| Asthma | |
|---|---|
| Classification and external resources | |
An asthma attack causes the airways to tighten and causes too much mucus to be made. This makes it hard to breathe. | |
| ICD-10 | J45. |
| ICD-9 | 493 |
| OMIM | 600807 |
| DiseasesDB | 1006 |
| MedlinePlus | 000141 |
| eMedicine | article/806890 |
| MeSH | D001249 |
Asthma (or asthma bronchiale) is an obstructive lung disease which affect the airways inside the lungs. It affects about 5-8 percent of the population. It has generally been accepted as an inflammatory disease.[verification needed] A person may have asthma or COPD. COPD may co-exist with asthma but usually people do not have both. COPD is generally a higher risk or more likely condition in people who are over 35 while asthma is usually discovered during childhood.
There are a lot of risk factors for getting asthma. The exact reasons for each is not yet clearly understood. Some of the factors are believed to come from genetics. A person inherits genetic mutations from one or both of their parents that may increase the chances of developing asthma. Epigenetics, which are changes in the way a gene acts, may also increase their chances of getting asthma. These epigenetic changes may also be inherited. They may happen when a baby is still growing inside its mother, or during childhood.
All asthma attacks can be a medical emergency because they can be fatal (cause a person to die). There is no cure for asthma. Especially dangerous attacks are called severe attacks. There are also more severe attacks than that, the most severe, called life-threatening attacks. There are treatments, such as different kinds of medicines to help people with asthma. There are also things that people with asthma can do to help themselves to keep their asthma from getting worse. Childhood (like in adolescents) asthma usually gets mostly better on its own with age.
Asthma causes the tissue inside the airways to swell. Asthmatics are affected in three ways by asthma, which cause the airway swelling. Asthma causes the bands of muscle (bronchial muscle) around the airways to become narrow. This makes it hard for enough air to pass through and for the person to breathe normally. It causes mucus-making cells inside the airways to make more mucus than normal. This blocks the airways, which are already very narrow during an asthma attack, and makes it even more difficult to breathe. Mucosal swelling or inflammation is caused by mast cell and basophil degranulation which makes the body produce more mucus as inflammatory mediators (things released in the body that cause inflammation).
A person having an asthma attack often makes wheezing sounds when trying to breathe. This is the sound of air trying to pass through the very narrow airway. They also have shortness of breath, which means they cannot take a full, deep breath. Chest tightness may happen which feels like their chest is being squeezed. They may also cough a lot.
Asthma can be caused by a lot of things, such as the home or work environment. If it is caused by something at work or home, then it might happen on a schedule, like when the person goes to work. Home furniture, like bedding, pets, animals, or plants, causing asthma or making it worse, is common. Asthma which flares up at night the most is called nocturnal asthma. An asthmatic cough often happens nocturnally (at night). There are other types of asthma. A person that has breathing problems might speak to a pulmonologist or asthma specialist (a doctor who specializes in asthma) about these to help track down the source and make it not as bad.
Socioeconomic status (SES) is also believed to play a part in developing asthma. A person's socioeconomic status is based on such things as how much money their family makes, where they live, and their education level. Race and ethnicity also may play a part. It also is related to access to medical care, personal beliefs, and dietary habits. People of lower socioeconomic status suffer higher rates of asthma, have worse outcomes, and also have higher asthma-related death rates than people of higher economic status.
The exact cause of asthma is not yet known. It is believed that it may be caused by:
If a person who has a genetic or epigenetic change or changes in their genes that gives them a chance of getting asthma (genetic predisposition), and has unhealthy environmental factors in their life (like living in a home that has a lot of dust mites) then it is more likely that they will get asthma.
Atopy is when there are changes in some of the genes a person is born with (genetic inheritance). These genetic changes make the body produce more Immunoglobulin E (IgE). IgE is a type of antibody. Atopic people are also more sensitive to things things like chemicals, smoke and dust (environmental antigens). This hypersensitivity means they are more sensitive or allergic to things in the environment than others, who do not have these changes in their genes and are not hypersensitive or allergic.
