anti-inflammatory treatment
Anti-inflammatory drugs are the mainstay medications for asthma. These drugs are taken continually to prevent attacks. Anti-inflammatory drugs reduce inflammation in your airways and prevent blood vessels from leaking fluid into airway tissues. The most widely used of these drugs include:
Corticosteroids. These drugs are the most effective medications for asthma. They're completely different from the steroids that some athletes abuse. Different kinds of corticosteroids include prednisone, prednisolone, cortisone, triamcinolone, hydrocortisone and others. They help decrease the frequency of attacks and lower the dosage of other medications needed to calm symptoms. Long-term use of oral or intravenous corticosteroids can cause serious side effects, however, including decreased resistance to infection, loss of bone mineral (osteoporosis), muscle weakness, high blood pressure and thinning of the skin. Inhaled corticosteroids deliver medication directly to your airways and so have fewer side effects. They're also very effective at controlling most forms of asthma. These medications may include beclomethasone (Vanceril, Beclovent), fluticasone (Flovent), budesonide (Pulmicort), and flunisolide (Aerobid). Advair Diskus is a combination inhaler containing fluticasone and salmeterol. If you're using a metered-dose inhaler form of inhaled corticosteroids, be sure to use a spacer and gargle with water after use to rinse your mouth out. It's important to then spit out this water. This helps reduce the amount of drug that is swallowed and absorbed into the body by way of the stomach. It also reduces side effects such as mouth and throat irritation and oral yeast infections (thrush). Also, because inhaled corticosteroids may affect some children's growth, children taking these medications should have their growth rate regularly monitored. Long-term use of inhaled corticosteroids may increase the risk of cataracts.
Leukotriene modifiers. Introduced in 1996, leukotriene modifiers were the first new class of prescription asthma medications to become available in 20 years. They include montelukast (Singulair), zafirlukast (Accolate) and zileuton (Zyflo). These drugs work by reducing the production, or blocking the action, of leukotrienes — substances released by cells in your lungs during an asthma attack. Leukotrienes cause the lining of your airways to become inflamed, which in turn leads to wheezing, shortness of breath and mucus production. By themselves, leukotriene modifiers are about as effective as theophylline and cromolyn, but used in conjunction with other medications, they may help prevent more attacks. Although generally not as effective as inhaled corticosterioids, leukotriene modifiers are an option
Other drugs. Although they're not effective for everyone, daily use of inhaled cromolyn (Intal) or nedocromil (Tilade) may help prevent attacks of mild to moderate asthma. In some cases they may also help prevent asthma triggered by exercise if taken an hour before any vigorous activity.

Immunotherapy

If you have allergic asthma that can't be easily controlled by avoiding triggers and using medication, allergy desensitization shots (immunotherapy) may help. You'll have skin tests to determine the allergens that cause you the most trouble, followed by a series of injections containing small doses of those allergens. Injections are generally given once a week for a few months, then once a month for a period of 3 to 5 years. Over time, you should lose your sensitivity to the allergens. Immunotherapy isn't for everyone, however. You're most likely to benefit if it's clear you have allergic asthma. In addition, immunotherapy carries the risk of an allergic reaction to the shot. Life-threatening reactions are rare, but can occur.

Prevention

The best way to prevent asthma attacks is to identify and avoid indoor and outdoor allergens and irritants. That's easier said than done, however, because thousands of outdoor allergens and irritants — ranging from pollen and mold to cold air and air pollution — can trigger an attack. A number of indoor allergens, including dust mites, cockroaches, some pets and mold, can do the same. The most common irritant overall is tobacco smoke.

Even if you reduce indoor and outdoor allergens and irritants, managing asthma can be challenging. It often takes ongoing communication and teamwork with your doctor. But by working together, you and your doctor can design a step-by-step plan for living with your condition. In addition to knowing and avoiding your triggers, adopt the following behaviors:

Develop an action plan. With your doctor and health care team, write a detailed plan for taking maintenance medications and managing an acute attack. Then be sure to follow your plan. Asthma is an ongoing condition that needs to be regularly monitored and treated. In addition, taking control of your treatment can make you feel more in control of your life in general.

Monitor your breathing. Like many people, you may recognize your own 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 symptoms, regularly measure your peak airflow with a home peak flow meter.

