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Objective. Bronchial hyperresponsiveness is usually measured by bronchial challenge with direct (e.g. methacholine) and indirect (e.g. adenosine) agonists. A prospective, randomized, crossover, single-blind study was performed to compare both methods in the first diagnosis of asthma. Patients and methods. Fifty-seven patients, in which asthma was suspected, were selected (21 male, 36 female). Fifty-four underwent both challenges following the five-breath dosimeter protocol. PC20 was calculated according to ATS guidelines. Data of symptoms developed during the challenge, PC20 methacholine and adenosine, and FEV1 improvement after bronchodilator therapy were recorded. Results. Symptoms at consultation were consistent with asthma in 68.4% patients, asthma and rhinitis in 29.8% and exercise-induced asthma in 1.8%. Atopy was reported in 93%; 49.1% had family history of atopy and 26.3% of asthma. The most frequent symptoms developed during the challenge were cough (40.4% with adenosine and 20.4% with methacholine) and wheezing (26.3% and 7.4% respectively), statistically significant differences. Bronchial challenge with MCh resulted positive in 44.4% of the patients and positive with AMP in 50%. Every patient with negative result to adenosine, was also negative to methacholine. In 94.4% subjects the result of both challenges was concordant (kappa index = 0.889). PC20 in both challenges showed poor linear correlation (Pearson r = 0.43, p < 0.05). Positivity of both challenges was only associated with having a positive skin prick test to danders (p = 0.001). Percentage of improvement after bronchodilator was 34.9% (SD12.2%) with adenosine challenge and 33.9% (SD17.9%) with methacholine (differences non statistically significant). Conclusions. Concordance in the result of both techniques is very high. Cough and wheezing are more frequent with adenosine, though not severe. PC20 with both techniques shows poor linear correlation. [ABSTRACT FROM AUTHOR]

Background. Various factors have been reported to be useful for predicting future exacerbations. Objective. This study was intended to determine a usefulness of a combination of a patient-based questionnaire, such as the Asthma Control Test (ACT) score with objective assessments, such as forced expiratory volume in 1 second (FEV1) and/or exhaled nitric oxide (FENO), for predicting future exacerbations in adult asthmatics. Methods. We therefore enrolled 78 subjects with mild to moderate asthma, who were clinically stable for 3 months who all had been regularly receiving inhaled steroid treatment. All subjects underwent a routine assessment of asthma control including the ACT score, spirometry, and FENO, and then were followed up until a severe exacerbation occurred. The predictors of an increased risk of severe exacerbation were identified and validated using decision trees based on a classification and regression tree (CART) analysis. The properties of the developed models were the evaluated with the area under the ROC curve (AUC) (95% confidence interval [CI]). Results. The CART analysis automatically selected the variables and cut-off points, the ACT score ≤23 and FEV1 ≤ 91.8%, with the greatest capacity for discriminating future exacerbations within one year or not. When the probalility was calculated by the likelihood ratio of a positive test (LP), the ACT score ≤23 was identified with a 60.3% probability, calculated by 1.82 of LP, whereas the combined ACT score ≤23 and the percentage of predicted FEV1 ≤ 91.8% were identified with an 85.0% probability, calculated by an LP score of 5.43, for predicting future exacerbation. Conclusion. These results demonstrated that combining the ACT score and percentage of predicted FEV1, but not FENO, can sufficiently stratify the risk for future exacerbations within one year. [ABSTRACT FROM AUTHOR]

Background. Inhaled corticosteroids (ICS) are used in asthma therapy for their anti-inflammatory effects. P-glycoprotein (PGP) is a transmembrane efflux pump for many drugs, including corticosteroids. Expression of PGP is associated with therapy resistant disease. Objective. The purpose of this study was to compare expression levels of PGP in blood lymphocytes of pediatric asthma patients either on ICS or on the leukotriene inhibitor montelukast medication. Patients and Methods. The evaluation of lymphocyte PGP expression was performed on a sample of 99 children (66 boys and 33 girls) aged 2-18 (median 12) years with intermittent or persisting mild asthma, (as defined by GINY 2002). The asthmatic children were divided into 3 groups: (1) treated by ICS budesonide 200-400 μg per day (n = 27) more than 1 year; (2) treated by oral montelukast 4 or 5 mg at an age-based dose (n = 16); and (3) treated by inhaled corticosteroids and montelukast (n = 45). Reference PGP values were obtained from a group of 64 healthy children (23 boys and 29 girls) aged 2-15 years (median, 10 years). The expression of lymphocyte PGP was determined on fixed and permeabilized blood mononuclear cells using indirect immunofluorescence staining technique by flow cytometry modified according to Boer et al., 1997. Results. Based on the weighted medians for PGP expression in peripheral blood lymphocytes, we found a significant difference (p < 10-3) between the group of asthma patients (n = 99), (619 ± 5.3) and healthy controls (n = 64) (446.9 ± 4.4). Second, there was a lower level of PGP expression in the group treated by ICS (548.6 ± 9) than the group treated by montelukast and montelukast with budesonide (643.2 ± 6.3) (p < 10-6). Conclusions. The anti-inflammatory activity of ICS is more effective in decreasing the production of pro-inflammatory mediators and results in reduced multidrug resistence (MDR-1) gene activity and expression of lymphocyte PGP in asthmatic children. [ABSTRACT FROM AUTHOR]

