Exercise Challenge Test Research Articles

Bronchial Reactivity in Students from Moisture and Mold-Damaged Schools: Changes in Relation to Changes in Exposure

There is epidemiological and preliminary clinical evidence that exposure to moisture and mold growth is associated with wheezing and asthma in children. Lung function and challenge tests may find obstructive changes in the airways before clinically evident symptoms. The aim of the study was to evaluate lung function and bronchial reactivity in school children in a follow-up setting, and relate them to changes in mold exposure over a 3-year observation period. We performed flow-volume spirometry and an exercise challenge test by outdoor free running 3 years apart to the same 139 students from moisture-problem and control schools. The subjects were classified into four exposure groups: exposure continued, eased, started, and no exposure. There were no significant differences in spirometry or in the exercise challenge test among the children in the four different exposure groups. However, there was a trend that, on average, bronchial reactivity increased when exposure started, and decreased when exposure eased. Spirometry and exercise challenge offer no benefits over symptoms in the follow-up of symptomatic children exposed to moisture and/or molds.

Facial Cooling Causes Greater Exercise-Induced Bronchoconstriction in Children with Asthma

0462 PURPOSE: Exercising in cold air enhances bronchial response (BR) as compared to exercising in warm air. This may be due to intrathoracic cooling or to increased vagal activity caused by facial cooling. The purpose of this study was to determine the respective contribution to BR of direct (inhalation) and indirect (facial cooling) influences when children exercise in cold air, as well as the combined effect of both. METHODS: 14 children (8 girls, 6 boys) with asthma performed four exercise challenge tests in a climatic chamber, under one of the following conditions: 1) inhaling “warm” air while the face was exposed to “warm” air (WW, 21°C, 25% relative humidity (RH)), 2) inhaling warm air while the face was exposed to cold air (WC, 0°C, 80% RH,), 3) inhaling cold air while the face was exposed to cold air (CC), 4) inhaling cold air while the face was exposed to warm air (CW). The study was analyzed, using a 2-way ANOVA. RESULTS: Forced expiratory volume in the first second (FEV1) and maximal mid-expiratory flow (MMEF) values showed significant reductions during the entire trial, but the extent of reduction differed among the four experimental conditions. There was a significant condition × time interaction for FEV1 (p = 0.001), but not for MMEF (p = 0.10). FEV1 was significantly lower for CC, as compared to WC and CW at 5 and 10 minutes post-exercise. CONCLUSIONS: The combined challenges of inhaling cold air and facial cooling cause the greatest EIB in children with asthma, as compared to either of the isolated cold challenges; the contribution of small airways to flow limitation after exercising in cold air remains unclear. We suggest that vagal mechanisms play an additional role to bronchial cooling in exercise and cold-induced bronchoconstriction.

Facial cooling enhances exercise-induced bronchoconstriction in asthmatic children.

Exercising in cold air enhances bronchial responsiveness (BR) as compared with exercising in warm air. This may be due to intrathoracic cooling or to increased vagal activity caused by facial cooling. The purpose of this study was to compare the effects on BR of cold air inhalation and of facial exposure to cold air, as well as the combined effect of both. Fourteen children with asthma (eight girls) performed four exercise challenge tests in a climatic chamber, under one of the following conditions: 1) inhaling warm air while the face was exposed to warm air (WW, 21 degrees C, 25% relative humidity (RH)); 2) inhaling warm air while the face was exposed to cold air (WC, 0 degrees C, 80% RH); 3) inhaling cold air while the face was exposed to cold air (CC); and 4) inhaling cold air while the face was exposed to warm air (CW). The study was analyzed, using a one- and two-way ANOVA. Postexercise forced expiratory volume in the first second (FEV1) and maximal mid-expiratory flow (MMEF) values as percent predicted (% pred) showed significant reductions over time (P < 0.001), significant differences among the four experimental conditions (P < 0.001) and a significant condition x time interaction (FEV1:P < 0.001, MMEF:P < 0.01). FEV1 was significantly lower for CC and WC, as compared with WW and CW at 5 and 10 min postexercise. The lowest postexercise values for FEV1 occurred in the CC and WC sessions (76% predicted in both). A similar pattern was obtained for MMEF. Facial cooling combined with either cold or warm air inhalation causes the greatest EIB, as compared with the isolated challenge with cold air inhalation. We suggest that vagal mechanisms play a major role in exercise and cold-induced bronchoconstriction.

