Asthma

Asthma is a disease in which inflammation of the airways restricts airflow in and out of the lungs. The word asthma comes from the Greek word for "panting." The panting and wheezing sound characteristic of asthma occur because of the restricted flow of air.

Normally, when you breathe in an irritant or are subjected to a stressor such as exercise, your airways relax and open, allowing the lungs to get rid of irritants or take in more air. In a person with asthma, muscles in the airways tighten and the lining of the air passages swells. The immune system gets involved, but instead of helping, it causes inflammation.

Asthma is a disease of both adults and children. In fact, asthma is the most common chronic childhood illness. About half of all cases of asthma develop before the age of 10. Many children with asthma also have allergies. While there is no cure for asthma, it can be controlled.

Signs and Symptoms

Most people with asthma have periodic attacks separated by symptom-free periods. Some asthmatics have chronic shortness of breath with episodes of increased shortness of breath. Asthma attacks can last minutes to days, and can become dangerous if the airflow becomes severely restricted.

The primary symptoms of asthma include:

• Shortness of breath
• Wheezing — usually begins suddenly; may be worse at night or early in the morning; aggravated by exposure to cold air, exercise, heartburn and relieved with the use of bronchodilators (drugs that open the airways; see Medications)
• Chest tightness
• Cough (dry or with sputum) — sometimes this is the only symptom

Call for emergency assistance if you have or are with someone having any of these serious symptoms:

• Extreme difficulty breathing or cessation of breathing
• Bluish color to the lips and face (called cyanosis)
• Severe anxiety
• Rapid pulse
• Profuse sweating
• Decreased level of consciousness (such as drowsiness or confusion)

Additional symptoms that may be associated with an asthma attack include:

• Flared nostrils
• Abnormal breathing pattern, in which exhalation takes more than twice as long as inhalation
• Use of the muscles between the ribs (called intercostals) to help with the increased work of breathing
• Coughing up blood (called hemoptysis)

Causes

Asthma is most likely caused by a combination of several factors. Experts suggest that in people who are susceptible (genetically predisposed), factors such as allergens (substances that commonly induce an allergic reaction), infections, dietary patterns, exercise, cigarette smoke, and stress can bring on an asthma attack.

Risk Factors

The following factors may increase the risk of developing asthma:

• Allergies — children with asthma often have allergies as well
• Family history of asthma or allergies
• Cigarette smoke, including second hand smoke from, for example, parents or a spouse
• Food allergies – a true food allergy, particularly one that induces asthma, is difficult to identify and, therefore, it is not clear exactly how frequently (or infrequently) this contributes to asthma; it seems to be more common in children than in adults and the responsible foods include eggs, milk, wheat, soy, peanuts, fish, shellfish, and sulfite food perservatives.
• Living in a Western or industrialized country – some experts believe that dietary habits (more processed foods, less fruits and vegetables), indoor living (resulting in overexposure to indoor allergens), energy-efficient homes (trapping allergenic dust mites inside), immunizations, and possibly, declining rates of breastfeeding contribute to the rising rates of asthma
• Urban living
• Gender — among younger children, asthma develops twice as frequently in boys as in girls, but after puberty it may be more common in girls
• Obesity – controversial; a recent study suggests that asthma is overdiagnosed among obese people

Triggers
Childhood asthma in particular can be triggered by almost all of the same things that trigger allergies, such as the following:

• Sensitivity to allergens in the air, such as dust, cockroach waste, animal dander, indoor and outdoor mold, pollens
• Respiratory infections
• Air pollutants, such as smoke from tobacco or a fireplace, aerosols, perfumes, fresh newsprint, diesel particles, sulfur dioxide, elevated ozone levels, and fumes from paint, cleaning products, and gas stoves
• Changes in the weather, especially in temperature (particularly cold) and humidity

Other triggers include:

• Behaviors that affect breathing (exercising, laughing, crying, yelling)
• Stress

Diagnosis

The symptoms of asthma can mimic several other conditions, and a doctor must take a thorough history to rule out other diseases. Questions will likely be asked about how and when symptoms occur, and if there is a family history of allergies and asthma or occupational exposure to chemicals. If asthma is suspected, tests (called pulmonary function tests) will probably be done to measure, among other things, the volume of your lungs and how much air you exhale. Other tests may include chest and sinus x-rays, blood tests, or allergy tests.

