Tuesday, June 20, 2006

The Simplest Asthma Solution

During the Democratic convention the Reverend Al Sharpton quoted a shocking statistic: One third of the children in Harlem suffer from asthma. This shouldn’t be completely surprising since asthma cases have been consistently increasing over the years, especially in the cities, escalating recently during the rollback of some key environmental laws, but it is a trend we must turn back.

While parents have only limited control over the environment where they raise their children, there is a personal environmental decision they can make that may dramatically reduce the symptoms their children experience. It all comes down to detergent, and not just any detergent. It is the detergent that they use to wash their children’s clothes and sheets. The biggest selling detergents in the United States contain large amounts of irritating phosphates, which are not only a major irritant to the skin and respiratory system, but a source of serious pollution, and a component in global warming.

If you are wondering if your laundry detergent contains phosphates just read the label, it is listed there. In most industrialized countries phosphate detergents are outlawed for good reason, but in the United States the chemical industry has a strong lobby and cheap phosphates help manufacturers keep their costs low, so their use continues. The next time you walk though the laundry detergent section of your supermarket, take a deep breath and notice how much the smell irritates your nose and lungs.

What kinds of detergent contain low, or no phosphates? Baby detergent! No mother would dream of washing their newborn’s clothes and sheets in the family’s powdered detergent! That would give their baby’s delicate skin rashes, not to mention an increase in crying and crankiness. There are many readily available natural detergents that are phosphate-free and it’s worth the time to find them.

We have noticed tremendous improvements for both children and adults when their clothes and sheets are consistently washed in a phosphate-free detergent. By itself this change may not alleviate all of the symptoms of asthma and those related skin rashes, but it clearly removes an insidious irritant from the equation.

It might be helpful to explain why this simple change is so effective. Testing in Europe shows that, while sleeping, people are between two thousand and ten thousand times more sensitive to chemical and electromagnetic pollution than while they are awake. When a child’s pajamas are washed with a chemical irritant and they sleep on bedclothes containing those same toxins, their immune system is challenged nightly, during a time when they are most vulnerable. Their body’s nutritional reserves are consumed in that battle and they are less able to defend themselves from the pollutants they encounter during their day. Asthma and allergies are not produced by a single irritant, but by an accumulation of minor irritants that eventually overwhelm the body’s ability to adapt. It is not a huge leap to imagine that removing a respiratory irritant from the sleeping environment, where a person spends one third of their time, is going to produce an improvement in a child’s ability to breathe.

Drs. Ralph & Lahni DeAmicis are Naturopathic Physicians. Their educational program, The 10 Minute Herbalist, seeks to put the knowledge of everyday good health into everyone’s hands. Information about their program and publications is available at www.SpaceAndTime.com.

Sunday, November 06, 2005

Natural Help for Asthma

Natural Help for Asthma
By Stewart Hare

Asthma is a long term inflammatory disease that affects the lungs and respiration in which inflammation and spasms of the bronchial passages slows the flow of air to and from the lungs due to increase amounts of mucus, the exact cause of asthma is unknown but it has been linked to an abnormal immune response in which attacks are thought to be brought on by stress, allergies, changes in environmental conditions, viral infections, emotions, exercise, food additives and airborne irritants. Individuals being affected by asthma have risen slowly over the past 20 years and it is thought that environmental pollution is the main cause with exposure to a wide variety of chemicals and typically exposure to cotton dust, flour dust, animal fur and smoke in a working environment. The typical symptoms of asthma are tightness in the chest, shortness of breath, wheezing and coughing.

As well as using a preventer inhaler to dampen down the symptoms of asthma other methods can be used to help the condition. Try to avoid those elements that trigger an attack, avoid dust, smoke, mould, animal dander, pollen, chemicals and food additives, keep to a vegan type diet with plenty of fruit and vegetables, avoid sugar, salt, caffeine, chlorinated tap water, avoid food additives such as sulphites, tartrazine, sodium benzoate, and natural salicylates and increase oily fish in the diet such as salmon, trout, herring, mackerel, sardines and tuna. Suffers of asthma may find it beneficial to also try acupuncture and the set of breathing techniques called Buteyko.

The following supplements may help if you are suffering from asthma.

Multivitamins and minerals

Vitamin C

Evening primrose oil

Borage oil

Fish oil

Flaxseed oil

Hemp seed oil

Selenium

Magnesium

Vitamin B6

Boswellia

Vitamin E

Red clover

Bromelain

Oregano

Liquorice

Green tea

Quercetin

Lycopene

Extract of New Zealand green-lipped mussel

Molybdenum

Vitamin B12

Stewart Hare C.H.Ed Dip NutTh
Advice for a healthier natural life

Wednesday, October 26, 2005

Asthma Steroid Pharmacogenetics

Asthma Steroid Pharmacogenetics



A Study Strategy to Identify Replicated Treatment Responses

Scott T. Weiss, Stephen L. Lake, Eric S. Silverman, Edwin K. Silverman, Brent Richter, Jeffrey M. Drazen and Kelan G. Tantisira

Channing Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston; and Pulmonary Division, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts

Correspondence and requests for reprints should be addressed to Scott T. Weiss, M.D., M.S., Director, Respiratory, Genetic, and Environmental Epidemiology, Channing Laboratory, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115. E-mail: restw@channing.harvard.edu

Asthma treatment with inhaled steroids demonstrates significant between-person variability. Genetic variation could contribute to this response to inhaled glucocorticosteroids. Difficulties in performing genetic association studies are well known. We designed a test and validation strategy to assess steroid pathway candidate genes. One hundred thirty-one single nucleotide polymorphisms in 14 candidate genes in the steroid pathway were genotyped in an 8-week clinical trial of 470 adults with moderate to severe asthma. We then validated our findings in a second population of individuals with childhood asthma in a 4-year clinical trial of inhaled corticosteroids and a third population of adults with asthma. One gene, corticotrophin-releasing hormone receptor 1 (CRHR1, NM_004382), demonstrated multiple single nucleotide polymorphism associations within each of the three populations. The approach of a test and multiple replication populations is a valuable strategy in asthma pharmacogenetics, which can insure valid association findings.

full text

Saturday, October 22, 2005

Exercise Induced Asthma

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Exercise Induced Asthma


By Paddy Moogan

How can exercise induce asthma?

