The U.S. National Asthma Education and Prevention Program (NAEPP) guidelines for the diagnosis and management of asthma recommend:
Symptoms of asthma include:
The word asthma originates from an ancient Greek word meaning panting. Essentially, asthma is an inflammatory lung condition that makes it difficult to breathe properly.
When any people inhale, the air travels through the following structures:
Asthma is a chronic condition in which these airways undergo changes when stimulated by allergens or other environmental triggers. Such changes appear to be two specific responses:
These actions in the airway cause coughing, wheezing, and shortness of breath (dyspnea), the classic symptoms of asthma.
In the hyperreactive response, smooth muscles in the airways constrict and narrow excessively in response to inhaled allergens or other irritants. Airways in everyone's lungs respond by constricting when exposed to allergens or irritants, but there are major differences in the hyperreactive response that occurs in people with asthma:
The hyperreactive stage is followed by the inflammatory response, which generally contributes to asthma in the following way:
Inflammation appears to be present in the lungs of all patients with asthma, even those with mild cases, and plays a key role in all forms of the disease.
Doctors don’t fully understand the causes of asthma. They believe the disorder is most likely caused by a combination of genetic (inherited) factors and environmental triggers (such as allergens and infections). Asthma tends to run in families, so children whose parents have asthma are more likely to develop it themselves.
Asthma and allergies often coexist, and the allergic response plays a strong role in childhood asthma. About 70 - 85% of children with asthma also have allergies. Some studies suggest that children who have allergies are also at greater risk for developing asthma as adults. However, only a minority of children with allergies have asthma.
In people with allergies, the immune system overreacts to exposure to allergens. Allergic asthma is triggered by inhaling certain substances (allergens), such as:
An asthma attack can be induced or aggravated by direct irritants to the lungs. Studies indicate that the more indoor allergens to which a child is allergic, the higher the child's risk for severe asthma. Important irritants include:
The role of early childhood respiratory and intestinal infections is very complex. Viral respiratory infections certainly worsen existing asthma, but the most common ones are unlikely to cause childhood asthma. In fact, early respiratory and intestinal infections may offer some protection against asthma. The “hygiene hypothesis” theorizes that early exposure to dirt, germs, and certain infections may help stimulate the immune system to help prevent childhood asthma.
Studies suggest that most respiratory infections are not important causes of asthma in children, except in certain cases. An important exception is the respiratory syncytial virus (RSV), which is associated with the development of asthma. RSV is the major viral cause of infant pneumonia. Studies also indicate that infants who have reduced lung function within a few days after birth are at increased risk of developing asthma by the time they are 10 years old.
Common respiratory infection viruses that cause colds (such as the rhinovirus) may be associated with the development of asthma in some people. More likely, these viruses do not directly cause asthma, but they worsen asthma in children who already have it. Rhinovirus is the most common infection associated with asthma attacks.
Research indicates that children who have viral-induced wheezing during infancy may be at increased risk for later development of asthma. However, many children outgrow attacks of intermittent wheezing.
Asthma affects about 7 million American children. Asthma has dramatically increased worldwide over the past few decades, in both developed and developing countries. Asthma is the most common chronic childhood illness. About half of all cases of asthma develop before the age of 10, and about 80% of patients develop symptoms before they are 5 years old.
Among younger children, asthma develops twice as frequently in boys as in girls, but after puberty it is more common in girls.
African-American children have significantly higher rates of asthma than Caucasian children. Hispanic children are also at higher risk. Both groups of minority children are more likely to have fatal asthma than Caucasian children. Ethnicity and genetics, however, are less likely to play a role in these differences than socioeconomic differences, such as having less access to optimal health care and a greater likelihood of living in an urban area. Caucasian children who live in cities also face a high risk for asthma.
A variety of pregnancy and perinatal factors have been associated with risk for asthma, although none are very well studied or proven. Results from studies include:
There is a strong association between obesity and asthma. People who are overweight (body mass index greater than 25) also have more difficulty getting their asthma under control. Weight loss in anyone who is obese and has asthma or shortness of breath helps reduce airway obstruction and improve lung function.