Adenosine monophosphate (AMP) challenge is a diagnostic tool for asthma. The aim of this study is to evaluate the effect of low dose inhaled budesonide (IB) on PC20AMP levels. Seventeen stable mild asthmatic patients were prospectively recruited. After initial testing, patients were administered 400 μ g of inhaled budesonide. AMP challenge was then repeated at the 12th hour and 5th,15th, 30th, and 90th days of the treatment. AMP challenge resulted in negative in 47% of the patients at 12-hour testing. This study suggests that low-dose IB may return airway responsiveness as early as 12 hours and AMP challenge may be effectively used for treatment monitorization. [ABSTRACT FROM AUTHOR]

There are a number of useful direct airway sampling procedures to help diagnose and monitor asthma in patients. However, non-invasive techniques are the ideal, especially in children, given the necessity of safe and repeatable measurements to monitor treatment efficacy and disease progression. Bronchoalveolar lavage (BAL) may be too invasive for clinical use in children, while questions still surround the utility of induced sputum (IS). More novel techniques, such as fractional exhaled nitric oxide (FENO) and exhaled breath condensate (EBC), are still unproven. Eosinophilic airway inflammation is a major feature of childhood asthma, and it has been revealed as a major treatment target with inhaled corticosteroids. Moreover, treatment protocols governed by sputum eosinophil counts may be more efficacious - by reducing the frequency and severity of exacerbations - than treatment based on clinical symptoms and other traditional objective measures of lung function. The selection of an appropriate airway inflammation monitoring technique must take everything into consideration, including safety, reproducibility, repeatability, sensitivity to treatment, and the overall clinical/research goals. [ABSTRACT FROM AUTHOR]

Rationale. Negative affectivity is a measure of anxiety associated with increased reporting of symptoms. Few studies have explored this association with respect to drug-induced symptoms in patients taking medication for a chronic disease in real life. Objectives. In this cross-sectional study we examined the relationship between negative affectivity and self-reported side effects of inhaled corticosteroids in patients with asthma. We also investigated differential associations due to side effect type (subjective versus observable side effects) and treatment impact (i.e., hierarchical dosing). Methods. A total of 228 asthma patients, taking inhaled corticosteroids, completed scales measuring inhaled corticosteroid-induced side effects (Inhaled Corticosteroid Questionnaire scored: 0 = none; 100 = worst) and negative affectivity (Positive and Negative Affect Schedule scored: 10-50). Patients were grouped into low, average, and high negative affectivity groups based on published norms. Results. Patients high in negative affectivity reported significantly greater (p < 0.001) side effects (median score 20.5 (IQR: 11.4-33.0) than the groups of patients scoring lower on this measure (low negative affectivity: 7.1 (3.1-15.6); average: 13.3 (4.9-23.3)). The relationship between negative affectivity and side effects was stronger among patients taking low (r = 0.40-0.45) rather than mid to high inhaled corticosteroid doses (r = 0.16-0.28). Conclusions. Asthma patients with higher negative affectivity using inhaled corticosteroids report increased medication-induced symptoms. Clinicians should be aware that aside from inhaled corticosteroid dosage, the personality of the patient is an important factor in the reporting of drug-related side effects. [ABSTRACT FROM AUTHOR]

Background and aim: Asthma is a variable disease, and therapy should be tailored accordingly. The aim of this study was to explore patterns of self-management in response to disease variability in adult asthmatics. Methods: Adult asthmatics (n = 509), recruited through a web-based panel, answered a questionnaire concerning asthma knowledge, compliance, and treatment, including specified treatment options, through the Internet. Results: Two-thirds of the patients on inhaled corticosteroids (ICS) stepped-up and down their daily dose without prior contact to their doctor, and more than 50% took less ICS than prescribed during periods with fewer symptoms. In case of deterioration, 57% of the patients would only increase their reliever medication, whereas 23% would also increase their controller medication, although 59% were instructed by their doctor to do so. The self-perceived severity of asthma (graded as mild, moderate or severe) was not associated with the patients' response pattern. The preferred treatment strategy, differing primarily with regard to dosing and timing of controller medication, was associated with feeling safe about self-adjustment of controller medication (p < 0.001), but not with self-reported knowledge of asthma (p > 0.5). Conclusion: In case of deterioration, the majority of adult asthmatics only increase their reliever medication, although instructed by their doctors also to increase their controller medication. Furthermore, the patients' preferred strategy for management of disease variability seems not to be driven by their knowledge of the disease. [ABSTRACT FROM AUTHOR]

