Capsaicin Cough Reflex Sensitivity Research Articles

Staphylococcus aureus enterotoxin sensitization is associated with declined capsaicin cough sensitivity in chronic obstructive pulmonary disease

Sensitization to Staphylococcus aureus (S. aureus) enterotoxins (SEs) A (SEA) and B (SEB) is associated with the pathogenesis of several chronic airway diseases, including asthma and chronic rhinosinusitis, but its role in chronic obstructive pulmonary disease (COPD) remains unclear. This cohort study aimed to investigate the impact of sensitization to SEs on total IgE levels, and capsaicin cough reflex sensitivity (C-CS) in COPD. This study prospectively enrolled 68 patients with COPD from the outpatient department at Nagoya City University Hospital and Shizuoka General Hospital, Japan, from June 2018 to January 2020 for posthoc analysis. Patient characteristics and biomarkers, including total IgE, and C-CS, were collected. We additionally measured and serum SEA-IgE and SEB-IgE levels for this analysis. Total IgE and SEs-IgE levels in individuals with COPD were compared to those of 20 healthy individuals. The correlation between C-CS and IgE levels was evaluated using Pearson’s correlation coefficient. Multivariate analyses were used to adjust the impact on SE sensitization in total IgE levels and C-CS. The prevalence of SEs sensitization was higher in patients with COPD (23.5%, N = 16) than in healthy individuals (0%, N = 0) at a cut-off value of 0.35 UA/mL or more (p = 0.018). There was a negative correlation between total serum SEB-IgE levels and declined C-CS values. Multivariate analysis showed that SEs sensitization was associated with increased total IgE levels, and declined C-CS values. This study indicated that SEs sensitization was associated with increased IgE levels and decreased C-CS in COPD. This study was approved by the ethics committee of Nagoya City University (60-18-0012) and registered in the UMIN Clinical Trials Registry (Registry ID UMIN000032497).

Cough desensitization treatment for patients with refractory chronic cough: results of a second pilot randomized control trial

ObjectiveThe purpose of this study was to collect pilot efficacy data on a novel treatment for refractory chronic cough (RCC), which we call cough desensitization treatment (CDT).Design and methodsIn this parallel cohort, sham-controlled, randomized controlled trial, 21 adults with RCC were randomly assigned to 12 sessions of either CDT (progressive doses of aerosolized capsaicin while behaviorally suppressing cough; n = 11) or a sham treatment (repeated exposure to aerosolized saline; n = 9). The Leicester Cough Questionnaire (LCQ) was the primary outcome measure. Perceived cough severity with a visual analogue scale and cough challenge testing (for measuring cough-reflex sensitivity) were secondary outcome measures. Data were analyzed with mixed effects linear regression and follow-up contrasts.ResultsResults on all measures favored CDT. Excluding one sham participant, whose baseline LCQ scores were deemed unreliable, mean change in LCQ at 3-weeks post treatment was 6.35 and 2.17 in the CDT and sham groups, respectively. There was moderate to strong evidence of a greater improvement in the CDT group in total LCQ score (p = .058) and LCQ Psychological domain (p = .026) and Physical domain (p = .045) scores. Strong evidence was found for a greater reduction in urge-to-cough during CCT in the CDT group (p = .037) and marginal for a reduction in the capsaicin cough-reflex sensitivity (p = .094). There was weak evidence of a greater reduction in cough severity in the CDT group (p = .103).DiscussionAlthough the study is limited due to the small sample size, the data provide additional evidence supporting further research on CDT. CDT resulted in a greater change in the primary efficacy measure (LCQ) than both pharmaceutical and behavioral treatments currently found in the literature.Trial RegistrationThis trial (NCT05226299) was registered on Clinicaltrials.gov on 07/02/2022.

