• A person with asthma may not feel symptoms all the time. (medlineplus.gov)
  • She had wheezing and allergy symptoms in childhood, and her mother and 1 cousin have confirmed asthma. (cmaj.ca)
  • The presence of certain key symptoms may suggest the presence of asthma, but can also result from airway inflammation alone, from chronic rather than reversible airflow limitation, or from other respiratory and nonrespiratory conditions. (cmaj.ca)
  • Moreover, asthma symptoms correlate poorly with abnormalities of lung function 9 and airway inflammation, 10 , 11 and thus in isolation may suggest a less severe form of the disease than is actually present. (cmaj.ca)
  • Asthma is an inflammatory disease 13 associated with symptoms resulting from abnormalities of airway function, in particular wide, short-term variations in airflow resistance in the intrapulmonary airways. (cmaj.ca)
  • The chronic inflammation of asthma is associated with airway hyperresponsiveness that leads to recurrent symptoms, yet lung function may nevertheless remain normal. (cmaj.ca)
  • Identification of airway hyperresponsiveness thus has clinical value, particularly in the diagnosis of asthma in people with normal spirometry results or with symptoms uncharacteristic of asthma. (cmaj.ca)
  • If symptoms occur two times a week, the asthma is persistent. (healthline.com)
  • We find that some patients with childhood asthma go into remission, but likely have residual lung changes, and manifest asthma symptoms when they get older," he added. (healthline.com)
  • Conclusion-Children with asthma reported by their parents in 1968 were more likely than not to be free of symptoms as adults. (bmj.com)
  • 2 3 Impaired lung function in childhood predicts asthmatic symptoms as a teenager, although this association might be confounded by undiagnosed asthma. (bmj.com)
  • First, many adults have had symptoms their whole life and are only diagnosed in older age. (sharecare.com)
  • Second, asthma symptoms are sometimes triggered after a specific health problem, such as viral pneumonia. (sharecare.com)
  • No one knows why, but some people seem to go through a 'honeymoon period' when they don't have symptoms, only to have asthma reappear later in life. (sharecare.com)
  • While symptoms in children and teens usually come and go, adults tend to have more persistent symptoms. (sharecare.com)
  • Having multiple illnesses at once can exacerbate asthma symptoms. (sharecare.com)
  • Asthma meds only treat symptoms-they do not cure the disease,' he says. (sharecare.com)
  • This would then suggest that some cases of asthma and some other lung deficiencies could be symptoms of a larger problem - the body reacting to a loss of one of its primary defense mechanisms in the lungs. (naturalnews.com)
  • A further study conducted in Ethiopia found that there was a direct, dose-associated association between acetaminophen use and allergic symptoms and asthma. (naturalnews.com)
  • Clinicians should be aware of the potential for cleaning products used in the home to cause respiratory symptoms and possibly asthma," wrote Kenneth D. Rosenman, M.D., professor at Michigan State University, in an editorial in the same issue of the journal. (health.am)
  • One of the problems is that doctors prescribe asthma medication based on symptoms such as wheezing, coughing or shortness of breath. (allergicliving.com)
  • These are common symptoms when the airways are restricted, and not exclusive to asthma. (allergicliving.com)
  • If diagnosed with asthma, but later experiencing no symptoms such as shortness of breath or coughing, he would ask for reassessment. (allergicliving.com)
  • Inhaled corticosteroids (ICS) and sodium cromoglycate (SCG) have been advocated as medications to control persistent asthma symptoms among children and adults, yet information on which class of drugs is superior has been conflicting. (cochrane.org)
  • Five respiratory endotypes have been identified using a cluster-based approach: NA1 (n=463) asymptomatic, NA2 (n=169) with respiratory symptoms, CA1 (n=50) with active treated adult-onset asthma, poor lung function, high blood neutrophil counts and high fluorescent oxidation products level, CA2 (n=203) with mild middle-age asthma, rhinitis and low immunoglobulin E level, and CA3 (n=114) with inactive/mild untreated allergic childhood-onset asthma. (bmj.com)
  • Data on asthma and asthma-related symptoms and selected home environmental factors were collected using a modified European Community Respiratory Health Survey II questionnaire. (neha.org)
  • The studied respondents recorded a prevalence rate of asthma and asthma-related symptoms in summer (7.5%) in Zunyi. (neha.org)
  • Among a variety of risk factors, asthma in childhood, kitchen in the living room or bedroom, mixed fuel stove, cooking oil fumes, secondhand smoke, mold growth, and home furnishings were associated with increased risks of asthma and asthma-related symptoms. (neha.org)
  • Adding a LABA also improved symptoms more than increasing the steroid dose, but at levels modest enough that asthma-related quality of life was unchanged. (thennt.com)
  • However, cough-specific studies in asthma are limited as this symptom is not included as a specific symptom of asthma control and is generally not captured independently of other symptoms in most studies of asthma. (guidelinecentral.com)
  • If response is incomplete in those with CVA or if cough is the remaining isolated symptom following treatment with inhaled corticosteroids in patients with asthma in whom cough was one of their symptoms we suggest stepping-up the inhaled corticosteroid dose and considering a therapeutic trial of a leukotriene inhibitor after reconsideration of alternative causes of cough. (guidelinecentral.com)
  • The evidence base supporting the step-wise treatment for asthma is very strong (as per the Global Initiative for Asthma, GINA), whereas cough-specific studies in asthma are limited as this symptom is not captured independently of other symptoms in most studies of asthma. (guidelinecentral.com)
  • Doctors rank asthma into four classifications according to their intensity and frequency of symptoms. (medicalnewstoday.com)
  • The symptoms of asthma can occur occasionally or persistently. (medicalnewstoday.com)
  • To diagnose asthma, a doctor will ask about people's family history and medical conditions to understand the symptoms and what causes them. (medicalnewstoday.com)
  • People with moderate persistent asthma exhibit symptoms daily, which can hinder their everyday activities. (medicalnewstoday.com)
  • As moderate persistent asthma occurs daily, exposure to allergens and irritants can trigger these symptoms. (medicalnewstoday.com)
  • People with asthma have symptoms when the airways tighten, inflame, or fill with mucus. (webmd.com)
  • Not every person with asthma has the same symptoms in the same way. (webmd.com)
