Increased resistance of the peripheral airways in patients with unexplained chronic cough.

Introduction Troublesome coughing that persists for more than 8 weeks without evident aetiology or effective therapy is termed unexplained chronic cough (UCC). Using impulse oscillometry (IOS) and spirometry, we assessed the functionalities of the large and small airways, respectively, in patients with UCC and in healthy control subjects. Methods On a single occasion, 50 patients with UCC (mean age, 61 years; 82% women) and 23 subjectively healthy controls (mean age, 58.

Validity and reliability of the Swedish version of the Leicester Cough Questionnaire in unexplained chronic cough.

Background: Cough is considered chronic when it lasts for >8 weeks. When no medical explanation can be found it is often called unexplained chronic cough (UCC), which may affect health-related quality of life (HRQOL). This study aimed to assesses the validity and reliability of the Swedish version of the Leicester Cough Questionnaire (LCQ-S) in patients with UCC.

Small and large airways' reactions to inhaled capsaicin in patients with chronic idiopathic cough, or asthma and in healthy control subjects.

Cough is a common medical problem, and when it persists for more than 8 weeks it is arbitrarily defined as chronic. While spirometry assesses the large airways, impulse oscillometry system (IOS) measures peripheral airway function. The present study investigated whether provocation with inhaled capsaicin affects the large and small airways in patients with chronic idiopathic cough (CIC) or asthma and in healthy controls.

Small and large airway reactions to osmotic stimuli in asthma and chronic idiopathic cough.

Background: Chronic cough is a common symptom and related to several pulmonary, airway and heart diseases. When all likely medical explanations for the coughing are excluded, there remains a large group of patients with chronic coughing, which is mostly a cough reflex easily triggered by environmental irritants and noxious stimuli. The main aim of this study was to improve the diagnostic ability to differentiate chronic idiopathic cough (CIC) from asthma.

Reliability and Validity of the Swedish Version of the Hull Airway Reflux Questionnaire (HARQ-S).

Introduction: Cough is a common symptom for which patients seek medical care and is defined as chronic if it has lasted for more than 8 weeks. The Hull Airway Reflux Questionnaire (HARQ) was developed with the aim of eliciting the major component of chronic cough. It comprises 14 items with a maximum total score of 70.

Long-Term Follow-Up in Patients With Airway Chemical Intolerance.

Objective: A 5-year follow-up study showed that a group of patients with airway symptoms from chemicals and scents had lasting symptoms, together with enduring increased capsaicin cough sensitivity. The aim was to follow up the same patients after another 5 years.

Methods: All previously participants were invited for an additional follow-up.

Physical Therapy Treatment of Impaired Chest Mobility in Patients with Airway Sensory Hyperreactivity.

Background And Purpose: In sensory hyperreactivity (SHR), patients have symptoms from the airways and the chest induced by environmental irritants like scenting products and cigarette smoke. They are characterized by increased cough reaction to inhaled capsaicin compared with healthy controls. Lung function tests are normal, and asthma medications have no or little effect.

Cough reduction using capsaicin.

Unlabelled: Chronic unexplained cough triggered by environmental irritants is characterized by increased cough reflex sensitivity, which can be demonstrated by means of inhaled capsaicin. Topical capsaicin can be used to improve non-allergic rhinitis and intestinal hypersensitivity and to reduce neuropathic pain.

Objectives: We established whether an oral intake of natural capsaicin (chilli) could desensitize the cough reflex and improve unexplained coughing.

Capsaicin cough threshold test in diagnostics.

Background: Among patients with chronic unexplained cough, there is a recognized subgroup with respiratory symptoms induced by environmental irritants like chemicals and odours. The diagnosis of sensory hyperreactivity (SHR) has been suggested for this group of patients and can be made using a tidal breathing capsaicin inhalation test. The aim of the present study was to evaluate the ability of a single-breath, dose-response capsaicin threshold test to discriminate such patients from control subjects.

A study of two generic health-related quality of life questionnaires--Nottingham Health Profile and Short-Form 36 Health Survey--and of coping in patients with sensory hyperreactivity.