Background: Inhaled corticosteroids (ICSs) are the most effective anti-inflammatory drugs for adult asthma and can improve not only clinical symptoms but also bronchial hyperresponsiveness (BHR). However, the prognosis of adult asthma has not been well studied, and it remains to be elucidated precisely how long treatment with ICSs should be continued once clinical remission is achieved. Objectives: We examined whether ICS use could be withdrawn or reduced without exacerbation of disease. Methods: We retrospectively studied 374 adult patients with asthma to determine which factors predicted the elimination or reduction of ICS treatment without exacerbations of disease after the achievement of normalized BHR to acetylcholine. The patients were classified into three groups: Group 1 had symptoms within 6 months of normalization and needed to continue therapy; group 2 received the equivalent of ≥ 400 μ g fluticasone propionate until BHR normalization, did not have symptoms in the 6 months after normalization, and then had their doses of ICSs halved; and group 3 received the equivalent of ≤ 200 μ g fluticasone propionate at an enrollment, did not have symptoms in the 6 months after normalization, and then had all ICSs withdrawn. The primary outcome measure was the presence of clinical symptoms. We used multiple logistic regression and a Kaplan-Meier analysis to analyze the factors predicting remission. Results: Twenty-nine patients in group 3 remained asymptomatic for more than 30 months (mean 47.1 ± 12.4 months) after discontinuing ICS therapy. The predictive markers of remission were low levels of eosinophils in the sputum, high %V50 at the first hospital visit, and the need for only a low daily dose of ICS to induce normalized BHR. Conversely, patients with severe BHR at the first hospital visit, low %FEV1 at normalized BHR, and a need for high-dose ICSs to reach normalized BHR could not reduce or discontinue treatments. Conclusion: Some adult patients with asthma whose BHR is normalized by ICS therapy can achieve remission from disease exacerbation after discontinuation of ICSs. However, patients with severe asthma or asthma of long duration may not achieve remission even if their BHR is normalized. [ABSTRACT FROM AUTHOR]

Knowing about spontaneous variations in the fractional concentration of exhaled nitric oxide (FENO) could improve monitoring of airway inflammation in asthmatic children. We aimed to assess FENO variations (expiratory flow 50 mL/sec) in subjects maintained in similar environmental conditions. We tested spirometry and FENO in symptom-free asthmatic children (9 corticosteroid-naive, 8 corticosteroid-treated) during a 1-week stay in a countryside sanatorium and in their healthy relatives (n = 12) staying in the immediate neighborhood on summer holiday (total 29 children, M/F:14/15, 5.8-16.8 yrs). Testing sessions were repeated every 12 hours (8:00 am, 8:00 pm) for 2 days and again on day 7. Measurements were defined as reproducible when they agreed with an intraclass correlation coefficient (ICC) above 0.60; deviation from mean differences was assessed by the coefficient of repeatability (CR = 2 SD). Lung function remained constant throughout the week in all groups. Baseline FENO levels in corticosteroid-naive asthmatic children tended to decrease at the end of the week (from 13.9 ppb, 95% CI 12.2-19.1 to 9.2 ppb, 95% CI 5.8-15.9, p = 0.057). No differences were found between nocturnal and diurnal FENO. Within-session reproducibility for two FENO measurements was high (ICC 0.99 in all groups and CR, 0.9 to 1.3 ppb). Between-session FENO reproducibility at 12 hours and 24 hours was still high for each group but decreased markedly after 6 days in corticosteroid-naive asthmatic children (ICC 0.79 and CR 9.6 ppb at 24 hours vs. ICC 0.13 and CR 20.8 ppb after 6 days), whereas it decreased slightly in corticosteroid-treated asthmatics (from ICC 0.89 and CR 3.1 ppb to ICC 0.88 and CR 3.0 ppb) and healthy children (from ICC 0.79 and CR 4.8 ppb to ICC 0.65 and CR 5.7 ppb). In conclusion, in healthy subjects and in asthmatic children receiving therapy with inhaled corticosteroids (but not in corticosteroid-naive subjects), FENO measurements are reproducible across a week. [ABSTRACT FROM AUTHOR]