  • Your symptoms may also vary from one asthma attack to the next, being mild during one and severe during another. (webmd.com)
  • Some people with asthma may go for long periods without having any symptoms. (webmd.com)
  • It is important to recognize and treat even mild asthma symptoms to help you prevent severe episodes and keep asthma under better control. (webmd.com)
  • An asthma attack can get worse quickly, so it's important to treat these symptoms right away. (webmd.com)
  • To classify your asthma severity, your doctor will consider how often you have signs and symptoms and how severe they are. (mayoclinic.org)
  • The right medications for you depend on a number of things - your age, symptoms, asthma triggers and what works best to keep your asthma under control. (mayoclinic.org)
  • In genetically susceptible individuals, these interactions can lead the patient with asthma to symptoms of breathlessness, wheezing, cough, and chest tightness. (medscape.com)
  • If I start to feel asthma symptoms when I run, I just take my reliever. (asthmafoundation.org.nz)
  • To determine the Frequence and severity of symptoms related to asthma, rhinitis and atopic eczema in young adults, using the standard self-applicable ISAAC written questionnaire (WQ). (bvsalud.org)
  • With the exception of asthma and its symptoms, there was predominance of these diseases in females. (bvsalud.org)
  • Depending on the person, asthma symptoms may become worse at night or with exercise. (wikipedia.org)
  • Asthma is classified according to the frequency of symptoms, forced expiratory volume in one second (FEV1), and peak expiratory flow rate. (wikipedia.org)
  • Long-acting beta agonists (LABA) or antileukotriene agents may be used in addition to inhaled corticosteroids if asthma symptoms remain uncontrolled. (wikipedia.org)
  • Some people with asthma rarely experience symptoms, usually in response to triggers, whereas others may react frequently and readily and experience persistent symptoms. (wikipedia.org)
  • Smoking during pregnancy and after delivery is associated with a greater risk of asthma-like symptoms. (wikipedia.org)
  • Consecutive adult patients aged 18 and above with chronic respiratory symptoms (lasting more than 8 weeks) and no evidence of active tuberculosis were recruited. (who.int)
  • C. pneumoniae has also been reported to worsen asthma severity [ 6 ] and be a cause of asthma exacerbation [ 7 ]. (ersjournals.com)
  • To assess the effectiveness of educational interventions administered following an acute exacerbation of asthma leading to presentation in the emergency department (ED). (cochrane.org)
  • 17 years) who had presented at an emergency department with an acute asthma exacerbation. (cochrane.org)
  • Adults with asthma who get pneumococcal pneumonia are at risk for additional complications including asthma exacerbation and invasive pneumococcal disease. (infectioncontroltoday.com)
  • RESULTS: Four hundred and thirteen adult asthmatic subjects who presented to their general practitioner with an acute exacerbation of asthma were recruited in 47 general practices in the United Kingdom. (bmj.com)
  • Documented history of at least 2 asthma exacerbation events within 12 months, and at least one of the exacerbations should occur during the treatment of medium-to-high dose ICS. (astrazenecaclinicaltrials.com)
  • 9) Participants must have a history of at least 1 asthma exacerbation event within 24 months prior to Visit 1. (astrazenecaclinicaltrials.com)
  • 4) Asthma exacerbation, requiring use of systemic corticosteroids or increase in the maintenance dose of OCS finalized within 30 days prior to Visit 1. (astrazenecaclinicaltrials.com)
  • During recovery from an asthma attack (exacerbation), it may appear pus-like due to high levels of white blood cells called eosinophils. (wikipedia.org)
  • The US Food and Drug Administration (FDA) recently approved three anti-interleukin (IL)-5 agents to treat eosinophilic asthma (reslizumab, benralizumab, and mepolizumab) as well as an anti-IL4Ra biologic agent (dupilumab) for the indication of moderate to severe asthma in patients 12 years and older. (medscape.com)
  • Clinical trial data suggest an improved clinical outcome for those older than 12 years with moderate to severe persistent asthma, with important endpoints an objective increased forced expiratory volume in 1 second (FEV1) and subjective decreased exacerbations of asthma, with an improved quality of life and reduced dependency on oral corticosteroids. (medscape.com)
  • Decreased IL-4, IL-5, and IL-13 signaling has had clinical endpoints such as decreased moderate to severe persistent asthma, decreased eczema, and a decreased incidence of chronic rhinosinusitis with nasal polyposis (this latter entity is seen with the use of dupilumab). (medscape.com)
  • About 10 percent of older patients are considered to have severe asthma and have a high risk of having exacerbations that result in emergency room visits or hospitalizations, he added. (healthline.com)
  • The subjects who had more severe asthma (especially if it developed after the age of 2 and was associated with reduced expiratory flow), were female, or had parents who had asthma were at an increased risk of having asthma as an adult. (bmj.com)
  • Most studies of the long term prognosis of childhood asthma have been based on selected groups of patients with severe or moderate asthma and provide limited information about the full range of the disease. (bmj.com)
  • Even if you've been managing asthma your whole life, there's a chance that the condition can become worse or more severe over time. (sharecare.com)
  • Treatment of severe asthma in adolescents and adults. (sharecare.com)
  • Severe Asthma. (sharecare.com)
  • Biologic Therapy for Severe Asthma. (sharecare.com)
  • Furthermore, the noneosinophilic phenotype of severe asthma is improved by macrolide antibiotics, a class of drugs that are active against C. pneumoniae [ 9 ]. (ersjournals.com)
  • This is a regional, multicentre, randomized, double-blind, placebo controlled, parallel group, phase 3 study designed to evaluate the efficacy and safety of 210 mg Q4W (SC) of tezepelumab in adults with severe, uncontrolled asthma on medium to high-dose ICS and at least one additional asthma controller medication with or without OCS. (astrazenecaclinicaltrials.com)
  • LABAs increase severe attacks and asthma deaths when used alone. (thennt.com)
  • The more severe the asthma, the more likely the benefit. (thennt.com)
  • Remarks: The evidence supporting a role for non-invasive measurement of airway inflammation in asthma, especially severe asthma (ATS/ERS Guideline), in predicting a beneficial response to corticosteroids is moderate. (guidelinecentral.com)
  • Doctors subdivide persistent asthma into mild, moderate, or severe. (medicalnewstoday.com)
  • Based on new data, GINA assesses asthma by mild, moderate, and severe and does not distinguish between intermittent and mild persistent asthma. (medicalnewstoday.com)
