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92-580: The American Asthma Foundation ( AAF ) was a non-profit grant program that funds basic research focused on asthma . Its stated mission is to improve treatments for, prevent, and find a cure for asthma. Established in 1999, it is the largest private funder of asthma research, having awarded over $ 110,000,000 in grant funds to 182 scientists. It suspended its operations in 2019. The American Asthma Foundation employed an unusual strategy to advance basic research in asthma: nearly all AAF grant funding has supported scientists who never before studied asthma. The concept

184-497: A beneficial effect. Other important or common causes of shortness of breath include cardiac tamponade , anaphylaxis , interstitial lung disease , panic attacks , and pulmonary hypertension . It is more common among people with relatively small lungs. Around 2/3 of women experience shortness of breath as a part of a normal pregnancy . Cardiac tamponade presents with dyspnea, tachycardia, elevated jugular venous pressure, and pulsus paradoxus . The gold standard for diagnosis

276-576: A cause of dyspnea. Menstruation, particularly if excessive, can contribute to anaemia and to consequential dyspnea in women. Headaches are a symptom of dyspnea in patients with anaemia. Some patients report a numb sensation in their head, and others have reported blurred vision caused by hypotension behind the eye due to a lack of oxygen and pressure; these patients have reported severe head pains, which can lead to permanent brain damage. Symptoms can include loss of concentration, focus, fatigue, language faculty impairment, and memory loss. Shortness of breath

368-433: A chronic productive cough. An acute exacerbation presents with increased shortness of breath and sputum production. COPD is a risk factor for pneumonia ; thus this condition should be ruled out. In an acute exacerbation treatment is with a combination of anticholinergics , beta 2 -adrenoceptor agonists , steroids and possibly positive pressure ventilation . Asthma is the most common reason for presenting to

460-406: A combination of factors, including poor treatment adherence, increased allergen and viral exposure, and altered immune tolerance. There is limited evidence to guide possible approaches to reducing autumn exacerbations, but while costly, seasonal omalizumab treatment from four to six weeks before school return may reduce autumn asthma exacerbations. Asthma is the result of chronic inflammation of

552-456: A common cause of acute attacks in women and children. Both viral and bacterial infections of the upper respiratory tract can worsen the disease. Psychological stress may worsen symptoms – it is thought that stress alters the immune system and thus increases the airway inflammatory response to allergens and irritants. Asthma exacerbations in school-aged children peak in autumn, shortly after children return to school. This might reflect

644-596: A fan may possibly be beneficial. Cognitive behavioural therapy may also be helpful. For people with severe, chronic, or uncontrollable breathlessness, non-pharmacological approaches to treating breathlessness may be combined with medication. For people who have cancer that is causing the breathlessness, medications that have been suggested include opioids, benzodiazepines, oxygen, and steroids. Results of recent systematic reviews and meta-analyses found opioids were not necessarily associated with more effectiveness in treatment for patients with advanced cancer. Ensuring that

736-804: A fever, dry cough, loss of smell and taste, and in moderate to severe cases, shortness of breath. Congestive heart failure frequently presents with shortness of breath with exertion, orthopnea , and paroxysmal nocturnal dyspnea . It affects between 1 and 2% of the general United States population and occurs in 10% of those over 65 years old. Risk factors for acute decompensation include high dietary salt intake, medication noncompliance, cardiac ischemia, abnormal heart rhythms , kidney failure , pulmonary emboli, hypertension , and infections. Treatment efforts are directed towards decreasing lung congestion. People with chronic obstructive pulmonary disease (COPD), most commonly emphysema or chronic bronchitis , frequently have chronic shortness of breath and

828-413: A few times a day or a few times per week. Depending on the person, asthma symptoms may become worse at night or with exercise. Asthma is thought to be caused by a combination of genetic and environmental factors . Environmental factors include exposure to air pollution and allergens . Other potential triggers include medications such as aspirin and beta blockers . Diagnosis is usually based on

920-522: A large pulmonary embolism. A chest x-ray is useful to confirm or rule out a pneumothorax, pulmonary edema , or pneumonia . Spiral computed tomography with intravenous radiocontrast is the imaging study of choice to evaluate for pulmonary embolism. The primary treatment of shortness of breath is directed at its underlying cause. Extra supplemental oxygen is effective in those with hypoxia ; however, this has no effect in those with normal blood oxygen saturations . Individuals can benefit from

1012-463: A pathophysiological basis the causes can be divided into: (1) an increased awareness of normal breathing such as during an anxiety attack, (2) an increase in the work of breathing and (3) an abnormality in the ventilatory or respiratory system. Ischemic strokes, hemorrhages, tumors, infections, seizures, and traumas at the brain stem can also cause shortness of breath, making them the only neurological causes of shortness of breath. The tempo of onset and