Screening of athletes for exercise-induced bronchoconstriction.

Exercise-induced bronchoconstriction (EIB) has a high prevalence in elite athletes, particularly endurance athletes, winter athletes and swimmers. Recent studies have shown that a clinical diagnosis of EIB has only a moderate sensitivity and specificity for EIB. This finding in conjunction with a recent ruling by the IOC-medical commission that all athletes competing in initially the 2003 Winter Olympic Games in Salt Lake City, and now the 2004 Summer Olympic Games in Athens require objective evidence of EIB, support the need for bronchial provocation challenge tests in the diagnosis of EIB. The recommended bronchial provocation challenge test is the eucapnic voluntary hyperpnea (EVH) challenge; this challenge test has been shown to have both a high sensitivity and specificity for EIB. Pharmacological challenge tests, such as the methacholine challenge test, have been shown to have only a low sensitivity but high specificity for EIB in elite athletes, and are thus not recommended in the athlete with pure EIB. Exercise challenge tests performed both in the laboratory and field have a high specificity for EIB; however those in the laboratory have only a moderate sensitivity for EIB in elite athletes, whilst those in the field are limited by problems with standardization. The osmotic challenge tests, such as the hypertonic saline and newer inhaled dry powder mannitol challenge have both a high sensitivity and specificity for EIB, and may be used as an alternative to the EVH challenge.

Airway Hyperresponsiveness by Methacholine Challenge Testing Following Negative Exercise Challenge

Background. Exercise challenge testing (ECT) to diagnose exercise‐induced bronchospasm has been demonstrated to be an insensitive screening test to demonstrate the presence or absence of airway hyperreactivity. Previous studies have not compared this procedure to methacholine challenge testing (MCT) in a clinical setting. Objective. To determine the frequency of positive MCT in subjects with exertional dyspnea, normal baseline spirometry, and negative ECT. Methods. Observational study of 215 military patients at an Army Community Hospital referred for evaluation of exertional dyspnea with normal baseline spirometry. Subjects were further evaluated with ECT on a graded treadmill with pre‐ and postexercise spirometry. Those without evidence of bronchial hyperreactivity as defined by a 15% decrease in FEV1 postexercise were evaluated with methacholine challenge testing (MCT). Results. Two hundred ten military subjects were evaluated. Eighty‐two patients underwent ECT as the only method of bronchoprovocation testing with 25 positive tests (57 were negative but not referred for further testing). The remaining 128 patients with a negative ECT underwent MCT. Seventy‐six (59%) had a negative MCT and 52 (41%) had a positive MCT. Of the positive MCT studies, 74% were positive at a methacholine concentration of 2.5 mg/mL or less. Conclusions. Our study demonstrates that a significant number of patients being evaluated for exertional dyspnea will have a positive MCT after a negative ECT. Our findings lead us to question the utility of ECT as an initial diagnostic test for the exercise‐induced bronchospasm.

Quality of life in adolescents with mild asthma

The majority of individuals with asthma have mild disease, often in conjunction with allergic rhinitis and exercise-induced bronchoconstriction (EIB). Although health-related quality-of-life (HRQoL) is reduced in moderate to severe asthma and allergic rhinitis, little is known about the effect of mild asthma, mild allergic rhinitis, and EIB on HRQoL outcomes. The objective of this study was to determine the effect of mild asthma, allergic rhinitis, and EIB on HRQoL. A cross-sectional study was conducted of 160 adolescent athletes participating in a screening program to detect EIB. Generic HRQoL was assessed with the teen version of the pediatric quality-of-life inventory (PedsQL). Prior diagnoses of asthma, allergic rhinitis, and EIB, and current symptoms of dyspnea during exercise and asthma, were recorded. Lung function and the presence of EIB were determined by spirometry before and after an exercise challenge test. Adolescent athletes with a prior physician diagnosis of asthma had a lower HRQoL scale summary score (P<0.01) and lower physical functioning, emotional functioning, and school functioning domain scores (P values, 0.01-0.02) in comparison to adolescent athletes with no prior diagnosis of these disorders. Athletes with a prior diagnosis of asthma reported dyspnea during exercise more frequently than did those without asthma (P<0.001). Adolescent athletes with dyspnea during exercise had a lower scale summary score, and lower physical functioning, general well-being, and emotional functioning domain scores (P values, 0.02-0.03). These data show that mild asthma and dyspnea without asthma significantly affect HRQoL. Symptoms of dyspnea during exercise are common in asthma and are associated with lower HRQoL. The clinical significance of these differences in HRQoL is unclear.