  • Benefits of omalizumab as add-on therapy in patient with severe persistent asthma who are inadequately controlled despite best available therapy (GINA 2002 step 4 treatment): INNOVATE. (medscape.com)
  • On the surface, managing equine asthma-which comprises both recurrent airway obstruction (RAO, or heaves, an often-severe chronic condition common in older horses) and inflammatory airway disease (IAD, a mild inflammatory disease often seen in younger equine athletes)-might not seem too complicated: Modify the horse's environment and treat, when needed, with corticosteroids and bronchodilators. (thehorse.com)
  • Severe asthma is a life-threatening disease, as Jake Cohn and Kailia Hill know all too well. (nationaljewish.org)
  • National Jewish Health is conducting research to save lives threatened by severe asthma. (nationaljewish.org)
  • I'm Jake Cohn and I've had severe asthma since birth. (nationaljewish.org)
  • My whole childhood just severe coughing spasms and asthma attacks have damaged my lungs. (nationaljewish.org)
  • Severe asthma can cause trouble talking or being active. (webmd.com)
  • Asthma, particularly severe asthma, is strongly associated with development of chronic obstructive pulmonary disease (COPD). (wikipedia.org)
  • Wechsler said physicians gauge the severity of a person's asthma and treat it accordingly. (healthline.com)
  • 5 Predictors of asthma in adulthood include various markers of initial severity,*RF 6-8* other atopic conditions, 4 7 8 and a family history of asthma. (bmj.com)
  • Subgroup analyses and meta-regression models were fit to explore heterogeneity of lung function outcomes by type of RCT, category of ICS or SCG dosage, asthma severity of participants, and study quality on outcomes. (cochrane.org)
  • Therefore, when treating patients with asthma, physicians should only prescribe Breo Ellipta for patients not adequately controlled on a long-term asthma control medication, such as an inhaled corticosteroid, or whose disease severity clearly warrants initiation of treatment with both an inhaled corticosteroid and a LABA. (gsk.com)
  • The Global Initiative for Asthma (GINA) guidelines divide asthma into three categories according to their severity. (medicalnewstoday.com)
  • Et al , Asthma severity , atopic status, allergen exposure and quality of life in the elderly persons. (medscape.com)
  • Determining your asthma severity helps your doctor choose the best treatment. (mayoclinic.org)
  • Asthma severity often changes over time, requiring treatment adjustments. (mayoclinic.org)
  • 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. (wikipedia.org)
  • Asthma-related hospitalizations were classified as those in which asthma was the first-listed discharge diagnosis. (cdc.gov)
  • Sara states that she has never received a diagnosis of asthma. (cmaj.ca)
  • The first step in managing asthma is to make the correct diagnosis. (cmaj.ca)
  • 8 However, despite the significant expenditure of health care resources on people with asthma, as well as decades of improvements in diagnosis and treatment and regular updates of evidence-based clinical practice guidelines, asthma control at the population level remains suboptimal. (cmaj.ca)
  • Canadian guidelines for the diagnosis and treatment of asthma have existed since 1989 and were most recently updated in 2003. (cmaj.ca)
  • In this series, we are using case-based examples to highlight recent changes in recommendations for asthma management and to highlight practical aspects of diagnosis and treatment. (cmaj.ca)
  • The case used here focuses on the diagnosis of asthma in adults. (cmaj.ca)
  • Although many clinicians diagnose asthma on the basis of a trial of therapy, objective measurements are necessary to confirm the clinical diagnosis. (cmaj.ca)
  • Thus, a conclusive diagnosis of asthma is based on tests designed to detect rapid changes in the forced expiratory volume in 1 second (FEV 1 ) or peak expiratory flow. (cmaj.ca)
  • Although this review focuses particularly on diagnosis, these tests can also be used to assess asthma control and as an aid in optimizing chronic therapy. (cmaj.ca)
  • Measurement of sputum eosinophilia has been proposed for clinical use in the diagnosis of asthma. (cmaj.ca)
  • Also, it's a combination of better diagnosis and the aging of younger people who have asthma. (healthline.com)
  • Dr. Sidney S. Braman, a pulmonologist who also published a recent study online about asthma in older adults, noted in his abstract that, "The older population has seen the greatest increase in the prevalence of current asthma in recent years… Unfortunately, geriatric-specific guidelines are not available for the diagnosis and treatment of asthma. (healthline.com)
  • An asthma diagnosis can happen at any age. (sharecare.com)
  • While many people with asthma are diagnosed as children, an asthma diagnosis can happen at any age-including adults over the age of 50. (sharecare.com)
  • For women who used acetaminophen heavily, their chances of having an asthma diagnosis was 63% higher than were women who did not use it at all. (naturalnews.com)
  • Although all said they had been diagnosed with asthma, a "current asthma" diagnosis was ruled out in 203 study participants - or 33 per cent of the group. (allergicliving.com)
  • The diagnosis of potentially fatal asthma in hospitalized adults. (nih.gov)
  • The diagnosis of PFA identifies a higher risk patient with asthma. (nih.gov)
  • Two thousand sixty-four patients aged 18 and older with a physician diagnosis of asthma. (unboundmedicine.com)
  • Learn more about what an asthma diagnosis means with our Asthma & allergies hub. (medicalnewstoday.com)
  • National Asthma Education and Prevention Program: Expert panel report III: Guidelines for the diagnosis and management of asthma. (medscape.com)
  • Many medical conditions may be confused with asthma at initial diagnosis. (cdc.gov)
  • Increasing age, exertional breathlessness, prior diagnosis of asthma, BMI, and clinically diagnosed COPD and asthma were independently associated with obstructed lung function. (who.int)
  • Self reported asthma or wheezy breathing in the previous 12 months (current asthma). (bmj.com)
  • Subjects were assessed for current asthma, current wheeze, physician-diagnosed asthma and allergy at follow-up, which took place an average of nine years after their first assessment. (health.am)
  • There are two reasons why patients don't have current asthma," says respirologist Dr. Shawn Aaron, who led the research . (allergicliving.com)
  • We assessed the association between current asthma and SHS exposure in vehicles among adult never-smokers in Indiana, Kentucky, Louisiana and Mississippi. (bmj.com)
  • Results Among 17 863 never-smoking adults, 7.4% reported having current asthma, whereas 12.3% reported past 7-day SHS exposure in vehicles. (bmj.com)
  • Following adjustment, adults exposed to SHS in a vehicle had a higher odds of having current asthma compared with unexposed adults (OR=2.01, 95% CI 1.18 to 3.40). (bmj.com)