This hypersensitivity causes the body to react in certain ways. Usually a person who is atopic develops allergic rhinitis which affects the nasal passages, which are behind the nose. It also causes people with hypersensitivity to get atopic dermatitis, which causes skin rashes and atopic asthma. Up to 40% of people with allergic rhinitis also have asthma.
These three medical problems, being allergic rhinitis (hay fever), atopic dermatitis, and atopic asthmas are an atopic triad (a triad is when there is three of something). People who are atopic may also have other medical problems including food and drug allergies, stinging-insect hypersurtica, hives (urticaria) angioedemas edema (angioedema), and contact dermatitis.
If a person has one parent who is atopic they have a chance of being atopic too. If they have two parents who are atopic they have an even bigger chance of being atopic.

There have been studies that show a link between acetaminophen (Tylenol) and asthma. For instance a 2008 analysis of information collected from a very large study called the International Study of Asthma and Allergies in Childhood, or the "Isaac study" for short, showed that children who had taken acetaminophen for a fever during the first year of their life had a 50% higher risk of getting asthma later on. The more acetaminophen children took the higher their risk of getting asthma. Children who took it once a month had threefold increase in their risk of getting asthma. An increase in asthma rates in multiple countries corresponded with increased sales of drugs which contained acetaminophen. Previously the American College of Physicians reported a link between non-atopic asthma and acetaminophen use based on results of The Third National Health and Nutrition Examination Survey.
Atopic asthma is the most common form of asthma.
Cough-variant asthma is a type of asthma in which a cough is the main, and sometimes only sign. Cough-variant asthma usually does not cause wheezing or breathlessness and causes a dry, scratchy, mostly nonproductive cough (this means little or no phlegm is coughed up). About 30% of people who have cough-variant asthma will develop typical asthma.

Work related asthma are types of asthma that are caused or made worse by irritants in the environment at a person's place of work. The kind of jobs that may cause work related asthma are usually those in which there is a lot of smoke or chemicals are used. There are different types of work-related asthma (WRA), also called occupational asthma:
1. Occupational asthma with latency: this asthma type is when the signs and symptoms of asthma occur after a period of time (latency) after being exposed to the environmental irritants. e.g.: John starts working at a factory where chemicals are used the first week of January. At the end of March he starts developing the signs and symptoms of asthma. The period of time from when he started the job in January to when the signs and symptoms of asthma started in March is the latency period.
2. Irritant-Induced Asthma (IIA) is occupational asthma without latency: this is an asthma type is when the signs and symptoms of asthma can occur immediately (without latency) after being exposed to the environmental irritants. e.g. Frank starts a new job working as a janitor where he uses ammonia to clean. After opening the bottle of ammonia and breathing the fumes Frank starts finding it difficult to breath, his chest tightens up and he develops other signs and symptoms of asthma.
3. Reactive Airways Dysfunction Syndrome (RADS):
4. Work-aggravated asthma: this is when a person already has asthma and environmental triggers at their place of work makes it worse.
Exercise induced asthma (EIA) - also called exercise induced bronchospasm - is the term used to describe asthma cases in which exercise is the main, and many times the only trigger for an asthma attack. If a person already has a form of asthma or they are atopic there is more of a chance of getting EIA.
Nocturnal asthma is the term used to describe asthma cases that get worse at night (nocturnal). Doctors look out for the asthma being nocturnal, in addition to checking levels during work hours.
Premenstrual asthma (PMA): is when asthma symptoms get worse during the premenstrual period. This condition may affect up to 40% of female asthma sufferers. For a diagnosis of PMA to be made it is necessary to have a detailed history of the timing of menstrual cycles along with asthma symptoms experienced, and the peak expiratory flow rate (PMA may cause the PEF to be lowered in the premenstrual period). It is helpful in making a diagnosis to keep a diary of symptoms and peak expiratory flow (PEF) rates.