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1104-412: A person's asthma is controlled. The methacholine challenge involves the inhalation of increasing concentrations of a substance that causes airway narrowing in those predisposed. If negative it means that a person does not have asthma; if positive, however, it is not specific for the disease. Other supportive evidence includes: a ≥20% difference in peak expiratory flow rate on at least three days in

1196-405: A pulmonary embolism in those who are at low risk, is not of much value if it is positive, as it may be positive in a number of conditions that lead to shortness of breath. A low level of brain natriuretic peptide is useful in ruling out congestive heart failure; however, a high level, while supportive of the diagnosis, could also be due to advanced age, kidney failure , acute coronary syndrome, or

1288-454: A result of vocal cord dysfunction (VCD). Sarcoidosis is an inflammatory disease of unknown etiology that generally presents with dry cough, fatigue, and shortness of breath, although multiple organ systems may be affected, with involvement of sites such as the eyes, the skin and the joints. Different physiological pathways may lead to shortness of breath including via ASIC chemoreceptors , mechanoreceptors , and lung receptors . It

1380-413: A significantly higher risk compared to randomly selected controls ( odds ratio 7.2, 95% confidence interval 5.2–10). Asthma phenotyping and endotyping has emerged as a novel approach to asthma classification inspired by precision medicine which separates the clinical presentations of asthma, or asthma phenotypes, from their underlying causes, or asthma endotypes. The best-supported endotypic distinction

1472-585: A third of people. This may be even more common in some ethnic groups such as the Japanese and those with aspirin-exacerbated respiratory disease. Other studies have found improvement in asthmatic symptoms from alcohol. Non-atopic asthma, also known as intrinsic or non-allergic, makes up between 10 and 33% of cases. There is negative skin test to common inhalant allergens. Often it starts later in life, and women are more commonly affected than men. Usual treatments may not work as well. The concept that "non-atopic"

1564-429: A trigger for asthma; formaldehyde exposure, for example, has a positive association. Phthalates in certain types of PVC are associated with asthma in both children and adults. While exposure to pesticides is linked to the development of asthma, a cause and effect relationship has yet to be established. A meta-analysis concluded gas stoves are a major risk factor for asthma, finding around one in eight cases in

1656-592: A variety of physical therapy interventions. Persons with neurological/neuromuscular abnormalities may have breathing difficulties due to weak or paralyzed intercostal, abdominal and/or other muscles needed for ventilation . Some physical therapy interventions for this population include active assisted cough techniques, volume augmentation such as breath stacking, education about body position and ventilation patterns and movement strategies to facilitate breathing. Pulmonary rehabilitation may alleviate symptoms in some people, such as those with COPD, but will not cure

1748-432: A week for at least two weeks, a ≥20% improvement of peak flow following treatment with either salbutamol, inhaled corticosteroids or prednisone, or a ≥20% decrease in peak flow following exposure to a trigger. Testing peak expiratory flow is more variable than spirometry, however, and thus not recommended for routine diagnosis. It may be useful for daily self-monitoring in those with moderate to severe disease and for checking

1840-405: Is / d ɪ s p ˈ n iː ə / disp- NEE -ə , with the p expressed and the stress on the /niː/ syllable. But pronunciations with a silent p in pn (as also in pneumo- ) are common ( / d ɪ s ˈ n iː ə / or / ˈ d ɪ s n i ə / ), as are those with the stress on the first syllable ( / ˈ d ɪ s p n i ə / or / ˈ d ɪ s n i ə / ). In English,

1932-409: Is ultrasound . Anaphylaxis typically begins over a few minutes in a person with a previous history of the same. Other symptoms include urticaria , throat swelling , and gastrointestinal upset. The primary treatment is epinephrine . Interstitial lung disease presents with gradual onset of shortness of breath typically with a history of a predisposing environmental exposure. Shortness of breath

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2024-1016: Is a commonly reported occupational disease . Many cases, however, are not reported or recognized as such. It is estimated that 5–25% of asthma cases in adults are work-related. A few hundred different agents have been implicated, with the most common being isocyanates , grain and wood dust, colophony , soldering flux , latex , animals, and aldehydes . The employment associated with the highest risk of problems include those who spray paint , bakers and those who process food, nurses, chemical workers, those who work with animals, welders , hairdressers and timber workers. Aspirin-exacerbated respiratory disease (AERD), also known as aspirin -induced asthma, affects up to 9% of asthmatics. AERD consists of asthma, nasal polyps, sinus disease, and respiratory reactions to aspirin and other NSAID medications (such as ibuprofen and naproxen). People often also develop loss of smell and most experience respiratory reactions to alcohol. Alcohol may worsen asthmatic symptoms in up to

2116-429: Is a history of atopic disease ; with asthma occurring at a much greater rate in those who have either eczema or hay fever . Asthma has been associated with eosinophilic granulomatosis with polyangiitis (formerly known as Churg–Strauss syndrome), an autoimmune disease and vasculitis . Individuals with certain types of urticaria may also experience symptoms of asthma. There is a correlation between obesity and

