Asthma

What is Asthma?
Asthma is a disease affecting the airways that carry air to and from the lungs. People who suffer from this chronic condition (long-lasting or recurrent) are said to be asthmatic.

The inside walls of an asthmatic's airways are swollen or inflamed. This swelling or inflammation makes the airways extremely sensitive to irritations and increases susceptibility to an allergic reaction.
As inflammation causes the airways to become narrower, less air can pass through them, both to and from the lungs. Symptoms of the narrowing include wheezing (a hissing sound while breathing), chest tightness, breathing problems, and coughing. Asthmatics usually experience these symptoms most frequently during the night and the early morning.
Types of Asthma
Child-Onset Asthma

Asthma that begins during childhood is called child-onset asthma. This type of asthma happens because a child becomes sensitized to common allergens in the environment - most likely due to genetic reasons. The child is atopic - a genetically determined state of hypersensitivity to environmental allergens.
Allergens are any substances that the body will treat as a foreign body, triggering an immune response. These vary widely between individuals and often include animal proteins, fungi, pollen, house-dust mites and some kind of dust. The airway cells are sensitive to particular materials making an asthmatic response more likely if the child is exposed to a certain amount of an allergen.
Adult-Onset Asthma
This term is used when a person develops asthma after reaching 20 years of age. Adult-onset asthma affects women more than men, and it is also much less common than child-onset asthma.
It can also be triggered by some allergic material or an allergy. It is estimated that up to perhaps 50% of adult-onset asthmas are linked to allergies. However, a substantial proportion of adult-onset asthma does not seem to be triggered by exposure to allergen(s); this is called non-allergic adult-onset asthma. This non-allergic type of adult onset asthma is also known as intrinsic asthma. Exposure to a particle or chemical in certain plastics, metals, medications, or wood dust can also be a cause of adult-onset asthma.
Exercise-Induced Asthma
If a person coughs wheezes or feels out of breath during or after exercise, the person could be suffering from exercise-induced asthma. Obviously, the level of fitness is also a factor - a person who is unfit and runs fast for ten minutes is going to be out of breath. However, if coughing, wheezing or panting does not make sense, this could be an indication of exercise-induced asthma.
Cough-Induced Asthma
Cough-induced asthma is one of the most difficult asthmas to diagnose. The doctor has to eliminate other possibilities, such as chronic bronchitis, post nasal drip due to hay fever, or sinus disease. In this case the coughing can occur alone, without other asthma-type symptoms being present. The coughing can happen at any time of day or night. If it happens at night it can disrupt sleep.
Occupational Asthma
This type of asthma is triggered by something in the patient's place of work. Factors such as chemicals, vapors, gases, smoke, dust, fumes, or other particles can trigger asthma. It can also be caused by a virus (flu), molds, animal products, pollen, humidity and temperature. Another trigger may be stress. Occupational asthma tends to occur soon after the patients start a new job and disappears not long after leaving that job.
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. The patient may have wheezing or short breath when lying down and may not notice these symptoms until awoken by them in the middle of the night - usually between 2 and 4 AM.
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 play an important role in chronic asthma. Current guidelines of asthma therapy have therefore focused on the use of anti-inflammatory therapy, particularly inhaled glucocorticoids (GCs). By reducing airway inflammation and immune activation, glucocorticoids are used to treat asthma. However, patients with steroid resistant asthma have higher levels of immune activation in their airways than do patients with steroid sensitive (SS) asthma.

What Causes Asthma?

Children at Risk
Asthma is the most common chronic disease among children - especially children who have low birth weight, are exposed to tobacco smoke, are black, and are raised in a low-income environment. Most children first present symptoms around 5 years of age, generally beginning as frequent episodes of wheezing with respiratory infections. Additional risk factors for children include having allergies, the allergic skin condition eczema, or parents with asthma.
Young boys are more likely to develop asthma than young girls, but this trend reverses during adulthood. Researchers hypothesize that this is due to the smaller size of a young male's airway compared to a young female's airway, leading to a higher risk of wheezing after a viral infection.
Allergies
Almost all asthma sufferers have allergies. In fact, over 25% of people who have hay fever (allergic rhinitis) also develop asthma. Allergic reactions triggered by antibodies in the blood often lead to the airway inflammation that is associated with asthma.
Common sources of indoor allergens include animal proteins (mostly cat and dog allergens), dust mites, cockroaches, and fungi. It is possible that the push towards energy-efficient homes has increased exposure to these causes of asthma.
Tobacco Smoke
Tobacco smoke has been linked to a higher risk of asthma as well as a higher risk of death due to asthma, wheezing, and respiratory infections. In addition, children of mothers who smoke - and other people exposed to second-hand smoke - have a higher risk of asthma prevalence. Adolescent smoking has also been associated with increases in asthma risk.
Environmental Factors
Allergic reactions and asthma symptoms are often the result of indoor air pollution from mold or noxious fumes from household cleaners and paints. Other indoor environmental factors associated with asthma include nitrogen oxide from gas stoves. In fact, people who cook with gas are more likely to have symptoms such as wheezing, breathlessness, asthma attacks, and hay fever.