  • Conclusions Never-smoking adults recently exposed to SHS in a vehicle had higher odds of having current asthma compared with unexposed adults. (bmj.com)
  • Current asthma rates are not the same across demographic groups. (lung.org)
  • This page describes current asthma rates, defined as those who have ever been diagnosed with asthma by a healthcare professional and report still having asthma, by the following demographics: sex and age, race/ethnicity, Hispanic subgroups, family income, health insurance coverage, and state. (lung.org)
  • Blacks and American Indian/Alaska Natives have the highest current asthma rates compared to other races and ethnicities. (lung.org)
  • Hispanics (6.4%) and Asians (4.0%) had lower current asthma prevalence rates than other racial and ethnic groups. (lung.org)
  • Puerto Ricans in the continental United States have the highest current asthma rate of any racial or ethnic group, at 14.0 percent over 2016 to 2018. (lung.org)
  • In 2018, current asthma rates were significantly higher (11.0%) among those with a family income below the poverty threshold as compared to above the poverty threshold. (lung.org)
  • In 2018, current asthma rates among adults ages 18 to 65 were highest for those on Medicaid and lowest for those with no medical insurance. (lung.org)
  • In 2018, current asthma rates among adults ranged from 7.4 percent in Texas to 12.3 percent in Maine and West Virginia. (lung.org)
  • Adults were defined as having current asthma if they answered "yes" to the following two questions: "Have you ever been told by a doctor or other health professional that you had asthma? (cdc.gov)
  • In 2010, among employed adults aged 18-64 years who currently had asthma, 6.7% had been told their current asthma was work-related. (cdc.gov)
  • No significant differences by sex for either work-related current asthma or skin conditions were observed. (cdc.gov)
  • The figure above shows the percentage of employed adults aged 18-64 years with current asthma, skin condition, or carpal tunnel syndrome, who were told their condition was work-related, by sex during 2010, according to the National Health Interview Survey. (cdc.gov)
  • Current asthma, but not former asthma, is associated with increased all-cause mortality, heart disease mortality, and chronic lower respiratory tract disease mortality. (wikipedia.org)
  • A case-control cohort study showed that older adults with asthma have a higher rate of allergic sensitization, decreased lung function, and significantly worse quality of life when compared to controls. (medscape.com)
  • 1 The onset of asthma is often preceded by allergic disease (eczema or hay fever) and a positive result of skin tests with allergens (atopy). (bmj.com)
  • Allergens and Allergic Asthma. (sharecare.com)
  • Allergic rhinitis: evidence for impact on asthma. (sharecare.com)
  • Saltoun CA. Update on efficacy of allergen immunotherapy for allergic rhinitis and asthma. (medscape.com)
  • Causes or triggers of asthma can be divided into allergic and nonallergic etiologies. (medscape.com)
  • Co-morbidities of asthma include sinusitis, nasal polyposis, gastro-esophageal reflux disease (GERD) and allergic rhinitis. (medscape.com)
  • Risk factors for asthma include a family history of allergic disease, the presence of allergen-specific immunoglobulin E (IgE), viral respiratory illnesses , exposure to aeroallergens , cigarette smoke, obesity , and lower socioeconomic status. (medscape.com)
  • The prevalence of asthma and allergic sensitization was 4 and 6 times lower in the Amish population, with higher median endotoxin levels in house dust. (medscape.com)
  • The analyzed data indicate the need for further studies in young adults and the use of markers for allergic and atopic diseases. (bvsalud.org)
  • Inhaled corticosteroids (ICS) and sodium cromoglycate (SCG) have become established as effective controller medications for children and adults with asthma, but their relative efficacy is not clear. (cochrane.org)
  • Do not use Breo Ellipta for patients whose asthma is adequately controlled on low- or medium-dose inhaled corticosteroids. (gsk.com)
  • BACKGROUND: Oral corticosteroids used in short courses for acute asthma are regarded as safe, although the frequent use of these drugs may result in patients suffering from systemic side effects. (bmj.com)
  • In adult and adolescent patients with chronic cough due to asthma as a unique symptom (cough variant asthma [CVA]) we suggest that inhaled corticosteroids should be considered as first line treatment. (guidelinecentral.com)
  • The adjusted HR was 1·44 (95% CI 1·31-1·58) for those with three or more prescribed courses of oral corticosteroids, 1·27 (1·09-1·48) for those with two prescribed courses, 1·04 (0·93-1·16) for those with one prescribed course, and 1·06 (0·97-1·17) for those without any course, compared with adults without asthma. (ed.ac.uk)
  • Interpretation: Adults with asthma who have required two or more courses of oral corticosteroids in the previous 2 years or a hospital admission for asthma before March 1, 2020, are at increased risk of both COVID-19 hospitalisation and ICU admission or death. (ed.ac.uk)
  • Adherence to adding inhaled corticosteroids to rescue therapy in a pragmatic trial with adults with asthma: A pilot study. (bvsalud.org)
  • Underuse of guideline -recommended inhaled corticosteroids (ICS) controller therapy is a risk factor for greater asthma burden. (bvsalud.org)
  • It also helps to prevent asthma and improve lung function. (healthline.com)
  • Yet another study, also published in the American Journal of RCCM found that acetaminophen, aspirin, and ibuprofen were all linked to an increased risk of asthma and COPD (chronic obstructive pulmonary disease) and a decrease in lung function. (naturalnews.com)
  • This study pooled randomized controlled trials that directly compared the effects of ICS to SCG on measures of lung function, asthma control, and health care use. (cochrane.org)
  • ICS were superior to SCG on measures of lung function and asthma control for both adults and children with chronic asthma. (cochrane.org)
  • In subgroup analyses involving lung function measures, paediatric and adult studies judged to be of high quality had results consistent with the overall results. (cochrane.org)
  • Lung function measures in children were higher in studies with medium BDP-equivalent steroid dosages than low BDP-equivalent dosages, while adult studies could not be compared by steroid dosage since they all incorporated similar dosages. (cochrane.org)
  • Priorities for additional research in this area include assessment of health-related quality of life, lung function assessment, exploration of the relationship between socio-economic status and asthma morbidity, and better description of the intervention assessed. (cochrane.org)