Anafilaxia inducida por ejercicio tras ingesta de manzana

hematimetries, biochemistries, VMA and 5-HIAA in urine. Complement levels, antinuclear antibodies and viruses serology. skin prick test with a common inhalant. Skin prick test and prick by prick with different foods. Total Ig E level and specific Ig E determination by the CAP-Pharmacia System. Oral challenge test with apple, exercise test and exercise challenge test after eating an apple. Prick by prick test with fresh apple was positive. Specific Ig E determination by the CAP-Pharmacia System revealed a positive result. We get to reproduce the episode with an exercise challenge test after eating an apple in the same conditions of usual exercise in both patients.

A randomized, double-blind, single-dose, crossover clinical trial of the onset and duration of protection from exercise-induced bronchoconstriction by formoterol and albuterol

Background: Inhaled short-acting beta 2-adrenoceptor agonists are the most commonly used treatment for the prevention of exercise-induced bronchoconstriction (EIB). Formoterol, a long-acting beta 2-adrenoceptor agonist, has been demonstrated to provide protection from EIB, although the onset and duration of this protection have not been defined. Objective: The purpose of this study was to determine the onset and duration of the protective effect of a single dose of inhaled formoterol powder against EIB, comparing them with the effect of a single dose of placebo and albuterol administered via metered-dose inhaler (MDI). Methods: In this double-dummy, 4-way crossover study, patients received single doses of formoterol (12 and 24 μg) via a powder inhaler, albuterol by MDI (180 μg), and placebo. Exercise challenge tests (ECTs) were conducted at 15 minutes and at 4, 8, and 12 hours postdose. Pulmonary function studies (forced expiratory volume in 1 second [FEV 1] and peak expiratory flow rate) were performed before and after each exercise challenge. Results: Twenty adolescent and adult patients (mean age, 23.8 years; range, 13–41 years; 9 male, 11 female) with asthma were enrolled in the study, and 17 completed all 4 treatment sequences. Compared with placebo, both doses of formoterol produced significantly greater inhibition of FEV 1 decreases at all time points ( P < 0.01). There were no significant differences in efficacy measures between the 2 formoterol doses throughout the study. The exercise-induced decrease in FEV 1 after albuterol treatment was significantly reduced compared with placebo only at 15 minutes after dosing ( P < 0.05). Formoterol and albuterol exhibited a similar rapid onset of action (<15 minutes), but formoterol continued to protect patients against EIB for at least 12 hours ( P < 0.01), whereas albuterol was no longer clinically effective by the 4-hour ECT. Conclusions: Formoterol and albuterol, given as single-dose inhalations, both provided protection from EIB within 15 minutes in this group of patients. The bronchoprotection afforded by formoterol lasted up to 12 hours, whereas that of albuterol was no longer significant by 4 hours.

Formoterol provides long-lasting protection against exercise-induced bronchospasm

Patients with exercise-induced bronchospasm (EIB) may benefit from a prophylactic beta2-adrenergic agonist that combines rapid onset with long duration of action. To compare the protective effect against EIB of a single inhaled dose of formoterol powder delivered via the Aerolizer inhaler (Novartis Pharmaceuticals, East Hanover, NJ) with the effect of placebo and albuterol. Eighteen patients with EIB were randomized to treatment in a double-blind, placebo-controlled, four-way, crossover study. Seventeen patients completed all four crossover periods. Each patient received in random sequence a single dose of formoterol (12 or 24 microg), albuterol (180 microg), or placebo at intervals of 5 +/- 2 days. Pulmonary function measurements were taken before and after exercise challenge tests (ECTs) at 15 minutes postdosing and at 4, 8, and 12 hours postdosing. Both doses of formoterol produced significantly greater protection against EIB, compared with placebo, at all timepoints (P < or = 0.016). The two doses of formoterol were not significantly different from one another at any time. Protection against EIB with albuterol was clinically significant only for the 15-minute ECT and was statistically superior to placebo for the 15-minute and 4-hour ECTs. Although formoterol and albuterol exhibited a rapid onset of action, formoterol provided longer-lasting protection over the 12-hour observation period. Rescue medication was used substantially less with either dose of formoterol, compared with albuterol or placebo. All treatments were well tolerated. Two-hour postdosing electrocardiograms and vital signs were unremarkable for all study treatments. A single dose of formoterol (12 or 24 microg) provides protection against EIB within 15 minutes of dosing and persists for up to 12 hours. Formoterol is safe and well tolerated.