GERD. At least half of patients with asthma also have gastroesophageal reflux disease (GERD), the cause of heartburn. It is not entirely clear which condition causes the other or whether they are both due to common factors. Treating GERD does not appear to improve asthma control.
Aspirin-Induced Asthma. Aspirin-induced asthma (AIA) is a condition in which asthma gets worse after taking aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs). AIA often develops after a viral infection. It is a particularly severe asthmatic condition, associated with many asthma-related hospitalizations. In about 5% of cases, aspirin is responsible for a syndrome that involves multiple attacks of asthma, sinusitis, and nasal congestion. Such patients also often have polyps (small benign growths) in the nasal passages.
Patients with aspirin-induced asthma (AIA) should avoid aspirin and other NSAIDs, including ibuprofen (Advil and other brands, generic) and naproxen (Aleve, generic). Some research indicates that acetaminophen (Tylenol, generic) may also trigger or worsen asthma, particularly in children. Although this link is not yet proven, parents whose children have asthma should be alert for this possible effect.
Asthma is the third leading cause of hospitalization in children under age 15. The condition can be very serious in children, particularly those younger than age 5, because their airways are very narrow.
Asthma death rates have steadily declined, and asthma is now only rarely fatal in children. Even low mortality numbers are unacceptable, however, since asthma deaths are largely preventable.
Factors associated with an increased risk of death from asthma in children include:
African-American children have more than six times the death rate of Caucasians in the age groups of 4 years and younger and 15 - 24 years. Hispanic children also have a higher risk.
Asthma generally improves as children get older, although most school-age children with persistent asthma will still experience symptoms through adolescence. Some children outgrow their asthma by adulthood. In general, the more severe the childhood asthma, the greater the likelihood that it will persist.
Severe asthma can cause long-lasting damage and possibly permanent scarring in some patients. The risk for such injury is highest when asthma strikes children in their first 3 - 5 years. There does not appear to be any significant risk for long-term lung damage for children who develop mild-to-moderate persistent asthma between ages 5 - 12. Children adapt well to living with asthma, and even with severe asthma they can function as well as healthy children in virtually all areas of life.
In children with asthmatic symptoms, it is important to first consider as a possible cause inhaled foreign objects such as peanuts; viral infections such as croup; and bacterial infections, which may be accompanied by high fever and progress rapidly. Any child who has frequent coughing or respiratory infections should be checked for asthma.
The classic symptoms of an asthma attack include:
Any of these symptoms may worsen with exercise, viral infections, exposure to irritants, stress, or changes in weather.
The end of an attack is often marked by a cough that produces thick, stringy mucus. After an initial acute attack, inflammation lasts for days to weeks, often without symptoms. (The inflammation itself must still be treated, however, because it usually causes relapse.)
The following signs and symptoms may indicate a life-threatening situation:
Asthma often progresses very slowly, but it may sometimes develop to a fatal or near-fatal attack within a few minutes. It is very difficult to predict when an attack will become very serious.
Exercise-induced asthma (EIA) is a limited form of asthma in which exercise triggers coughing, wheezing, or shortness of breath. This condition generally occurs in children and young adults, most often during intense exercise in cold dry air. Symptoms are generally most intense about 10 minutes after exercising, then gradually resolve.
EIA is triggered only by exercise and is distinct from ordinary allergic asthma in that it does not produce a long period of airway hyperactivity, as allergic asthma does. (However, some people have both forms of asthma.) People who have only EIA do not need long-term maintenance therapy.
Asthma occurs primarily at night (nocturnal asthma) in as many as 75% of patients with asthma. Attacks often occur between 2 and 4 a.m. Nighttime attacks may indicate poor asthma control.
If symptoms and a patient's history strongly suggest asthma, the doctor will usually perform tests called pulmonary function tests to confirm the diagnosis and determine the severity of the disease.
Using a spirometer, an instrument that measures the air taken into and exhaled from the lungs, the doctor will determine several values:
If the airways are obstructed, these measurements will fall. Depending on the results, the doctor will take the following steps:
The patient may receive skin or blood allergy tests, particularly if a specific allergen is suspected and available for testing. Allergy skin tests help diagnose for allergic asthma, although they are not recommended for people with year-round asthma.