  • This study demonstrates the harmful effects of indoor air pollution from indoor environmental exposure on the lung function of adult residents in summer and emphasizes the need for public health efforts to decrease exposure to indoor environmental risk factors. (neha.org)
  • We investigated the association between sub-clinical inflammation in adults with spontaneous asthma remission and future asthma relapse and lung function decline. (monash.edu)
  • Participants with spontaneous asthma remission at ages 45 (n = 466) and 50 (n = 318) were re-evaluated at age 53, and associations between baseline inflammatory biomarkers and subsequent asthma relapse and lung function decline were assessed. (monash.edu)
  • In contrast, we found no evidence of association between EBC NOx and either asthma relapse or lung function decline. (monash.edu)
  • If your lung function improves with use of a bronchodilator, it's likely you have asthma. (mayoclinic.org)
  • Medical conditions such as rhinosinusitis , gastroesophageal reflux , and aspirin or nonsteroidal anti-inflammatory drug (NSAID) sensitivity may also trigger or exacerbate asthma. (medscape.com)
  • Nevertheless, respiratory infection presenting purulent sputum can exacerbate asthma in children previously diagnosed with asthma. (cdc.gov)
  • The increase in the prevalence of asthma in developed countries 1- 5 and the remarkable differences in asthma prevalence between countries suggests that environmental exposures are important in the development of this disease. (bmj.com)
  • To examine the association of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) with the prevalence of asthma by atopic status and sex using nationally representative data in the US. (sutterhealth.org)
  • [ 7 ] Using a cross-sectional design, the authors compared children living on farms to those in a reference group with respect to the prevalence of asthma and to the diversity of microbial exposure. (medscape.com)
  • The studies found that children who lived on farms had a lower prevalence of asthma and atopy and were exposed to a greater variety of environmental microorganisms than children in the reference group. (medscape.com)
  • Follow @CDCasthma on Twitter to learn more about helping people with asthma live healthier lives by gaining control over their asthma. (cdc.gov)
  • Asthma has been underdiagnosed in older people because some people with asthma were told they had COPD [chronic obstructive pulmonary disease]," he told Healthline. (healthline.com)
  • People with asthma also use a bronchodilator to expand bronchial air passages and to ease breathing. (healthline.com)
  • This has been another challenging year for people with asthma and their carers. (asthma.org.au)
  • People with asthma have sensitive airways that tend to overreact and narrow when they come into contact with even slight triggers. (webmd.com)
  • A number of other health conditions occur more frequently in people with asthma, including gastroesophageal reflux disease (GERD), rhinosinusitis, and obstructive sleep apnea. (wikipedia.org)
  • Cavities occur more often in people with asthma. (wikipedia.org)
  • Forster, Felix (2022): Longitudinal investigation of the course of asthma and allergies in young German adults. (uni-muenchen.de)
  • What should I do when I know I am going to be around something that triggers my asthma? (medlineplus.gov)
  • Discrepancy in mortality peaks across ages might relate to different triggers and mechanisms associated with exacerbations for different groups, and a better understanding of these trends could aid in the treatment and prevention of asthma-related hospitalizations and mortality, she said. (medpagetoday.com)
  • To characterize national trends in mortality and hospitalizations attributable to asthma among children and young adults (persons aged less than 25 years) during 1980-1993, CDC analyzed mortality data from its multiple cause-of-death files and hospitalization data from the National Hospital Discharge Survey. (cdc.gov)
  • This report summarizes the results of that analysis, which indicate that asthma-related mortality and hospitalization rates are increasing among persons aged less than 25 years. (cdc.gov)
  • Data were analyzed by race because of previously reported differences in race-specific rates of death and hospitalization attributed to asthma (2). (cdc.gov)
  • From 1980 to 1993, the annual hospitalization rate for asthma among persons aged 0-24 years increased 28% (from 16.8 to 21.4 per 10,000 population). (cdc.gov)
  • Although the rate of hospitalization for asthma was highest and increased the most among children aged less than 1 year (from 35.6 to 64.7 per 10,000 population) ( Figure 2 ), the rate in 1993 had decreased from that in 1992 (66.3 per 10,000 population). (cdc.gov)
  • Among persons aged 5-24 years, the rates of asthma hospitalization remained relatively constant during 1980-1993. (cdc.gov)
  • BOSTON -- Winter is the season with a higher incidence of asthma exacerbations requiring hospitalization across all regions of the U.S. and age groups of adults, researchers reported here. (medpagetoday.com)
  • In 2019 asthma affected approximately 262 million people and caused approximately 461,000 deaths. (wikipedia.org)
  • One man in his 60s ended up going to Wechsler's Cohen Family Asthma Institute at NJH after seeing two physicians who had incorrectly diagnosed him with COPD. (healthline.com)
  • This short course will enhance your knowledge and equip you with the clinical skills required to manage patients with common respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD). (sunderland.ac.uk)
  • You must be a qualified secondary care nurse (RNDip HE Adult Nursing or above) with an interest in respiratory conditions, namely asthma and chronic obstructive pulmonary disease (COPD). (sunderland.ac.uk)
  • This report contains the key findings and recommendations derived from an analysis of data collected for the adult asthma and chronic obstructive pulmonary disease (COPD) organisational audit component of the National Asthma and COPD Audit Programme (NACAP). (hqip.org.uk)
  • The audit collected information on the resourcing and organisation of services relevant to the care of adult patients with asthma and COPD that are admitted to hospital. (hqip.org.uk)
  • Title : Asthma, chronic obstructive pulmonary disease, and asthma-COPD overlap among US working adults Personal Author(s) : Syamlal, Girija;Dodd, Katelynn E.;Mazurek, Jacek M. (cdc.gov)
  • Asthma is the most common chronic illness in childhood and is characterized by variable airflow obstruction with airway hyperresponsiveness. (cdc.gov)
  • To determine which factors measured in childhood predict asthma in adult life. (bmj.com)
  • These findings have implications for the treatment and prognosis of childhood asthma, targeting preventive and educational strategies, and understanding the onset of asthma in adult life. (bmj.com)