Objective. This pilot study explores the reported symptoms in African Americans and Caucasians with asthma. Methods. Asthma patients in an inner-city pulmonary clinic were given a brief questionnaire of asthma symptoms and the BORG scale, followed by spirometry. Results. African Americans were less likely to report nocturnal awakenings (67% vs. 100%; p = 0.037), complain of dyspnea (33% vs. 75%; p = 0.038), or experience chest pain (13% vs. 75%; p = 0.002) than Caucasians. Conclusions. This is the first study to demonstrate that there are clinically significant differences in the reporting of asthma symptoms between African Americans and Caucasians. [ABSTRACT FROM AUTHOR]

Purpose: To quantify the association between cardiovascular disease (CVD) and asthma in Canadian adults and to determine whether age of asthma onset is a moderator of this association. Methods: We used a sample of 74 342 participants with a mean age of 56.4 ± 12.5 from cycle 1.1 of the Canadian Community Health Survey. Asthma age of onset was categorized into early-onset (0-20 years) and adult-onset (21-54 years). Three major outcomes were used to estimate the relationship between asthma and CVD, namely: high blood pressure, heart disease, and stroke. Results: Multiple logistic regression models revealed that asthmatics were 43% (OR = 1.43, CI = 1.19-1.72) more likely to have heart disease, and 36% (OR = 1.36, CI = 1.21-1.53) more likely to have high blood pressure than non-asthmatics. There were no consistent results for age of onset with high blood pressure, heart disease, or stroke. Conclusion: Using a population-based dataset we confirmed that asthmatics are at increased odds of cardiovascular disease compared to non-asthmatics; furthermore, age of asthma onset did not appear to moderate this relationship. Future research should focus on determining whether asthma severity or allergic/non-allergic phenotypes have a differential effect on the asthma-CVD relationship. [ABSTRACT FROM AUTHOR]

This prospective exploratory story examined diurnal variations in pulmonary function and their association with sleep and quality of life (QOL) in 20 adult asthmatics. Peak expiratory flow (PEF) was assessed for 7 days, before bedtime and upon awakening. There was no association between PEF variability and QOL. Six of 13 polysomnographic measures were significantly correlated with overnight decline in PEF. Individuals with greatest decline took longer to fall asleep and enter Stage 1 sleep, spent less time asleep, and experienced poorer sleep efficiency. Diurnal variations in PEF reflect adverse sleep quality, yet impact on QOL is often unnoticed. [ABSTRACT FROM AUTHOR]

Self-reported symptoms, FEV1, and clinician judgment are all used to evaluate asthma control. The relative utility of each measure of control cannot be easily assessed. Item response theory (IRT) approaches allow for the direct comparison of the utility of different types of measures used to assess control. The objective of this study was to evaluate the validity and reliability of evaluating asthma control using symptom, clinical, and physiologic measures by applying an IRT approach. Subjects receiving care at an asthma clinic were evaluated on measures of asthma control. Based on 114 evaluations, IRT parameters were estimated to evaluate whether measures assessed a single underlying construct, the hierarchical relationship between the measures and the level of control each measure assessed, whether measures targeted all levels of asthma control, and whether the scoring categories distinguished between different levels of control. Infit statistics (0.74-1.5) for individual items showed that all items fit the underlying concept of asthma control. The reproducibility of the hierarchal scale was high (0.9). The results also demonstrated that items differentiated two strata (high, low) of control. The gaps in the hierarchal scale showed that for many subjects (37%) there were no items at their level of asthma control. The IRT approach identified gaps in current measurement that need to be addressed to provide more precise evaluations of control required to accurately monitor changes in patient status. [ABSTRACT FROM AUTHOR]

The aim of this study was to validate the QUOTAC, a questionnaire on day and night time respiratory symptoms in asthmatic children. Validity was examined by measuring agreement between the QUOTAC and a self-report diary in children aged 6 to 16 years, divided in an asthma group and a control group. As an extra interest in our study a sum score was computed as a measure of the severity of asthma. This study shows that the QUOTAC is discriminative between asthmatic and healthy children and is a reliable and sensitive scale for measuring the severity of asthma. However, cut-off scores for mild, moderate, or severe asthma should be investigated in further research. [ABSTRACT FROM AUTHOR]

Exercises testing and cold air challenges are frequently used to assess airway hyperresponsiveness (AHR), but different goals are set for the two tests. We, therefore, wished to determine whether cold air and exercise challenge testing yielded similar responses and if any differences were due to differences in the maximum minute ventilation achieved. Twenty asthmatic subjects each performed a cold air (CACh) and an exercise (EXCh) challenge. Baseline forced expiratory volume in one second (FEV1) was recorded immediately pre-challenge and then serially for at least 10 minutes post-challenge. The maximum minute ventilation achieved was recorded. In the subjects who had at least a decrease in FEV1 of 15% in response to the first CACh, a second CACh was performed, but at the maximum minute ventilation achieved during EXCh. Eleven subjects after CACh and four after EXCh had a greater than 15% decrease in FEV1 (p = 0.05). The median decrease in FEV1 was greater following the CACh (16.7%[25th to 75th percentile 10.4 to 19.9]) than the EXCh (6.9%[25th to 75th percentile 4.3 to 14.6]); (p = 0.0004). The median maximum minute ventilation achieved was greater with the CACh (89[66-141] L/min) than with the EXCh (61(40 to 102)L/min); (p < 0.0001). Only one of seven subjects who had previously responded to the CACh had a 15% decrease in FEV1 when the CACh was repeated at the same maximum minute ventilation achieved during EXCh (p = 0.007). In conclusion, cold air and exercise challenges do not produce the same response. Our results highlight than an explanation is the differences in the maximum-minimum ventilation achieved. [ABSTRACT FROM AUTHOR]