Tiotropium for refractory cough in asthma via cough reflex sensitivity: A randomized, parallel, open-label trial

BackgroundWe previously reported in an uncontrolled study that tiotropium alleviated chronic cough in asthma refractory to inhaled corticosteroids and long-acting β2 agonists (ICS/LABA) by modulating capsaicin cough reflex sensitivity (C-CRS). ObjectiveWe sought to determine the antitussive effects of tiotropium for refractory cough in asthma in a randomized, parallel, open-label trial. MethodsA total of 58 patients with asthma having chronic cough refractory to ICS/LABA were randomized in a 2:1 ratio to add tiotropium 5 μg (39 patients) or theophylline 400 mg (19 patients) for 4 weeks. Patients underwent workups, including capsaicin cough challenge test and subjective measures such as cough severity visual analog scales (VAS). We adopted C5, the lowest capsaicin concentration to induce at least 5 coughs, as an index of C-CRS. We also performed a posthoc analysis to identify factors predicting tiotropium responders, who found an improvement of at least 15 mm in cough severity VAS. ResultsA total of 52 patients (tiotropium, 38; theophylline, 14) completed the study. Both tiotropium and theophylline significantly improved cough severity VAS and cough-specific quality of life. Tiotropium, but not theophylline, significantly increased C5, whereas pulmonary function did not change in either group. In addition, changes in cough severity VAS correlated with changes in C5 values in the tiotropium group. A posthoc analysis revealed that heightened C-CRS (C5 ≤1.22 µM) before the addition of tiotropium was an independent predictor for tiotropium responders. ConclusionTiotropium may alleviate chronic cough in asthma refractory to ICS/LABA by modulating C-CRS. Heightened C-CRS may predict responsiveness to tiotropium for refractory cough in asthma. Trial RegistrationClinical Trials Registry ID: UMIN000021064 (https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000024253).

Decreased capsaicin cough reflex sensitivity predicts hospitalisation due to COPD

IntroductionPatients with chronic obstructive pulmonary disease (COPD) are often hospitalised due to severe acute exacerbation (AE) or community-acquired pneumonia (CAP). Previous studies revealed the association of cough reflex sensitivity with...

Reflux-related symptoms reflect poor asthma control and the presence of airway neuronal dysfunction

BackgroundGastroesophageal reflux may be associated with the worsening of asthma by increasing cough reflex sensitivity. Hull Airway Reflux Questionnaire (HARQ) consists of 14 prevalent reflux-related symptoms. It may be useful in predicting the presence of cough reflex hypersensitivity in asthma. MethodsFrom August 2018 to July 2020, 266 asthmatic patients completed the HARQ. They underwent blood analysis, spirometry, fraction of exhaled nitric oxide (FeNO) measurement, and the capsaicin cough challenge test. Patients were considered to have reflux-related symptoms if their HARQ scores were 13 points or higher. We evaluated the association between reflux-related symptoms and clinical asthma outcomes. Finally, we performed a multivariate analysis to determine the clinical significance of the HARQ for asthma. This study was registered in the University Hospital Medical Information Network (UMIN000040732). ResultsThe mean HARQ scores were 13.1 (standard deviation 12.0). Patients in the high HARQ scores group (HARQ ≥13, n = 105) showed a lower prevalence of atopic predisposition, lower levels of FeNO, heightened capsaicin cough reflex sensitivity, poorer asthma control, and more frequent admissions due to asthma than those in the low HARQ groups (all p values < 0.05). The HARQ was useful in selecting patients with poor controlled asthma and those with severe cough when the cut-off value was set at 13. Multivariate analysis revealed that heightened capsaicin cough reflex sensitivity affected reflux-related symptoms, as well as lower levels of FeNO and younger age. ConclusionsHigher HARQ scores (≥13) may be useful in predicting not only poor asthma condition but also the presence of airway neuronal dysfunction in patients with asthma to some extent.

Characteristics of the European Thoracic Society/American Thoracic Society severe asthma definition as a determinant of future use of biologics/bronchial thermoplasty.