At the same time as healthy exercise can be handled by patients, exercise can often be the cause of an asthma attack.

Symptoms of exercise induced asthma…

Wheezing, coughing and a tightening of the chest are all symptoms of exercise induced asthma. These symptoms will usually be felt after beginning the exercise and will gradually worsen even after exercise stops.

Why does exercise induce asthma?

Even after years of research, the reasons for exercise induced asthma are unclear. However in theory asthma sufferers will breathe faster which does not allow for the nose and airways to add moisture to the air, therefore the air being taken in is dry and cold. This intake of cold, dry air is thought to trigger asthma symptoms.

How do Doctors diagnose exercise induced asthma?

Doctors will often refer to a patient’s medical history and perhaps perform peak flow tests in order to determine if a case of exercise induced asthma exists. However in some cases it may be difficult for the Doctor to make a full diagnosis without further tests at a specialised unit.

How to manage your exercise induced asthma…

• Long distance or cross country running can be triggers for asthma attacks due to the intake of cold air without any breaks.
• On the other hand sports such as football, basketball or tennis are less likely to induce an attack if short breaks are taken.
• An excellent sport for asthma sufferers to take part in is swimming, I can speak from experience on this matter. The theory behind this is that warm humid air in the swimming pool is less likely to trigger asthma symptoms. It must be noted however that heavily chlorinated pools can have the opposite effect, as can swimming in cold water.
• Another good exercise for people with breathing problems is yoga, the muscles are relaxed and can help by practising breathing exercises.

Remember – asthma should not stop you from enjoying sports… Personally I have suffered with asthma since I was very young, however I have always taken part in sports and although I still have breathing problems from time to time, I can control them by remembering a few things…

• Take the correct medication
• Consult your Doctor regularly and ask for advice
• Start the sports slowly and pace yourself to see how much you can do comfortably.

Keep your asthma controlled during exercise by following a few steps…

• Taking regular exercise and taking part in sports can have a positive effect on your breathing problems and reduce exercise induced asthma in the long term.
• Warm up and warm down.
• Try to avoid cold air, this can induce breathing problems. If you take part in sports in cold weather it is a good idea to cover your nose and mouth with a scarf.

Keeping your child’s asthma under control at school…

Unless your child suffers from very severe asthma, they should be able to take part in PE and extra curricular sports at school. However remember to inform their teachers of their asthma and keep spare medication at the school in case your child’s runs out or loses it. Teachers can also encourage the child to warm up and warm down whilst making sure the child doesn’t over exert themselves.

Taking part in competitive sports…

The usual inhaler medications are not banned in competitive sports, however you should register the fact that you have asthma and are taking medication to control it. You should make sure that your friends who you play the sport with are aware of your asthma in case of emergencies.

Taking part in adventure sports…

It is recommended that you consult your Doctor before taking part in adventure sports, if you are cleared to take part then make sure that you inform your instructor of your breathing problems. Also ensure that you keep your medication close to hand. If you need insurance for taking part in adventure sports then you should declare that you have asthma before taking out the policy.

Can I take part in scuba-diving?

Recently the medical profession has recognised that people with controlled symptoms of asthma can take part in scuba-diving. But the pressures involved in scuba-diving such as the exposure to cold air and the possibility of stress and emotion, can induce breathing problems.

If you are planning to take part in scuba-diving whilst on holiday abroad, it is worth checking what the guidelines are on scuba-diving for the country you are travelling to. Some countries do not allow asthma sufferers to take part in scuba-diving.

There are several recommendations made by the British Sub-Aqua Club, for those with mild controlled asthma…

• You have not needed to use your inhaler or shown symptoms of asthma within the last 48 hours.
• You do not have asthma that is triggered by cold, exercise stress or emotion.

Can I take part in mountaineering?

Mountaineering shouldn’t be a problem as long as you are physically fit and your asthma is controlled. You should also make sure you plan well for your trip and take more than enough medication.

If your asthma is triggered by air pollution, then the mountain environment is ideal for you. Dust mites are unable to live at the low temperatures of the mountains and therefore the air is cleaner.

However there are several asthma triggers that exist in the mountains such as the cold, dry air and exercise.

The British Mountaineering Council provides good medical advice on high altitude mountaineering.

Can I take part in skiing?

Skiing shares many of the same principles as mentioned above in mountaineering, for example people with well controlled asthma should be able to enjoy skiing without any problems. However as usual if you are concerned it is best to seek medical advice prior to engaging in this activity.

You should seek advice particularly if you are planning to take part in cross country skiing which can be a stronger trigger than downhill skiing.

What about parachute jumping?

As a general rule you can parachute or skydive if…

• Exercise does not trigger your asthma
• You can completely control your asthma
• Cold air does not trigger your asthma


As always you should consult your Doctor before taking part in this type of activity. You can also find more information from the British Parachute Association.

By Patrick Moogan

Founder of http://www.AsthmaOnline.co.uk. Patrick has suffered with asthma since he was a small child and knows how it feels to have an asthma attack. He writes articles in the best way he knows how, from personal experience.

Article Source: http://EzineArticles.com/













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Saturday, October 15, 2005

Asthma Treatment and Medication

Asthma Treatment and Medication
By Daniel Lanicek

Asthma is a chronic lung disease that effects over 30 million Americans alone and researchers estimate that 10 – 15% of the world population suffers from asthma. People with asthma have extra sensitive or hyper-responsive airways. The airways become irritated and narrow and constrict during an asthma attack, causing increased resistance to airflow, and obstructing the flow of the air to and from the lungs.

Most often asthma must be treated with prescription medicine. There are two main types of medicines for the treatment of asthma. Quick relief medicines, also called relievers, give rapid, short-term relief and are taken when asthma symptoms worsen potentially leading to an asthma attacks. The effects of these medicines are felt within minutes. Long-term control medicines, also called preventers, are taken every day, usually over long periods of time, to control chronic symptoms and to prevent asthma attacks. The full effects of these medicines are felt after taking them for a few weeks. People with persistent asthma need long-term control medicines.

