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All about asthma types of asthma bronchial asthma exercise induced asthma adult-onset asthma status asthmaticus causes of asthma asthma triggers asthma and allergy asthma attack asthma in children asthma and pregnancy asthma in adults and older people complications of asthma symptoms of asthma warning signs of asthma asthma diagnosis asthma treatments asthma relief (rescue) medications asthma long-term control medications asthma inhalers asthma nebulizers control acute asthma attacks management of chronic asthma symptoms asthma relievers asthma preventers childhood asthma cures treatment for asthma in the elderly asthma prevention

What types of asthma are there?

Asthma is sometimes classified in various ways. Often, these "types of asthma" describe the triggers that may cause an asthma episode (or asthma attack) or the things that make asthma worse in certain individuals. There are various different types of asthma, some of which are difficult to readily diagnose. Further complicating accurate diagnosis is that, at times,

and in certain individuals, there are very specific symptoms (or patterns of symptoms) unique to any one person.

Child-onset asthma: When asthma does begin in childhood, it often does so in a child who is likely, for genetic reasons, to become sensitized to common "allergens" in the environment (atopic person). When these children are exposed to house-dust mites, animal proteins, fungi, or other potential allergens, they produce a type of antibody that is intended to engulf and destroy the foreign materials. This has the effect of making the airway cells sensitive to particular materials. Further exposure can lead rapidly to an asthmatic response. This condition of atopy is present in at least one-third and as many as half of the general population. When an infant or young child wheezes during viral infections, the presence of allergy (in the child itself or a close relative) is a clue that asthma may well continue throughout childhood.

Adult-onset asthma: Adult-onset asthma develops after age 20. It is less common than asthma in children, and it affects more women than men. Allergenic materials may also play a role when adults become asthmatic. Asthma can actually start at any age and in a wide variety of situations. Although less common than asthma in children, adult-onset asthma can also be triggered by allergies. Between 30 percent and 50 percent of all adult cases are associated with allergies, but often allergic exposures don't seem to be the most important, driving factors. This nonallergic adult-onset asthma is sometimes called "intrinsic." Many adults who are not allergic do have such conditions as sinusitis or nasal polyps, or they may be sensitive to aspirin and related drugs. Another major source of adult asthma is exposure at work to animal products, certain forms of plastic, wood dust, or metals.

Exercise-induced asthma: Shortness of breath and/or wheezing occurring after strenuous exercise is called exercise-induced asthma. Although this phenomenon happens in up to 80% of people with recognized asthma, it frequently takes place as an isolated event without any other symptoms of asthma at any other time. This complicates any diagnosis of asthma as an underlying cause because frequently this form of asthma is confused with poor physical conditioning or possible heart problems. Nevertheless, asthma should always be suspected as a possible cause of exercise-induced wheezing or shortness of breath, especially when the person is otherwise healthy. Exercise-induced asthma involves symptoms that occur about 5-20 minutes after beginning an exercise that involves breathing through the mouth. Sports and games that require continuous activity or that are played in cold weather (for example, long-distance running, hockey, soccer, and cross-country skiing) are the most likely to trigger an asthma attack. Other physical exertions that can trigger an attack include laughing, crying, and hyperventilating.

Cough-variant asthma: Coughing can occur alone, without the other symptoms of asthma that are usually present and recognized by the physician or patient. Cough variant asthma causes great difficulty for the physician to accurately diagnose the true underlying cause of the cough as being asthma because it can be easily confused with other conditions, such as chronic bronchitis and post nasal drip due to hay fever or sinus disease. Coughing can occur day or night. Nighttime coughing is most disruptive, interfering with sleep.

Occupational asthma: Occupational asthma occurs in response to a trigger in the workplace. Triggers include contaminants in the air, such as smoke, chemicals, vapors (gases), fumes, dust, or other particles; respiratory infections, such as colds and flu (viruses); allergens in the air, such as molds, animal dander, and pollen; extremes of temperature or humidity; and emotional excitement or stress. In occupational asthma, the trigger is a substance or condition in the workplace that causes asthma symptoms. Most of these substances and conditions are very common and are not normally considered hazardous. Although these substances and conditions can be encountered in almost any workplace, occupational asthma is most common in workers in the following industries and jobs. In most people with occupational asthma, the symptoms appear a short time after beginning work and subside after leaving work.

Nocturnal asthma: Nocturnal asthma occurs between midnight and 8 am. It is triggered by allergens in the home such as dust and pet dander or is caused by sinus conditions. Nocturnal or nighttime asthma may occur without any daytime symptoms recognized by the patient. This is called "nocturnal asthma." The patient may have wheezing or short breath when lying down or may not notice these symptoms until awoken by them in the middle of the night, usually between 2 and 4am. Nocturnal asthma may occur only once in a while or frequently during the week. Nighttime symptoms may also be a common problem in people who have daytime asthma as well, but then its true nature is more readily recognized. When there are no daytime symptoms to suggest asthma is an underlying cause of the nighttime cough, this type of asthma will be more difficult to recognize and usually delay proper therapy. The cause (or causes) of this phenomenon is unknown, although many possibilities are under investigation.