While medications play an essential role in the management of asthma, appropriate management of asthma also involves:
The severity of asthma is classified into four groups: Intermittent, Mild Persistent, Moderate Persistent, and Severe Persistent. Six specific components of severity are used to classify patients. These components are:
Once patients are placed into a certain severity grouping, there is a recommended treatment approach, which also takes into consideration three age groupings:
Medications for asthma fall into two categories:
The goal of asthma therapy is to maximize long-term control of the illness with medications and other treatment approaches, thereby minimizing the frequency of asthma symptoms and asthma attacks. Parents can greatly reduce the frequency and severity of their children’s asthma attacks by understanding the difference between coping with asthma attacks and controlling the disease over time.
Unfortunately, many patients do not understand the difference between medications that provide rapid, short-term relief and those that are used for long-term symptom control. Many patients with moderate or severe asthma overuse their short-term medications and underuse their corticosteroid medications. The overuse of bronchodilators can have serious consequences; not using steroids can lead to permanent lung damage.
These are the signs of well-controlled asthma:
A stepwise approach is recommended for treating asthma. Medications and dosages are increased when needed, and decreased when possible. Based on a patient’s age and asthma severity, there are specific recommendations regarding whether to use long-term control medications and which ones to use. Patient education, environmental control measures, and management of any other conditions are also included. Doctors may always adjust these recommendations based on a specific patient.
In choosing therapy, doctors must also consider the risk an individual patient has for more severe exacerbations. Factors that may contribute to this include parental history of asthma, atopic dermatitis, and known sensitivity to different allergens or foods. Patients should be reevaluated within 2 - 6 weeks of starting therapy to assess response.
Key points regarding recommendations for children 4 years old and younger include:
Key points regarding recommendations for children 5 years and older include:
The variation between age groups consists mostly of which medications are recommended and how soon to start various medications and treatments.
Most asthma drugs are inhaled using various forms of inhalers or nebulizers. Inhaled drugs must be used regularly as prescribed and the patient carefully trained in their use in order for them to be effective and safe. Studies suggest that many children fail to use the devices properly, although newer devices are easier to use than others. The basic devices are the metered-dose inhaler (MDI), dry powder inhalers, and nebulizers.
Metered-Dose Inhaler. The standard device for administering any asthma medication is the metered-dose inhaler (MDI). This device, particularly when used with a spacer, allows precise doses to be delivered directly to the lungs. (The spacer is a tube that is attached to the inhaler. It serves as a holding chamber for the medication that is sprayed by the inhaler.) MDI-delivered drugs must be used regularly as prescribed and the patient carefully trained in their use in order for them to be effective and safe. Some patients hold the MDI too close to their mouths, or even inside them. Others may exhale too forcefully before inhalation.
The spacer helps improve medication delivery by allowing the patient additional time to inhale. In addition, MDIs can continue to deliver propellant even after the drug has been used up. Patients should track their medicine and throw the device away when the last dose has been administered.
Dry Powder Inhalers. Dry powder inhalers (DPIs) deliver a powdered form of beta2-agonists or corticosteroids directly into the lungs. Some patients find that they are easier to manage than MDIs. Humidity or extreme temperatures can affect DPIs' performance, so they should not be stored in humid places (bathroom cabinets) or locations subject to high temperatures (glove compartments during summer months).
Dry-powder may cause tooth erosion. Children are advised to rinse their mouths out right after using these inhalers and to brush twice a day with fluoride toothpaste.
Nebulizers. A nebulizer is a machine that delivers a fine spray of medication-containing liquid. Nebulizers are often used for children younger than 3 years and sometimes for older children who have difficulty using the MDI. It takes 5 - 10 minutes to administer medication using a nebulizer. Because the spray is less targeted than with the inhaler, it must deliver large amounts of the drug. This increases the risk for toxicity and severe side effects.
Children who can manage an inhaler should not use nebulizers. Their use has been associated with a higher rate of hospitalizations and longer duration of symptoms than inhalers. If children must use an albuterol nebulizer, parents should be sure that it does not contain the preservative benzalkonium, which actually narrows the airways. Recent studies suggest spacers may be better than nebulizers for children, and they shorten the time spent in emergency rooms. Studies also indicate that with the use of a face mask and a spacer, the MDI works well even for infants in the emergency room and may prove to be useable at home.