2208-456: Is a kind of asthma distinguishable by recurrent, severe attacks. Type 1 brittle asthma is a disease with wide peak flow variability, despite intense medication. Type 2 brittle asthma is background well-controlled asthma with sudden severe exacerbations. Exercise can trigger bronchoconstriction both in people with or without asthma. It occurs in most people with asthma and up to 20% of people without asthma. Exercise-induced bronchoconstriction

2300-570: Is a lack of evidence to recommend midazolam , nebulised opioids, the use of gas mixtures, or cognitive-behavioral therapy yet. Non-pharmacological interventions provide key tools for the management of breathlessness. Potentially beneficial approaches include active management of psychosocial issues ( anxiety , depression , etc.), and implementation of self-management strategies, such as physical and mental relaxation techniques , pacing techniques, energy conservation techniques, learning exercises to control breathing, and education . The use of

2392-503: Is a specific single nucleotide polymorphism in the CD14 region and exposure to endotoxin (a bacterial product). Endotoxin exposure can come from several environmental sources including tobacco smoke, dogs, and farms. Risk for asthma, then, is determined by both a person's genetics and the level of endotoxin exposure. A triad of atopic eczema , allergic rhinitis and asthma is called atopy. The strongest risk factor for developing asthma

2484-499: Is a well-recognized condition, there is not one universal agreed-upon definition. It is defined by the Global Initiative for Asthma as "a chronic inflammatory disorder of the airways in which many cells and cellular elements play a role. The chronic inflammation is associated with airway hyper-responsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness and coughing particularly at night or in

2576-732: Is affected, the probability of the other having the disease is approximately 25%. By the end of 2005, 25 genes had been associated with asthma in six or more separate populations, including GSTM1 , IL10 , CTLA-4 , SPINK5 , LTC4S , IL4R and ADAM33 , among others. Many of these genes are related to the immune system or modulating inflammation. Even among this list of genes supported by highly replicated studies, results have not been consistent among all populations tested. In 2006 over 100 genes were associated with asthma in one genetic association study alone; more continue to be found. Some genetic variants may only cause asthma when they are combined with specific environmental exposures. An example

2668-594: Is associated with a greater risk of asthma-like symptoms. Low air quality from environmental factors such as traffic pollution or high ozone levels has been associated with both asthma development and increased asthma severity. Over half of cases in children in the United States occur in areas when air quality is below the EPA standards. Low air quality is more common in low-income and minority communities. Exposure to indoor volatile organic compounds may be

2760-500: Is associated with an increased risk of asthma in the child. Some individuals will have stable asthma for weeks or months and then suddenly develop an episode of acute asthma. Different individuals react to various factors in different ways. Most individuals can develop severe exacerbation from a number of triggering agents. Home factors that can lead to exacerbation of asthma include dust , animal dander (especially cat and dog hair), cockroach allergens and mold . Perfumes are

2852-504: Is associated with exposure to indoor allergens. Common indoor allergens include dust mites , cockroaches , animal dander (fragments of fur or feathers), and mould. Efforts to decrease dust mites have been found to be ineffective on symptoms in sensitized subjects. Weak evidence suggests that efforts to decrease mould by repairing buildings may help improve asthma symptoms in adults. Certain viral respiratory infections, such as respiratory syncytial virus and rhinovirus , may increase

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2944-435: Is attributed to the lack of healthy bacterial colonization that the newborn would have acquired from passage through the birth canal. There is a link between asthma and the degree of affluence which may be related to the hygiene hypothesis as less affluent individuals often have more exposure to bacteria and viruses. Family history is a risk factor for asthma, with many different genes being implicated. If one identical twin

3036-977: Is believed that the recent increased rates of asthma are due to changing epigenetics ( heritable factors other than those related to the DNA sequence ) and a changing living environment. Asthma that starts before the age of 12 years old is more likely due to genetic influence, while onset after age 12 is more likely due to environmental influence. Many environmental factors have been associated with asthma's development and exacerbation, including allergens, air pollution, and other environmental chemicals. There are some substances that are known to cause asthma in exposed people and they are called asthmagens . Some common asthmagens include ammonia, latex, pesticides, solder and welding fumes, metal or wood dusts, spraying of isocyanate paint in vehicle repair, formaldehyde, glutaraldehyde, anhydrides, glues, dyes, metal working fluids, oil mists, moulds. Smoking during pregnancy and after delivery

3128-427: Is classified based on severity, at the moment there is no clear method for classifying different subgroups of asthma beyond this system. Finding ways to identify subgroups that respond well to different types of treatments is a current critical goal of asthma research. Recently, asthma has been classified based on whether it is associated with type 2 or non–type 2 inflammation. This approach to immunologic classification