The article discusses about airway hyperresponsiveness as a determinant of the early asthmatic response to inhaled allergen. It informs that seasonal allergic rhinitis and asthma are initially referred incorrectly as rose catarrh less than 200 years ago. To address this problem, Charles Harrison Blackley clarified that pollen is one cause of allergic airway symptoms, studies were conducted on allergen skin testing, allergen injection therapy and passive transfer of sensitization by serum.

Objective . To evaluate the prevalence of nocturnal symptoms in a large sample of asthmatic patients, and to assess the agreement between patients' complaints and general practitioners' (GPs') reports in primary care. Design . Cross-sectional survey involved 3,526 GPs and 751 specialists (pulmonologists and allergists) and included 13,493 patients with persistent asthma. Symptoms, treatment, and social and medical data were collected in real time by the patients and their GPs. Setting . France. Results . Prevalence of nocturnal symptoms was 60%. A total of 7,989 patients with nocturnal symptoms had complete data for both patients and GPs; 3,849 (48.1%) had perfect agreement between GP and their complaints for nocturnal symptoms (agreement group; [kappa = 1]); 3,376(42.2%) declared having no symptoms during the night, but these were detected by the GP during the visit (underestimated by patients and detected by GPs); 773(9.6%) declared having nocturnal symptoms, but these were not detected by GPs. Patients with a good agreement with their GP's opinion were significantly more frequently followed-up by a specialist than other patients ( p = 0.002). Conclusions . Nocturnal symptoms appear to be underdeclared by patients. GPs should therefore systematically ask their patients about nocturnal symptoms to increase control of asthma and to adequately manage its treatment. [ABSTRACT FROM AUTHOR]

Nonspecific hyperresponsiveness to adenosine monophosphate is better related to airway inflammation than methacholine. Adenosine induces mast cells and other cells to release inflammatory mediators that produce bronchoconstriction and perhaps other inflammatory effects, such as plasma exudation, which have not been well studied. We compared the plasma exudation effect, as measured in induced sputum, between adenosine and methacholine challenge in healthy and asthmatic subjects. In a cross-over design, 42 subjects were randomly challenged with adenosine or methacholine. After recovery, induced sputum was collected on 2 separate days, 48 to 72 hours apart. In the control group, an additional challenge with saline was performed. Differential cell counts and albumin and alpha2-macroglobulin levels were determined. The sputum volume obtained was sufficient to measure proteins in only 34 subjects: 10 healthy individuals and 24 mild asthmatics. There was a significant difference between adenosine and methacholine in sputum albumin (mean differences: 68[73.4] μg/L in controls, p = 0.039 and 48.0[162.9] μg/L in asthmatics) and cell counts, but only a tendency in alpha2-macroglobulin. PC20 adenosine was better related to eosinophil counts than methacholine ( r = -0.44, p = 0.014). Albumin or alpha2-macroglubulin levels were not significantly correlated with baseline FEV 1 , PC20, or eosinophil counts. Adenosine, but not methacholine challenge, produces a mild airway plasma exudation that does not seem to be relevant to bronchoconstriction. However, this could be relevant, to some supernatant measurements after adenosine challenge. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate which factors are associated with asthma control experienced by asthma patients. In a cross-sectional study patients aged 16–60 years with mild to moderate asthma were selected. The influence of the following factors on asthma control was studied in a multivariate model: age, gender, socioeconomic status, smoking, perceived hyperresponsiveness (PHR, responding with asthma symptoms to one or more triggers), allergy (Phadiatop®), long-acting bronchodilating agents, and inhaled corticosteroids. Asthma control was measured by means of the Asthma Control Questionnaire© (ACQ) as developed by Juniper. Forced expiratory volume in 1 second (FEV 1 ) was measured by means of a portable spirometer. In this study with 311 patients, mean ACQ score was 1.39 (range 0–4.43). A stepwise backward linear regression analysis showed that low socioeconomic status (beta 0.425; p = 0.001), current smoking (beta 0.555; p [ABSTRACT FROM AUTHOR]