Preventive Care

Although there is no method guaranteed to prevent asthma, there are a number of measures parents can take to reduce their child's risk of developing asthma. These include:

• Exclusively breastfeeding for the first 3 to 6 months of life; this issue is controversial, however, with the most recent (and largest) study suggesting that breastfeeding for the first 6 months of life helps to protect the child up to age two, but may increase the risk once the child is older than two years.
• Delaying the introduction of solid food until age 6 months
• Manipulating the child's environment (not smoking during pregnancy or around infants, eliminating household allergens such as mites and cockroaches. For example, to reduce exposure to dust mites, encase mattresses and pillows in special covers that are impermeable to allergens; also, remove carpets from bedrooms.)

According to certain studies on adults, apples and selenium-rich food in the diet may protect against asthma, and moderate consumption of red wine may be associated with less severe asthma attacks. These foods are high in antioxidants (namely, flavonoids). It is too early to say definitively that these nutrients protect against asthma, however. Plus, it is important to note that in certain individuals, red wine may actually induce asthma symptoms if you have an allergy to sulfites, a food additive, or any other substance found in wine. Often, wine labels indicate if sulfites are present.

Key steps in preventing asthma attacks include identifying the allergens and the triggers that bring on or worsen your asthma symptoms and then working to eliminate or avoid them. Sometimes it takes exposure to more than one of these factors before an asthma episode is triggered. Keeping a diary to determine triggers may be helpful. Certain medication can help to prevent an attack due to triggers; in other words, if you know your triggers, you can anticipate when you might be exposed, and use your medication before that expected exposure.

The following conditions are common triggers for asthma. Reduce your chances of exposure to them by taking some common-sense steps:

• Viral infections (colds, flu, bronchitis, pneumonia) – stay away from people who you know are ill
• Sinusitis and allergic rhinitis (hay fever or year-round allergies) – avoid seasonal allergens by staying indoors in air conditioning as much as possible and eliminating indoor allergens; fewer allergy attacks generally means fewer cases of sinusitis and asthma
• Gastroesophageal reflux (heartburn) – avoid provoking foods, medication, and mealtime habits

Avoid the following altogether:

• If sensitive or allergic, aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs)
• Beta-blockers (such as acebutolol, atenolol, esmolol, labetalol, metoprolol, nadolol, pindolol, propranolol, and timolol) including those in eye medication
• If sensitive or allergic, processed potatoes, shrimp, dried fruit, beer, and wine – these often contain sulfite food preservatives

Allergy desensitization, if you have a known allergy, may decrease the number of asthma attacks you experience, diminish the intensity of each attack, and lower the amount of medication that you need. Desensitization includes regular injections of the allergen (substance causing the allergic reaction) given in increasing doses (each dose is slightly larger than the previous one). The aim of desensitization is to gradually accustom the immune system to the allergen so that it no longer reacts to that substance. This is done very slowly and carefully, starting with minute amounts of the substance, in a controlled setting (namely, your doctor's office). Talk to your doctor about whether desensitization is right for you.

Treatment Approach

Avoiding asthma attacks, reducing inflammation, and preventing lung damage are the primary goals of treatment. This requires educating yourself about asthma, working closely with your doctor to determine the severity of your asthma and to define a treatment plan, and following recommendations. Adjusting your environment as much as possible to prevent exposure to allergens or irritants and taking medication as prescribed are important for the successful control of asthma. Emergency medications are needed during an asthma attack, but daily monitoring of your asthma as well as a daily drug regimen are necessary in order to affect the course of the disease over the long term. Severe attacks of asthma require hospitalization for oxygen and medications that are given intravenously (that is, through a vein). Certain nutritional changes, particularly increasing the amount of omega-3 fatty acids in your diet and decreasing omega-6 fatty acids, and acupuncture may be useful adjuncts to conventional medical care to treat your asthma.