Background: Sensory hyperreactivity (SHR) is one explanation for airway symptoms induced by chemicals and scents. Little is known about health-related quality of life (HRQOL) and coping, in this group of patients. A study was done in patients with SHR to (1) compare the Nottingham Health Profile (NHP) and the Short-Form 36 Health Survey (SF-36) in regard to their suitability, validity, reliability, and acceptability; (2) evaluate how the patients cope with the illness; (3) assess whether there are differences between women and men with respect to HRQOL and coping; and (4) assess whether there are differences between patients and normative data with respect to HRQOL and coping.

Capsaicin sensitivity in patients with chronic cough- results from a cross-sectional study.

Background: A subgroup of patients with chronic cough is recognised as having airway symptoms resulting exposure to chemicals and scents related to enhanced cough sensitivity to inhaled capsaicin. Sensory hyperreactivity, which has an estimated prevalence of more than 6%, is one possible explanation for the symptoms experienced by these patients. We hypothesized that a number of patients diagnosed with chronic unexplained cough also have coughing provoked by chemical irritants associated with augmented capsaicin cough reaction, but the extent of such a relation is not known.

Inhalation of menthol reduces capsaicin cough sensitivity and influences inspiratory flows in chronic cough.

Introduction: Chronic cough is a common clinical problem and there is a shortage of effective treatments for it. Within the group of transient receptor potential ion channels a receptor for the cooling substance menthol has been identified. This study aimed to assess whether pre-inhalation of dissolved, nebulised menthol could increase capsaicin cough thresholds and influence spirometric values.

Respiratory movement and pain thresholds in airway environmental sensitivity, asthma and COPD.

Introduction: Patients with "sensory hyperreactivity" (SHR) have airway environmental sensitivity, chronic cough and dyspnoea. Cough, chest discomfort and sense of difficulties getting air are some of the symptoms these patients seek medical attendance for. The patients have increased cough sensitivity to inhaled capsaicin, mediated by ion channel receptors on sensory nerves also known to react to pain stimuli.

Sensitivity to environmental irritants and quality of life in COPD.

It is a common clinical experience that patients with chronic obstructive pulmonary disease (COPD) complain of airway symptoms provoked by environmental irritants like chemicals and scents, although few studies can confirm such connections. The aim was to study the prevalence of airway symptoms induced by chemicals and scents in a group of patients with newly diagnosed CPOD and to analyze any relation to illness severity and quality of life. Eighty-one patients with COPD were recruited to the study.

Symptoms induced by environmental irritants and health-related quality of life in patients with chronic cough - A cross-sectional study.

Background: Chronic cough is a common condition, but some patients have no evident medical explanation for their symptoms. A group of patients has been identified, characterized by upper and lower airway symptoms triggered by chemicals and scents, and heightened cough sensitivity to inhaled capsaicin. Chronic cough is usually a prominent symptom in these patients, and it has been suggested that they suffer from sensory hyperreactivity.

Sensitivity to environmental irritants and capsaicin cough reaction in patients with a positive methacholine provocation test before and after treatment with inhaled corticosteroids.

Background: Increasing evidence points to a potential role for members of the transient receptor potential family of cation channels on several features of asthmatic disease. The cough sensitivity to inhaled capsaicin is known to reflect the reactivity of these airway sensory nerves.

Objective: The aim was to study, among patients having a positive methacholine provocation and diagnosed with asthma, capsaicin cough sensitivity, sensitivity to methacholine, and levels of exhaled nitric oxide before and after treatment with inhaled steroids, and further, to measure the self-reported impact from environmental irritants.

Down-regulation of cough sensitivity after eucapnic dry air provocation in chronic idiopathic cough.

Down-regulation of cough sensitivity in humans is rarely discussed in terms other than pharmacological treatment of cough or hypersensitive cough reflex. Chronic cough and increased cough sensitivity could be due to a number of airway and other diseases. When such conditions are excluded, there still remains a group of patients with no evident medical explanation for persistent coughing; such patients are often described as having "chronic idiopathic cough".

Dyspnea from exercise in cold air is not always asthma.