Some asthma drugs treat asthma by resembling two of our hormones. These two hormones are adrenaline (epinephrine in the USA) and hydrocortisone (a steroid).

Adrenaline (epinephrine) is pumped into our bloodstream when we have a sudden fright or emergency. It is the quick-acting hormone from the middle of the adrenal glands near our kidneys. It makes your pulse race, your heart thump, and readies your body for emergency action. In asthma, the medicines which resemble adrenaline quickly relieve asthma for a short time.

Hydrocortisone comes from the outer part of our adrenal glands, called the 'cortex'. It is also partly an “emergency hormone” but it works much more slowly, for much longer, and in a completely different way to adrenaline. Medicines which resemble hydrocortisone slowly allow the lining of air tubes in an asthma sufferer to become normal. As a result, your asthma becomes less severe and you are less likely to get asthma attacks. So these steroid medicines are called preventers. There are other asthma 'preventers', but the steroids are the most powerful.

Quick relief medicines are used only when needed. A type of quick relief medicine is a short-acting inhaled bronchodilator. Bronchodilators work by relaxing the muscles that have tightened around the airways. They help open up airways quickly and ease breathing. They are sometimes called "rescue" or "relief" medicines because they can stop an asthma attack very quickly. These medicines act quickly but their effects only last for a short period of time. People with asthma should take quick relief medicines when they first begin to feel asthma symptoms like coughing, wheezing, chest tightness, or shortness of breath. Anyone who has asthma should always have one of these inhalers nearby in case of an attack. For severe attacks, your doctor may use steroids to treat the inflammation.

The most effective, long-term control medication for asthma is an inhaled corticosteroid. This medicine reduces the swelling of airways that makes asthma attacks more likely. Inhaled corticosteroids are the preferred treatment for controlling mild, moderate, and severe persistent asthma. They are safe when taken as directed by your doctor. Inhaled medicines go directly into your lungs where they are needed. There are many kinds of inhalers that require different techniques, and it is important to know how to use your inhaler correctly. In some cases, steroid tablets or liquid are used for short times to bring asthma under control. The tablet or liquid form may also be used to control severe asthma.

Many people with asthma need both a short-acting bronchodilator to use when asthma symptoms worsen rapidly and long-term daily asthma control medication to treat the ongoing inflammation. Over time, your doctor may need to make changes in your asthma medication. You may need to increase your dose, lower your dose, or try a combination of medications. Be sure to work with your doctor to find the best treatment for your asthma. The goal is to use the least amount of medicine necessary to control your asthma and to find the right medicine for you.

Daniel Lanicek is the creator of asthmaexplained.com. Learn more about asthma at http://www.asthmaexplained.com

Sunday, October 02, 2005

What Is Asthma?

What Is Asthma?

Provided by ehealthMD.com

Asthma is a condition that affects the air passages of the lungs. It is a two-step problem:

When a person has asthma, the air passages are inflamed, which means that the airways are red and swollen.
Inflammation of the air passages makes them over extra-sensitive to a number of different things that can "trigger," or bring on, asthma symptoms.

During breathing, air is normally brought in through the nose. After being warmed, filtered, and humidified as it passes through the throat and into the windpipe, called the trachea (TRAY-kee-a). The trachea divides into two large tubes called the right bronchus (BRONG-kus) and left bronchus. These then split up into much smaller tubes, which in turn branch into thousands of very small airways called bronchioles (BRONG-kee-olz). It is the large and small bronchi that are generally affected in asthma.




When a person is exposed to one of these irritants, or triggers, the oversensitive air passages react by becoming narrower, swollen, and even more inflamed. This obstructs airflow to and from the lungs and makes it very difficult for the person to breathe.

Nice To Know

Is All Asthma The Same?

Asthma is a chronic condition. This means that while it often looks like it goes away for awhile, the inflammation of the air passages remains present all the time. However, in some instances, this inflammation may go unnoticed for long periods of time. As long as the air passages are inflamed, asthma can flare up at any time. This is one of the reasons that an awareness of the triggers that cause the flare-ups is so important in preventing asthma episodes.

Allergic asthma - Allergic asthma is most common in children and adolescents. Usually, but not always, the allergies that cause the asthma appear before the age of 35. An asthma attack or episode occurs when a person comes into contact with something to which he or she has developed an allergy.
Nonallergic asthma - This type of asthma is most common in middle-aged adults. Asthma attacks may occur in response to triggers such as exercise, cold air, or respiratory infections. The allergic mechanism is not responsible for the asthmatic reaction.


What Is An Asthma Episode (Asthma Attack)?

Asthma symptoms can vary from very mild to very severe. Some adults with asthma have only seasonal bouts of symptoms. Some have symptoms only after exercise or after exposure to something to which they are allergic, such as a dog or cat. Others have a chronic form of the disease and experience asthma symptoms almost daily.

In an "asthma episode," also known as an "asthma attack," the symptoms develop because the oversensitive airways of the lung react by becoming more inflamed and narrows, thus obstructing the normal flow of air through the air passages. The reduced size of the air passages occurs because:

The muscles around the airways tighten
The linings of the airways become swollen
The normal secretion of the airways (called mucus) becomes "trapped," thus clogging the airways

As the airways become narrower and more obstructed, it takes extra effort to breathe and force air through them. The air may make a whistling or wheezing sound as it goes past the narrowed parts of the air passages. A person having an asthma attack may also cough a lot and spit up a lot of very sticky mucus.

So one or more of the following symptoms may occur once the airways have narrowed in response to a trigger:

Coughing. Coughing is often a sign of asthma, but is easily overlooked. As a general rule, healthy people don't cough unless they have something in their throats or have a cold.
Wheezing. Wheezing is a whistling noise heard during breathing, as if something is "caught" in one of the breathing passages.
Tightness of the chest. Many adults with asthma describe a tightness of the chest, an uncomfortable feeling caused by over-inflation of the lungs due to difficulty in pushing air out through the narrowed airways.
Shortness of breath. Shortness of breath is the feeling that a breath is barely finished before another is needed. It has been described as "air hunger" by some people.
Mucus production. Many people with asthma produce excessive, thick mucus that obstructs the airways, which can lead to coughing.