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 alert you to an impending attack, take your medication as instructed and stop any activity that may have triggered the attack right away. If your symptoms don't improve, be sure to get medical help as directed in your action plan.

Self-Care

Although many people with asthma rely on medications to relieve symptoms and control inflammation, you can do several things on your own to maintain overall health and lessen the possibility of attacks:

Exercise. You don't have to be sedentary if you have asthma. Regular exercise can strengthen your heart and lungs so that they don't have to work so hard. It can also help you lose weight and lower your risk of developing other serious diseases, including cardiovascular disease and diabetes. Aim for 30 minutes of exercise on most days. If you've been inactive, start slowly and try to gradually increase your activity over time. Keep in mind that cold-weather exercises, such as skiing, are more likely to cause wheezing. If you do exercise in cold weather, wear a face mask to warm the air you breathe. And don't exercise if the temperature is below zero. Activities such as golf, walking and swimming are less likely to trigger attacks, but be sure to discuss any exercise program with your doctor.

Use your air conditioner. This helps reduce your exposure to airborne pollen from trees, grasses and weeds. 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. To minimize dust that may aggravate nighttime symptoms, encase mattresses, pillows and box springs in dustproof covers that can be removed and cleaned frequently. Replace bedding made of down, kapok or foam rubber with synthetic materials such as Dacron. Wash sheets, pillowcases and mattress pads weekly in hot water. Replace synthetic pillows every 2 to 3 years.

Maintain optimal humidity. Keep humidity low — 40 percent to 50 percent — in your home and office. If you live in a damp climate, talk to your doctor about using a dehumidifier.

Keep indoor air clean. Have a utility company check your air conditioner and furnace once a year. Change the filters in your furnace and air conditioner according to the manufacturer's instructions. Also consider installing a small-particle filter in your ventilation system. If you use a humidifier, change the water daily.

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. Because cleaning stirs up dust, however, wear a mask or, if you can, have someone else clean.

Limit use of contacts. Try substituting eyeglasses for your contact lenses when the pollen count is high. Pollen grains can become trapped under the lenses.

Coping Skills

Asthma presents many physical challenges, but it can also cause other kinds of distress. You may sometimes become frustrated, angry or depressed because you need to cut back on your usual activities to avoid environmental triggers. You may also feel hampered or embarrassed by the symptoms of the disease and by complicated management routines.

But asthma doesn't have to be a limiting or depressing condition. The best way to overcome anxiety and a feeling of helplessness is to understand your condition and take control of your treatment. Here are some suggestions that may help:

Identify the things that trigger your symptoms. This can be one of the most important ways to take control of your life. Also take peak flow measurements regularly and follow your action plan for using medications and managing attacks.

Pace yourself. Take breaks between tasks and avoid activities that make your symptoms worse.

Make a daily to-do list. This may help you avoid feeling overwhelmed. Reward yourself for accomplishing simple goals.

Talk to others with your condition. Chat rooms and message boards on the Internet or support groups in your area can connect you with people facing similar challenges and let you know you're not alone.

If you have a child with asthma, be encouraging and supportive. Focus attention on the things your child can do, not on the things he or she can't do. Involve teachers, school nurses, coaches, friends and relatives in helping your child manage an asthma condition.

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Home Control Of Allergies And Asthma

AIR PARTICLES WE BREATHE

Many particles of different types and sizes are carried in the air we breathe. Some large particles may settle on the walls and furniture in your home. Other large particles are removed by your nose and mouth when you inhale. Smaller particles are breathed deep into the lungs.

Asthma may be triggered by both the large and small particles. Some air particles come from the indoors. Others are carried in the outdoor air. Outdoor particles come into your home through windows, doors, and heating systems.

For most people, the indoor air particles cause no problems. But people with allergic symptoms including asthma can have problems, right in their own home.

ASTHMA AND ALLERGY "TRIGGERS"

If you or someone you know have allergic symptoms or asthma, you are sensitive to "triggers," including particles carried in the air. These "triggers" can set off a reaction in your lungs and other parts of your body. Triggers can be found indoors or outdoors. They can be simple things like:

Cold air.
Tobacco smoke and wood smoke.
Perfume, paint, hair spray, or any strong odors or fumes.
Allergens (particles that cause allergies) such as dust mites, pollen, molds, pollution, and animal dander - tiny scales or particles that fall off hair, feathers or skin - and saliva from any pets.
Common cold, influenza, and other respiratory illnesses.
You may be able to add more triggers to this list. Other things may also trigger your asthma or allergies. It's important to learn which triggers are a problem for you. Ask your doctor to help. Your doctor my suggest:

Keeping an asthma diary.
Skin testing to test for allergies.
Finding triggers isn't always easy. If you do know your triggers, cutting down exposure to them may help avoid asthma and allergy attacks.
If you don't know your triggers, try to limit your exposure to one suspected trigger at a time. Watch to see if you get better. This may show you if the trigger was a problem for you.