Pollution, sulfur dioxide, nitrogen oxide, ozone, cold temperatures, and high humidity have all been shown to trigger asthma in some individuals.
During periods of heavy air pollution, there tend to be increases in asthma symptoms and hospital admissions. Smoggy conditions release the destructive ingredient known as ozone, causing coughing, shortness of breath, and even chest pain. These same conditions emit sulfur dioxide, which also results in asthma attacks by constricting airways.
Weather changes have also been known to stimulate asthma attacks. Cold air can lead to airway congestion, bronchoconstriction (airways constriction), secretions, and decreased mucociliary clearance (another type of airway inefficiency). In some populations, humidity causes breathing difficulties as well.
Obesity
Overweight adults are more likely to have asthma compared to adults who are not overweight. Obese adults have twice the risk of asthma. According to some researchers, the risk may be greater for nonallergic asthma than allergic asthma.
Stress
People who undergo stress have higher asthma rates. Part of this may be explained by increases in asthma-related behaviors such as smoking that are encouraged by stress. However, recent research has suggested that the immune system is modified by stress as well.
Genes

Genes linked to asthma also play roles in managing the immune system and inflammation. There have not, however, been consistent results from genetic studies across populations - so further investigations are required to figure out the complex interactions that cause asthma.
Mom and Dad may be partially to blame for asthma, since three-fifths of all asthma cases are hereditary. The Centers for Disease Control (USA) say that having a parent with asthma increases a person's risk by three to six times.
Atopy
Atopy - such as eczema (atopic dermatitis), allergic rhinitis (hay fever), allergic conjunctivitis (an eye condition) - is a general class of allergic hypersensitivity that affects different parts of the body that do not come in contact with allergens. Atopy is a risk factor for developing asthma.
Some 40% to 50% of children with atopic dermatitis also develop asthma, and it is probable that children with atopic dermatitis have more severe and persistent asthma as adults.

Treatment for Asthma

Asthma is not so much "treated" as it is "controlled". As a chronic, long-term disease, there is no cure. However, there are tools and medicines to help asthmatics control asthma as well as benchmarks to gauge their progress.
The Peak Flow Meter
A peak flow meter is a simple, small, hand-held tool that can help maintain control of asthma by providing a measurement of how well air moves out of the lungs.
After blowing into the device, the meter reveals the peak flow number. A physician will indicate how often to test as well as how to interpret the result to determine the amount of medication to take. Some people record scores every morning while others use the peak flow meter intermittently.
Good Control
Good control means avoiding things that trigger asthma or asthma symptoms such as allergens. This may mean limiting time spent outdoors when pollen levels or air pollution levels are highest and limiting contact with animals. Asthma linked to allergies can also be suppressed by getting the necessary allergy shots.
Preventive Checkups
Part of good asthma control is seeing a doctor every 2 to 6 weeks for regular checkups until it is under control. Then checkups may be reduced to once a month or twice a year.
It is a good habit to keep track of asthma symptoms and attacks and diagnostic numbers such as the peak flow measurement. Doctors and nurses will ask about these and about daily activities in order to gauge the status of asthma control.
Medicine

Medication for asthma is broadly categorized as either quick-relief medicine or long-term control medicine. Reducing airway inflammation and preventing asthma symptoms is the goal of long-term control medicines, where as immediate relief of asthma symptoms is the goal of quick-relief or "rescue" medicines.
Medications can be ingested in pill form, but most are powders or mists taken orally using a device known as an inhaler. Inhalers permit medicines to travel efficiently through the airways to the lungs.
Inhaler
Medication may also be administered using a nebulizer, providing a larger, continuous dose. Nebulizers vaporize a dose of medication in a saline solution into a steady stream of foggy vapor that is inhaled by the patient.
Long-Term Control
Long-term control medicines are taken every day and are designed to prevent asthma symptom such as airway inflammation. Inhaled corticosteroids are the most effective long-term control medicine - the best at relieving airway inflammation and swelling. They are usually taken daily to greatly reduce the inflammation that initiates the chain reaction of the asthma attack.
There are other long-term control medicines available that doctors may prescribe. Most of them are taken by mouth and are designed to open the airways and prevent airway inflammation.
Quick-Relief Medicines
Quick-relief medicines relieve asthma symptoms when they occur. The most common of these are inhaled short-acting B2-agonists - bronchodilators that quickly relax tight muscles around the airways, allowing air to flow through them.

Living with Asthma - Conclusion
Asthma should not stop anyone from leading an active, healthy life. The chronic condition requires proper long-term care, active management, and adherence to an asthma action plan. Asthma can be a stressful condition to manage, and stress can even trigger asthma attacks. Asthmatics should strive to reduce stress as much as possible and learn to cope with the challenges and frustrations of living with asthma in a positive way.

Day-to-day living may be more manageable if one can find support from other people who are also living with asthma. Online forums also exist for people to share experiences, opinions, and frustrations. Support is equally important for children and teens with asthma.
An important part of managing asthma is adopting a healthy lifestyle. Asthmatics should eat a healthy diet rich in fruits and vegetables and low in fats and sugars, get plenty of rest, exercise regularly, work on managing stress, and, of course, should not smoke.
Identifying and avoiding asthma triggers will help to maintain an active and healthy lifestyle with asthma. Asthmatics should start to feel much better if their home is a trigger-free place. Sometimes, relocation is advised since some areas of the country are more likely to have asthma triggers than other areas.
Additionally, asthmatics should get regular treatment for any conditions that may interfere with their asthma management. Keeping all aspects of asthma under control is the key to living with it successfully.