For many people, asthma symptoms are worse at night and in the early morning or after exercise. Furthermore, an asthma episode often gives early warning signs, thus giving the person time to act.

Nice To Know

Q. What makes my breathing passages so sensitive to triggers?

A. The underlying cause of the sensitivity in the airways is inflammation. Inflamed airways are highly reactive to triggers. In other words, they are easily irritated and respond by contracting, swelling, and filling with thick mucus. Some of the breathing passages don't have much supporting cartilage in their walls the way the windpipe does. As a result, they are not very "stiff" and are easily squeezed closed. Think of them as tiny tubes with thin muscle fibers wrapped around them like "rubber bands." If the "rubber bands" (airway muscle) tighten, the thin-walled passages are more easily choked off, making you short of breath.


Are Asthma Episodes Dangerous?

Most of the time asthma episodes are mild, and the airways will open up in a few minutes to a few hours in response to medication. But some attacks can be severe, lasting for a long time and not responding to the regular medication. And they can be very dangerous. A very severe, prolonged attack can threaten a person's life. Such an episode requires immediate emergency attention in a hospital.

Learning to recognize signals and take action to prevent asthma symptoms from becoming worse is an important step in the long-term control of asthma. So is managing an episode if it does occur.

Learning all about asthma will ultimately help a person have fewer and milder episodes and reduce the risk of a more serious attack. This includes understanding about:

The way your lungs work
The things that cause asthma episodes
The ways you can avoid those things
The medicines that help prevent and control symptoms
What Does "Good Asthma Control" Mean?

The long-term goal in asthma management is "good asthma control." In fact, because of a better understanding of the disease and the development of newer drugs, drug treatments are so effective that many adults with asthma can go for long periods of time without symptoms.

Good asthma control includes the following goals:

There is no wheezing, coughing, or shortness of breath.
Nighttime sleep is not interrupted by asthma symptoms.
Exercise and daily activities can be carried out normally.
Reliever medication is used less than three times per week.

For asthma treatment to be successful you need to learn all you can about asthma and its treatment, work closely with your doctor, and cooperate fully with other members of your health care team.

Facts About Asthma

The process of moving air into and out of the lungs is something most people take for granted. But for as many as 15 million Americans living with asthma, this simple activity requires significant effort.

Asthma cannot be cured, but with proper treatment it can be effectively controlled. Good asthma control allows most adults to live full, active, trouble-free lives.

Without satisfactory control of asthma, long-term damage can occur in the respiratory system. Poorly controlled asthma can lead to reduced physical activities, missed work, and extra visits to the emergency department.

For most adults with asthma, a reduced quality of life doesn't have to happen. Arming yourself with information is an important step in maintaining a healthy life.

Asthma

Asthma
From Wikipedia, the free encyclopedia.

Young asthmatic girl using an inhaler attached to a spacer.Asthma is a disease of the respiratory system in which the airways unexpectedly and suddenly narrow, often in response to a "trigger" such as exposure to an allergen, cold air, exercise, or emotional stress. This narrowing causes symptoms such as wheezing, shortness of breath, chest tightness, and coughing, which are the hallmarks of asthma. Between episodes, patients normally feel fine.

The disorder is a chronic inflammatory condition in which the airways develop increased responsiveness to various stimuli, characterized by bronchial hyperresponsiveness, inflammation, increased mucus production and intermittent airway obstruction. The symptoms of asthma, which can range from mild to life threatening, can usually be controlled with a combination of drugs and lifestyle changes.

Public attention in the developed world has recently focused on asthma because of its rapidly increasing prevalence, affecting up to one in four urban children.[1] Susceptibility to asthma can be explained in part by genetic factors, but no clear pattern of inheritance has been found. Asthma is a complex disease that is influenced by multiple genetic, developmental, and environmental factors, which interact to produce the overall condition.

Contents [hide]
1 History
2 Signs and symptoms
3 Diagnosis
3.1 Diagnosing asthma
3.2 Differential diagnosis
4 Pathophysiology
4.1 Bronchoconstriction
4.2 Bronchial inflammation
4.3 The immune response
4.4 Pathogenesis
5 Treatment
5.1 Relief medication
5.2 Prevention medication
5.3 Long-acting β2-agonists
5.4 Emergency treatment
5.5 Alternative medicine
6 Prognosis
7 Epidemiology
7.1 Asthma and athletics
8 References
9 External links



[edit]
History
The word asthma is derived from the Greek aazein ("sharp breath"), which first appears in the Iliad (although it is used here in its literal Greek sense, not in reference to the disease).[2] Hippocrates was the first to use it to refer to a medical condition. He noticed that its associated "spasms" were more likely to occur in tailors, fisherman, and metal workers. Six centuries later, Galen wrote much about asthma and found that it was caused by bronchial obstruction. Moses Maimonides, an influential medieval rabbi, philosopher, and physician, wrote a treatise on asthma, describing its prevention, diagnosis, and treatment.[3] In the 17th century, Bernardino Ramazzini noted a connection between asthma and organic dust. The use of bronchodilators started in 1901, but it was not until the 1960s that the inflammatory component of asthma was recognized, and anti-inflammatory medications were added to the regimen.

[edit]
Signs and symptoms
An acute exacerbation of asthma is referred to colloquially as an asthma attack. The clinical hallmarks of an attack are shortness of breath (dyspnea) and wheezing, the latter "often being regarded as the sine qua non".[4] A cough—sometimes producing clear sputum—may also be present. The onset is often sudden; there is a "sense of constriction" in the chest, breathing becomes difficult, and wheezing occurs (typically in both respiratory phases).

Signs of an asthmatic episode are wheezing, rapid breathing (tachypnea), prolonged expiration, a rapid heart rate (tachycardia), rhonchous lung sounds (audible through a stethoscope), and overinflation of the chest. During a serious asthma attack, the accessory muscles of respiration may be used, shown as in-drawing of tissues between the ribs and above the sternum and clavicles, and the presence of a paradoxical pulse (a pulse that is weaker during inhalation and stronger during exhalation).[4] During very severe attacks, an asthma sufferer can turn blue from lack of oxygen and can experience chest pain or even loss of consciousness. Severe asthma attacks may lead to respiratory arrest and even to death. Despite the severity of symptoms during an asthmatic episode, between attacks an asthmatic may show few signs of the disease.