3220-626: Is common in people with cancer and may be caused by numerous different factors. In people with advanced cancer, periods of time with severe shortness of breath may occur, along with a more continuous feeling of breathlessness. Treatments include both nonpharmacological and pharmacological interventions. Nonpharmacological interventions that showed improvement in breathlessness include fans, behavioral and pyschoeducational approaches, exercise and pulmonary rehabilitation. Integrative medicine options include acupuncture/acupressure/reflexology, meditation and music therapy, with acupuncture/reflexology found to have

3312-437: Is common in professional athletes. The highest rates are among cyclists (up to 45%), swimmers, and cross-country skiers. While it may occur with any weather conditions, it is more common when it is dry and cold. Inhaled beta 2 agonists do not appear to improve athletic performance among those without asthma; however, oral doses may improve endurance and strength. Asthma as a result of (or worsened by) workplace exposures

3404-464: Is commonly referred to as an asthma attack . The classic symptoms are shortness of breath , wheezing , and chest tightness . The wheezing is most often when breathing out. While these are the primary symptoms of asthma, some people present primarily with coughing , and in severe cases, air motion may be significantly impaired such that no wheezing is heard. In children, chest pain is often present. Signs occurring during an asthma attack include

3496-430: Is correlated with more exposure to cigarette smoke, an older age, less symptom reversibility after bronchodilator administration, and decreased likelihood of family history of atopy. The evidence for the effectiveness of measures to prevent the development of asthma is weak. The World Health Organization recommends decreasing risk factors such as tobacco smoke, air pollution, chemical irritants including perfume , and

3588-436: Is driven by a developing understanding of the underlying immune processes and by the development of therapeutic approaches that target type 2 inflammation. Although asthma is a chronic obstructive condition, it is not considered as a part of chronic obstructive pulmonary disease , as this term refers specifically to combinations of disease that are irreversible such as bronchiectasis and emphysema . Unlike these diseases,

3680-399: Is insufficient, the use of medication is recommended. Pharmaceutical drugs are selected based on, among other things, the severity of illness and the frequency of symptoms. Specific medications for asthma are broadly classified into fast-acting and long-acting categories. The medications listed below have demonstrated efficacy in improving asthma symptoms; however, real world use-effectiveness

3772-537: Is limited as around half of people with asthma worldwide remain sub-optimally controlled, even when treated. People with asthma may remain sub-optimally controlled either because optimum doses of asthma medications do not work (called "refractory" asthma) or because individuals are either unable (e.g. inability to afford treatment, poor inhaler technique) or unwilling (e.g., wish to avoid side effects of corticosteroids) to take optimum doses of prescribed asthma medications (called "difficult to treat" asthma). In practice, it

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3864-408: Is no known cure for asthma, but it can be controlled. Symptoms can be prevented by avoiding triggers, such as allergens and respiratory irritants , and suppressed with the use of inhaled corticosteroids . Long-acting beta agonists (LABA) or antileukotriene agents may be used in addition to inhaled corticosteroids if asthma symptoms remain uncontrolled. Treatment of rapidly worsening symptoms

3956-434: Is not known whether asthma causes psychological problems or psychological problems lead to asthma. Current asthma, but not former asthma, is associated with increased all-cause mortality, heart disease mortality, and chronic lower respiratory tract disease mortality. Asthma, particularly severe asthma, is strongly associated with development of chronic obstructive pulmonary disease (COPD). Those with asthma, especially if it

4048-452: Is not possible to distinguish "refractory" from "difficult to treat" categories for patients who have never taken optimum doses of asthma medications. A related issue is that the asthma efficacy trials upon which the pharmacological treatment guidelines are based have systematically excluded the majority of people with asthma. For example, asthma efficacy treatment trials always exclude otherwise eligible people who smoke, and smoking diminishes

4140-479: Is often the only symptom in those with tachydysrhythmias . Panic attacks typically present with hyperventilation , sweating, and numbness . They are however a diagnosis of exclusion . Neurological conditions such as spinal cord injury, phrenic nerve injuries, Guillain–Barré syndrome , amyotrophic lateral sclerosis , multiple sclerosis and muscular dystrophy can all cause an individual to experience shortness of breath. Shortness of breath can also occur as

4232-399: Is often used to assess the clinical probability. Treatment, depending on severity of symptoms, typically starts with anticoagulants ; the presence of ominous signs (low blood pressure) may warrant the use of thrombolytic drugs . Anemia that develops gradually usually presents with exertional dyspnea, fatigue, weakness, and tachycardia . It may lead to heart failure . Anaemia is often

4324-478: Is poorly controlled, are at increased risk for radiocontrast reactions. Cavities occur more often in people with asthma. This may be related to the effect of beta 2 -adrenergic agonists decreasing saliva. These medications may also increase the risk of dental erosions . Asthma is caused by a combination of complex and incompletely understood environmental and genetic interactions. These influence both its severity and its responsiveness to treatment. It