Value of a Negative Aeroallergen Skin-Prick Test Result in the Diagnosis of Asthma in Young Adults: Correlative Study With Methacholine Challenge Testing

None of the existing tests for the diagnosis of asthma are considered to be definitive. Certain circumstances require prompt diagnosis, and a test able to predict the absence of asthma would be very useful. To evaluate the contribution of a skin-prick test (SPT) to the diagnostic workup of subjects with suspected asthma. The study included three groups of subjects aged 18 to 24 years: group A, asthmatic patients (n = 175); group B, control subjects (n = 100); and group C, subjects with suspected asthma (n = 150) with normal spirometry findings and a negative exercise challenge test result. All underwent an SPT to a battery of common aeroallergens, and group C underwent a methacholine challenge test (MCT) in addition. The sensitivity, specificity, positive predictive value, and negative predictive values (NPV) of the SPT were calculated using provocative concentrations of methacholine causing a 20% fall in FEV(1) (PC(20)) of < 4 mg/mL and < 8 mg/mL as diagnostic cutoff values for asthma in the MCT. Bayes' formula was used to determine posttest probabilities of having asthma, both for positive and negative SPT results. A positive SPT result to at least one allergen was found in 95.5%, 54%, and 69% of patients in the three groups, respectively. The sensitivity, specificity, and NPV of the SPT were 90.7%, 52.0%, and 84.8%, respectively, with a cutoff value of PC(20) < 8 mg/mL. The lower cutoff, PC(20) < 4 mg/mL, increased the sensitivity and NPV to 98.2% and 97.8%, respectively. A negative SPT result decreased the probability of having asthma by 10-fold to 20-fold in subjects whose pretest probability was low to moderate. Incorporating an SPT into the workup of subjects with suspected asthma can reduce the cost of this process significantly. The SPT may be used as a simple, fast, safe, inexpensive, and reliable method to predict the absence of asthma in young adults.

Effects of air pollution on changes in lung function induced by exercise in children with chronic respiratory symptoms

Objective: To investigate how daily variations in ambient air pollution, especially in particles, during the cold of winter affect repeated measurements of baseline lung function and exercise induced bronchial responsiveness...

Methacholine, cold air and exercise challenge tests in the diagnosis of bronchial responsiveness at school age: A follow-up study from birth to school age

ABSTRACT Background The aim of the present study was to compare three bronchial challenge tests for assessing bronchial hyperresponsiveness (BHR) in twin pairs followed up from birth to school age. Methods We studied three different bronchial challenge tests (methacholine inhalation challenge, cold air inhalation challenge and exercise-bronchodilation tests) at school age in 29 children born at or before 38 weeks gestation (median 35 weeks gestation) from multiple pregnancies. The children had been followed up from birth and were examined at the age of 7-15 years (median age 10 years). Results Bronchial hyperresponsiveness was found in 28-34% of children when these tests were analyzed separately. Eight children (28%) were exercise responders; two of them and three additional children were bronchodilator responders. Thus, 11 children (38%) had a pathologic result in the exercise-bronchodilation test. Ten children (34%) responded to cold air and nine children (31%) responded to methacholine inhalation. At least one test was pathologic in 18 children (62%), but only two children (7%) responded in all three challenges. A positive result in the exercise-bronchodilation test was associated with cold air reactivity, but not with methacholine reactivity. The exercise and cold air tests detected predominantly the same children. No differences were found in bronchial challenge test results between children who, at birth, were appropriately grown and those who had intrauterine growth retardation. conclusions Bronchial hyperresponsiveness was common (up to 62%) at school age in children born as moderately preterm. The outdoor exercise-bronchodilation test found 61% of all BHR cases. Bronchial hyperresponsiveness was not associated with intrauterine growth status. The most sensitive test was the cold air inhalation challenge and a good agreement was seen between this test and the exercise challenge outdoors.