Asthma can trigger a difficult emotional-physical cycle:
Caregivers must first focus on reducing their own anxiety, which can heighten a child's own fears. The next step is to help the child relax. One method for this is as follows:
This exercise both relaxes the child and discourages shallow, oxygen-poor breathing. Massaging the child in gentle circles on the chest is relaxing and may also loosen mucus.
Other recommendations include:
Visits by home health care nurses or social workers may help if the family is having trouble managing the asthma and following prescribed treatments. Often, having the home evaluated for triggers can be very helpful.
These medications quickly control acute asthma attacks.
Beta2-agonists serve as bronchodilators, relaxing and opening constricted airways during an acute asthma attack. A short-acting inhaled beta2-agonist, taken as needed, is often the only medication used by children with chronic mild asthma.
Albuterol (Proventil, Ventolin), called salbutamol outside the U.S., is the standard short-acting beta2-agonist in the United States.
Short-acting bronchodilators are usually administered through inhalation and are effective for 3 - 6 hours. They relieve the symptoms of acute attacks, but they do not control the underlying inflammation. If asthma continues to worsen with the use of these drugs, a doctor may prescribe corticosteroids or other drugs to treat underlying inflammation.
Side Effects of Beta2-Agonists. Side effects of all beta2-agonists may include:
Loss of Effectiveness and Overdose. Short-acting beta2-agonists become less effective when taken regularly over time, which increases the risk for overuse. Overdose can be serious and in rare cases even life threatening.
Two inhaled drugs, ipratropium bromide (Atrovent) and tiotropium (Spiriva), act as bronchodilators over time. Neither is highly beneficial for acute asthma attacks. Moreover, the drugs are not approved specifically for asthma. Some parents, however, report these drugs are helpful for treating wheezing in infants. The drugs are also sometimes used in the emergency room to treat children with severe asthma to enhance the effects of intravenous beta2-agonists.
Common oral corticosteroids include prednisone/prednisolone, dexamethasone, methylprednisolone, and hydrocortisone. They reduce inflammation very effectively. They are most commonly prescribed for asthma flareups that do not respond to inhaler medications. Doctors may provide a written prescription for patients to keep on hand, with specific instructions about when to fill it. Usually, the dosage starts out higher and is gradually reduced over a 5 - 7 day period. Prolonged use of oral steroids has widespread and sometimes serious side effects, so they are not generally given to children for longer than 5 - 7 days.
These medications are taken on a regular basis to prevent asthma attacks and control chronic symptoms.
Corticosteroids, also called glucocorticoids or steroids, are powerful anti-inflammatory drugs. Steroids are not bronchodilators (they do not relax the airways) and have little immediate effect on symptoms. Instead, they work over time to reduce inflammation and prevent permanent injury in the lungs. They can also help prevent asthma attacks from occurring. The use of inhaled corticosteroids in patients with moderate-to-severe asthma reduces the risk of rehospitalization and death from asthma.
Taking a corticosteroid drug through an inhaler makes it possible to provide effective local anti inflammatory activity in the lungs with very few side effects elsewhere in the body. (By contrast, oral steroids have considerable side effects throughout the body.) Inhaled corticosteroids are recommended as the primary therapy for any patient needing long-term control medications for persistent asthma.
Examples of inhaled corticosteroids:
Inhaled corticosteroids are the preferred first-line therapy for children with asthma. However, doctors caution against corticosteroids for infants and toddlers with mild asthma and urge close monitoring, especially for children under age 5 with severe asthma who are receiving high doses.
Inhaled corticosteroids and growth in children is a common concern. However, a number of studies report only a slight effect (about half an inch) on children's growth, which may be only temporary. These growth changes are mostly when higher doses are being used. Poorly controlled asthma can also affect growth.
Side effects of inhaled steroids may include:
Long-acting beta2-agonists (LABAs) are used for preventing an asthma attack (not for treating attack symptoms). These drugs should never be used alone in the treatment of asthma in adults or children. They can be dangerous when used alone, because they can mask asthma symptoms, and they can increase the risk of asthma death unless paired with an inhaled steroid. LABAs should only be used in combination with an asthma controller medication, such as an inhaled corticosteroid. LABAs should be used for the shortest time possible, and should only be used by patients whose asthma is not adequately controlled by asthma controller medications.