4416-421: Is supportive of the diagnosis. It however may be normal in those with a history of mild asthma, not currently acting up. As caffeine is a bronchodilator in people with asthma, the use of caffeine before a lung function test may interfere with the results. Single-breath diffusing capacity can help differentiate asthma from COPD . It is reasonable to perform spirometry every one or two years to follow how well

4508-412: Is synonymous with "non-allergic" is called into question by epidemiological data that the prevalence of asthma is closely related to the serum IgE level standardized for age and sex (P<0.0001), indicating that asthma is almost always associated with some sort of IgE-related reaction and therefore has an allergic basis, although not all the allergic stimuli that cause asthma appear to have been included in

4600-876: Is the primary reason 3.5% of people present to the emergency department in the United States. Of these individuals, approximately 51% are admitted to the hospital and 13% are dead within a year. Some studies have suggested that up to 27% of hospitalized people develop dyspnea, while in dying patients 75% will experience it. Acute shortness of breath is the most common reason people requiring palliative care visit an emergency department. Up to 70% of adults with advanced cancer also experience dyspnoea. English dyspnea comes from Latin dyspnoea , from Greek dyspnoia , from dyspnoos , which literally means "disordered breathing". Its combining forms ( dys- + -pnea ) are familiar from other medical words, such as dysfunction ( dys- + function ) and apnea ( a- + -pnea ). The most common pronunciation in medical English

4692-722: Is the type 2-high/type 2-low distinction. Classification based on type 2 inflammation is useful in predicting which patients will benefit from targeted biologic therapy . Many other conditions can cause symptoms similar to those of asthma. In children, symptoms may be due to other upper airway diseases such as allergic rhinitis and sinusitis , as well as other causes of airway obstruction including foreign body aspiration , tracheal stenosis , laryngotracheomalacia , vascular rings , enlarged lymph nodes or neck masses. Bronchiolitis and other viral infections may also produce wheezing. According to European Respiratory Society , it may not be suitable to label wheezing preschool children with

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4784-482: Is then used to confirm the diagnosis. In children under the age of six the diagnosis is more difficult as they are too young for spirometry. Spirometry is recommended to aid in diagnosis and management. It is the single best test for asthma. If the FEV 1 measured by this technique improves more than 12% and increases by at least 200 millilitres following administration of a bronchodilator such as salbutamol , this

4876-473: Is thought that three main components contribute to dyspnea: afferent signals, efferent signals, and central information processing. It is believed the central processing in the brain compares the afferent and efferent signals; and dyspnea results when a "mismatch" occurs between the two: such as when the need for ventilation (afferent signaling) is not being met by physical breathing (efferent signaling). Afferent signals are sensory neuronal signals that ascend to

4968-423: Is usually with an inhaled short-acting beta 2 agonist such as salbutamol and corticosteroids taken by mouth. In very severe cases, intravenous corticosteroids, magnesium sulfate , and hospitalization may be required. In 2019 asthma affected approximately 262 million people and caused approximately 461,000 deaths. Most of the deaths occurred in the developing world . Asthma often begins in childhood, and

5060-414: The conducting zone of the airways (most especially the bronchi and bronchioles ), which subsequently results in increased contractability of the surrounding smooth muscles . This among other factors leads to bouts of narrowing of the airway and the classic symptoms of wheezing. The narrowing is typically reversible with or without treatment. Occasionally the airways themselves change. Typical changes in

5152-421: The respiratory muscles . The most important respiratory muscle is the diaphragm . Other respiratory muscles include the external and internal intercostal muscles , the abdominal muscles and the accessory breathing muscles. As the brain receives its plentiful supply of afferent information relating to ventilation, it is able to compare it to the current level of respiration as determined by the efferent signals. If

5244-423: The "infectious asthma" (IA) syndrome, or as "asthma associated with infection" (AAWI) to distinguish infection-associated asthma initiation from the well known association of respiratory infections with asthma exacerbations. Reported clinical prevalences of IA for adults range from around 40% in a primary care practice to 70% in a speciality practice treating mainly severe asthma patients. Additional information on

5336-708: The American Asthma Foundation suspended funding for new grants in 2019. Asthma Asthma is a common long-term inflammatory disease of the airways of the lungs . Asthma occurs when allergens , pollen , dust, or other particles, are inhaled into the lungs, causing the bronchioles to constrict and produce mucus, which then restricts oxygen flow to the alveoli . It is characterized by variable and recurring symptoms, reversible airflow obstruction , and easily triggered bronchospasms . Symptoms include episodes of wheezing , coughing , chest tightness, and shortness of breath . These may occur

5428-433: The U.S. could be attributed to these. The majority of the evidence does not support a causal role between paracetamol (acetaminophen) or antibiotic use and asthma. A 2014 systematic review found that the association between paracetamol use and asthma disappeared when respiratory infections were taken into account. Maternal psychological stress during pregnancy is a risk factor for the child to develop asthma. Asthma

