Asthma Events Research Articles

Evaluating the impact of an integrated computer-based decision support with person-centered analytics for the management of asthma in primary care: a randomized controlled trial.

Background Computer-based decision support has been effective in providing alerts for preventive care. Our objective was to determine whether a personalized asthma management computer-based decision support increases the quality of asthma management and reduces the rate of out-of-control episodes.Methods A cluster-randomized trial was conducted in Quebec, Canada among 81 primary care physicians and 4447 of their asthmatic patients. Patients were followed from the first visit for 3–33 months. The physician control group used the Medical Office of the 21st century (MOXXI) system, an integrated electronic health record. A custom-developed asthma decision support system was integrated within MOXXI and was activated for physicians in the intervention group.Results At the first visit, 9.8% (intervention) to 12.9% (control) of patients had out-of-control asthma, which was defined as a patient having had an emergency room visit or hospitalization for respiratory-related problems and/or more than 250 doses of fast-acting β-agonist (FABA) dispensed in the past 3 months. By the end of the trial, there was a significant increase in the ratio of doses of inhaled corticosteroid use to fast-acting β-agonist (0.93 vs. 0.69: difference: 0.27; 95% CI: 0.02–0.51; P = 0.03) in the intervention group. The overall out-of-control asthma rate was 54.7 (control) and 46.2 (intervention) per 100 patients per year (100 PY), a non-significant rate difference of −8.7 (95% CI: −24.7, 7.3; P = 0.29). The intervention’s effect was greater for patients with out-of-control asthma at the beginning of the study, a group who accounted for 44.7% of the 5597 out-of-control asthma events during follow-up, as there was a reduction in the event rate of −28.4 per 100 PY (95% CI: −55.6, −1.2; P = 0.04) compared to patients with in-control asthma at the beginning of the study (−0.08 [95% CI: −10.3, 8.6; P = 0.86]).Discussion This study evaluated the effectiveness of a novel computer-assisted ADS system that facilitates systematic monitoring of asthma control status, follow-up of patients with out of control asthma, and evidence-based, patient-specific treatment recommendations. We found that physicians were more likely to use ADS for out-of-control patients, that in the majority of these patients, they were advised to add an inhaled corticosteroid or a leukotriene inhibitor to the patient s treatment regimen, and the intervention significantly increased the mean ratio of inhaled corticosteroids to FABA during follow-up. It also reduced the rate of out-of-control episodes during follow up among patients whose asthma was out-of-control at the time of study entry. Future research should assess whether coupling patient-specific treatment recommendations, automated follow-up, and home care with comparative feedback on quality and outcomes of care can improve guideline adoption and care outcomes.Conclusions A primary care-personalized asthma management system reduced the rate of out-of-control asthma episodes among patients whose asthma was poorly controlled at the study’s onset.Trial Registration Clinicaltrials.gov Identifier: NCT00170248 http://clinicaltrials.gov/ct2/show/NCT00170248?term=Asthma&spons=McGill+University&state1=NA%3ACA%3AQC&rank=2

Asthma incidence, remission, relapse and persistence: a population-based study in southern Taiwan.

BackgroundIn western countries, late-onset asthmatics are more severe than early-onset asthmatics in clinic-based studies. However, whether asthma occurrence rates were higher in late ages than in younger ages was inconclusive. This information is essentially lacking in Asian population.MethodsThe participants were schoolchildren’s parents recruited from 94 elementary and middle schools in 2004. A cross-sectional self-administered questionnaire was sent through the children to their parents to survey their respiratory health. We investigated typical asthma symptoms occurring at different ages and subsequent remission or relapse after the first asthma event. Person-years of the participants from birth to the time of survey were used as the denominator.ResultsAmong the 25,377 participants consisting of 949,807 total person-years, 860 reported ever having asthma. Highest incidences occurred at ages 0–12 and 36–40 years. The incidence of asthma was higher in males before puberty, and higher in females after puberty, with overall incidences 1.00 and 0.77 per 1000 person-years for females and males, respectively. Participants with late-onset asthma (onset age >12 years) comprised a large portion of adult current asthmatics. More than 52% of persistence or relapse was observed in early-onset asthma (onset age ≤12 years). The younger birth cohort had a more prominent later peak of asthma incidence than the older one.ConclusionsIn Asian population, asthma occurrence showed a U-shape age distribution with a prominent second peak in the thirties. A high proportion of early-onset asthma relapsed and most of late-onset asthma persisted or relapsed in adulthood.