[edit]
Diagnosis
[edit]
Diagnosing asthma
In most cases, a physician can diagnose asthma on the basis of typical findings in a patient's clinical history and examination. Asthma is strongly suspected if a patient suffers from eczema or other allergic conditions—suggesting a general atopic constitution—or has a family history of asthma. While measurement of airway function is possible for adults, most new cases are diagnosed in children who are unable to perform such tests. Diagnosis in children is based on a careful compilation and analysis of the patient's medical history and subsequent improvement with an inhaled bronchodilator medication. In adults, diagnosis can be made with a peak flow meter (which tests airway restriction), looking at both the diurnal variation and any reversibility following inhaled bronchodilator medication.

Testing peak flow at rest (or baseline) and after exercise can be helpful, especially in young asthmatics who may experience only exercise-induced asthma. If the diagnosis is in doubt, or if chronic obstructive pulmonary disease is suspected, a more formal lung function testing may be conducted. Once a diagnosis of asthma is made, a patient can use peak flow meter testing to monitor the severity of the disease.

[edit]
Differential diagnosis
Before diagnosing someone as asthmatic, alternative possibilities should be considered. A physician taking a history should check whether the patient is using any known bronchoconstrictors (substances that cause narrowing of the airways, e.g., certain anti-inflammatory agents or beta-blockers).

Only a minority of asthma sufferers have any identifiable allergy trigger. The majority of these triggers can often be identified from the history; for instance, asthmatics with hay fever or pollen allergy will have seasonal symptoms, those with allergies to pets may experience an abatement of symptoms when away from home, and those with occupational asthma may improve during leave from work. Occasionally, allergy tests are warranted and, if positive, may help in identifying avoidable symptom triggers.

After pulmonary function has been measured, radiological tests, such as a chest X-ray or CT scan, may be required to exclude the possibility of other lung diseases. In some people, asthma may by triggered by gastroesophageal reflux disease, which can be treated with suitable antacids. Very occasionally, specialized tests after inhalation of methacholine—or even less commonly histamine—may be performed.

[edit]
Pathophysiology
[edit]
Bronchoconstriction

During an asthma episode, inflamed airways react to environmental triggers such as smoke, dust, or pollen. The airways narrow and produce excess mucus, making it difficult to breathe.In essence, asthma is the result of an abnormal immune response in the bronchial airways.[5] The airways of asthmatics are "hypersensitive" to certain triggers, also known as stimuli (see below). In response to exposure to these triggers, the bronchi (large airways) contract into spasm (an "asthma attack"). Inflammation soon follows, leading to a further narrowing of the airways and excessive mucus production, which leads to a coughing and other breathing difficulties.

There are seven categories of stimuli:

allergens, typically inhaled, which include waste from common household insects, such as the house dust mite and cockroach, grass pollen, mould spores and pet epithelial cells;
medications, including aspirin[6] and the common β-adrenergic antagonist (beta blockers);
air pollution, such as ozone, nitrogen dioxide, and sulfur dioxide, which is thought to be one of the major reasons for the high prevalence of asthma in urban areas;
various industrial compounds and other chemicals, notably sulfites;
early childhood infections, especially viral respiratory infections;
exercise, of which the effects differ somewhat from those of the other triggers; and
emotional stress, which is poorly understood as a trigger.
[edit]
Bronchial inflammation
The mechanisms behind allergic asthma—i.e., asthma resulting from an immune response to inhaled allergens—are the best understood of the causal factors. When allergens are inhaled by any person (asthmatic or not), they travel to the inner airways, where they are ingested by certain cells there. These cells digest the allergen and present pieces of the allergen to other cells of the immune system. In most people, those other immune cells (TH0 cells) will check and ignore the allergen molecules. However, in people who will develop asthma, those immune cells will transform into a different type of cell (TH2) instead of passing by the pieces of allergen, for complex reasons that are not well understood. These TH2 cells activate mainly the antibody-related part of the immune system, thus producing antibodies against the original allergen. Later, when an asthmatic inhales the same allergen, those antibodies recognize the allergen and the immune system is activated. Inflammation results, producing chemicals that cause the airways to constrict and produce more mucus. In addition, other immune cells are summoned, which are responsible for the subsequent effects of the asthma attack.

[edit]
The immune response
More technically, primary exposure to a foreign antigen—such as pollen or cigarette smoke—can trigger the development of asthmatic symptoms. Once an inhaled antigen becomes trapped in the airways, it is enzymatically degraded into shorter peptides by antigen presenting cells (APCs) such as dendritic cells. APCs take the peptides derived from the antigen and express them on the cell surface in the binding groove of the class II major histocompatiblity complex (MHC) molecule. Now located on the cell surface, the antigen-MHC complex is presented to T cells, which express a receptor that is specific to the MHC II peptide.[5]

Presented with the antigen-MHC II complex, T helper 0 (TH0) cells become activated and start to differentiate into either T helper type 1 (TH1) or type 2 (TH2) cells. The selective differentiation of TH0 cells has profound consequences for the immune system: TH1 cell production leads to cell-mediated immunity, while the production of predominantly TH2 cells provides humoral immunity. The resulting balance of TH1 or TH2 cells is a crucial variable in the development of asthma. The dominance of the TH2 cell type appears to be necessary for the development of asthma. In one study, mice that lack the ability to create TH1 cells displayed an asthma-like phenotype.[7] The variables that decide the fate of TH1 vs. TH2 cells are not well understood, but depend on many factors, including childhood exposure to infectious agents and the cytokines elicited by those agents.

One cytokine secreted by TH2 cells—IL-4—combined with the action of other cytokines induces synthesis by antigen-stimulated B cells of IgE, an allergen-specific antibody. IgE binds allergens and then receptors on mast cells, basophils, and eosinophils in the airway epithelium. Subsequent exposure of the same antigen to these cells in the airway epithelium initiates the acute-phase reaction of asthma. Stimulated mast cells in the airway release preformed granules of mediators such as histamine, eicosanoids, and cytokines. These molecules are responsible for the symptoms of asthma. They affect the mucosa of the airways, increasing mucosal edema, and mucus production, smooth muscle constriction, and recruit other immune cells, thereby exacerbating the reaction.