5520-471: The age of 65, most people with obstructive airway disease will have asthma and COPD. In this setting, COPD can be differentiated by increased airway neutrophils, abnormally increased wall thickness, and increased smooth muscle in the bronchi. However, this level of investigation is not performed due to COPD and asthma sharing similar principles of management: corticosteroids, long-acting beta-agonists, and smoking cessation. It closely resembles asthma in symptoms,

5612-616: The airway obstruction in asthma is usually reversible; however, if left untreated, the chronic inflammation from asthma can lead the lungs to become irreversibly obstructed due to airway remodelling. In contrast to emphysema, asthma affects the bronchi, not the alveoli . The combination of asthma with a component of irreversible airway obstruction has been termed the asthma-chronic obstructive disease (COPD) overlap syndrome (ACOS) . Compared to other people with "pure" asthma or COPD, people with ACOS exhibit increased morbidity, mortality and possibly more comorbidities. An acute asthma exacerbation

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5704-466: The airways include an increase in eosinophils and thickening of the lamina reticularis . Chronically the airways' smooth muscle may increase in size along with an increase in the numbers of mucous glands. Other cell types involved include T lymphocytes , macrophages , and neutrophils . There may also be involvement of other components of the immune system , including cytokines , chemokines , histamine , and leukotrienes among others. While asthma

5796-414: The balance between side effects and adverse effects from medications and potential improvements from medications needs to be carefully considered before prescribing medication. The use of systematic corticosteriods in palliative care for people with cancer is common, however the effectiveness and potential adverse effects of this approach in adults with cancer has not been well studied. Shortness of breath

5888-575: The battery of aeroallergens studied (the "missing antigen(s)" hypothesis). For example, an updated systematic review and meta-analysis of population-attributable risk (PAR) of Chlamydia pneumoniae biomarkers in chronic asthma found that the PAR for C. pneumoniae -specific IgE was 47%. Infectious asthma is an easily identified clinical presentation. When queried, asthma patients may report that their first asthma symptoms began after an acute lower respiratory tract illness. This type of history has been labelled

5980-450: The brain. Afferent neurons significant in dyspnea arise from a large number of sources including the carotid bodies , medulla , lungs , and chest wall . Chemoreceptors in the carotid bodies and medulla supply information regarding the blood gas levels of O 2 , CO 2 and H . In the lungs, juxtacapillary (J) receptors are sensitive to pulmonary interstitial edema, while stretch receptors signal bronchoconstriction. Muscle spindles in

6072-461: The breath. It however may atypically present with shortness of breath alone. Risk factors include old age, smoking , hypertension , hyperlipidemia , and diabetes . An electrocardiogram and cardiac enzymes are important both for diagnosis and directing treatment. Treatment involves measures to decrease the oxygen requirement of the heart and efforts to increase blood flow. People that have been infected by COVID-19 may have symptoms such as

6164-434: The chest wall signal the stretch and tension of the respiratory muscles. Thus, poor ventilation leading to hypercapnia , left heart failure leading to interstitial edema (impairing gas exchange), asthma causing bronchoconstriction (limiting airflow) and muscle fatigue leading to ineffective respiratory muscle action could all contribute to a feeling of dyspnea. Efferent signals are the motor neuronal signals descending to

6256-865: The chest, jugular venous distension , and tracheal deviation. The symptoms of pneumonia are fever , productive cough , shortness of breath, and pleuritic chest pain . Inspiratory crackles may be heard on exam. A chest x-ray can be useful to differentiate pneumonia from congestive heart failure . As the cause is usually a bacterial infection, antibiotics are typically used for treatment. Pulmonary embolism classically presents with an acute onset of shortness of breath. Other presenting symptoms include pleuritic chest pain , cough, hemoptysis , and fever . Risk factors include deep vein thrombosis , recent surgery, cancer , and previous thromboembolism . It must always be considered in those with acute onset of shortness of breath owing to its high risk of mortality. Diagnosis, however, may be difficult and Wells Score

6348-431: The clinical prevalence of IA in adult-onset asthma is unavailable because clinicians are not trained to elicit this type of history routinely, and recollection in child-onset asthma is challenging. A population-based incident case-control study in a geographically defined area of Finland reported that 35.8% of new-onset asthma cases had experienced acute bronchitis or pneumonia in the year preceding asthma onset, representing

6440-405: The degree of shortness of breath. It may be subjectively rated on a scale from 1 to 10 with descriptors associated with the number (The Modified Borg Scale ). The MRC breathlessness scale suggests five grades of dyspnea based on the circumstances and severity in which it arises. A number of labs may be helpful in determining the cause of shortness of breath. D-dimer , while useful to rule out