Lifestyle

• Quit smoking
• Lose weight if you are overweight and already have asthma; although the connection between obesity and asthma is not entirely understood, excess weight may put pressure on the lungs and trigger an inflammatory response.
• Monitor your asthma every day using a peak flow monitor (a portable device for measuring the highest exhalation flow, which is an indicator of lung volume). Working with your doctor to adjust medications according to readings may reduce hospitalizations and improve quality of life. Keep a diary of readings to show your doctor; together, you will establish your "personal best" reading. When your daily reading is between 50% and 80% of your personal best, this is considered a moderate asthma attack while values below 50% are severe. You should call your doctor if your peak flow reading falls below 80% and go to the hospital if it falls below 50%.
• Keep a diary of respiratory complaints – this may help determine triggers

Medications

Medications for asthma are prescribed for two different purposes. One is to halt an acute attack, and the other is to control inflammation and reduce lung damage over the long term.

Quick relief ("rescue" medications) – needed promptly during a moderate or severe asthma attack to open the airways. Such drugs are bronchodilators called short-acting beta-adrenergic agonists (beta2-agonists such as albuterol, isoproterenol, metaproterenol, pirbuterol, terbutaline, bitolterol, and levalbuterol). Other drugs used less commonly for acute attacks include theophylline and certain anticholinergic agents (like ipratropium bromide). Sometimes, steroids (such as prednisone, prednisolone, methylprednisolone, or hydrocortisone) are needed (either taken by mouth or, if in the hospital, given intravenously) for an acute asthma attack.

Long-term disease control is necessary for those taking short-acting beta2 agonists more than twice a week. The standard agents for these purposes are inhaled corticosteroids (including beclamethasone, budesonide, dexamethasone, flunisolide, fluticasone, and triamcinolone). Others include leukotriene-antagonists (namely, montelukast and zafirlukast), and cromolyn. For those with moderate to severe asthma, combinations of steroids and other medications (such as long-acting beta2 agonists or leukotriene-antagonists) are proving to be effective for both treating and preventing asthma attacks. The intention of long-term therapy is to reduce inflammation and prevent injury to the lungs.

Nutrition and Dietary Supplements

Studies indicate that people with asthma tend to have low levels of certain nutrients (for example, selenium and potassium) and that the Western diet (high in fast foods and low in fresh fruits and vegetables) has been associated with higher rates of asthma. In fact, fried foods and margarine may be particularly bad, especially in children. On the other hand, it has been suggested that adding onion, garlic, pungent spices, and antioxidants (such as foods rich in vitamin C, vitamin E, flavonoids, and beta-carotene) to the diet may help reduce symptoms.

Magnesium
Two large studies found that low dietary magnesium intake may be associated with risk of developing asthma in both children and adults. While studies suggest that intravenous magnesium (magnesium administered through a vein) can help treat acute attacks of asthma in children over age 6 and adults, it is not known if eating foods high in magnesium or taking magnesium supplements would make any difference in terms of asthma symptoms. During an acute asthma attack, a doctor will determine if intravenous magnesium is necessary and appropriate in a hospital setting.

N-acetylcysteine
A review of scientific studies suggests that N-acetylcysteine may help dissolve mucus and improve symptoms associated with asthma.

Omega-3 Fatty Acids
Preliminary research on adults with asthma suggests that an omega-3 fatty acid supplement (from perilla seed oil, which is rich in alpha-linolenic acid [ALA], an important omega-3 fatty acid) may reduce inflammation and improve lung function. ALA is also found in flaxseed and flaxseed oil. In addition, although controversial because of mixed reports from scientific studies, at least a few studies have found that fish oil supplements (rich in two other important omega-3 fatty acids, namely eicosopentaenoic acid [EPA] and docosahexaenoic acid [DHA]) may improve symptoms in children and adults with asthma. The studies on fish oil have only included a small number of people, however; therefore, definite conclusions cannot be drawn about whether fish oil supplements will help you or not if you have asthma.