Salmeterol-fluticasone (Advair), formoterol-budesonide (Symbicort), and mometasone-formoterol (Dulera) are long-acting beta2 agonists products combined with a steroid in a single inhaler that are used for treatment of moderate-to-severe asthma. Advair is approved for children ages 4 years and older, and Symbicort and Dulera are approved for children ages 12 years and older.
Leukotriene antagonists (also called anti-leukotrienes or leukotriene modifiers) are oral medications used for prevention, NOT for treating acute asthma attacks.
Leukotriene antagonists include montelukast (Singulair), zafirlukast (Accolate, generic), and zileuton (Zyflo). These drugs are considered an alternative for long-term control of asthma. Other potential uses include preventing exercise-induced asthma.
Side Effects and Complications. Upset stomach, headache, and sore throat are the most common side effects of leukotriene antagonists. Because these drugs can raise liver enzyme levels, patients may need periodic liver tests.
Mental health difficulties and behavioral changes have been associated with these medications. These mood problems include agitation, aggression, anxiousness, dream abnormalities, hallucinations, depression, insomnia, irritability, restlessness, tremor, and suicidal thinking. Patients who take a leukotriene antagonist drug should be monitored for signs of behavioral and mood changes. Doctors should consider discontinuing the drug if patients exhibit any of these symptoms.
Omalizumab (Xolair) is FDA-approved for patients age 12 and older. It should be considered only for children over 12 years who have moderate-to-severe persistent asthma related to allergies and for adults who have severe asthma and allergies. Omalizumab is a biologic drug that targets and blocks the antibody immunoglobulin E (IgE), a chemical trigger of the inflammatory events associated with an allergic asthma attack.
Omalizumab is given by injection every 2 - 4 weeks. It is used only to treat patients whose symptoms are not controlled by inhaled corticosteroids.
Side Effects and Complications. About 1 in 1,000 patients who take omalizumab develop anaphylaxis (a life-threatening allergic reaction). Patients can develop anaphylaxis after any dose of omalizumab, even if they had no reaction to a first dose. Anaphylaxis may occur up to 24 hours after the dose is given.
Omalizumab should always be injected in a doctor’s office and health care providers should observe patients for at least 2 hours after an injection. Patients should also carry emergency self-treatment for anaphylaxis (such as an Epi-Pen) and know how to use it. With an Epi-Pen, or similar auto-injector device, patients can quickly give themselves a life-saving dose of epinephrine.
Anaphylaxis symptoms include:
The FDA is currently reviewing whether omalizumab may be associated with increased risk for heart and vascular problems (ischemic heart disease, arrhythmias, cardiomyopathy, heart failure, pulmonary hypertension, and blood clots).
Theophylline relaxes the muscles around the bronchioles and also stimulates breathing. Since the introduction of inhaled corticosteroids and long-acting beta2-agonists, theophylline is not used as often for asthma treatment. It may still be used in some circumstances, such as for treating nocturnal asthma. Theophylline is available in tablet, liquid, and injectable forms. Theophylline should not be used by people with peptic ulcers, and should be used with caution by anyone with heart disease, liver disease, high blood pressure, or seizure disorders.
If a child is taking theophylline on an ongoing basis, the doctor should monitor the drug level at the start of therapy and at regular intervals thereafter.
Children older than 6 months should receive an influenza vaccination every year. All children between 2 months and 2 years of age should receive a series of pneumococcal conjugate vaccinations, but children older than 2 years should receive one dose of the pneumococcal polysaccharide vaccine.
Patients with asthma and chronic allergic rhinitis may need daily medications. Patients with severe seasonal allergies may need to start taking medications a few weeks before the pollen season, and to continue them until the season is over.
Immunotherapy ("allergy shots") may help reduce asthma symptoms, and the use of asthma medications, in patients with known allergies. They may also help prevent the development of asthma in children with allergies. Immunotherapy poses some risk for severe allergic reactions, especially for children with poorly controlled asthma, so it is important that the doctor carefully evaluates the child’s asthma condition.