Status asthmaticus is a severe form of asthma in which an asthma attack gets worse as it goes along and the medicines that are usually used to treat asthma do not work. Status asthmaticus can be fatal.

Signs and symptoms in medicine are the way a medical condition affects a person's body. Sometimes the signs and symptoms of asthma may be mild which does not bother the person too much. At other times they may be severe which may make the person feel very sick.
Not every person with asthma has all the signs and symptoms of asthma all the time. A person may have some signs and symptoms during one asthma attack and have different symptoms during another asthma attack. Some people with asthma may have long periods of time between asthma attacks where they show no signs and experience no symptoms of asthma, while others may have some or all of the signs and symptoms everyday which become more severe during an attack. It also depends on what type of asthma a person has and whether they have a mild, moderate or severe case.
There are also some people with asthma who might only have signs and symptoms during certain times, such as those with exercise induced asthma, where the exercise triggers the symptoms. For some the signs and symptoms of asthma may be triggered or made worse (exacerbated) when they have viral respiratory tract infections, often the type caused by human rhinoviruses.
Early warning signs of an asthma attack are physical changes in health that a person with asthma has before they have the attack. By knowing the early warning signs a person may be able to take steps to keep from having an asthma attack or if they do have one, to keep it from getting worse.
The early warning signs of asthma may include:
A trigger factor or trigger for short, is something that causes the signs and symptoms of a medical condition to begin in a person who already has that medical condition. Common triggers for asthma are:
The best way to deal with asthma triggers is to learn what they are and avoid them if possible, and if not totally avoidable then adjust one's behavior to deal with them. Example: running on a cold winter day right up to the doorstep of a warm house and going immediately inside. The sudden temperature change can cause an attack and could have been avoided. In general but especially with a medical condition such as asthma it is necessary to be aware of one's environment and what's in it, both indoors and outdoors.
Most often the Asthma is triggered by allergens.One big source of allergens is the carpet. Totally replace it with a tiles floor reduce the possibility to create a good environment for the allergens and it is more simple to clean and disinfect.


An asthma attack is when, after a period of time when a person has had only a few or no symptoms of asthma, the asthma gets worse all of a sudden, usually because of being exposed to one or more triggers. When the asthma attack happens, the tissue inside the airways swell because of inflammation, which is how the body tries to protect itself from harmful things, like germs and irritants. When the tissues swell the opening (called the lumen) in the airway gets very narrow.
The smooth muscles (which are the kind of muscles in the body that do not contract voluntarily, like the ones in the arm) around the bronchi and bronchioles begin to spasm or contract which makes the opening in the airway even narrower. This is called a bronchospasm.
Inside the lining of the airways are glands called, submucosal glands, and above them, closer to the opening in the airway are cells called goblet cells - because they are shaped kind of like a goblet, which is a type of cup. The submucosal glands and the goblet cells make mucous which helps protect the inside of the airways. The mucous in the airways of healthy lungs is a thin film which traps irritants such as dust particles and pollen so they do not damage the airways and keep them from entering the air sacs (alveoli).
There are tiny hairs lining the airway called cilia. The cilia wave back and forth like a liitle whips, and help push the mucous and the trapped particles up the airways to the pharynx. From there the mucous, the trapped particles from the lower airways can be coughed up (called sputum).
During an asthma attack the submucosal glands and the goblet cells start making much more mucous than normal, and the mucous is also thicker than normal. This makes it very hard for the cilia to do their job, and bring the mucous up out of the airways. So now there is too much mucous being made, and not enough being brought up by the cilia. The airways are already to narrow to breathe properly because of the tissue swelling caused by inflammation and the constriction caused by the bronchospasms, so the extra mucous blocks the airway even more. This makes breathing very difficult. In fatal asthma attacks the airways can become so constricted and/or plugged with mucous that no air can get through at all.