The late phase of an asthmatic reaction is characterized by an influx of inflammatory and immune cells during the first several hours after antigen exposure. These cells—particularly eosinophils—secrete a series of cytokines, leukotrienes, and polypeptides, which contribute to hyperresponsiveness, mucus secretion, bronchoconstriction, and sustained inflammation.

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Pathogenesis
The fundamental problem in asthma appears to be immunological: young children in the early stages of asthma show signs of excessive inflammation in their airways. Epidemiological findings give clues as to the pathogenesis: the incidence of asthma seems to be increasing worldwide; asthma is more common in more affluent countries, and more common in wealthier socioeconomic groups.

One theory of pathogenesis is that asthma is a disease of hygiene. In nature, babies are exposed to bacteria and other antigens soon after birth, "switching on" the TH1 lymphocyte cells of the immune system that deal with bacterial infection. If this stimulus is insufficient—as it may be in modern, clean environments—then TH2 cells predominate, and asthma and other allergic diseases may develop. This "hygiene hypothesis" may explain the increase in asthma in affluent populations. The TH2 lymphocytes and eosinophil cells that protect us against parasites and other infectious agents are the same cells responsible for the allergic reaction. In the developed world, these parasites are now rarely encountered, but the immune response remains and is wrongly triggered in some individuals by certain allergens.

Another theory is based on the correlation of air pollution and the incidence of asthma. Although it is well known that substantial exposures to certain industrial chemicals can cause acute asthmatic episodes, it has not been proved that air pollution is responsible for the development of asthma. In Western Europe, most atmospheric pollutants have fallen significantly over the last 40 years, while the prevalence of asthma has risen.

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Treatment
The most effective treatment for asthma is identifying triggers, such as pets or aspirin, and limiting or eliminating exposure to them. Desensitization is commonly attempted, but has not been shown to be effective. As is common with respiratory disease, smoking adversely affects asthmatics in several ways, including an increased severity of symptoms, a more rapid decline of lung function, and decreased response to preventive medications.[8] Asthmatics who smoke typically require additional medications to help control their disease. Furthermore, exposure by both nonsmokers and smokers to secondhand smoke is detrimental, resulting in more severe asthma, more emergency room visits, and more asthma-related hospital admissions.[9] Smoking cessation and avoidance of those who smoke is strongly encouraged in asthmatics.[10]

The specific medical treatment recommended to patients with asthma depends on the severity of their illness and the frequency of their symptoms. The Expert panel report 2: Guidelines for the diagnosis and management of asthma (EPR-2)[10] of the US National Asthma Education and Prevention Program, and the British guideline on the management of asthma [11] are broadly used and supported by many doctors. Bronchodilators are recommended for short-term relief in all patients. For those who experience occasional attacks, no other medication is needed. For those with mild persistent disease (more than two attacks a week), low-dose inhaled glucocorticoids—or alternatively, a oral leukotriene modifier, a mast-cell stabilizer, or theophylline—may be administered. For those who suffer daily attacks, a higher dose of glucocorticoid in conjunction with a long-acting inhaled β-2 agonist may be prescribed; alternatively, a leukotriene modifier or theophylline may substitute for the β-2 agonist. In severe asthmatics, oral glucocorticoids may be added to these treatments during severe attacks.

For those in whom exercise can trigger an asthma attack (exercise-induced asthma), higher levels of ventilation and cold, dry air tend to exacerbate attacks. For this reason, activities in which a patient breathes large amounts of cold air, such as cross-country skiing, tend to be worse for asthmatics, whereas swimming in an indoor, heated pool, with warm, humid air, is less likely to provoke a response.[4]

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Relief medication

A typical inhaler.Symptomatic control of episodes of wheezing and shortness of breath is generally achieved with fast-acting bronchodilators. These are typically provided in pocket-sized, metered-dose inhalers (MDIs—see the image to the right). In young sufferers, who may have difficulty with the coordination necessary to use inhalers, or those with a poor ability to hold their breath for 10 seconds after inhaler use (generally the elderly), a device called an asthma spacer is used. An asthma spacer is an enclosed plastic cylinder that mixes the medication with air in a simple tube, making it easier for patients to receive a full dose of the drug (see top image). For a minority of patients with severe asthma, a nebulizer—which provides a larger, continuous dose—is sometimes required.

Relievers include:

Short-acting, selective beta2-adrenoceptor agonists (salbutamol [albuterol], levalbuterol, terbutaline, bitolterol, pirbuterol, procaterol, fenoterol, bitolterol, reproterol). The major side effect is tremors; however, this has been greatly reduced by the use of inhaled drugs, which are capable of targeting the lungs, rather than oral medications, which tend to be distributed throughout the body. There may also be cardiac side effects at higher doses; these have become rare with the advent of selective agents.
Older, less selective adrenergic agonists, such as inhaled epinephrine and ephedrine tablets—both of which, unlike other medications, are available over the counter in the US under the Primatene brand. Cardiac side effects, although uncommon, occurred more often with the less selective drugs. Nowadays, they are usually avoided in patients with heart disease.
Anticholinergic medications, such as ipratropium bromide may be used instead. They have no cardiac side effects and thus can be used in patients with heart disease; however, they take up to an hour to achieve their full effect and are not as powerful as the β2-adrenoreceptor agonists.
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Prevention medication
Current treatment protocols recommend an inhaled corticosteroid, which helps to suppress inflammation and reduces the swelling of the lining of the airways in anyone who has frequent (greater than twice a week) need of relievers or who has severe symptoms. If symptoms persist, additional preventive drugs are added until the asthma is controlled.

Preventive agents include the following.