Steroid-resistant asthma (severe Asthma): While the majority of patients respond to regular inhaled glucocorticoid (steroid) therapy, some are steroid resistant. Airway inflammation and immune activation plays an important role inchronic asthma. Current guidelines of asthma therapy have therefore focused on the use of anti-inflammatory therapy, particularly inhaled glucocorticoids (GCs). One of the major mechanisms by which glucocorticoids act in asthma is by reducing airway inflammation and immune activation. However, patients with steroid resistant asthma have higher levels of immune activation in their airways than do patients with steroid sensitive (SS) asthma. Furthermore, glucocorticoids do not reduce the eosinophilia or T cell activation found in steroid resistant asthmatics. This persistent immune activation is associated with high levels of IL-2, IL-4 and IL-5 in the airways of these patients.

More information on asthma

What is asthma? - Asthma is a chronic inflammatory respiratory disease characterized by periodic attacks of wheezing, shortness of breath, and a tight feeling in the chest.
What types of asthma are there? - Types of asthma include child-onset asthma, adult-onset asthma, exercise-induced asthma, cough-variant asthma, occupational asthma, nocturnal asthma.
What's bronchial asthma? - Bronchial asthma is a disease of the lungs in which an obstructive ventilation disturbance of the respiratory passages evokes a feeling of shortness of breath.
What is exercise-induced asthma? - Exercise-induced asthma is a form of asthma that some people have during or after physical activity. Exercise-induced asthma is common.
What is adult-onset asthma? - Adult onset asthma generally is the onset of asthma for the first time in someone of middle age or older. Adult-onset asthma develops after age 20.
What is status asthmaticus? - Status asthmaticus is a severe asthma episode that does not respond to standard treatment. Status asthmaticus is caused by severe bronchospasm.
What causes asthma? - Asthma is caused by inhaling an allergen that sets off the chain of biochemical and tissue changes leading to airway inflammation, bronchoconstriction, and wheezing.
What're the asthma triggers? - Many risk factors have been linked to triggering asthma attacks. There are two basic types of asthma triggers, allergic triggers, non-allergic triggers.
Asthma and allergy - Asthma attacks (worsening of asthma symptoms) can be triggered by allergies. Allergy is the leading cause of asthma.
What is an asthma attack? - An asthma attack occurs when the small and medium-sized airways become inflamed and constricted after being exposed to a trigger.
Asthma in children - Asthma is the most common chronic condition of childhood. Asthma symptoms can interfere with many school activities for children.
Asthma and pregnancy - During pregnancy, asthma or asthma episodes will become worse for an estimated one-third of pregnant women, particularly women who have severe asthma.
Asthma in adults and older people - Identifying asthma in the elderly can be difficult because asthma symptoms can be confused with symptoms of heart or lung diseases.
What're the complications of asthma? - Uncontrolled asthma in pregnant women puts them at higher risk for complications that can include early labor, hypertension, gestational diabetes.
What are the symptoms of asthma? - The symptoms of asthma include labored breathing, constriction of the chest, coughing and gasping usually brought on by allergies.
What're the warning signs of asthma? - Most people with asthma have warning signs before symptoms appear. There are many warning signs of an asthma episode.
How is asthma diagnosed? - The diagnosis of asthma is made on the basis of typical symptoms and signs. Positive allergy tests support a diagnosis of asthma.
What're the treatments for asthma? - Treatment of asthma is aimed at avoiding known allergens and respiratory irritants and controlling symptoms and airway inflammation through medication.
What quick relief (rescue) medications cure asthma? - Short-acting beta-agonists are the most commonly used asthma rescue medications. Anticholinergics are another class of asthma drugs.
Long-term asthma control medications - Combinations of steroids and other medications are effective for both treating and preventing asthma attacks in patients with moderate to severe asthma.
What're asthma inhalers? - Most asthma drugs are inhaled using special devices or nebulizers. Two common types include dry powder asthma inhalers and metered-dose asthma inhalers.
What're asthma nebulizers? - Asthma nebulizers can be used with all classes of inhaled medications but are most commonly used with short-acting beta2 agonists and ipratropium bromide.
How to control acute asthma attacks? - Acute asthma is an acute exacerbation of wheezing, unresponsive to usually effective therapy and necessitating care in an emergency room or hospital ward.
How to manage chronic asthma symptoms? - The aims of management are to recognize asthma, to abolish symptoms, to restore normal or best possible long term airway function.
What asthma relievers are available? - Asthma reliever is a drug that provides relief from asthma symptoms and is the most commonly used asthma medication.
What asthma preventers are available? - Asthma preventers are to be used twice a day regardless of whether your child has symptoms of asthma.
What's the treatment for childhood asthma? - The goals of asthma therapy are to prevent child from having chronic and troublesome symptoms, to maintain child's lung function.
What's the treatment for asthma in the elderly? - Diagnosis and treatment of asthma can be more complicated in people age 65 and older than in those who are younger.
What can be done to prevent asthma? - Avoiding known allergens and respiratory irritants can reduce asthma symptoms. People with asthma should minimize risk for respiratory tract infections.
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