Background. Objective assessment of airway function is important in epidemiologic studies of asthma to facilitate comparison between studies. Airway hyperresponsiveness (AHR), peak expiratory flow (PEF) variability, and bronchodilator reversibility (BR) are widely used as markers of airway lability in such studies. Data from a survey of a population sample of adolescents and young adults (n = 609; 288 males), aged 13–23 years, were analyzed to investigate whether AHR, PEF variability, and BR can be used interchangeably as markers of asthma in an epidemiological setting. Methods. Case history, including self-reported and doctor-diagnosed asthma, smoking habits, and use of asthma medication, was obtained by interview and questionnaire. Lung function, airway responsiveness (positive test: PC 20 FEV 1 20%), BR (positive test: ΔFEV 1 [(FEV 1 max - FEV 1 min)/FEV 1 max) 100]> 10%), blood eosinophil count, and skin prick test reactivity were measured by using standard techniques. Results. The prevalence of a positive test was AHR 16.4%, PEFpos 13.3%, and BRpos 7.2%, respectively; 73.5% of the sample had three negative tests. Among the 74 participants with current self-reported asthma (12.2%), 34 subjects (46%) had more than one positive test. Using AHR as the only objective marker of asthma identified 93% of the participants with current asthma, whereas PEF and BR identified 45% and 10%, respectively. Confining the analysis to participants with only one positive test revealed that 61% of the subjects with isolated AHR had current asthma, whereas none of the subjects with isolated BRpos had asthma, and only one participant with isolated PEFpos had current asthma. Degree of histamine responsiveness was closer associated with other asthma-related factors, including self-reported asthma, use of asthma medication, and level of lung function, than PEF variability and bronchodilator responsiveness. Conclusions. Airway responsiveness to histamine, diurnal peak-flow variability, and bronchodilator reversibility cannot be used interchangeably as objective markers of asthma in epidemiologic studies. On the basis of the present findings, airway hyperresponsiveness to a nonspecific bronchoconstrictor is recommended as the objective marker of asthma-related airway lability. [ABSTRACT FROM AUTHOR]

Background. Asthma is a complex inflammatory lung disease that results from allergic and nonallergic environmental exposures in genetically susceptible individuals. The interrelationship and impact of environmental and genetic determinants on the development of asthma is still unclear. Monozygotic twins (MZT) have been considered a potentially useful population to investigate the role of genetic and environmental factors on asthma because of their identical genetic background, similar childhood environmental exposures, and expected high concordance rate for asthma. Methods. A detailed questionnaire designed to obtain demographic information, medical history/severity of asthma, and environmental exposures was distributed to 43 pairs of MZT pairs where one or both probands had a history of asthma. All twin pairs were clinically evaluated for atopy by skin testing. Asthma was assessed by questionnaire, baseline spirometry, disease severity, airway reactivity, and medication scores. Results. Based on a history of physician-diagnosed asthma, disease severity, airway reactivity, and medication scores, 22 MZT pairs were identified as concordant (C) for asthma while 21 MZT pairs were discordant (D) for asthma. Those MZT-C for asthma were on average older and more often female. Adjusted odds ratios for age and gender revealed that MZT-C for asthma had a 2.3 greater likelihood of childhood tobacco exposure and a 1.8 greater likelihood of early exposure to a pet compared to MZT-D pairs. In addition, MZT-C for asthma had a 2.4 greater likelihood of being full term vs. premature at birth. None of these odds ratios were statistically significant due to a small sample size. However, a trend for a greater likelihood of earlier environmental exposures was observed for MZT-C asthma pairs. Among MZT-D probands, a history of asthma in one proband was supported by a lower FEV 1 and higher airway reactivity, disease severity, asthma symptom, and medication scores compared to the nonasthma proband. There was significant intrapair heterogeneity among MZT-C and MZT-D probands in their positive skin test responses to specific aeroallergens. Conclusion. Cross-sectional evaluation of larger MZT populations where one or both proband has asthma with a long-term prospective follow-up may be a feasible way for identifying the impact of environmental determinants as independent risk factors for the development of asthma. [ABSTRACT FROM AUTHOR]

