bronchial hyperreactivity (BHR)

Bleach is widely used for household cleaning. Although it is recognized that occupational use of bleach may have adverse respiratory health effects, it is unknown whether common domestic use of bleach may be a risk factor for asthma. To assess whether the domestic use of bleach for home cleaning is associated with asthma and other respiratory outcomes. Questionnaire-based information on respiratory symptoms and cleaning habits and data from skin prick-tests, bronchial responsiveness challenge and white blood cells were analyzed in 607 women participating in the follow-up of the Epidemiological Study on the Genetics and Environment of Asthma (EGEA). Bleach use was evaluated in 3 categories (<1 day/week; 1-3 days/week; 4-7 days/week "frequent"). Overall, 37% of the women reported using bleach weekly. Women using bleach frequently (11%) were more likely to have current asthma as compared to non-users (adjusted Odds-Ratio (aOR) = 1.7; 95% Confidence Interval (95%CI) 1.0-3.0...

To review recent developments in the mechanisms of chronic cough. Although cough prevalence is similar across the world, there are significant regional differences in the diseases associated with cough. This may represent regional differences in diet, environmental exposure, and diagnostic assessment and labelling. Cough can be reliably measured using several validated questionnaires and objective tools that monitor cough frequency and cough reflex sensitivity. Cough with eosinophilic bronchitis responds to anti-inflammatory therapy with corticosteroids and montelukast. The absence of airway hyperresponsiveness may be because of the release of a bronchoprotective mediator, prostaglandin E2. Cough with neutrophilic bronchitis is associated with rhinitis and gastroesophageal reflux disease. Laryngeal hypersensitivity (LHS) is an important new concept that explains cough mechanisms, identifies potentially new pharmacotherapies that target neural pathways and also transient receptor channels, and demonstrates how behavioural therapies can be effective in refractory cough. The concept also explains symptoms in a variety of related syndromes such as vocal cord dysfunction. New insights into cough mechanisms that focus on LHS help explain cough symptoms and the place of effective therapies including speech pathology intervention and neuromodulators.

Asymptomatic increased bronchial responsiveness (BR) appears to be a major risk factor for later development of asthma, but risk factors for increased BR are not well established. The relationship of age, gender, house dust mite allergy, number of blood eosinophils, and FEV1 to the degree of nonspecific BR was studied in a population sample of 665 adolescents and young adults, aged 13 to 23 years. Case history, especially concerning smoking habits and respiratory symptoms, was obtained by interview and a self-administered questionnaire. Pulmonary function, number of blood eosinophils, BR to inhaled histamine, and skin test reactivity to house dust mites were measured with standard techniques. BR was analyzed as both a continuous variable (dose-response slope) and a categorical variable (cutoff: PC20 16 mg/ml). Increasing number of blood eosinophils, sensitivity to house dust mite, and former or current symptoms of asthma were associated with increasing levels of BR, independently of the level of FEV1. Adjustment for prechallenge FEV1 revealed a strong association between lower prechallenge FEV1 and increasing level of BR (p less than 0.0001), whereas the previously observed association between female gender and higher level of BR vanished. Repeating the analyses after exclusion of subjects with former or current asthma (n = 85) showed an unchanged relationship between house dust mite allergy and level of BR whether or not prechallenge FEV1 was included in the regression model, whereas gender only influenced the level of BR when no adjustment was made for prechallenge FEV1. On the contrary, the number of blood eosinophils was only significantly associated with BR after adjustment for baseline FEV1. Comparable findings were observed when patients with former or current symptoms of asthma and subjects with a prechallenge FEV1 less than 80% of predicted value (n = 46) were excluded from the analyses. This analysis suggests that adjustment for prechallenge level of FEV1 should be considered in studies concerned with risk factors for symptomatic and asymptomatic bronchial hyperresponsiveness.

The evidence of exercise-induced bronchoconstriction (EIB) without asthma (EIBw A) occurring in athletes led to speculate about different endotypes inducing respiratory symptoms within athletes. Classical postulated mechanisms for bronchial obstruction in this population include the osmotic and the thermal hypotheses. More recently, the presence of epithelial injury and inflammation in the airways of athletes was demonstrated. In addition, neuronal activation has been suggested as a potential modulator of bronchoconstriction. Investigation of these emerging mechanisms is of major importance as EIB is a significant problem for both recreational and competitive athletes and is the most common chronic condition among Olympic athletes, with obvious implications for their competing performance, health and quality of life. Hereby, we summarize the latest achievements in this area and identify the current gaps of knowledge so that future research heads toward better defining the etiologic factors and mechanisms involved in development of EIB in elite athletes as well as essential aspects to ultimately propose preventive and therapeutic measures.

Bronchial hyperreactivity has long been recognized as a hallmark of chronic asthma. Less is known about the prevalence and mechanisms of hyperreactivity in chronic obstructive pulmonary disease (COPD). Currently, it is unclear whether the role and mechanisms of hyperreactivity are similar in patients with asthma and COPD or whether the underlying pathophysiologic abnormalities are different for both diseases. The aim of this review is to present an overview of current knowledge of the mechanisms of bronchial hyperreactivity in asthma and COPD.

This is an updated overview of indications, contraindications, performance and interpretation of bronchial challenge tests. As speciality, the diagnostic step by step scheme comprises in addition to the clinical case history a detailed exposure (occupational) history, lung function testing, assessment of nonspecific bronchial hyperresponsiveness, allergological diagnostics (skin prick test, measurement of specific IgE antibodies), privation and reexposure test and as gold standard specific bronchial challenge tests. The last mentioned tests are of particular importance in the framework of a diagnostic backup with regard to specific therapeutic and preventive measures and insurance regulations (occupational disease?). Specific bronchial challenge tests and their variant, the workplace-related challenge test, serve to objectify or exclude the clinical relevance and the current state of a respiratory sensitization. They require a comprehensive experience of the physician performing the...