There are other signs of breathing difficulty as in an asthma attack, which are important to learn, and knowing them can help tell if someone who cannot talk is having breathing problems. People who may not be able to let somebody know they are having breathing problems include babies and young children.
Some of the other signs of asthma includeː
A diagnosis of asthma is based on:
There is no specific test that can tell if a person has asthma, however there are tests that can help in the diagnosis when the results are considered along with the medical and family history and physical exam
Differential diagnoses are different medical disorders which may cause the same symptoms. Before a doctor makes a final diagnosis, which means they are sure of what medical disorder is causing the problem, they think of what other medical conditions have the same or almost the same symptoms, and make sure that it is not one of them.
The differential diagnoses of asthma include:

Airway remodelling is when there are permanent physical changes to the airways that also affects how they work. This may happen after chronic long-term asthma. After cycles of inflammation, damage and repair to the airways. permanent remodelling of the airways might happen. This is when the physical structure of the airway changes. This will cause permanent airway narrowing (they are always more narrow than normal and get narrower during an asthma attack), bronchospasms are more easily triggered (bronchial hyperresponsiveness), airway edema (fluid in the airway), and mucus hypersecretion (too much mucous is made) as well as the build-up of collagen around the airway which is called fibrosis. Airway remodeling has been observed in children as young as six.
Not managing asthma properly can lead to airway remodelling and this can increase the risk of dying from an asthma attack. One of the main problems which cause poor asthma management is not using the asthma inhaler correctly. One of the main reasons for improper inhaler use is the asthma patient not having the proper knowledge in using the inhaler due to not receiving proper instruction.
Among the physical changes that may happen in airway remodeling is goblet cell hyperplasia and submucosal gland hyperplasia. Submucosal glands and goblet cells make mucous which helps to protect the airways by trapping harmful particles like dust and pollen. The mucous is normally a thin film which lines the airways. The mucous and whatever particles they trap are brought up to the pharynx by tiny (microscopic) hairs on the inside of the airway that move back and forth called cilia.
During an asthma attack the submucosal glands and goblet cells make too much mucous, and it is thicker than normal which makes it harder for the cilia to bring the mucous up. When airway remodeling happens the body may make many more submucosal glands and goblet cells than normal, which means even more mucous is made. There may be too much mucous for the cilia to bring up and the airway may become blocked. This is one of the reasons that people with airway remodeling often have more severe asthma. In fatal cases the airway may have become totally plugged causing asphyxia.
Regular Breastfeeding sessions are a proven benefit to airway reconstruction. While previous studies have shown a similar effect between breastfeeding and asthma risk, this research is the first that showed a link between the length of breastfeeding and the number of wheezing episodes.[source?] Also, this study found evidence that the first asthma-related symptoms occur earlier in life if children were breastfed for shorter lengths of time or not exclusively. The study shows it’s not the nutritional benefit from the liquid, it’s the pull on lung of which dilates the smooth muscles of the air passage. Dry-nursing has actually proven to had been more beneficial in this study for strengthening airway health in both children and adults. Dilating the airways will strengthen them and the lungs themselves.
Asthma can be controlled most often by avoiding contact with triggers and by using certain drugs. Most asthma sufferers carry special medicines around with them. These are called inhalers. The medicine inside the inhaler opens the tubes that go to the lungs. The inhaler is usually used to prevent an asthma attack, or to stop an attack that is already happening.
A rescue medicine is an inhaler ("puffer") that is used if a person thinks they are having an asthma attack.
A controller medicine is a medicine in either a pill or an inhaler taken every day to prevent asthma attacks.