One thing that can be said about omega-3 fatty acids is that if you enrich your diet with this type of essential fatty acid (from foods such as cold-water fish, flaxseeds, pumpkin seeds, and walnuts) and reduce your intake of omega-6 fatty acids (from foods like meat, egg yolks, and certain cooking oils), this is likely to help improve your symptoms.

Potassium
Data from several studies suggest that compared to diets with normal amounts of potassium, diets low in potassium are associated with poor lung function and even asthma in children. Improving dietary intake of potassium through foods such as fish, fruits, and vegetables may therefore be valuable for preventing or treating asthma. Adequate amounts of magnesium are needed to maintain normal levels of potassium. In addition, the drug theophylline (used sometimes for asthma) may deplete potassium, as can excessive intake of salt or caffeine in the diet.

Quercetin
Quercetin, which is a member of a group of antioxidants called flavonoids, inhibits the production and release of histamine and other allergic/inflammatory substances. Histamine is a substance that contributes to allergy symptoms such as a runny nose, watery eyes, and hives. Like other flavonoids, quercetin is a plant pigment responsible for colors seen in fruits and vegetables. Quercetin supplements often include bromelain (an enzyme found in pineapple), which is also an anti-inflammatory and anti-allergy agent. Bromelain increases the absorption of quercetin.

Selenium
Studies suggest that people with asthma tend to have low blood levels of selenium. In addition, a population-based study (studies that evaluate groups of people) suggested that eating selenium-rich foods may have a protective effect against asthma. Plus, taking selenium supplements may prove to be helpful as well. In a study of 24 people with asthma, for example, those who received selenium supplements for 14 weeks demonstrated a significant improvement in symptoms compared to those who received placebo. More studies, with larger numbers of people and lasting longer than 14 weeks, are needed to determine whether selenium supplementation is truly safe and effective for people with asthma.

Vitamin C
Although research is limited, there is some indication that vitamin C, particularly from fresh fruit in your diet, may be useful for treating allergy-related conditions such as asthma.

Other
Other supplements that may have benefit for asthma include:

• Coenzyme Q 10 (CoQ10) – if you have asthma, you may have low levels of this antioxidant in your blood. It is not known at this time, however, whether taking CoQ10 supplements will make any difference in your symptoms.
• Lactobacillus acidophilus – there is some evidence that this "good" organism (called a probiotic), which is found naturally in the gut, may reduce the risk of developing an allergic reaction, including asthma. In fact, some early evidence suggests that if mothers who have at least one relative with asthma, or some other allergy-related illness, take this probiotic while pregnant and breastfeeding, their babies may be less likely to develop asthma.
• Lycopene and beta-carotene – preliminary data suggests that each of these two antioxidants may prove useful for preventing exercise induced asthma symptoms when taken daily.
• Vitamin B6 – may be needed if you are taking theophylline because this medication can lower blood levels of this nutrient.

Herbs

Herbs, like medications, may produce side effects or interact with other substances including drugs. They should, therefore, be used with caution and only under the guidance of a professionally trained and qualified herbalist.

Flaxseed
Preliminary research suggests that omega-3 fatty acids (including flaxseeds) may decrease inflammation and improve lung function in adults with asthma.

French Maritime Pine (Pinus pinaster)
A 2002 review of studies on a standardized extract from French maritime pine bark suggests that the extract may reduce symptoms and improve lung function in people with asthma.

Lobelia (Lobelia inflata)
Lobelia has a long history of use. It is considered an effective expectorant, meaning that it helps clear mucus from the respiratory tract. Although there are few thorough studies on the safety and effectiveness of lobelia, some herbalists today incorporate lobelia into a comprehensive treatment plan for asthma. Lobelia is a potentially toxic herb, but is considered relatively safe when used in combination with other herbs that affect the respiratory system. Lobelia use should only be considered with the guidance of a qualified healthcare practitioner.