6532-421: The development of asthma, but exposure at an older age may provoke bronchoconstriction. Evidence supporting the hygiene hypothesis includes lower rates of asthma on farms and in households with pets. Use of antibiotics in early life has been linked to the development of asthma. Also, delivery via caesarean section is associated with an increased risk (estimated at 20–80%) of asthma – this increased risk

6624-804: The duration of dyspnea are useful in knowing the etiology of dyspnea. Acute shortness of breath is usually connected with sudden physiological changes, such as laryngeal edema , bronchospasm , myocardial infarction , pulmonary embolism , or pneumothorax . Patients with COPD and idiopathic pulmonary fibrosis (IPF) have a mild onset and gradual progression of dyspnea on exertion, punctuated by acute exacerbations of shortness of breath. In contrast, most asthmatics do not have daily symptoms, but have intermittent episodes of dyspnea, cough, and chest tightness that are usually associated with specific triggers, such as an upper respiratory tract infection or exposure to allergens. Acute coronary syndrome frequently presents with retrosternal chest discomfort and difficulty catching

6716-546: The early morning. These episodes are usually associated with widespread but variable airflow obstruction within the lung that is often reversible either spontaneously or with treatment". There is currently no precise test for the diagnosis, which is typically based on the pattern of symptoms and response to therapy over time. Asthma may be suspected if there is a history of recurrent wheezing, coughing or difficulty breathing and these symptoms occur or worsen due to exercise, viral infections, allergens or air pollution. Spirometry

6808-455: The effectiveness of new medications. It may also be helpful in guiding treatment in those with acute exacerbations. Asthma is clinically classified according to the frequency of symptoms, forced expiratory volume in one second (FEV 1 ), and peak expiratory flow rate . Asthma may also be classified as atopic (extrinsic) or non-atopic (intrinsic), based on whether symptoms are precipitated by allergens (atopic) or not (non-atopic). While asthma

6900-674: The efficacy of inhaled corticosteroids, the mainstay of asthma control management. Shortness of breath Dyspnea is a normal symptom of heavy physical exertion but becomes pathological if it occurs in unexpected situations, when resting or during light exertion. In 85% of cases it is due to asthma , pneumonia , cardiac ischemia , COVID-19 , interstitial lung disease , congestive heart failure , chronic obstructive pulmonary disease , or psychogenic causes, such as panic disorder and anxiety (see Psychogenic disease and Psychogenic pain ) . The best treatment to relieve or even remove shortness of breath typically depends on

6992-624: The emergency room with shortness of breath. It is the most common lung disease in both developing and developed countries affecting about 5% of the population. Other symptoms include wheezing , tightness in the chest, and a non productive cough. Inhaled corticosteroids are the preferred treatment for children, however these drugs can reduce the growth rate. Acute symptoms are treated with short-acting bronchodilators. Pneumothorax presents typically with pleuritic chest pain of acute onset and shortness of breath not improved with oxygen. Physical findings may include absent breath sounds on one side of

7084-685: The experience of "breathlessness" (which may be either acute or chronic). While shortness of breath is generally caused by disorders of the cardiac or respiratory system , others such as the neurological , musculoskeletal , endocrine , hematologic , and psychiatric systems may be the cause. DiagnosisPro, an online medical expert system , listed 497 distinct causes in October 2010. The most common cardiovascular causes are myocardial infarction and heart failure while common pulmonary causes include chronic obstructive pulmonary disease , asthma , pneumothorax , pulmonary edema and pneumonia . On

7176-451: The home if a person has allergic symptoms to said pet. Dietary restrictions during pregnancy or when breastfeeding have not been found to be effective at preventing asthma in children and are not recommended. Omega-3 consumption, Mediterranean diet and antioxidants have been suggested by some studies to potentially help prevent crises but the evidence is still inconclusive. Reducing or eliminating compounds known to sensitive people from

7268-802: The level of respiration is inappropriate for the body's status then dyspnea might occur. There is also a psychological component to dyspnea, as some people may become aware of their breathing in such circumstances but not experience the typical distress of dyspnea. The initial approach to evaluation begins by assessment of the airway, breathing, and circulation followed by a medical history and physical examination . Signs and symptoms that represent significant severity include hypotension , hypoxemia , tracheal deviation , altered mental status, unstable dysrhythmia , stridor , intercostal indrawing, cyanosis , tripod positioning , pronounced use of accessory muscles ( sternocleidomastoid , scalenes ) and absent breath sounds. A number of scales may be used to quantify

7360-422: The number of lower respiratory infections . Other efforts that show promise include: limiting smoke exposure in utero , breastfeeding , and increased exposure to daycare or large families, but none are well supported enough to be recommended for this indication. Early pet exposure may be useful. Results from exposure to pets at other times are inconclusive and it is only recommended that pets be removed from