BackgroundInternational guidelines define severe uncontrolled asthma. Biologics or bronchial thermoplasty (Bio/BT) are recommended for such patients.ObjectivesTo determine which definitions of severe uncontrolled asthma are associated with an additional Bio/BT treatment in patients with severe uncontrolled asthma.MethodsConsecutive 107 asthmatics (including 15 patients for whom Bio/BT was introduced within 3 months after examination), classified as treatment step 4 according to the Global Initiative for Asthma 2015 guideline, were eligible for this analysis. Patients were assessed using the European Thoracic Society/American Thoracic Society (ERS/ATS) severe uncontrolled asthma guideline as defined by these 4 characteristics: poor control (ACT < 20), frequent exacerbations (≥2/yr), admissions (≥1/yr), and airflow limitation (forced expiratory volume in 1 second < 80% of predicted), along with comorbidities, and biomarkers, including blood granulocytes, fractional nitric oxide, and capsaicin cough reflex sensitivity (C-CS). These indices were compared between patients with and without Bio/BT introduction, and multivariate logistic regression analysis was performed to determine the association of the 4 definitions with treatment needs for Bio/BT.ResultsPatients who were introduced to Bio/BT had heightened C-CS, heavier smoking history, and a greater prevalence of diabetes mellitus than those without (p < 0.05). Poor asthma control (ACT < 20), frequent exacerbations (≥2/yr), and admissions (≥1/yr) were relevant to the future use of Bio/BT in the multivariate regression analysis. Type 2-related biomarkers including absolute eosinophil counts were higher in patients in the Bio introduction group than in the BT introduction group. Meanwhile, there was no significant difference of the 4 characteristics of severe uncontrolled asthma definition between patients in the Bio and those in the BT groups.ConclusionAlthough multiple factors such as treatment cost and asthma phenotypes affect treatment decision-making, the definition of poor asthma control, frequent exacerbations and admission by the ERS/ATS guidelines were important factors for an additional intensive treatment for severe uncontrolled asthma.Trial RegistrationUMIN Clinical Trials Registry: UMIN000024734

Increased Capsaicin Sensitivity in Patients With Severe Asthma Is Associated With Worse Clinical Outcome

Y Kanemitsu, K Fukumitsu, R Kurokawa. Am J Respir Crit Care Med . 2020;201(9):1068–1077 To study the role of capsaicin cough reflex sensitivity (C-CS) as a marker of airway neuronal dysfunction in severe asthmatics. The study included 157 adults with asthma based on symptoms, positive methacholine challenge, and treatment response to inhaled corticosteroids, of which 122 patients had severe asthma based on Global Initiative for Asthma (GINA) guidelines. Patients were enrolled between November 2016 and October 2019. Current smokers were excluded. This is an observational prospective cohort study. All enrolled participants completed the asthma control test (ACT), …

Tiotropium Attenuates Refractory Cough and Capsaicin Cough Reflex Sensitivity in Patients with Asthma

Asthmatic cough is often refractory to standard treatments such as inhaled corticosteroids (ICS) and long-acting β2 agonists (LABA). Tiotropium may modulate cough reflex sensitivity of acute viral cough, but its efficacy in asthmatic cough remains unknown. To evaluate whether tiotropium improves cough and cough reflex sensitivity in patients with asthma refractory to ICS/LABA. Seventeen consecutive patients with asthma with chronic cough despite the use of ICS/LABA (13 women; 43.4 ± 19.0 years; average ICS dose, 651 ± 189 μg/d; fluticasone equivalent) were additionally treated with tiotropium (5 μg/d) for 4 to 8 weeks to examine its effects on pulmonary function and capsaicin cough reflex sensitivity (cough thresholds C2 andC5). Cough severity, cough-specific quality of life, and asthma control were also evaluated using cough visual analog scales (VASs), the Japanese version of Leicester Cough Questionnaire (J-LCQ), and Asthma Control Test (ACT), respectively. Patients with an improved cough VAS score of 15 mm or more were considered responders to tiotropium. Tiotropium significantly improved cough VAS, J-LCQ, and ACT scores, but not FEV1. Changes in cough VAS score correlated with those in C2 (r=-0.58; P= .03), C5 (r=-0.58; P= .03), and ACT scores (r=-0.62; P= .02), but not in FEV1 in the overall patients. When analyses were confined to the 11 responders, tiotropium significantly improved capsaicin cough reflex sensitivity within the subgroup (C2: P= .01 and C5: P= .02) and versus the nonresponders (C2: P= .004 and C5: P= .02). Tiotropium may alleviate asthmatic cough refractory to ICS/LABA by modulating cough reflex sensitivity but not through bronchodilation.