Other
Herbalists may select from the following herbs that have been used traditionally to treat asthma:

• Feverfew (Tanacetum parthenium)
• Ginkgo (Ginkgo biloba)
• Goldenrod (Solidago virgaurea)
• Marshmallow (Althaea officinalis)
• Red Clover (Trifolium pretense)
• Wild Yam (Dioscorea villosa)

Also, aloe (Aloe vera) is under investigation for its possible use in helping to treat asthma.

Acupuncture

Acupuncture has shown potential as an effective treatment for asthma, according to a 1997 Consensus Statement by the National Institutes of Health. It is important, however, that if acupuncture is used for asthma, it be used in addition to (rather than as a replacement for) conventional medicine. One study found that acupuncture improved the immune response of people taking anti-asthma medication compared to those who did not receive acupuncture.

In addition to needling, acupuncturists may also use an herb-burning technique called moxibustion (a technique in which the herb mugwort [Artemesia vulgaris] is burned and the heat is held over specific acupuncture points) when treating you for asthma. Some acupuncturists may also perform a special type of massage therapy (called tui na), offer lifestyle counseling, provide instruction on specific breathing exercises, and prescribe herbal remedies.

Chiropractic

Chiropractors report that some people with asthma benefit from spinal manipulation, but the results of scientific studies have been somewhat mixed. A recent review of scientific literature, for example, concluded that "there is insufficient evidence to support or refute the use of manual therapy for patients with asthma." Among the trials reviewed, two studies compared spinal manipulation to sham manipulation in people with asthma. Sham manipulation refers to maneuvers that shift soft tissues surrounding the bone but do not actually adjust the spine or joint. Participants in both the spinal manipulation group and the sham group reported similar improvements in asthma symptoms, suggesting that spinal manipulation may be no more effective than sham therapy. In another study involving 81 children with asthma, chiropractic care was associated with a 45% reduction in the number of asthma "attacks." Thirty percent of the children in the study experienced such an improvement in symptoms that they were able to decrease their asthma medication dosage by 66% while receiving chiropractic care.

In another small study, 36 children with asthma who received chiropractic care in addition to their usual medical management reported improved symptoms after three months. Chiropractic therapy should be used in addition to (never as a substitute for) your regular medical treatment for asthma.

Massage and Physical Therapy

A few studies of small numbers of children and adults with asthma have suggested that massage therapy may reduce anxiety associated with asthma, improve symptoms, and even improve lung function. Given the limited scope of these studies, however, more research is needed to understand the relationship between massage therapy and asthma, beyond the ability of this technique to reduce stress and induce relaxation.

Homeopathy

Although very few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of asthma based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type. A constitutional type is defined as a person's physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

• Arsenicum album — for asthma that generally worsens between midnight and 2 am and is accompanied by restlessness, anxiety, chills, and thirst
• Ipecacuanha — for those with asthma, particularly children, who have significant tightness in the chest, a chronic cough with lots of phlegm that may lead to vomiting, and worsening of symptoms in hot, humid weather
• Pulsatilla — for asthma with yellow or greenish phlegm that gets worse in the evening, in warm, stuffy rooms, or after consuming rich, fatty foods; this remedy is most appropriate for adults or children who are tearful and clingy or sweet and affectionate
• Sambucus — for asthma that awakens a person at night with a sensation of suffocation; symptoms worsen when the person is lying down

Mind/Body Medicine

Asthma can be made worse by stress, anxiety, and sadness. In the other direction, if you have asthma, it is not uncommon to feel anxious or depressed. Incorporating stress management techniques into daily life may help reduce symptoms. Experts suggest that the following may prove helpful for people with asthma:

• Education about asthma
• Hypnosis – this may be especially useful in children because they are more easily hypnotized and can readily learn the technique.
• Yoga – in addition to general relaxation and reduction of stress, several studies of people with asthma have suggested that lung function and exercise capacity may improve with the regular practice of yoga and that, eventually, the amount of medication taken may be reduced. The yoga that has been practiced in most of these studies has involved breathing exercises (called pranayama), stretches (known as postures in yoga), and meditation. Additional research would be helpful on larger numbers of people to understand more about the effects of yoga on asthma. Medication should never be adjusted without discussing this with your doctor.
• Biofeedback
• Joining a support group

Traditional Chinese Medicine

The practice of Traditional Chinese Medicine often involves taking herbs, applying acupuncture, and making lifestyle changes. Such changes may include doing movement exercises that encourage particular breathing exercises and meditation. Examples of such exercises include tai chi and qi (pronounced "chee") gong. In a review of the use of qi gong for asthma, the authors concluded that combining a regular practice of qi gong with medication may allow you to reduce your drug dose, your need for sick leave from work or school, the length of time that you spend in the hospital, and the overall cost of your asthma therapy. (Note that your medication dosage should never be adjusted without the discussion and consent of your doctor.)

A few herbs that a Traditional Chinese medical specialist might recommend include:

Asian Ginseng
In Chinese medical practice, Asian ginseng (Panax ginseng) is often a standard part of therapy. One test tube study performed in a laboratory suggests that the reason this may work is because ginsenoside, an active ingredient of ginseng, relaxes bronchial smooth muscle cells; these are the cells that line the airway and, when restricted, cause diminished air flow and a feeling of shortness of breath.

Ephedra
Ephedra (Ephedra sinica), also called ma huang, has been used in Traditional Chinese Medicine for more than 5,000 years. It is sometimes used to treat asthma, and synthetic ephedrine compounds, such as pseudoephedrine, are widely used in over-the-counter cold remedies. However, ephedra and its derivatives are potentially dangerous and addictive. Take only under the close guidance and supervision of an appropriately trained specialist.

Japanese Herbal Medicine
Saiboku-to (TJ-96) is an herbal complex approved by the Japanese government for the treatment of asthma. In one Western study, people with asthma who took the formula for 4 weeks had significantly improved symptoms. This study also found that saiboku-to has anti-inflammatory effects.

Other Considerations

Exercise
Although exercise can be a trigger for asthma in some people, with appropriate treatment and monitoring of the condition, exercise, even vigorous exercise, is possible. In fact, many world-class athletes have asthma. Consult with your doctor before starting an exercise program, and carry an inhaler at all times.

Pregnancy
Women who are pregnant or breastfeeding should avoid the following:

• Ephedra and ephedra alkaloids such as ephedrine
• Goldenrod
• Lobelia
• Red Clover

Warnings and Precautions

Flaxseed may interfere with the absorption of medication. Avoid taking it at the same time of day as medications and other supplements:

You should never take more than 20 mg of lobelia per day. People with high blood pressure, heart disease, tobacco sensitivity, paralysis, seizure disorder, and acute shortness of breath as well as those recovering from shock should not take lobelia.

Long-term treatment with theophylline for asthma may reduce blood levels of vitamin B6.

Prognosis and Complications

Fourteen million Americans have asthma. People with asthma can live normal, active lives. The condition requires self-care and monitoring over the long term, as well as close contact with your doctor. Most people with asthma have periodic attacks separated by symptom-free periods. Some asthmatics have chronic shortness of breath with episodes of increased shortness of breath. Asthma attacks can last minutes to days, and can be dangerous, even life threatening, if the airflow becomes severely restricted. With that said, death from asthma is extremely uncommon, especially if the proper treatment recommendations are followed, including use of inhaled steroids which can reduce the risk of dying from asthma by ninety percent. Poor mood can adversely affect self-care. Paying attention to mood and life stress and having adequate emotional support will help to ensure that self-care is consistent. Those who have occupation-related asthma may be able to reduce symptoms by wearing a protective respiratory mask.

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