Andrew Simpson

Self-reported Symptoms after Induced and Inhibited Bronchoconstriction in Athletes

ABSTRACT Purpose A change in the perception of respiratory symptoms after treatment with inhaled beta2 agonists is often used to aid diagnosis of exercise-induced bronchoconstriction (EIB). Our aim was to test the association between subjective ratings of respiratory symptoms and changes in airway caliber after induced and inhibited bronchoconstriction in athletes with EIB. Methods Eighty-five athletes with diagnosed or suspected EIB performed a eucapnic voluntary hyperpnea (EVH) challenge with dry air. Of the 45 athletes with hyperpnea-induced bronchoconstriction [i.e., post-EVH fall in forced expiratory volume in 1 s (FEV1) ≥10%, EVH−], 36 were randomized in a double-blind, placebo-controlled, crossover study. Terbutaline (0.5 mg) or placebo was administered by inhalation 15 min before EVH. Spirometry (for FEV1) was performed before and after EVH, and respiratory symptoms were recorded 15 min after EVH on visual analog scales. Results Terbutaline inhibited bronchoconstriction (i.e., maximal fall in FEV1 <10% after EVH) in 83% of the EVH-positive athletes, with an average degree of bronchoprotection of 53% (95% confidence interval [CI], 45% to 62%). Terbutaline reduced group mean symptom scores (P < 0.01), but the degree of bronchoprotection did not correlate with individual differences in symptom scores between terbutaline and placebo. Of the 29 athletes who had less than 10% FEV1 fall after EVH in the terbutaline condition, almost half (48%) rated at least one respiratory symptom higher under terbutaline, and more than one quarter (28%) had a higher total symptom score under terbutaline. Conclusion Self-reports of respiratory symptoms in conditions of induced and inhibited bronchoconstriction do not correlate with changes in airway caliber in athletes with EIB. Therefore, subjective ratings of respiratory symptoms after treatment with inhaled beta2 agonists should not be used as the sole diagnostic tool for EIB in athletes.

Perspectives of patients and healthcare professionals on mHealth for asthma self-management

Mobile healthcare (mHealth) has the potential to revolutionise the self-management of long-term medical conditions such as asthma. A user-centred design is integral if mHealth is to be embraced by patients and healthcare professionals. The aim of this study was to determine the perspectives of individuals with asthma and healthcare professionals on the use of mHealth for asthma self-management. We used a sequential exploratory mixed methods design; focus groups informed the development of questionnaires, which were disseminated to individuals with asthma and healthcare professionals. Focus group participants (18 asthma patients and five healthcare professionals) identified 12 potential uses of mHealth. Questionnaire results showed that individuals with asthma (n=186) most frequently requested an mHealth system to monitor asthma over time (72%) and to collect data to present to healthcare teams (70%). In contrast, healthcare professionals (n=63) most frequently selected a system alerting patients to deteriorating asthma control (86%) and advising them when to seek medical attention (87%). Individuals with asthma were less likely than healthcare professionals (p<0.001) to believe that assessing medication adherence and inhaler technique could improve asthma control. Our data provide strong support for mHealth for asthma self-management, but highlight fundamental differences between the perspectives of patients and healthcare professionals. People with asthma and healthcare professionals strongly support the utility of mHealth for asthma self-management http://ow.ly/wyJC3096f4e

MyAirCoach: the use of home-monitoring and mHealth systems to predict deterioration in asthma control and the occurrence of asthma exacerbations; study protocol of an observational study.

Introduction Asthma is a variable lung condition whereby patients experience periods of controlled and uncontrolled asthma symptoms. Patients who experience prolonged periods of uncontrolled asthma have a higher incidence of exacerbations and increased morbidity and mortality rates. The ability to determine and to predict levels of asthma control and the occurrence of exacerbations is crucial in asthma management. Therefore, we aimed to determine to what extent physiological, behavioural and environmental data, obtained by mobile healthcare (mHealth) and home-monitoring sensors, as well as patient characteristics, can be used to predict episodes of uncontrolled asthma and the onset of asthma exacerbations. Methods and analysis In an 1-year observational study, patients will be provided with mHealth and home-monitoring systems to record daily measurements for the first-month (phase I) and weekly measurements during a follow-up period of 11 months (phase II). Our study population consists of 150 patients, aged ≥18 years, with a clinicians diagnosis of asthma, currently on controller medication, with uncontrolled asthma and/or minimally one exacerbation in the past 12 months. They will be enrolled over three participating centres, including Leiden, London and Manchester. Our main outcomes are the association between physiological, behavioural and environmental data and (1) the loss of asthma control and (2) the occurrence of asthma exacerbations. Ethics This study was approved by the Medical Ethics Committee of the Leiden University Medical Center in the Netherlands and by the NHS ethics service in the UK. Trial registration number NCT02774772.

A standard, single dose of inhaled terbutaline attenuates hyperpnea-induced bronchoconstriction and mast cell activation in athletes.

This study provides the first in vivo evidence for a mast cell stabilizing effect of the short-acting inhaled β2-adrenoceptor agonist terbutaline, when administered prophylactically at a clinically recommended dose (0.5 mg) before bronchial provocation with dry air. Our data therefore support the proposal that β2-adrenoceptor agonist-mediated mast cell stabilization is a major contributor to bronchoprotection in individuals with exercise-induced bronchoconstriction.