  • Few population based and truly prospective cohort studies have been published of the natural course of asthma from childhood to adult life. (bmj.com)
  • Dr. Wasserman also noted that childhood asthma sometimes comes back as you get older. (sharecare.com)
  • Inflammatory phenotypes are recognised in stable adult asthma, but are less well established in childhood and acute asthma. (ersjournals.com)
  • The occurrence and relative frequency of these phenotypes in acute asthma and childhood asthma are not known. (ersjournals.com)
  • Milgrom H., Berger W., Nayak A. et al, Treatment of childhood asthma with Anti- Immunoglobulin E Antibody (Omalizumab), Pediatrics Vol. 108, No. 2, August 2001 pp.e36. (medscape.com)
  • Asthma often begins in childhood, and the rates have increased significantly since the 1960s. (wikipedia.org)
  • BACKGROUND: Exposure to environmental tobacco smoke (ETS) is a risk factor for childhood asthma. (who.int)
  • A nested case-control study was performed in 515 adults with physician diagnosed asthma and 515 matched controls using dietary data obtained from 7 day food diaries. (bmj.com)
  • The main outcome measures were physician diagnosed asthma and current symptomatic asthma (diagnosed asthma and self-reported wheeze within the previous 12 months). (bmj.com)
  • 2) Documented physician-diagnosed asthma for at least 12 months prior to Visit 1. (astrazenecaclinicaltrials.com)
  • C. pneumoniae detection may be higher in children or in acute exacerbations of asthma, where there is also heterogeneity of the inflammatory response. (ersjournals.com)
  • Comparison of short courses of oral prednisolone and fluticasone propionate in the treatment of adults with acute exacerbations of asthma in primary care. (bmj.com)
  • CONCLUSIONS: There is no evidence of a significant difference in efficacy between a reducing dose course of oral prednisolone and high dose inhaled fluticasone propionate in mild exacerbations of asthma which do not require admission to hospital. (bmj.com)
  • Asthma is intermittent or persistent," Wechsler said. (healthline.com)
  • Our results support recent consensus statements in the U.S. and elsewhere that favour the use of ICS over SCG for control of persistent asthma. (cochrane.org)
  • People with moderate persistent asthma may experience difficulty breathing and coughing every day. (medicalnewstoday.com)
  • Around 64.8% of American adults with asthma have a persistent form of this condition. (medicalnewstoday.com)
  • Healthcare professionals do not know the exact cause of moderate persistent asthma, and it may vary from person to person. (medicalnewstoday.com)
  • Four sites recruited 33 Hispanic or black adults with persistent asthma , randomized them approximately 31 to intervention or usual care, and followed them for 12 weeks. (bvsalud.org)
  • The Centers for Disease Control and Prevention (CDC) reports that nearly 7 percent of people age 65 and older have asthma. (healthline.com)
  • According to the Centers for Disease Control and Prevention, more than 25 million people in the United States have asthma. (sharecare.com)
  • Adults with asthma are at increased risk for pneumococcal disease, yet according to a new Centers for Disease Control and Prevention (CDC) study published today in the American Journal of Preventive Medicine , just 54 percent of adults with work-related asthma-asthma triggered by an exposure at work-have been vaccinated against the infection. (infectioncontroltoday.com)
  • Some of the independent risk factors for asthma in older adults include house dust mite sensitization and maternal smoking. (medscape.com)
  • Researchers say doctors need to watch more carefully for asthma in seniors, and older adults need to adopt healthier lifestyles to avoid developing the ailment. (healthline.com)
  • These are some of the findings in a recent study on the effects of asthma on older adults conducted at National Jewish Health (NJH) in Colorado. (healthline.com)
  • Not everyone agrees that the incidence of asthma in older adults is rising. (healthline.com)
  • Asthma is also underdiagnosed and undertreated in older adults, Mathur said, because there can be many causes for shortness of breath, including heart disease. (healthline.com)
  • There are two reasons older adults get diagnosed with asthma for the first time, says Stephen Wasserman, MD. Wasserman is a professor of medicine in the division of Rheumatology, Allergy & Immunology at UCSD. (sharecare.com)
  • NA occurs typically in older adults and there is evidence that C. pneumoniae infection might precede the onset of adult asthma, as well as persisting in stable chronic asthmatics [ 8 ]. (ersjournals.com)
  • Electronic health record-based assessment of oral corticosteroid use in a population of primary care patients with asthma: an observational study. (sutterhealth.org)
  • Once asthma control is achieved and maintained, assess the patient at regular intervals and step down therapy (e.g., discontinue Breo Ellipta) if possible without loss of asthma control and maintain the patient on a long-term asthma control medication, such as an inhaled corticosteroid. (gsk.com)
  • It has become common practice for patients to increase their own inhaled corticosteroid intake when their asthma goes out of control, but it has never been established whether a high dose of inhaled corticosteroid can be as effective as a short course of oral corticosteroid in the treatment of acute exacerbations. (bmj.com)
  • Practice patterns for oral corticosteroid burst therapy in the outpatient management of acute asthma exacerbations. (medscape.com)
  • A Cox proportional hazard model was used to derive adjusted hazard ratios (HRs) and 95% CIs for the association between asthma and COVID-19 hospital admission and ICU admission or death, stratified by markers of history of an asthma attack defined by either oral corticosteroid prescription (prednisolone, prednisone, and dexamethasone) in the 2 years before March 1, 2020, or hospitalisation for asthma before March 1, 2020. (ed.ac.uk)
  • Adults were defined as having a skin condition if they answered "yes" to the following question: "During the past 12 months, have you had dermatitis, eczema, or any other red, inflamed skin rash? (cdc.gov)
  • Among the secondary outcomes was the rate of asthma exacerbations through 24 weeks. (nih.gov)
  • Women had higher AUCs (0.59-0.64) than men (0.50-0.58) across anthropometric indices and asthma outcomes. (sutterhealth.org)
  • The impact of educational intervention in this context on longer term outcomes relating to asthma morbidity is unclear. (cochrane.org)
  • The lack of statistically significant differences between asthma education and control groups in terms of peak flow, quality of life, study withdrawal and days lost were hard to interpret given the low number of studies contributing to these outcomes and statistical variation between the study results. (cochrane.org)