In the absence of other explanations, exercise-induced dyspnea is often labeled as a manifestation of asthma. The aim of this study was to use exercise provocation in cold air among patients with exercise-induced dyspnea, but without any bronchoconstriction, in order to study induced symptoms and different physiological parameters and to measure the possible influence of exercise in cold air on capsaicin cough sensitivity. Eleven patients with exercise-induced dyspnea but no asthma, along with 11 healthy controls, performed a capsaicin inhalation provocation on two occasions.

Capsaicin provocation using two different inhalation devices.

Background: Sensory hyperreactivity (SHR) has been suggested as one explanation for chemically induced airway symptoms; it can be diagnosed with a capsaicin inhalation test. Previous capsaicin inhalation studies of SHR have used a Pari Boy device. This model of inhalator device has become outdated, hence it is necessary to abandon it in favour of a new device.

Inhaled ethanol potentiates the cough response to capsaicin in patients with airway sensory hyperreactivity.

A suggested explanation for airway symptoms induced by chemicals and scents is sensory hyperreactivity (SHR) of airway mucosal nerves. Patients with SHR have increased cough sensitivity to inhaled capsaicin, mediated by transient receptor potential (TRP) ion channels. In animal experiments, some TRP receptors are potentiated by ethanol, which is why in this study, the aim was to evaluate whether a pre-inhalation of ethanol could influence the capsaicin cough response in patients with SHR.

Quality of life and capsaicin sensitivity in patients with airway symptoms induced by chemicals and scents: a longitudinal study.

Objective: It is common in asthma and allergy clinics to see patients presenting with upper and lower airway symptoms that are induced by chemicals and scents and not explained by allergic or asthmatic reactions. Previous studies have shown that these patients often have increased cough sensitivity to inhaled capsaicin; such sensitivity is known to reflect the airway sensory reactivity. The aim of this study was to evaluate the duration of symptoms induced by chemicals and scents and to measure health-related quality of life (HRQL) in patients with chemically induced airway symptoms.

Changes in levels of nerve growth factor in nasal secretions after capsaicin inhalation in patients with airway symptoms from scents and chemicals.

Patients complaining of upper and lower airway symptoms caused by scents and chemicals have previously been shown to have increased cough sensitivity to inhaled capsaicin, but the precise mechanisms behind this reaction are unknown. Hypothesizing that a neurochemical alteration related to sensory hyperreactivity (SHR) of the airway mucosa occurs, we measured levels of nerve growth factor (NGF) in nasal lavage fluid (NAL) before and after capsaicin inhalation provocations and related the capsaicin cough sensitivity to the NGF levels. Thirteen patients with SHR and 14 control subjects were provoked with capsaicin inhalation at three different doses.

Inhalation method determines outcome of capsaicin inhalation in patients with chronic cough due to sensory hyperreactivity.

Background: For patients with idiopathic chronic cough, a subgroup is recognised with respiratory symptoms induced by scents and chemicals. The diagnosis of sensory hyperreactivity (SHR) has been suggested for this group of patients and can be made using a capsaicin inhalation test. The aim of the present study was to compare the results of inhaling capsaicin by tidal breathing with those obtained by the dosimeter method regarding repeatability, agreement, and ability to distinguish patients with SHR from healthy controls.

Increased capsaicin cough sensitivity in patients with multiple chemical sensitivity.

Multiple chemical sensitivity (MCS) is characterized by chemically induced symptoms from multiple organ systems. No consistent physical findings or laboratory abnormalities have been determined for the associated symptoms. Twelve patients with chemically induced airway symptoms, who satisfied Cullen's criteria for MCS, were provoked double-blind, randomized with saline and three increments of inhaled capsaicin.

Capsaicin cough sensitivity in allergic asthmatic patients increases during the birch pollen season.

Background: A change in neural responsiveness may occur as the result of allergic inflammation in the lower airways as well as in the upper airways. In the lower airways, capsaicin cough sensitivity is known to reflect sensory neural reactivity.

Objective: The aim of this study was to establish whether allergic inflammation changes airway neural sensory reactivity during prolonged allergen exposure.