Exercise-induced bronchoconstriction among Malay schoolchildren.

Exercise-induced bronchoconstriction (EIB) may be demonstrated in 60-70% of asthmatic children in temperate climates. In areas of high humidity it is postulated to be low. The aim of the study was to determine the prevalence of EIB in a population of schoolchildren with wheezing, living in the humid tropical climate of Kuala Lumpur, Malaysia. We performed a cross-sectional study using the International Study of Asthma and Allergies in Childhood questionnaire to identify 7-12-year-old Malay children with asthma symptoms from a primary school in central Kuala Lumpur. Sixty-five of 76 children with 'ever wheeze' performed an exercise challenge test successfully in an uncontrolled environment. A random sample of 80 schoolchildren with no history of wheeze were similarly tested as controls. The relative humidity and temperature were recorded. A fall of > 15% was considered as clinically important. The prevalence of EIB in schoolchildren with 'ever wheeze' was 47.7%. The prevalence of EIB in children with 'current wheeze' was 51.6%. The prevalence of EIB in controls was 7.5%. The relative humidity during the study ranged from 41 to 90%. There was no significant relationship between different humidity levels and EIB (P = 0.58, regression analysis). This study demonstrates that EIB is present in asthmatic children despite the highly humid tropical environment.

The Prevalence of Exercise-Induced Bronchospasm Among US Army Recruits and Its Effects on Physical Performance

To measure the prevalence of exercise-induced bronchospasm (EIB) and to determine its effect on the physical performance response to training in otherwise healthy young adults. Observational, retrospective study. Fort Jackson, SC, May to July 1998. One hundred thirty-seven ethnically diverse US Army recruits undergoing an 8-week Army basic training course. Subjects underwent exercise challenge testing at the end of basic training to evaluate for EIB (defined as a decrease in FEV(1) of > or = 15%, 1 or 10 min after running to peak oxygen uptake on a treadmill). Those subjects who were unable to run to peak oxygen uptake, or who were unable to perform two baseline FEV(1) maneuvers the results of which were within 5% of each other, were excluded from analysis. We measured peak oxygen uptake on a treadmill and the scores achieved on the components of the US Army physical fitness test (APFT). Of 137 subjects, 121 (58 men and 63 women) met our inclusion criteria. Eight subjects (7%) had EIB. Subjects who experienced EIB and unaffected control subjects both showed statistically significant gains in performance on the APFT events during basic training. At the end of basic training, peak oxygen uptake levels and APFT event scores were not significantly different between subjects with EIB and unaffected control subjects. Seven percent of the US Army recruits who were tested had EIB, but this did not hinder their physical performance gains during basic training. EIB per se should not be an absolute reason to exclude individuals from employment in jobs with heavy physical demands.

EFFECTS OF NITRIC OXIDE SYNTHASE INHIBITION IN LUNG FUNCTION DURING EXERCISE IN ASTHMATICS

Upon cessation of exercise, pulmonary resistance (RL) and forced expired volume in one second (FEV1) significantly deteriorate in individuals with exercise-induced asthma. However, lung function during exercise is relatively well preserved. Nitric oxide (NO) is a known bronchodilator that might have a protective effect during exercise. METHODS We evaluated changes in RL during 20 min moderate intensity exercise in 17 subjects with FEV1 91% ± 16% predicted and a positive exercise challenge test (reduction in FEV1>15% after exercise breathing dry air). RL was assessed before, during, and up to 15 min after the 20-min exercise on two days; subjects were treated with a nebulized NO synthase inhibitor LNMMA (Ng-monomethyl-L-arginine, 50mg in 2mL saline) or saline in random order, double blinded. RESULTS LNMMA increased RL (81% ± 78% on LNMMA day vs 6.6% ± 28% on saline day, P < 0.01). A decline in RL early in exercise was not prevented by LNMMA, and post exercise increase in RL was similar on the two days (table). There was a slow rise in RL during exercise that was the same on the two days (0.061 ± 0.063 for saline, 0.078 ± 0.078 for LNMMA, units cmH2O/L/sec per min of exercise).TableCONCLUSIONS Our results suggest that NO might regulate baseline airway tone, but it is not further involved in the control of airway function during or after exercise. A dilator influence is present early in exercise, which might be related to mechanical effect of increased tidal volume or respiratory rate. Supported by NIH grants HL52230 and NIH RR-00585