The measurement of cough response to bronchoconstriction induced by methacholine inhalation in healthy subjects: An examination using the Astograph method

ABSTRACTBackground: We demonstrated that heightened cough response to bronchoconstriction is a fundamental feature of cough variant asthma (CVA). To evaluate this physiological feature of CVA in daily clinical practice, it is necessary to clarify the cough response to bronchoconstriction in healthy subjects. We evaluated cough response to methacholine (MCh)-induced bronchoconstriction in healthy subjects. A forced oscillometry technique was used to measure airway resistance changes with Mch. Methods: Healthy never-smokers (21 men, 20 women; mean 22.3 ± 3.7 years) participated. None had a >3-week cough history, clinically significant respiratory or cardiovascular disorders, or disorders that might put subjects at risk or influence the study results or the subjects’ ability to participate. Twofold increasing concentrations of Mch chloride diluted in phosphate-buffered saline (0.039 to 160 mg/mL) were inhaled from nebulizers at 1-minute intervals during subjects’ tidal breathing after the baseline respiratory resistance (Rrs) was recorded. Mch inhalation continued until Rrs reached twice the baseline value and forced expiratory volume in 1 second (FEV1) decreased to <90% of baseline value. Spirometry was measured before Mch inhalation and immediately after Rrs had increased twofold. Coughs were counted during and for 30 minutes after Mch inhalation. The cough reflex sensitivity to capsaicin was also examined. Results: The number of coughs was 11.1 ± 14.3 (median, 7.0; range, 0 to 71; reference range, 0 to 39.7). There was no significant difference in the cough response between the sexes. The reproducibility of the cough response to bronchoconstriction was sufficient. No correlation existed between the bronchoconstriction-induced cough response and capsaicin cough-reflex sensitivity. Conclusions: Using the Astograph method, cough response to bronchoconstriction could be measured easily, safely and highly reproducibly in healthy subjects.

Laryngeal sensory dysfunction in laryngeal hypersensitivity syndrome

Diseases associated with laryngeal dysfunction include chronic refractory cough (CRC), paradoxical vocal fold movement (PVFM), muscle tension dysphonia (MTD) and globus pharyngeus. We hypothesized the presence of a common sensory laryngeal dysfunction, the 'laryngeal hypersensitivity' syndrome, in these conditions. The aim of the study was to compare symptoms and sensory function in patients with CRC, PVFM, MTD and globus. The 103 participants included healthy controls (n = 13) and four case groups: CRC (n = 33), PVFM (n = 28), globus pharyngeus (n = 11) and MTD (n = 18). Participants completed self-report questionnaires: Symptom Frequency and Severity Scale, Voice Handicap Index and the Laryngeal Paraesthesia Questionnaire; and quantitative sensory testing: capsaicin cough reflex sensitivity, hypertonic saline challenge, the timed swallow test, acoustic voice testing, cough frequency monitor and a voice stress test. All case groups reported a high-symptom burden in comparison to controls. The case groups showed a similar pattern of symptoms, with impairment in each of the cough, respiration, vocal and upper airway symptom domains. Objective testing revealed significant sensory impairment in the case groups compared to controls and also showed an overlap in sensory dysfunction between the four case groups. Furthermore, there was cross-sensory stimulation of symptoms whereby stimulation of a particular response resulted in symptoms in another domain. These discrete clinical laryngeal syndromes display considerable overlap in their clinical features and a common sensory dysfunction, supporting the 'laryngeal hypersensitivity' hypothesis. Reconceptualizing functional laryngeal disorders as a form of laryngeal hypersensitivity syndrome provides an alternative approach to management of these perplexing conditions.