OUTDOOR AIR, INDOOR AIR AND AIR-CONDITIONING

Controlling your exposure to triggers outdoors is hard. You may have to avoid outdoor air pollution, pollen, and mold spores. Any time air pollution and pollen levels are high, it's a good idea to stay indoors.

The air at home is easier to control. Some people with asthma and allergies notice that their symptoms get worse at night. Trigger controls in the bedroom or wherever you sleep need the most care.

Air-conditioning can help. It allows windows and doors to stay closed. This keeps some pollen and mold spores outside. It also lowers indoor humidity. Low humidity helps to control mold and dust mites.

Avoid too much air-conditioning or too much heat. Room air temperature should be comfortable for someone with allergies or asthma. Some people can't tolerate a big change in temperature, particularly from warm to cold air.

There are some devices that effectively remove particles from air. Their usefulness in reducing allergy symptoms is under study.

TRIGGER CONTROLS

Here are some common triggers and some ways to help control them at home:

Tobacco Smoke

Smoke should not be allowed in the home of someone with asthma or allergies. Ask family members and friends to smoke outdoors. Suggest that they quit smoking. Your local American Lung Association can help. Ask your Lung Association how you can help a family member or friend quit smoking.

Wood Smoke

Wood smoke is a problem for children and adults with asthma and allergies. Avoid wood stoves and fireplaces.

Pets

Almost all pets can cause allergies, including dogs, cats and especially small animals like birds, hamsters and guinea pigs. All pets should be removed from the home if pets trigger asthma and allergy symptoms.

Pet allergen may stay in the home for months after the pet is gone because it remains in house dust. Allergy and asthma symptoms may take some time to get better.

If the pet stays in the home, keep it out of the bedroom of anyone with asthma or allergies. Weekly pet baths may help cut down the amount of pet saliva and dander in the home.

Sometimes you hear that certain cats or dogs are "non-allergenic." There really is no such thing as a "non-allergenic" cat or dog, especially if the pet leaves dander and saliva in the home. Goldfish and other tropical fish may be a good substitute.

Cockroaches

Even cockroaches can cause problems, so it's important to get rid of roaches in your home. Small pieces of dead roaches and roach droppings settle in house dust and can end up in the air you breathe.

Like humans, roaches need food and water and a place to live. Help keep your home roach free by storing food in sealable containers and keeping crumbs, dirty dishes and other sources of food waste cleaned up; fixing leacks and wiping up standing water; and cleaning up clutter where roaches find shelter.

If you still have problems and you have to choose a pesticide, be sure to use it safely, and as directed on the label. Baits are less likely than sprays or foggers to harm your lungs.

Indoor Mold

When humidity is high, molds can be a problem in bathrooms, kitchens, and basements. Make sure these areas have good air circulation and are cleaned often. The basement in particular may need a dehumidifier. And remember, the water in the dehumidifier must be emptied and the container cleaned often to prevent forming mildew.
Molds may form on foam pillows when you perspire. To prevent mold, wash the pillow every week, dry thoroughly and make sure to change it every year.
Molds also form in houseplants, so check them often. You may have to keep all plants outdoors.

Strong Odors or Fumes

Perfume, room deodorizers, cleaning chemicals, paint, and talcum powder are examples of triggers that must be avoided or kept to very low levels.