Inhaled glucocorticoids (fluticasone, budesonide, beclomethasone, mometasone, flunisolide, and triamcinolone).
Antimuscarinics/anticholinergics (ipratropium, oxitropium), which have a mixed reliever and preventer effect.
Leukotriene modifiers (montelukast, zafirlukast, pranlukast, and zileuton).
Mast cell stabilizers (cromoglicate (cromolyn), and nedocromil).
Methylxanthines (theophylline and aminophylline), which are sometimes considered if sufficient control cannot be achieved with inhaled glucocorticoids and long-acting β-agonists alone.
Antihistamines, often used to treat allergic symptoms that may underlie the chronic inflammation. In more severe cases, hyposensitization ("allergy shots") may be recommended.
Omalizumab, an IgE blocker; this can help patients with severe allergic asthma that does not respond to other drugs. However, it is expensive and must be injected.
If chronic acid indigestion (GERD) contributes to a patient's asthma, it should also be treated, because it may prolong the respiratory problem.
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Long-acting β2-agonists
Long-acting bronchodilators (LABD) give a 12-hour effect and are used to give a smoothed symptomatic effect (used morning and night). While patients report improved symptom control, these drugs do not replace the need for routine preventers, and their slow onset means the short-acting dilators may still be required.

Currently available long-acting beta2-adrenoceptor agonists include salmeterol, formoterol, bambuterol, and sustained-release oral albuterol. Combinations of inhaled steroids and long-acting bronchodilators are becoming more widespread; the most common combination currently in use is fluticasone/salmeterol (Advair in the United States, and Seretide in the UK).

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Emergency treatment
When an asthma attack is unresponsive to a patient's usual medication, other treatments are available to the physician or hospital:[12]

oxygen to alleviate the hypoxia (but not the asthma per se) that results from extreme asthma attacks;
nebulized salbutamol (2.5–5 mg), usually three in rapid succession ("back-to-back");
systemic steroids, oral or intravenous (prednisone, prednisolone, methylprednisolone, dexamethasone, or hydrocortisone)
other bronchodilators that are occasionally effective when the usual drugs fail:
nonspecific beta-agonists, injected or inhaled (epinephrine, isoetharine, isoproterenol, metaproterenol);
anticholinergics, IV or nebulized, with systemic effects (glycopyrrolate, atropine);
methylxanthines (theophylline, aminophylline);
inhalation anesthetics that have a bronchodilatory effect (isoflurane, halothane, enflurane);
the dissociative anesthetic ketamine, often used in endotracheal tube induction
magnesium sulfate, intravenous; and
intubation and mechanical ventilation, for patients in or approaching respiratory arrest.
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Alternative medicine
Many asthmatics, like those who suffer from other chronic disorders, use alternative treatments; surveys show that roughly 50% of asthma patients use some form of unconventional therapy.[13] [14] There are little data to support the effectiveness of most of these therapies. A Cochrane systematic review of acupuncture for asthma found that there was no evidence of efficacy.[15] A similar review of air ionizers found no evidence that they improve asthma symptoms or benefit lung function; this applied equally to positive and negative ion generators.[16] A study of "manual therapies" for asthma, including osteopathic, chiropractic, physiotherapeutic and respiratory therapeutic maneuvers, found no evidence to support their use in treating asthma;[17] these maneuvers include various osteopathic and chiropractic techniques to "increase movement in the rib cage and the spine to try and improve the working of the lungs and circulation"; chest tapping, shaking, vibration, and the use of "postures to help shift and cough up phlegm". On the other hand, one meta-analysis found that homeopathy has a potentially mild benefit in reducing symptom intensity;[18] however, the number of patients involved in the analysis was small, and subsequent studies have not supported this finding.[19] Several small trials have suggested some benefit from various yoga practices, ranging from integrated yoga programs[20]—"yogasanas, Pranayama, meditation, and kriyas"—to sahaja yoga[21], a form of meditation. A randomized, controlled trial of just 39 patients suggested that the Buteyko breathing technique may moderately reduce the need for beta-agonists among asthmatics, but found no objective improvement in lung function.[22] See also complementary and alternative medicine.

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Prognosis
The prognosis for asthmatics is good, especially for children with mild disease. For asthmatics diagnosed during childhood, 54% will no longer carry the diagnosis after a decade. The extent of permanent lung damage in asthmatics is unclear. Airway remodelling is observed, but it is unknown whether these represent harmful or beneficial changes.[5] Although there are mixed reports, most studies show that early treatment with glucocorticoids prevents or ameliorates decline in lung function as measured by several parameters.[23] However, there does not appear to be any progression from mild to moderate or moderate to severe asthma, regardless of treatment. For those who continue to suffer from mild symptoms, corticosteroids can help most to live their lives with few disabilities. The mortality rate for asthma is low, with around 6000 deaths per year in a population of some 10 million patients in the United States.[4]

Many asthma deaths are preventable, so aggresively identifying patients who are not well controlled is imperative. The 1998, pharmaceutical company sponsored, Asthma in America telephone study showed that asthmatics, like others with chronic diseases, become used to the presence of symptoms, under-assess the severity of their own illness and are less likely to seek medical attention, or do it late. Of those asthmatics who fit the description of Moderate or Severe Persistent Asthma, about 66% and 33% respectively considered their asthma "Well Controlled" or "Completely Controlled".

[edit]
Epidemiology

The prevalence of childhood asthma has increased since 1980, especially in younger children.Asthma is usually diagnosed in childhood. The risk factors for asthma include:

a personal or family history of asthma or atopy;
triggers (see Pathophysiology above);
premature birth or low birth weight;
viral respiratory infection in early childhood;
maternal smoking;
being male, for asthma in prepubertal children; and
being female, for persistence of asthma into adulthood.
There is a reduced occurrence of asthma in people who were breast-fed as babies. Current research suggests that the prevalence of childhood asthma has been increasing. According to the Centers for Disease Control and Prevention's National Health Interview Surveys, some 9% of US children below 18 years of age had asthma in 2001, compared with just 3.6% in 1980 (see figure). The World Health Organization (WHO) reports[24] that some 8% of the Swiss population suffers from asthma today, compared with just 2% some 25–30 years ago. Although asthma is more common in affluent countries, and more common in higher socioeconomic groups within countries, it is by no means a problem restricted to the affluent; the WHO estimate that there are between 15 and 20 million asthmatics in India. In the US, urban residents and Hispanics and African Americans are affected more than the population as a whole. Globally, asthma is responsible for around 180,000 deaths annually.[24]