Background . Acute responsiveness to inhaled bronchodilators is often used to differentiate between bronchial asthma and chronic obstructive pulmonary disease (COPD). The response can be expressed in terms of a change in FEV 1 and FVC in several ways—as absolute change, change as percent of baseline value, or as percent of predicted value with different thresholds for a positive test. A comprehensive evaluation of the diagnostic value of these different methods of expressing the acute bronchodilator response has not been carried out. Methodology . Response to inhaled salbutamol was measured by spirometry in 200 asthmatics and 154 patients with COPD. The sensitivity, specificity, and positive and negative predictive values of different methods of expressing responsiveness were calculated. Receiver operative characteristic curves were obtained. Results . None of the expressions of response gave a clear-cut separation between the two diseases. A ?FEV 1 = 0.2 L gave the most satisfactory combination of sensitivity (73%) and specificity (80%) and the highest positive (82%) and negative predictive values (69%) for diagnosing asthma. These values were superior to those obtained for the ERS or the ATS criteria for reversibility (?FEV 1 %predicted = 9% and ?FEV 1 of = than 12% and 0.2 L over the baseline, respectively), which had almost similar diagnostic characteristics. This was confirmed by the area under curve of the ROC plots. Expressions of response in terms of changes in FVC were unsatisfactory in separating the two diseases. Conclusions . It was concluded that the test of acute bronchodilator responsiveness has limited diagnostic value in separating asthma and COPD. [ABSTRACT FROM AUTHOR]

Information on asthma morbidity outcomes in relation to the initial degree of severity is scarce. Objective. To determine the differences in asthma morbidity, quality of life (QOL), and lung function outcomes according to the initial severity of the illness. Method. A cohort of 235 (102 mild, 69 moderate, and 64 severe) asthma patients was followed up for 3 years. The following parameters were collected for all patients: asthma morbidity, clinical data, spirometry, and St. George's Respiratory Questionnaire (SGRQ). [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether bronchial hyperresponsiveness in adolescents with long-term asthma remission is associated with increased peak expiratory flow (PEF) variability and/or increased bronchial response to exercise (BRE). Twenty-nine adolescents with asthma remission (neither symptoms nor any medication used during the previous two years), but with persistent methacholine hyperresponsiveness (PC 20 [ABSTRACT FROM AUTHOR]

This prospective study was designed to determine whether incorporating formoterol into a standardized respiratory therapist-directed protocol for administering bronchodilators to hospitalized patients with obstructive airway disease would reduce health care resource use and provide a safety advantage. All patients admitted to Washington Hospital Center with asthma and chronic obstructive pulmonary disease (CODP) are administered bronchodilators under a standardized respiratory therapist-directed protocol. Formoterol was the primary bronchodilator for the intervention period from January through March 2002, with levalbuterol, albuterol, and ipratropium available as needed. Results for the intervention period were compared against two historical control periods. From January through March 2000, the bronchodilators in the protocol were albuterol and ipratropium, and from January through March 2001 levalbuterol, albuterol, and ipratropium were available. Health care resource use was determined by the number of bronchodilator treatments administered per admission. Costs (adjusted to 2002 dollars) for supplies, therapist time, and drugs were calculated for the three time periods. Adverse events related to bronchodilator administration were recorded in a standardized manner for all three time periods. Bronchodilator treatments per admission, respiratory therapist visits per admission, and time spent per admission, and cost per bronchodilator treatment significantly decreased in 2002. Significantly fewer adverse events related to bronchodilator treatments were reported in 2002 than 2000. The addition of formoterol to a respiratory therapist-directed protocol for administering bronchodilators reduced health care resource use and adverse events for patients with asthma and COPD. [ABSTRACT FROM AUTHOR]

A cross-sectional study was conducted in Bayamón, Puerto Rico, to identify and quantify indoor allergens, serine proteases, and bacterial endotoxin present in homes of asthmatic children. A total of 126 dust samples from houses were obtained from the entire mattress and bedside floor. Most of the patients had detectable levels of mite, cockroach, cat, and dog allergens. Mold allergens were found only in bedside floor dust samples. Mouse allergens were not detected. Forty-two percent, 36.5%, and 1.8% of the patients demonstrated exposures to sensitizing levels of mite, Bla g 1 and cat allergens, respectively. The percentage of patients exposed to high levels of allergens capable of triggering asthma symptoms was 33.3% and 26.4% for mite and Bla g 1 allergens. Only dog allergen, bacterial endotoxin, elastase, and trypsin were associated with asthma symptoms. Eighty-nine percent of the asthmatic children were exposed to endotoxin concentrations greater than 100 EU/mg dust, and more than half of the patients were exposed to high levels of serine proteases. Our study indicates that indoor concentrations of allergens traditionally associated with asthma symptoms and severity may not be applicable in tropical environments and highly ventilated households. In fact, in the study population, endotoxins, dog allergen, and serine proteases may play a dominant role in the induction of asthma symptoms. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Quality of Life (QoL) measurements are more responsive to clinically significant changes than conventional clinical measures. The aim of the study was to evaluate the relationship between asthma symptoms and QoL in asthmatic patients. METHODS: A total of 277 asthmatics subjects, divided into three groups showing different symptoms, underwent complete clinical evaluation, baseline respiratory function, and methacholine challenge test and completed an Asthma Quality of Life Questionnaire (AQLQ). RESULTS: One hundred and forty-five subjects with asthmatic crisis, chest tightness, and dyspnea (group 3) reported a significantly lower median value in single domains and all items compared to the values scored by the 97 subjects with wheezing, rhinitis, and conjunctivitis (group 2) (p<0.01). No statistical significance was found between the 35 patients of group 1 (with only cough) and group 3. CONCLUSIONS: The main advantage for the clinician is to evaluate important areas in which QoL could be improved and the possibility to correct and optimize compliance to chronic therapy. [ABSTRACT FROM AUTHOR]