P150 The Development of a Cough Hypersensitivity Questionnaire (CHQ)

Introduction and objectivesCough reflex hypersensitivity (CRH) is a key feature of most patients with a refractory chronic cough and has distinct clinical features of hypertussia, allotussia (cough due to nontussive...

Cough Reflex Sensitivity Improves with Speech Language Pathology Management of Refractory Chronic Cough

Speech language pathology is an effective management intervention for chronic cough that persists despite medical treatment. The mechanism behind the improvement has not been determined but may include active cough suppression, reduced cough sensitivity or increased cough threshold from reduced laryngeal irritation. Objective measures such as cough reflex sensitivity and cough frequency could be used to determine whether the treatment response was due to reduced underlying cough sensitivity or to more deliberate control exerted by individual patients. The number of treatments required to effect a response was also assessed. The aim of this study was to investigate subjective and objective measures of cough before, during and after speech language pathology treatment for refractory chronic cough and the mechanism underlying the improvement. Adults with chronic cough (n = 17) were assessed before, during and after speech language pathology intervention for refractory chronic cough. The primary outcome measures were capsaicin cough reflex sensitivity, automated cough frequency detection and cough-related quality of life. Following treatment there was a significant improvement in cough related quality of life (Median (IQR) at baseline: 13.5 (6.3) vs. post treatment: 16.9 (4.9), p = 0.002), objective cough frequency (Mean ± SD at baseline: 72.5 ± 55.8 vs. post treatment: 25 ± 27.9 coughs/hr, p = 0.009), and cough reflex sensitivity (Mean ± SD log C5 at baseline: 0.88 ± 0.48 vs. post treatment: 1.65 ± 0.88, p < 0.0001). This is the first study to show that speech language pathology management is an effective intervention for refractory chronic cough and that the mechanism behind the improvement is due to reduced laryngeal irritation which results in decreased cough sensitivity, decreased urge to cough and an increased cough threshold. Speech language pathology may be a useful and sustained treatment for refractory chronic cough. Australian New Zealand Clinical Trials Register, ACTRN12608000284369.

Cough reflex sensitivity improves with speech language pathology management of refractory chronic cough

RationaleSpeech language pathology is an effective management intervention for chronic cough that persists despite medical treatment. The mechanism behind the improvement has not been determined but may include active cough suppression, reduced cough sensitivity or increased cough threshold from reduced laryngeal irritation. Objective measures such as cough reflex sensitivity and cough frequency could be used to determine whether the treatment response was due to reduced underlying cough sensitivity or to more deliberate control exerted by individual patients. The number of treatments required to effect a response was also assessed.ObjectiveThe aim of this study was to investigate subjective and objective measures of cough before, during and after speech language pathology treatment for refractory chronic cough and the mechanism underlying the improvement.MethodsAdults with chronic cough (n = 17) were assessed before, during and after speech language pathology intervention for refractory chronic cough. The primary outcome measures were capsaicin cough reflex sensitivity, automated cough frequency detection and cough-related quality of life.ResultsFollowing treatment there was a significant improvement in cough related quality of life (Median (IQR) at baseline: 13.5 (6.3) vs. post treatment: 16.9 (4.9), p = 0.002), objective cough frequency (Mean ± SD at baseline: 72.5 ± 55.8 vs. post treatment: 25 ± 27.9 coughs/hr, p = 0.009), and cough reflex sensitivity (Mean ± SD log C5 at baseline: 0.88 ± 0.48 vs. post treatment: 1.65 ± 0.88, p < 0.0001).ConclusionsThis is the first study to show that speech language pathology management is an effective intervention for refractory chronic cough and that the mechanism behind the improvement is due to reduced laryngeal irritation which results in decreased cough sensitivity, decreased urge to cough and an increased cough threshold. Speech language pathology may be a useful and sustained treatment for refractory chronic cough.Trial RegistrationAustralian New Zealand Clinical Trials Register, ACTRN12608000284369.