7452-404: The pattern of symptoms, response to therapy over time, and spirometry lung function testing. Asthma is classified according to the frequency of symptoms of forced expiratory volume in one second (FEV 1 ), and peak expiratory flow rate . It may also be classified as atopic or non-atopic, where atopy refers to a predisposition toward developing a type 1 hypersensitivity reaction. There

7544-525: The predicted best. Moderate is defined as between 80 and 200 L/min, or 25% and 50% of the predicted best, while severe is defined as ≤ 80 L/min, or ≤25% of the predicted best. Acute severe asthma , previously known as status asthmaticus, is an acute exacerbation of asthma that does not respond to standard treatments of bronchodilators and corticosteroids. Half of cases are due to infections with others caused by allergen, air pollution, or insufficient or inappropriate medication use. Brittle asthma

7636-504: The rates have increased significantly since the 1960s. Asthma was recognized as early as Ancient Egypt . The word asthma is from the Greek ἆσθμα , âsthma , which means 'panting'. Asthma is characterized by recurrent episodes of wheezing , shortness of breath , chest tightness , and coughing . Sputum may be produced from the lung by coughing but is often hard to bring up. During recovery from an asthma attack (exacerbation) ,

7728-653: The risk of asthma with both having increased in recent years. Several factors may be at play including decreased respiratory function due to a buildup of fat and the fact that adipose tissue leads to a pro-inflammatory state. Beta blocker medications such as propranolol can trigger asthma in those who are susceptible. Cardioselective beta-blockers , however, appear safe in those with mild or moderate disease. Other medications that can cause problems in asthmatics are angiotensin-converting enzyme inhibitors , aspirin , and NSAIDs . Use of acid-suppressing medication ( proton pump inhibitors and H2 blockers ) during pregnancy

7820-550: The risk of developing asthma when acquired as young children. Certain other infections, however, may decrease the risk. The hygiene hypothesis attempts to explain the increased rates of asthma worldwide as a direct and unintended result of reduced exposure, during childhood, to non-pathogenic bacteria and viruses. It has been proposed that the reduced exposure to bacteria and viruses is due, in part, to increased cleanliness and decreased family size in modern societies. Exposure to bacterial endotoxin in early childhood may prevent

7912-692: The sputum may appear pus-like due to high levels of white blood cells called eosinophils . Symptoms are usually worse at night and in the early morning or in response to exercise or cold air. Some people with asthma rarely experience symptoms, usually in response to triggers, whereas others may react frequently and readily and experience persistent symptoms. A number of other health conditions occur more frequently in people with asthma, including gastroesophageal reflux disease (GERD), rhinosinusitis , and obstructive sleep apnea . Psychological disorders are also more common, with anxiety disorders occurring in between 16 and 52% and mood disorders in 14–41%. It

8004-424: The term asthma because there is lack of clinical data on inflammation in airways. In adults, COPD , congestive heart failure , airway masses, as well as drug-induced coughing due to ACE inhibitors may cause similar symptoms. In both populations vocal cord dysfunction may present similarly. Chronic obstructive pulmonary disease can coexist with asthma and can occur as a complication of chronic asthma. After

8096-409: The underlying cause. Dyspnea, in medical terms, is "shortness of breath". The American Thoracic Society defines dyspnea as: A subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity. Other definitions describe it as "difficulty in breathing", "disordered or inadequate breathing", "uncomfortable awareness of breathing", and as

8188-528: The underlying disease. Fan therapy to the face has been shown to relieve shortness of breath in patients with a variety of advanced illnesses including cancer. The mechanism of action is thought to be stimulation of the trigeminal nerve. Systemic immediate release opioids are beneficial in emergently reducing the symptom severity of shortness of breath due to both cancer and non cancer causes; long-acting/sustained-release opioids are also used to prevent/continue treatment of dyspnea in palliative setting. There

8280-413: The use of accessory muscles of respiration ( sternocleidomastoid and scalene muscles of the neck), there may be a paradoxical pulse (a pulse that is weaker during inhalation and stronger during exhalation), and over-inflation of the chest. A blue colour of the skin and nails may occur from lack of oxygen. In a mild exacerbation the peak expiratory flow rate (PEFR) is ≥200 L/min, or ≥50% of

8372-583: The workplace may be effective. It is not clear if annual influenza vaccinations affect the risk of exacerbations. Immunization, however, is recommended by the World Health Organization. Smoking bans are effective in decreasing exacerbations of asthma. While there is no cure for asthma, symptoms can typically be improved. The most effective treatment for asthma is identifying triggers, such as cigarette smoke , pets or other allergens, and eliminating exposure to them. If trigger avoidance

8464-508: Was to recruit outstanding investigators from other fields in order to bring fresh perspectives and research advances other fields to the study of asthma. The AAF is guided by a scientific review board, which selects the research projects that are funded by the AAF. The board represents a broad range of scientific disciplines and is composed largely of scientists outside the field of asthma research. After 20 years of funding basic research in asthma,

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