A multicomponent model has been developed to explain patients' unmet expectations of medical care. The model proposes that expectations are related to patients' personal experiences with illness, perceived vulnerability to disease, transmitted knowledge, and perceived severity of disease. The objective of this cross-sectional study was to determine whether this model can be applied to patients' unrealistic expectations of treatment outcomes, specifically expecting to be cured of asthma. In total, 230 patients observed in a primary care practice in New York City were interviewed in person with open-ended questions about their expectations of asthma treatment. Responses were analyzed with qualitative techniques to generate categories of expectations. Patients had a mean age of 41 ± 11 years, 21% were white, 30% African American, 42% Latino, and 7% other groups. Major categories of expectations were generated from patients' responses and included symptom relief (expected by 52%), cure (36%), improved physical function (21%), and improved psychological well-being (15%). The category of expecting a cure was assessed with patients' responses to the following items representing components of the model: 1) resource utilization and medication requirements for asthma (representing severity of disease); 2) perceived quality of asthma care and satisfaction with care (representing past asthma experiences); 3) the Asthma Self-Efficacy Scale (representing perceived vulnerability to exacerbations); and 4) experiences of social network contacts with asthma and the Check Your Asthma IQ survey (representing transmitted knowledge). In bivariate analysis, patients who expected a cure were more likely to be Latino or Native American or Asian (p = 0.02), to have never required oral corticosteroids (p = 0.004), to be dissatisfied with the status of their asthma (p = 0.008), to know others who were limited by asthma (p = 0.03), to have w... [ABSTRACT FROM AUTHOR]

The national guidelines for the diagnosis and management of asthma published in April of 1997 emphasized patient education in asthma management. It is unclear how often patient education is included in asthma management clinics. We sought to determine how often education programs are available by surveying teaching hospitals with training programs in pulmonary and critical care medicine. Using this survey, we also determined the reason programs are not offered and whether computer resources are routinely available to utilize computer-delivered patient educational materials. We sent mail questionnaires to 163 training programs in the United States. We had a response rate of 72% (117 of 163). Of the 117 programs responding, 75 (64%) reported having a formal asthma patient education program. Most (72%) were in university teaching hospitals. A majority of respondents (84%) believed that compensation for their efforts was inadequate, and those hospitals with no formal asthma education program reported that financial cost and time requirements were the primary reasons for not having such a program. Despite the fact that many programs did not have a patient education component, 96% (72 of 75) of respondents with an educational program viewed patient education as an effective patient self-management tool. Of all programs surveyed, 85% reported they would use a high-quality computer-based asthma education program if one was available. Implementation of such a program is feasible, with 69% of programs surveyed having a personal computer in their clinic and 60% having Internet access. We conclude that most training directors believe that patient asthma education is important and effective; however, cost and time issues remain barriers to its implementation. Computer-based educational programs delivered over the Internet are feasible, could address some of these limitations, and are acceptable to most programs. [ABSTRACT FROM AUTHOR]

In the management of patients with asthma, peak expiratory flow (PEF) monitoring is used and based on the individual best PEF or the predicted PEF. Recent international guidelines have recommended the use of the best PEF rather than the predicted PEF as an index, although there is little evidence to support which index is more appropriate. Therefore, we investigated the relationship between the best PEF and the predicted PEF in 166 consecutive asthmatic patients to see which value would be the better basis for their PEF monitoring. All eligible patients had undergone treatment for their asthma for over 6 months and were asked to measure their PEF four times a day. The best PEF was defined as the maximal PEF achieved at any time from all previous measurements. The predicted PEF was calculated based on a report on the standard PEF in normal Japanese subjects. The mean best PEF was significantly higher than the mean predicted PEF (p < 0.001). There was a strong correlation between the best PEF and the predicted PEF (r = 0.77, p < 0.001). However, in 72 patients (43%) the ratio of the best PEF to the predicted PEF was over 110%, and in 20 patients (12%) the ratio was lower than 90%. The best PEF was higher than the predicted PEF in 76 patients (46%) and lower in 22 patients (13%) by more than 50 L/min. These results suggest that when the predicted PEF was used as the index, pulmonary function was either underestimated or overestimated in over half of these patients. Therefore, the best PEF may be the better index for the management of patients with asthma. [ABSTRACT FROM AUTHOR]