Effect of Pressure Stress Applied to the Airway on Cough-Reflex Sensitivity in Guinea Pigs

We hypothesized that cough stress of the airway wall results in a self-perpetuating cough-reflex cycle in which antigen-induced increase in cough-reflex sensitivity results in pathologic cough, and the cough in turn further amplifies cough-reflex sensitivity. To examine cough-reflex sensitivity in an experimental animal model. We developed an experimental guinea pig model in which airway collapse similar to that in cough was induced by rapid negative pressure applied to the airway of artificially ventilated animals. We examined the influence of this stimulus on cough-reflex sensitivity to inhaled capsaicin and bronchoalveolar lavage (BAL) cell components. After the termination of artificial ventilation, the number of coughs due to capsaicin was measured, and BAL was performed. Capsaicin cough-reflex sensitivity and the number of BAL neutrophils were increased 6 hours after stimulus application, decreasing to control levels by 24 hours. Cough-reflex sensitivity or BAL cell components were not changed in the absence of stimulus application. The number of BAL neutrophils correlated significantly with the number of coughs. Hydroxyurea inhibited the stimulus-induced increase in the number of coughs and airway neutrophil accumulation. Our findings suggest that cough itself is a traumatic mechanical stress to the airway wall that induces neutrophilic airway inflammation and cough-reflex hypersensitivity. Cough stress to the airway wall results in a self-perpetuating cough-reflex cycle.

Acidification of the oesophagus acutely increases the cough sensitivity in patients with gastro‐oesophageal reflux and chronic cough

Gastro-oesophageal reflux disease (GORD) is one of the most common causes of chronic cough; however, the mechanisms by which GOR initiates coughing are incompletely understood. We address the hypothesis that acidification of oesophagus acutely increases the cough reflex sensitivity in patients with GORD and chronic cough. Nine patients with GORD with chronic cough and 16 patients with GORD without cough were recruited. In a randomized double blind study, saline and acid (HCl, 0.1 mol L(-1)) were separately infused into oesophagus via naso-oesophageal catheter. Cough reflex sensitivity to inhaled capsaicin was determined immediately after completion of each infusion. Infusion of acid into oesophagus increased capsaicin cough reflex sensitivity in patients with GORD and chronic cough. In contrast, acid had no effect on the cough sensitivity in patients with GORD without cough. In a separate study, acid infusion into oesophagus did not affect the cough sensitivity in 18 healthy subjects. We conclude that acid in the oesophagus acutely increases the cough reflex sensitivity to capsaicin in patients with GORD and chronic cough. This phenomenon may contribute to the pathogenesis of cough due to GORD.

Cough and Glottic-Stop Reflex Sensitivity in Health and Disease

Little is known about the normal ranges and repeatability of cough reflex sensitivity measurements, or the relationship of cough reflex sensitivity to other upper airway reflexes in subjects with chronic dry cough. We set out to define the normal range of cough reflex sensitivity and its repeatability in health and disease, and to assess its relationship to the glottic-stop reflex. Prospective, cross-sectional study. We measured capsaicin cough reflex sensitivity in 134 healthy subjects and 88 patients with respiratory disease, and assessed the repeatability over 2 weeks in a subgroup of individuals (healthy subjects, 15; chronic cough patients, 15). In another subgroup (healthy patients, 16; chronic cough patients, 14), we measured the sensitivity of the glottic-stop reflex (using inhaled ammonia). Capsaicin cough sensitivity varied widely in the population of healthy subjects, and there was considerable overlap of cough reflex sensitivity between healthy control subjects and patients with cough. The intraclass correlation coefficients for repeatability of cough sensitivity (concentration of capsaicin that causes two coughs, and concentration of capsaicin that causes five coughs) were 0.89 and 0.88, respectively. Patients with chronic cough had a significantly more sensitive glottic-stop reflex than healthy subjects (glottic-stop sensitivity threshold, 483 ppm vs 1,029 ppm, respectively; p = 0.01), and there was a significant positive correlation between glottic-stop and cough reflex sensitivity (r = 0.5; p < 0.01). We have shown a wide variation of cough reflex sensitivity in healthy subjects, although the measurement does have good 2-week repeatability. There was a reasonably close relationship between cough sensitivity and glottic-stop reflex sensitivity, indicating either that the cough reflex and the glottic-stop reflex share a common pathway or that subjects who have a chronic cough have a global abnormality of upper airway reflexes.