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Asthma and athletics
Asthma appears to be more prevalent in athletes than in the general population. One survey of participants in the 1996 Summer Olympic Games showed that 15% had been diagnosed with asthma, and that 10% were on asthma medication.[25] There appears to be a relatively high incidence of asthma in sports such as cycling, mountain biking, and long-distance running, and a relatively low incidence in weight lifting and divers. It is unclear how much of these disparities are because of the effects of training in the sport, and self-selection of sports that may appear to minimize the triggering of asthma.[25] [26]




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References
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↨ Marketos SG, Ballas CN. Bronchial asthma in the medical literature of Greek antiquity. J Asthma. 1982;19(4):263-9. PMID 6757243
↨ Rosen F. Moses Maimonides' treatise on asthma. Thorax. 1981;36:245-251. PMID 7025335
↨ McFadden ER, Jr. Asthma. In Kasper DL, Fauci AS, Longo DL, et al (eds.). Harrison's Principles of Internal Medicine (16th Edition), pp. 1508-1516. New York: McGraw-Hill;2004.
↨ Maddox L, Schwartz DA. The Pathophysiology of Asthma. Annu. Rev. Med. 2002, 53:477-98. PMID 11818486
↨ Jenkins C, Costello J, Hodge L. Systematic review of prevalence of aspirin induced asthma and its implications for clinical practice. BMJ 2004;328:434. PMID 14976098
↨ Finotto S, Glimcher L. T cell directives for transcriptional regulation in asthma. Springer Semin. Immunopathology 2004;25(3-4):281-94. PMID 15007632
↨ Thomson NC, Spears M. The influence of smoking on the treatment response in patients with asthma. Curr Opin Allergy Clin Immunol. 2005;5(1):57-63. PMID 15643345
↨ Eisner MD, Yelin EH, Katz PP, et al. Exposure to indoor combustion and adult asthma outcomes: environmental tobacco smoke, gas stoves, and woodsmoke. Thorax. 2002;57(11):973-8. PMID 12403881
↨ National Asthma Education and Prevention Program. Expert Panel Report: Guidelines for the Diagnosis and Management of Asthma. National Institutes of Health pub no 97-4051. Bethesda, MD, 1997. (PDF)
↨ British Thoracic Society & Scottish Intercollegiate Guidelines Network (SIGN). British Guideline on the Management of Asthma. Guideline No. 63. Edinburgh:SIGN; 2004. (HTML, Full PDF, Summary PDF)
↨ Rodrigo GJ, Rodrigo C, Hall JB. Acute asthma in adults: a review. Chest. 2004;125(3):1081-102. PMID 15006973
↨ Blanc PD, Trupin L, Earnest G, et al. Alternative therapies among adults with a reported diagnosis of asthma or rhinosinusitis: data from a population-based survey. Chest. 2001;120(5):1461-7. PMID 11713120
↨ Shenfield G, Lim E, Allen H. Survey of the use of complementary medicines and therapies in children with asthma. J Paediatr Child Health. 2002;38(3):252-7. PMID 12047692
↨ McCarney RW, Brinkhaus B, Lasserson TJ, et al. Acupuncture for chronic asthma. Cochrane Database Syst Rev. 2004;(1):CD000008. PMID 14973944
↨ Blackhall K, Appleton S, Cates CJ. Ionisers for chronic asthma. Cochrane Database Syst Rev. 2003;(3):CD002986 PMID 12917939
↨ Hondras MA, Linde K, Jones AP. Manual therapy for asthma. Cochrane Database Syst Rev. 2005;(2):CD001002. PMID 15846609
↨ Reilly D, Taylor MA, Beattie NG, et al. Is evidence for homoeopathy reproducible? Lancet. 1994;344(8937):1601-6. PMID 7983994
↨ White A, Slade P, Hunt C, et al. Individualised homeopathy as an adjunct in the treatment of childhood asthma: a randomised placebo controlled trial. Thorax. 2003;58(4):317-21. PMID 12668794
↨ Nagendra HR, Nagarathna R. An integrated approach of yoga therapy for bronchial asthma: a 3-54-month prospective study. J Asthma. 1986;23(3):123-37. PMID 3745111
↨ Manocha R, Marks GB, Kenchington P, et al. Sahaja yoga in the management of moderate to severe asthma: a randomised controlled trial. Thorax. 2002;57(2):110-5. PMID 11828038
↨ Bowler SD, Green A, Mitchell CA. Buteyko breathing techniques in asthma: a blinded randomised controlled trial. Med J Aust. 1998;169(11-12):575-8. PMID 9887897
↨ Beckett PA, Howarth PH. Pharmacotherapy and airway remodelling in asthma? Thorax. 2003;58(2):163-74. PMID 12554904
↨ World Health Organization [homepage on the Internet]. Bronchial asthma: scope of the problem. Geneva: World Health Organization; ©2005. Available from http://www.who.int/entity/respiratory/asthma/scope/en/index.html. Accessed on 23 Aug 2005.
↨ Weiler JM, Layton T, Hunt M. Asthma in United States Olympic athletes who participated in the 1996 Summer Games. J Allergy Clin Immunol. 1998;102(5):722-6. PMID 9819287
↨ Helenius I, Haahtela T. Allergy and asthma in elite summer sport athletes. J Allergy Clin Immunol. 2000;106(3):444-52 PMID 10984362
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External links
Asthma UK - a user-friendly site with information on asthma and ways that UK residents can help improve asthma-related policy.
MedLinePlus: Asthma - a U.S. National Library of Medicine page.
National Heart, Lung, and Blood Institute — Asthma - U.S. NHLBI Information for Patients and the Public page.
National Heart, Lung, and Blood Institute — Asthma - U.S. NHLBI Information for Health Professionals page.
Case Studies in Environmental Medicine (CSEM) - Environmental Triggers of Asthma - a page from the Agency for Toxic Substances and Disease Registry, a service of the U.S. Department of Health and Human Services.
Retrieved from "http://en.wikipedia.org/wiki/Asthma"