Hospitals have other options they can use in an emergency when the regular treatments don't work:
There are certain types of drugs that make asthma worse or that can trigger such an attack. Certain types of drugs should only be used in very specific situations. Some of these drugs are:
Aspirin (an NSAID) can make asthma worse. People may be allergic to aspirin, and also have a higher risk of becoming allergic even if they have not used it before. It also comes suddenly (sudden onset), coming in adulthood around 20 to 50 years old. Aspirin-exacerbated respiratory disease (AERD) is asthma getting worse (exacerbation) or their attacks being worse, caused by aspirin. AERD is part of a triad known as Samter's triad. Aspirin-induced asthma usually happens when coming into contact with aspirin or one of the other NSAIDs which inhibit the same enzyme as aspirin, for example by eating or inhaling them.
Samter's triad includes asthma, alongside sinus disease with nasal polyps that keep happening (recurrent polyps) and allergic reactions (sensitivity) to aspirin and other NSAIDs. The specific NSAIDs are ones that inhibit an enzyme called cyclooxygenase-1 (COX-1), which aspirin does. The exact reason why this happens is unknown.
Depression and anxiety have a negative impact on asthma. Comorbid anxiety with asthma is particularly confusing because of the similarity of symptoms and interference in perception and treatment of asthma. The National Asthma Council Australia recommends treatment for comorbid psychological symptoms. Cognitive Behavior Therapy (CBT) is one recommended treatment for anxiety and depression. There is tentative research evidence suggesting that a program of CBT amended for asthma, delivered in conjunction with medical treatment and in close liaison with your medical team, can improve anxiety, asthma and quality of life. Clinicians intending to deliver CBT for comorbid asthma, anxiety or depression should refer to and the research reviewed by for guidance on safe and effective intervention.
The global Initiative for Asthma (GINA), launched in 1993, is a collaborative effort between the World Health Organization (WHO), the National Institutes of Health USA (NIH), and the National Heart, Lung and Blood Institute. Its aims include; to increase public awareness of asthma, encourage research into the causes for the increasing prevalence of asthma worldwide, encourage research into the links between asthma and environmental factors, improve the effectiveness of asthma management practices, reduce the mortality and morbidity rates associated with asthma, and make treatments for asthma more readily available.
One of the ways in which GINA fulfils these aims is by producing medical guidelines on the management of asthma, which based on a systematically conducted review of the most recent-worldwide literature. These guidelines are free and available to all patients and clinicians from the GINA website. The GINA main report is updated annually and aims to reflect evolving best practice as it highlights changes in asthma management strategies.
GINA established ‘World Asthma Day’ in 1998, with the first event organized in Barcelona, Spain. It is held annually on the first Tuesday of May, and includes the participation of more than 35 countries.
Often, having one medical problem makes it more likely a person will also have one or more other medical or psychiatric problems. These other disorders are the "comorbid problems" or "comorbidities". There are various comorbid medical and psychiatric conditions associated with asthma.

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>10.1
7.6-10.0
5.1—7.5
2.5-5.0
0-2.5
no data: for these areas there was not enough information.
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In medicine, epidemiology is the study of what causes diseases and medical conditions, how often they happen, where they happen and who they happen to.
It is more common in developed countries than developing countries. The United States and Canada have some of the highest asthma rates in the world even though they are not poor countries. In Africa the country of South Africa has the highest asthma rate on the whole continent even though it is one of the richest countries.
More than 80% of the people who die from asthma are usually from low and middle income countries, but not always, as South Africa has the fourth highest death rate in the world even though it is one of the richer countries in the world. In the United States the death rates are higher for females, adults and people of African descent.
As of 2011, 235–300 million people worldwide are affected by asthma, and approximately 250,000 people die per year from the disease. Rates vary between countries with prevalence between 1 and 18%.
The amount of asthma cases reported each year has gotten much higher between the 1960s and 2008 Rates of asthma have plateaued in the developed world since the mid-1990s with recent increases primarily in the developing world. Asthma affects approximately 7% of the population of the United States and 5% of people in the United Kingdom. Canada, Australia and New Zealand have rates of about 14–15%.