Chronic tonsillar enlargement and cough: preliminary evidence of a novel and treatable cause of chronic cough.

Tonsillar enlargement is sometimes seen in patients with otherwise unexplained chronic cough although its significance is unclear. In this study, the authors set out to test the hypothesis that cough symptoms and cough reflex sensitivity will improve after tonsillectomy in patients with otherwise unexplained chronic cough and enlarged tonsils. Eight consecutive patients with unexplained chronic cough and enlarged tonsils were recruited from 236 patients seen in a cough clinic between 2000 and 2001. Six patients with enlarged tonsils and no cough who were undergoing tonsillectomy for other reasons were recruited as a control group. All patients rated cough severity on a cough visual analogue score (0-100 mm) and had capsaicin cough reflex sensitivity measurement twice before and again 3 months after tonsillectomy. Patients with a chronic cough had heightened cough reflex sensitivity compared with the control group at baseline. There was a significant improvement in mean cough visual analogue score 3 months after tonsillectomy in patients with chronic cough (mean difference 30 mm; 95% confidence interval of difference 8-51 mm). The geometric mean concentration of capsaicin required to cause five coughs increased from 4 to 207 micromol L(-1) after tonsillectomy in patients with chronic cough (mean difference from baseline 5.6 doubling concentrations; 95% confidence interval of difference 3.1-8.2). There was no change in cough reflex sensitivity in control patients after tonsillectomy. These preliminary findings suggest for the first time a possible role for tonsillectomy in patients with enlarged tonsils in whom other causes of cough have been ruled out.

Suction Apparatus for Ambulances

<b>Background:</b> There is increasing evidence of an association between organ specific autoimmune diseases, particularly autoimmune thyroid disease and respiratory morbidity. A study was undertaken to determine whether patients with autoimmune thyroid disease have objective evidence of airway inflammation and dysfunction. <b>Methods:</b> Twenty six non-smoking women with treated hypothyroidism and 19 non-smoking controls completed a symptom questionnaire and underwent full lung function tests, capsaicin cough reflex sensitivity measurement, methacholine challenge test, and sputum induction over two visits. <b>Results:</b> Symptoms of cough (p = 0.01), dyspnoea (p = 0.01), sputum production (p = 0.004), and wheeze (p = 0.04) were reported more commonly in patients than controls. Patients with hypothyroidism had heightened cough reflex sensitivity compared with controls (geometric mean concentration of capsaicin causing five coughs: 40 <i>v</i> 108 mmol/l; mean difference 1.4 doubling doses; 95% confidence interval of difference 0.4 to 2.5; p = 0.008) and a significantly higher proportion of patients had airway hyperresponsiveness (methacholine provocative concentration (PC₂₀) &lt;8 mg/ml: 38% <i>v</i> 0%; p = 0.016). Patients with hypothyroidism also had a significantly higher induced sputum total neutrophil cell count (p = 0.01), total lymphocyte count (p = 0.02), and sputum supernatant interleukin-8 concentrations (p = 0.048). <b>Conclusion:</b> Patients with treated hypothyroidism report more respiratory symptoms and have objective evidence of airway dysfunction and inflammation.