Effect of terbutaline on hyperpnoea-induced bronchoconstriction and urinary club cell protein 16 in athletes

Repeated injury of the airway epithelium caused by hyperpnoea of poorly conditioned air has been proposed as a key factor in the pathogenesis of exercise-induced bronchoconstriction (EIB) in athletes. In animals, the short-acting β2-agonist terbutaline has been shown to reduce dry airflow-induced bronchoconstriction and the associated shedding of airway epithelial cells. Our aim was to test the efficacy of inhaled terbutaline in attenuating hyperpnoea-induced bronchoconstriction and airway epithelial injury in athletes. Twenty-seven athletes with EIB participated in a randomized, double-blind, placebo-controlled, crossover study. Athletes completed an 8-min eucapnic voluntary hyperpnoea (EVH) test with dry air on two separate days 15 min after inhaling 0.5 mg terbutaline or a matching placebo. Forced expiratory volume in 1 s (FEV1) and urinary concentration of the club cell (Clara cell) protein 16 (CC16, a marker of airway epithelial perturbation) were measured before and up to 60 min after EVH. The maximum fall in FEV1 of 17 ± 8% (SD) on placebo was reduced to 8 ± 5% following terbutaline (P < 0.001). Terbutaline gave bronchoprotection (i.e., post-EVH FEV1 fall <10%) to 22 (81%) athletes. EVH caused an increase in urinary excretion of CC16 in both conditions (P < 0.001), and terbutaline significantly reduced this rise (pre- to postchallenge CC16 increase 416 ± 495 pg/μmol creatinine after placebo vs. 315 ± 523 pg/μmol creatinine after terbutaline, P = 0.016). These results suggest that the inhalation of a single therapeutic dose of terbutaline offers significant protection against hyperpnoea-induced bronchoconstriction and attenuates acute airway epithelial perturbation in athletes.

Levels of soya aeroallergens during dockside unloading as measured by personal and static sampling

Abstract Soya is an important worldwide agricultural product widely shipped and imported in bulk. It contains a number of recognised allergens and the use of soya products and its dockside unloading have been associated with occupational asthma and community episodes of asthma. Two recognised inhalation soya allergens, soya trypsin inhibitor (STI) and hydrophobic soya protein (HSP), were measured in personal and static air samples collected at a United Kingdom (UK) dock during 3 days of unloading three bulks of processed soya beans and soya pelletised husk. Static samples included task-related and those taken at the workplace perimeter and neighbouring sites. Soluble total protein (STP) and gravimetric dust analyses were also undertaken. While gravimetric dust results in personal air samples were below half of the current UK exposure limit of 10 mg m-3 for grain dust, and generally less than 0.5 mg m-3 for the static samples, airborne concentrations for STI and HSP ranged between 0-3,071 and 11-12,629 ng m-3, respectively, while the correlation between the two specific allergen measurements was generally good (Rank Spearman coefficient 0.74). The data from this investigation suggest that HSP is a more sensitive indicator of soya exposure than STI, but only for soya husk, while STI may be equipotent in detecting exposure to both hull and bean derived soya products. Both assays appear sensitive techniques for investigating the control of exposure to allergenic soy material. The endotoxin level in the husk bulk was 15-60-fold that found in the two chipped bean bulks. Soja je gotovo u cijelome svijetu važan poljoprivredni proizvod, pa se prevozi često i u velikim količinama. Sadrži mnoštvo poznatih alergena, a korištenje proizvoda od soje i rukovanje njima prilikom iskrcavanja robe povezivani su s pojavama profesionalne astme. Razine dvaju inhalacijskih alergena, soja tripsin inhibitora (STI) i hidrofobnog proteina sojina zrna (HSP), mjerene su u uzorcima zraka prikupljenim osobnim uzorkovačem i stacionarnim uzorkovačima u jednom britanskom lučkom doku tijekom 3 dana iskrcavanja triju pošiljaka prerađena sojina zrna i kuglica sojine mahune. Također je provedena analiza ukupnih topivih proteina i gravimetrijska analiza prašine. Rezultati gravimetrijske analize uzoraka prikupljenih osobnim uzorkovačem bili su dobrano ispod polovice trenutačne granice izloženosti u Velikoj Britaniji (10 mg m-3 za prašinu sjemena) i općenito ispod 0,5 mg m-3 kod statičnih uzoraka, a razine STI-a i HSP-a u zraku prikupljenom stacionarnim uzorkovačem bile su unutar raspona 0-3.071, odnosno 11-12.629 ng m-3. Korelacija između ta dva alergena bila je dobra (Rank Spearmanov koeficijent 0,74). Rezultati ovoga istraživanja pokazali su da je HSP precizniji pokazatelj izloženosti soji od STI-a, no samo za sojine mahune; STI bi mogao biti precizniji pokazatelj u pogledu proizvoda od sojine ljuske ili zrna. Obje su se vrijednosti pokazale preciznim tehnikama za praćenje izloženosti sojinim alergenima. Razina endotoksina u pošiljci sojinih mahuna bila je 15 do 60 puta veća od one u dvjema pošiljkama usitnjenog zrna.

Exercise-induced dehydration alters pulmonary function but does not modify airway responsiveness to dry air in athletes with mild asthma

This study is the first to investigate the effect of whole body dehydration on airway responsiveness. Our data suggest that the airway response to dry air hyperpnea in athletes with mild asthma and/or exercise-induced bronchoconstriction is not exacerbated in a state of mild dehydration. On the basis of recorded alterations in lung volumes, however, exercise-induced dehydration appears to compromise small airway function.