Dust Mites

Dust mites are tiny, microscopic spiders usually found in house dust. Several thousand mites can be found in a pinch of dust. Mites are one of the major triggers for people with allergies and asthma. They need the most work to remove.
Following these rules can also help get rid of dust mites:
Put mattresses in allergen-impermeable covers. Tape over the length of the zipper.
Put pillows in allergen-permeable covers. Tape over the length of the zipper. Or wash the pillow every week.
Wash all bedding every week in water that is at least 130 degrees F. Removing the bedspread at night may help.
Don't sleep or lie down on upholstered (stuffed) furniture.
Remove carpeting in the bedroom.
Clean up surface dust as often as possible. Use a damp mop or damp cloth when you clean. Don't use aerosols or spray cleaners in the bedroom. And don't clean the room when someone with asthma or allergies is present.
Window coverings attract dust. Use window shades or curtains made of plastic or other washable material for easy cleaning.
Remove stuffed furniture and stuffed animals (unless the animals can be washed), and anything under the bed.

Closets need extra care. They should hold only needed clothing. Putting clothes pin a plastic garment bag may help. (Do not use the plastic bag that covers dry cleaning).

Dust mites like moisture and high humidity. Cutting down the humidity in your home can cut down the number of mites. A dehumidifier may help.

Air cleaning devices, including portable units and central filtration systems may be helpful in reducing some indoor air pollutants when used with effective source control and ventilation. Ask your doctor for advice about air cleaning devices. If you decide to use one, make sure it removes particles efficiently over an extended period of time and does not produce ozone.

GENERAL RULES TO HELP CONTROL THE HOME ENVIRONMENT

Controlling the home environment is a very important part of asthma and allergy care. Some general rules for home control for all members of the family are:
Reduce or remove as many asthma and allergy triggers from your home as possible.
If possible, use air filters and air conditioners -- and properly maintain them -- to make your home cleaner and more comfortable.
Pay attention to the problem of dust mites. Work hard to control this problem in the bedroom.
Vacuum cleaners stir up dust and allergens in the air. A vacuum cleaner with a high efficiency air filter or a central vacuum cleaner with a collection bag outside the home may be of limited value. Anyone with asthma or allergies should avoid vacuuming. If vacuuming must be done, a dust mask may help.

Spring Mattresses Rather Than Foam Reduce Exposure to House Dust Mite Allergens

A DGReview of :"House-dust mites and mattresses" 05/31/2002 By Elda Hauschildt

Replacing foam mattresses with spring mattresses can help reduce exposure to house dust-mite allergens.

Foam mattresses with covers are four times as likely to house mite faeces and eight times as likely if they don't have covers.

Norwegian and American researchers point out that surprisingly few studies have evaluated the allergen content in different types of mattresses, despite considerable efforts to develop anti-dust mite strategies.

They investigated the presence of mite faeces as an indicator of mite-allergens in both spring and foam mattresses in the homes of 152 school children in northern Norway.

Investigators from the University of Tromso in Norway and the University of California in Berkley collected dust samples from 24 foam mattresses without covers, 68 foam mattresses with covers and 24 spring mattresses. They used a guanine colorimetric paper test to detect mite faeces.

esults show mite faeces were in 40.5 percent of the dust samples from foam mattresses without covers, in 26.3 percent of the foam mattresses with covers and in only 12.5 percent of the spring mattresses.

The presence of mite faeces was associated with seven factors: signs of dampness, mattress age, mattress cleaning, frequency of vacuuming in the bedroom, mechanical ventilation, bedroom temperature and bedroom relative humidity.

Allergy, 2002; 57: 538-542. "House-dust mites and mattresses"

Heartburn Drug May Relieve Severe Asthma

17 minutes ago

By Janice Billingsley

HealthScoutNews Reporter

MONDAY, Oct. 21 (HealthScoutNews) -- People suffering from severe asthma as well as acid reflux disease might find the medicine they take for the reflux provides some crossover relief for their breathing problems.

In a double-blind, six-month study of 207 asthma and acid reflux sufferers, those patients who took daily acid-reducing medicine along with their asthma medicine had fewer severe asthma attacks and an improvement in their quality of life, says Dr. Michael Littner, a professor of medicine at University of California in Los Angeles and the study's lead author.

"Those patients with asthma and acid reflux symptoms who were taking two maintenance medicines, such as inhaled corticosteroids and long-acting beta-2 agonists, for asthma as well as lansoprazole had a significant, clinically important improvement," says Littner, who reported the findings today at the American College of Gastroenterology's annual meeting in Seattle.

Lansoprazole is a category of drug called a proton pump inhibitor (PPI (news - web sites)), which inhibits the production of stomach acid and is used in treating acid reflux disease. Tap Pharmaceutical Products Inc. manufactures lansoprazole under the name Prevacid, and was the sponsor of the study.