  • There were no asthma deaths in either group and just two life-threatening attacks, making it impossible to assess any differences in these outcomes. (thennt.com)
  • Background: The extent to which biomarkers of asthma activity persist in spontaneous asthma remission and whether such markers are associated with future respiratory outcomes remained unclear. (monash.edu)
  • Incidence and outcomes of asthma in the elderly: a population-based study in Rochester, Minnesota. (medscape.com)
  • We were asked by the UK's Joint Commission on Vaccination and Immunisation to undertake an urgent analysis to identify which adults with asthma were at an increased risk of serious COVID-19 outcomes to inform deliberations on booster COVID-19 vaccines. (ed.ac.uk)
  • 1 Asthma is episodic, and, although remission may occur during teenage years, it is uncommon after the age of 30. (bmj.com)
  • Others had it, but they are now in remission and their asthma is inactive. (allergicliving.com)
  • Asthma is complex - it's difficult to diagnose and some patients have periods of remission. (allergicliving.com)
  • BHR and high TNF-α during spontaneous remission were associated with an increased risk of asthma relapse. (monash.edu)
  • Conclusion: BHR and serum inflammatory cytokines have prognostic value in adults with spontaneous asthma remission. (monash.edu)
  • She and her group examined data from the National Inpatient Sample, consisting of patients age 18 years or older who had been admitted to the hospital for asthma (defined as the first three diagnoses using ICD-9-CM codes). (medpagetoday.com)
  • We performed record linkage between questionnaire-defined asthma and BMI, and hospital discharge diagnoses of type 2 diabetes in 34,782 Danish twins, 20-71 years of age. (ku.dk)
  • Chronic bronchitis (49.1%) and asthma (36.1%) were the most common clinical diagnoses. (who.int)
  • These include eosinophilic, neutrophilic, mixed granulocytic and paucigranulocytic asthma, defined by the presence and/or absence of airway eosinophilis and neutrophils. (ersjournals.com)
  • Asthma and non-asthmatic eosinophilic bronchitis (NAEB) are among the commonest causes of chronic cough in adults. (guidelinecentral.com)
  • The design of the study was not intended to determine the biological mechanism behind the increase in asthma with exposure to cleaning sprays, but Dr. Zock and colleagues propose a number of hypotheses, including the possibility that asthma is partially irritant-induced, that sprays contain sensitizers that are specific to asthma, and/or that an inflammatory response is involved in asthma development. (health.am)
  • The relative risk rates of developing adult asthma in relation to exposure to cleaning products could account for as much as 15 percent, or one in seven of adult asthma cases," wrote Dr. Zock. (health.am)
  • Prevalence of self-reported asthma and past 7-day SHS exposure in vehicles was calculated by demographics, voluntary smoke-free vehicle rules and SHS exposure in homes, public places and workplaces. (bmj.com)
  • Logistic regression was used to assess the adjusted association between asthma and SHS exposure in vehicles. (bmj.com)
  • Occupational exposure to irritants during the current or last held job was assessed by the updated occupational asthma-specific job-exposure matrix (levels of exposure: no/medium/high). (bmj.com)
  • Methods Data came from the 2011 Behavioral Risk Factor Surveillance System, a state-based telephone survey of US adults aged ≥18 years. (bmj.com)
  • Methods We used cross-sectional data from 999 adults (mean 45 years old, 46% men) from the case-control and familial Epidemiological study on the Genetics and Environments of Asthma (EGEA) study. (bmj.com)
  • Methods: This national incident cohort study was done in all adults in Scotland aged 18 years and older who were included in the linked dataset of Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II). (ed.ac.uk)
  • See the "Methods" Section of the documentation found at http://www.cdc.gov/asthma/NHIS/default.htm for information regarding standard errors. (cdc.gov)
  • Findings: Between March 1, 2020, and July 27, 2021, 561 279 (12·7%) of 4 421 663 adults in Scotland had clinician-diagnosed-and-recorded-asthma. (ed.ac.uk)
  • The results were consistent among children and adults. (cochrane.org)
  • To compare the relative effectiveness and adverse effects of ICS and SCG among children and adults with chronic asthma. (cochrane.org)
  • Randomized controlled trials comparing the effect of ICS with SCG in children and adults with chronic asthma. (cochrane.org)
  • Although, many cases of recurrent cough and wheezing in children and adults are due to asthma, other conditions are often misdiagnosed as asthma. (cdc.gov)
  • Association of general and central obesity and atopic and nonatopic asthma in US adults. (sutterhealth.org)
  • Using US national data, this study adds to the emerging evidence suggesting two possible distinct phenotypes: (1) obese men and women with atopic asthma and (2) obese women with nonatopic asthma. (sutterhealth.org)
  • When stratified by atopy, the association between primary education and uncontrolled asthma was seen in non-atopic (OR 3.42, 95% CI 1.30-8.96) but not in atopic subjects. (tuni.fi)
  • 0.0001) compared to the rest of the year, reported Pragya Shrestha, MD, of Reading Health System in Pennsylvania, in a presentation at the American College of Allergy, Asthma & Immunology annual meeting here. (medpagetoday.com)
  • American Academy of Allergy, Asthma & Immunology. (sharecare.com)
  • It's estimated that 8 per cent of Americans, or around 25 million people, had asthma in 2009, according to the American Academy of Allergy, Asthma & Immunology. (allergicliving.com)
  • The new standard of care in asthma is to immunologically phenotype the patient, assess the total immunoglobulin (Ig) E level, and obtain a complete blood cell (CBC) count with differential to ascertain the absolute eosinophil count. (medscape.com)
  • One potential cause of the variability in response to treatment is heterogeneity in the role of interleukin-13 expression in the clinical asthma phenotype. (nih.gov)
  • Paucigranulocytic asthma was the most common phenotype in both adults and children with stable asthma. (ersjournals.com)
  • once hospitalized, the death rate attributable to asthma for patients older than 65 years is 14 times higher than that of patients aged 18-35 years. (medscape.com)
  • GlaxoSmithKline plc (LSE: GSK) and Theravance, Inc. (NASDAQ: THRX) today announced that the US Food and Drug Administration (FDA) has approved BREO ® ELLIPTA ® (fluticasone furoate/vilanterol [FF/VI]) for the once-daily treatment of asthma in patients aged 18 years and older. (gsk.com)
  • Following submission of a supplemental new drug application (sNDA) to the FDA, Breo Ellipta has been approved for the once-daily treatment of asthma in patients aged 18 years and older. (gsk.com)