Síndrome de anafilaxia inducida por ejercicio

In the last two decades a growing incidence of a peculiar form of anaphylaxis that only occurs while carrying out physical exercise has been observed. Within the exercise-induced anaphylaxis syndrome two well differentiated clinical forms are included: systemic cholinergic urticaria and exercise-induced anaphylaxis in the strict sense which can be shown by a classic form or a variant form, more uncommon and with manifestations similar to cholinergic urticaria. Postprandial or food-dependent exercise-induced anaphylaxis is a frequently identified subtype of these last cases. It can be due to an asymptomatic food allergy manifested through physical effort, although in many occasions it is not possible to find a responsible allergen. The diagnosis is settled on the clinical history and specific tests with food allergens. It can be necessary to perform an exercise challenge test with and without previous ingestion. The treatment is preventive and it is based on avoiding the food or the food allergen some hours before the exercise. When it does not depend on foods it is used a prophylactic pharmacotherapy with antihistamines, cromones or sodium bicarbonate. The patient should be well educated on the use of epinephrine in the event of new reactions.

Sports and Asthma

Whereas exercise-induced bronchospasm (EIB) is common among asthmatics, exercise-induced asthma (EIA) may occur in otherwise healthy individuals, particularly athletes. Baseline pulmonary function testing (PFT) should be obtained in all suspected cases. It may be advisable to screen highly competitive athletes who might be at a higher risk for EIA/EIB than average. The mechanism of EIA/EIB may involve airway cooling and rewarming and/or airway drying with mediator release. The mainstay of treatment is short-acting inhaled bronchodilators prior to exercise, in addition to regularly used anti-inflammatory agent, if required. Pre-exercise warm-ups may be helpful, at least in part. The diagnosis should be confirmed with exercise challenge testing for individuals who do not respond to treatment. These individuals may have alternate diagnoses. (Pediatr Asthma Allergy Immunol 2000; 14[4]:269–276.)

Formoterol via Turbuhaler®gave better protection than terbutaline against repeated exercise challenge for up to 12 hours in children and adolescents

We aimed to compare the protective effect of single doses of 4·5 and 9 μ g of formoterol fumarate (F), 0·5 mg terbutaline sulphate (T) and placebo (P), all via Turbuhaler®, against exercise-induced bronchoconstriction (EIB) in children.Twenty-seven asthmatic children, showing a fall of ≥20% in FEV1after a standardized exercise challenge test (ECT) combined with cold air (−10°C) inhalation, were randomized in this cross-over, double-blind study. They had a mean age of 12·6 years (range 8–17 years), mean baseline FEV190% (73·9–105·6%) of predicted normal value. Seventeen children used inhaled glucocorticosteroids (120–750 μ g day−1). ECTs were performed 15 min and 4, 8, and 12 h after drug administration.F significantly reduced the fall in FEV1after ECT to 5·4% (15 min), 5·2% (4 h), 8·2% (8 h) and 9·3% (12 h) after 4·5 μ g, and 2·5%, 3·0%, 5·0% and 5·4% after 9 μ g, compared with a fall of 18·4%, 15·7%, 15·6% and 16·5% in FEV1after P. The fall after T was 3·3%, 11·6%, 14·4% and 19·1% after 15 min, 4, 8 and 12 h respectively. The difference between F and T was statistically significant from 4 h and onward (P -value for all comparisons <0·05).Children using a single dose of either formoterol Turbuhaler 4·5 or 9 μ g had significantly better bronchoprotection against repeated exercise challenge up to 12 h compared with placebo and from 4 h onward compared with terbutaline Turbuhaler®0·5 mg.

Guidelines for Methacholine and Exercise Challenge Testing—1999

Guidelines for Methacholine and Exercise Challenge Testing—1999

Short term effects of aerobic training in the clinical management of moderate to severe asthma in children

BACKGROUNDAerobic training has a number of well known beneficial effects in both normal and asthmatic children. However, the impact of training on the clinical management of the underlying bronchial asthma...