Children with obvious symptoms of reflux (heartburn) or children who have difficulty managing asthma may consider the following lifestyle changes:
Alternative therapies are widely used by children, adolescents, and adults with asthma. In one study, nearly half of asthma or allergy sufferers resorted to alternative treatments. To date, however, evidence does not support most alternative therapies, including high-dose vitamins, urine injections, homeopathic remedies, and most herbal remedies.
Relaxation and Stress-Reduction Techniques. Patients report benefits from many stress reduction and physical techniques, such as acupuncture, hypnosis, breathing relaxation techniques, the Alexander technique, massage therapy, and meditation. There have been very few well-conducted studies supporting their use, however.
Breathing Exercises. Breathing exercises may help improve patients’ quality of life even if they do not have a major impact on medication reduction.
Probiotics. Probiotics are beneficial microbes that some believe may help protect against allergies and asthma. Probiotics can be obtained in active yogurt cultures and in supplements, which are being studied for protection. However, evidence to date does not support efficacy in preventing or treating asthma.
Herbal Remedies. Few rigorous studies have evaluated herbal remedies for asthma. Manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been a number of reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.
The more allergies a child has, the more severe the asthma. Making lifestyle changes to reduce allergy attacks and other triggers is extremely important.
Asthma action plans create a written document for patients and parents to manage asthma during stable times and to more easily identify when asthma is worsening. Important components of a home program include:
Managing Asthma Exacerbations. Always refer to the written action plan from your doctors and nurses. Treatment approaches generally include:
Follow-up generally depends on the severity of asthma, how recently asthma was diagnosed, patient compliance, and whether recent changes in treatment were made.
House dust is a reservoir for pollen and dust mites. It is important to control household allergens and pollutants in the home.
Controlling for Dust. Spray furniture polish is very effective for reducing both dust and allergens. Air cleaners, filters for air conditioners, and vacuum cleaners with High Efficiency Particular Air (HEPA) filters can help remove particles and small allergens found indoors. Neither vacuuming nor the use of anti-mite carpet shampoo, however, is effective in removing mites in house dust. In fact, vacuuming stirs up both mites and cat allergens. If possible, avoid carpets and rugs.
Controlling Pets. For children who have an existing allergy to pets:
Bedding, Curtains, and Bedroom Environment.
Exterminating Pests (Cockroaches and Mice).
Reducing Humidity in the House. Living in a damp environment is counterproductive. Humidity levels should not exceed 30 - 50%.
Preventing Exposure to Cigarette and Cooking Smoke. Parents who smoke are strongly urged to quit. Studies indicate that exposure to second-hand smoke in the home increases the risk for asthma and asthma-related emergency room visits in children. Even smoky cooking can worsen asthma.
Avoiding Outdoor Allergens. The following are some recommendations for avoiding allergens outside:
Parents should make sure that their child’s school has a copy of the written asthma action plan. The plan should contain a list of medications the child takes (including which ones need to be taken during school hours), identified asthma triggers, and emergency contact numbers. Parents should also make sure that the school staff is trained in the steps to take in case of an asthma attack.
Asthma is no reason to avoid exercise. Historically, about 10% of Olympic athletes have asthma. Some studies indicate that long-term exercise may help control asthma and reduce hospitalization. Exercise can help control weight, which can help with asthma symptoms.
Encourage children with asthma to swim and play sports, such as baseball, that will be less difficult for them. Intense activities lasting less than 2 minutes, such as sprinting or competitive swimming, may cause fewer problems than longer-lasting exercises.
Young people who enjoy running should probably choose an indoor track to avoid pollutants. Swimming is excellent for people with asthma. Yoga, which uses stretching, breathing, and meditation techniques, may have particular benefits.
Patients should consult their doctors before starting any exercise program. Exercise-induced asthma (EIA) is a limited condition that has specific recommendations.
Hints for Reducing Exercise-Induced Asthma (EIA). EIA occurs only after exercise and is more likely to occur with regular paced activities in cold, dry air. The following are some suggestions for reducing its impact:
People with asthma should try to minimize their risk for respiratory tract infections. Washing hands is a very simple but effective preventive measure.
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