  • An sNDA for Breo Ellipta in asthma was submitted to the FDA in June 2014 and in April 2015 it was approved for the once-daily treatment of asthma in patients aged 18 years and older. (gsk.com)
  • We conducted a randomized, double-blind, placebo-controlled study of lebrikizumab, a monoclonal antibody to interleukin-13, in 219 adults who had asthma that was inadequately controlled despite inhaled glucocorticoid therapy. (nih.gov)
  • Although asthma has an equal incidence across all age groups, asthma in the elderly is often underdiagnosed and undertreated. (medscape.com)
  • Asthma is a chronic inflammatory disease characterized by hyperresponsiveness of airways to various stimuli. (medscape.com)
  • Asthma is a problem with the lung airways. (medlineplus.gov)
  • But when an asthma attack happens, it becomes hard for air to pass through your airways. (medlineplus.gov)
  • Asthma is a chronic lung disease that inflames and narrows the airways. (gsk.com)
  • Asthma is a chronic condition that affects the airways of the lungs, causing them to narrow and produce excessive mucus. (medicalnewstoday.com)
  • An asthma attack is the episode in which bands of muscle around the airways are triggered to tighten. (webmd.com)
  • When your airways are inflamed - a sign of asthma - you may have higher than normal nitric oxide levels. (mayoclinic.org)
  • Asthma is a long-term inflammatory disease of the airways of the lungs. (wikipedia.org)
  • Asthma Asthma is a condition in which the airways narrow-usually reversibly-in response to certain stimuli. (msdmanuals.com)
  • Available data from controlled clinical trials suggest that LABA increase the risk of asthma-related hospitalisation in paediatric and adolescent patients. (gsk.com)
  • Nearly 10,000 adults ages 18-64 years with asthma from 29 states who have ever held a job, representing an estimated 12 million people, were included in the analysis. (infectioncontroltoday.com)
  • This study examined the prevalence of inflammatory phenotypes and the presence of current C. pneumoniae infection in adults and children with stable and acute asthma. (ersjournals.com)
  • Asthma is a chronic inflammatory airway disease characterised by episodic exacerbations. (ersjournals.com)
  • There is heterogeneity in the airway inflammatory response in asthma that can be related to both exposures, such as allergen and infection, and to treatment [ 1 ]. (ersjournals.com)
  • We have previously categorised stable adult asthma into four inflammatory phenotypes based on induced sputum inflammatory cell counts [ 2 ]. (ersjournals.com)
  • Thus, C. pneumoniae may play a potential role in modulating the different inflammatory phenotypes of asthma, and NA in particular. (ersjournals.com)
  • 6) Participants must have received OCS for the treatment of asthma for at least 6 months prior to Visit 1 and on a stable dose of between ≥7.5 to ≤ 30 mg (prednisone or prednisolone) daily or daily equivalent for at least 1 month prior to Visit 1. (astrazenecaclinicaltrials.com)
  • The grade thus reflects the very strong evidence for step-wise treatment of asthma in general rather than specifically for cough. (guidelinecentral.com)
  • Adults with stable (n=29) or acute (n=22) asthma, healthy adults (n=11), children with stable (n=49) or acute (n=28) asthma, and healthy children (n=9) underwent clinical assessment and sputum induction. (ersjournals.com)
  • Also, other clinical factors play great roles in HRQoL in adult patients of asthma. (rutgers.edu)
  • There is also a group of patients that develops the onset of asthma when they are older. (healthline.com)
  • Also, people with adult-onset asthma usually don't 'outgrow' it, the way some children do. (sharecare.com)
  • The same journal (AJRCCM) published another study that linked acetaminophen with adult-onset asthma. (naturalnews.com)
  • Objective: Education in itself and as a proxy for socioeconomic status, may influence asthma control, but remains poorly studied in adult-onset asthma. (tuni.fi)
  • Our aim was to study the association between the level of education and asthma control in adult-onset asthma. (tuni.fi)
  • Conclusions: In high-income Nordic countries, lower educational level was a risk factor for uncontrolled asthma in subjects with adult-onset asthma. (tuni.fi)
  • Educational level should be considered in the management of adult-onset asthma. (tuni.fi)
  • 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. (wikipedia.org)
  • Most medications can work together without a problem-for example, most people are able to use inhaled medications for asthma even if they have other health concerns. (sharecare.com)
  • 5) Additional maintenance asthma controller medications are allowed. (astrazenecaclinicaltrials.com)
  • This classification is for individuals who are not currently taking any long-term medications to control their asthma. (medicalnewstoday.com)
  • Long-term asthma control medications, generally taken daily, are the cornerstone of asthma treatment. (mayoclinic.org)
  • Genetic differences may alter susceptibility to asthma, as well as responsiveness to asthma medications. (medscape.com)
  • The risk of asthma was increased in subjects with type 2 diabetes relative to nondiabetic subjects both in men (13.5%vs 7.5%), P = 0.001 and in women (16.6%vs 9.6%), P = 0.001. (ku.dk)
  • Most people think of asthma as a young person's disease, so they don't think of shortness of breath as asthma. (healthline.com)
  • Asthma is characterized by recurrent episodes of wheezing, shortness of breath, chest tightness, and coughing. (wikipedia.org)
  • Some people refer to asthma as " bronchial asthma . (webmd.com)
  • Asthma causes red, swollen bronchial tubes in your lungs. (webmd.com)
  • Public surveys illustrating patterns of ital status), chronic health problems (in- tobacco use and laying emphasis on factors cluding hypertension, diabetes, bronchial influencing smoking behaviour have been asthma, ischaemic heart disease and rheu- identified as areas of research priority for matic heart disease) and level of physical developing countries and an important activity. (who.int)
  • In addition, ICS were associated with fewer exacerbations (WMD -1.18 exacerbations per year, 95% CI -2.15 to - 0.21), lower asthma symptom scores, and less rescue bronchodilator use than SCG. (cochrane.org)
  • Without immediate treatment, such as with your asthma inhaler or bronchodilator , it will become harder to breathe. (webmd.com)
  • We present findings from a follow up over 25 years of random samples from a population survey of 7 year old Tasmanian schoolchildren, designed to assess the natural course of asthma. (bmj.com)
  • A study was undertaken to assess the independent associations of these nutrients with asthma in adults. (bmj.com)
  • NIH publication no. 08-4051) www.nhlbi.nih.gov/guidelines/asthma/asthgdln.htm (Accessed on July 12,2012). (medscape.com)
  • Aim The biological mechanisms of work-related asthma induced by irritants remain unclear. (bmj.com)