The benefits, Littner says, were that those on lansoprazole reported fewer severe asthma attacks, called exacerbations, than did those who took a placebo.

"In the emotions domain of the questionnaires they filled out, they reported a better sense of general well-being," he adds.

The improvements, though, were seen only in those with severe asthma, which was defined in the study as patients who took more than one long-term maintenance medication for their disease. Study participants who took only one asthma medicine showed no improvement in their asthma with the lansoprazole.

Dr. Timothy Wang, chief of gastroenterology at the University of Massachusetts Medical School, says asthma and gastroesophageal reflux disease (GERD) seem to be closely linked, with each one leading to the worsening of the other. He also says there may be a small subgroup of asthma patients who are helped by taking acid inhibitors, but most patients will show no benefit.

While this study has the advantage of being a randomized, double-blind study, he says "since all these patients had acid reflux disease in addition to asthma, they should have been taking the acid reflux medicine anyway, regardless of their asthma."

Littner responds that the study participants had not been taking PPIs on a daily basis before the study. Asthma sufferers who were already taking daily PPI medication were not included in the study because if they were getting relief, the doctors did not want to take them off their medicines and put them on a placebo.

"The patients in the study were those who thought their heartburn was being controlled by occasional antacids. When they were having a pizza, they'd take an antacid, or maybe a PPI, but normally did not take daily medications for reflux symptoms," he says.

In the 24-week study, 207 regular asthma patients, recruited from 32 medical centers throughout the country, were divided into two groups -- one taking 30 milligrams daily of Prevacid, and the other taking a placebo. About half of the patients took more than one asthma medication, and they were divided equally between the Prevacid and placebo groups.

has been halted because three companies are in court squabbling over rights to the treatment.

In Some, Throat Clearing First Sign of Asthma

University of Crete researchers looked at a group of children who, according to their parents, often cleared their throats.

About 58 percent of those children had not been diagnosed with asthma. Half of the undiagnosed children underwent tests of lung function, and the results showed that those youngsters did, in fact, have the condition.

"They all had a very mild form of asthma," Dr. Eva C. Mantzouranis told Reuters Health.

She suggested that parents of a child who constantly clears his throat for no obvious reason should consider getting the child tested for asthma, even if he has no other symptoms of the condition.

However, the typical questions doctors ask parents to determine whether children have asthma do not include throat clearing as a symptom, Mantzouranis noted. Children with asthma do better if they are treated earlier rather than later, she said, and doctors who don't ask about throat clearing symptoms may miss some early cases of the condition, she said.

"It is important to start treatment early, because the prognosis is better," Mantzouranis explained.

"I would definitely add that (question about throat clearing) to my standard questions for asthma," she added.

According to the American Lung Association, asthma is the leading serious, chronic illness in childhood, diagnosed in at least 7.7 million people younger than 18 in the US alone.

While wheezing and coughing are considered common symptoms of asthma, other symptoms that also signal the disease has arrived may be less recognized, Mantzouranis and her colleagues note.

In an interview, Mantzouranis explained that she began to suspect that throat clearing could be a sign of asthma when some parents of children being treated for asthma reported that their children had also stopped constantly clearing their throats, a habit they had thought of as a "tic."

To determine whether throat clearing was a sign of early asthma, the authors looked at questionnaires given to the parents of 2,609 children aged between three and five years old who attended a daycare center. The questionnaires asked parents about typical symptoms of asthma and included one additional query: "does your child have a habit of clearing his or her throat often?"

Almost 18 percent of the children had been diagnosed with asthma during the previous year, and another 24 percent had been told they had the disease prior to the previous year, Mantzouranis and her colleagues report.

Parents of 106 children said they were frequent throat clearers, 61 of whom had never been diagnosed with asthma, nor had any symptoms of the condition.

To test whether these supposedly asthma-free children did, in fact, have the disease, the researchers measured lung function in 30 of the youngsters old enough to perform the test.

This test revealed that these children, on average, had reduced lung function. After doctors gave them treatment for asthma, however, both their throat clearing and lung function improved.

Seeing an improvement in symptoms after receiving asthma medication is "consistent with the diagnosis of clinically unrecognized asthma," Mantzouranis and her colleagues write.

Mantzouranis explained that children with asthma have sensitive airways that react poorly to different stimulants. In many children, this exposure leads to coughing or wheezing. But in others with a less severe form of the condition, their reaction is not strong enough to cause a cough or wheeze, and exposure to a stimulant may result in simple throat clearing, she said.

SOURCE: The New England Journal of Medicine (news - web sites) 2003;348:1502-1503.

Controlling Sinus Problems Cuts Asthma Risk

Grab the phone and call your doctor to see if you're suffering from one of several related respiratory problems: sinusitis, allergies -- even asthma.

The reason? If you control the symptoms of sinusitis or allergies early on, you're not only getting relief from those illnesses, you're increasing your chances of protecting yourself from asthma, doctors say.

The proof is in the statistics. The people most likely to have asthma -- an estimated 17 million Americans -- are those who suffer from sinusitis or allergies. In fact, 20 percent to 40 percent of those with sinusitis or allergies have asthma, while only 5 percent of the general population has asthma.

Conversely, 80 percent of asthmatics also have nasal illnesses, compared to 20 percent to 40 percent of the general population. So again, it's important to try to isolate and treat each illness promptly, experts say.

"You need to see a doctor to make a diagnosis, and to reduce the complications of other illnesses by treating your condition early and correctly," says Dr. Y. Howard Pung, director of Georgetown University Medical Center's allergy and immunology division in the pediatric department.

Another reason early diagnosis is important for respiratory illnesses is that, left untreated, they can become chronic.

"There is a chronic nature to sinus disease and asthma, plus the danger of secondary infection," explains Dr. Keith Wahl, chief of otolaryngology at Scripps Memorial Hospital in La Jolla, Calif. "And sinus infection leads to bronchitis."

Sinus problems, allergies and asthma are three different conditions. But because they all affect the respiratory tract, one can aggravate or trigger another, Wahl says.

"Air starts in the nose and ends up in the lungs, and it can be that the reaction of what's going on in one area is what triggers responses in other areas," he says. "All are inflammatory responses."

With seasonal allergies, the body mistakenly identifies a common particle like tree pollen as an enemy and releases a substance to fight it. However, it's that substance, called histamine, which causes inflammation of the nasal tract and results in the runny noses and itchy eyes so familiar to allergy sufferers, Pung says.

Sometimes, Pung says, the inflammation narrows the nasal passages so much that mucus builds up in the sinus, cannot drain and eventually becomes infected with bacteria. Or this mucus buildup can be caused by anatomical abnormalities that result in nasal passages that are too narrow. Whatever the cause, the resulting infection is called sinusitis and often requires antibiotics.

Asthma is a much more serious condition that occurs when the lungs' main air passages become inflamed, causing the airways to constrict, making breathing difficult.

So it's important to determine the cause of the inflammation, get it treated and understand that one respiratory problem could be related to another, Wahl and Pung say.

"If you go to the doctor for asthma, be mindful that you may have a relationship with allergy (and sinusitis), and that your nose may be involved," Wahl says.

When Pung examines patients for allergies, he makes sure to ask them questions aimed at diagnosing other sinus problems -- such as sinusitis -- and asthma as well.

"I will ask the patient if he coughs or wheezes when exercising, laughing, drinking a cold drink or eating ice cream, or when he is exposed to cold air," Pung says, all of which are signs of asthma.

Similarly, questions about possible sinusitis include whether the patient has headaches, post-nasal drip, chronic bad breath or a loss of smell, Pung says.

Treatment for each illness is condition-specific. But all therapies include identifying the inflammation; controlling it with medicines, called "rescue medicines"; and then using other medicines, called "preventive/controller" medicines, to keep the symptoms from returning, Pung says.

In sinusitis, for instance, treatment can include decongestants to reduce congestion, antibiotics to control a bacterial infection, pain relievers to reduce any discomfort, and steroid nasal sprays to reduce the inflammation in the nose. People whose symptoms persist more than three weeks have a condition called chronic sinusitis that affects 32 million American adults annually. For these patients, doctors are beginning to prescribe, among other treatments, intranasal nebulized antibiotics, anti-fungals, and anti-inflammatories to topically target sinus infections.

The bottom line, both doctors say, is that no matter what illness you have, the sooner you're diagnosed and treated, the better off you'll be.

"If you're a person who seems to have seasonal inflammatory reactions or if wheezing occurs, you should see a physician," Wahl says.