Ambient Ozone and Children's Acute Asthma in New York City: a Comparison of Time-Series and Case-Crossover Analyses with Spatially-Resolved Air Pollution Metrics

Ambient Ozone and Children's Acute Asthma in New York City: a Comparison of Time-Series and Case-Crossover Analyses with Spatially-Resolved Air Pollution MetricsAbstract Number:2277 Jiang Zhou*, Jessie Shmool, and Jane Clougherty Jiang Zhou* University of Pittsburgh, United States, E-mail Address: [email protected] Search for more papers by this author , Jessie Shmool University of Pittsburgh, United States, E-mail Address: [email protected] Search for more papers by this author , and Jane Clougherty University of Pittsburgh, United States, E-mail Address: [email protected] Search for more papers by this author AbstractBackground Daily changes in ozone have been associated with childhood asthma emergency department (ED) visits and hospitalizations. Prior studies, however, have lacked high- resolution ozone exposure data, relying instead on regional concentration estimates from regulatory monitors, leading to exposure misclassification. Further, few studies compare results in time-series and case-crossover models.Objectives We aim to examine associations between highly spatially- and temporally-resolved ozone exposure estimates and ED visits and hospitalizations for childhood asthma, by combining New York City Community Air Survey (NYCCAS) ozone surface data with daily ozone trends from local EPA Air Quality System (AQS) monitors, to improve spatio-temporal exposure assignment and epidemiological analyses.Methods We compared time-series and case-crossover models for acute effects of ambient ozone using asthma admissions data – ED visits (n = 35,907) and hospitalizations (n = 8,009) for children aged 5 to 17 – and ambient ozone data for May through September from 2005 to 2011. Time-series models were adjusted for temporal trends, temperature, and day of the week. Conditional logistic regression models were used in case-crossover analysis. Excess risks were estimated for interquartile range (IQR) increases in ozone exposures.Results Similar acute effects of ozone on asthma events were observed in both time-series and case-crossover analyses, with similar lag structures. Overall, ozone was positively associated with asthma ED visits in both sexes, for one to six lag days, peaking at lag day 3 (excess risk = 9%; 95% CI: 6.4%, 11.8%). Among asthma hospitalizations, we observed significant effects of ozone for girls, but not boys.Conclusions Ambient ozone was significantly associated with asthma ED visits and hospitalizations. Models will be developed to include spatially-adjusted ozone level in the case-crossover model to capture spatial variation in daily ozone exposures.

Associations between ozone, PM2.5, and four pollen types on emergency department pediatric asthma events during the warm season in New Jersey: A case-crossover study

BackgroundAsthma is one of the most common chronic diseases among school-aged children in the United States. Environmental respiratory irritants exacerbate asthma among children. Understanding the impact of a variety of known and biologically plausible environmental irritants and triggers among children in New Jersey – ozone, fine particulate matter (PM2.5), tree pollen, weed pollen, grass pollen and ragweed – would allow for informed public health interventions. MethodsTime-stratified case-crossover design was used to study the transient impact of ozone, PM2.5 and pollen on the acute onset of pediatric asthma. Daily emergency department visits were obtained for children aged 3–17 years with a primary diagnosis of asthma during the warm season (April through September), 2004–2007 (inclusive). Bi-directional control sampling was used to select two control periods for each case for a total of 65,562 inclusion days. Since the period of exposure prior to emergency department visit may be the most clinically relevant, lag exposures were investigated (same day (lag0), 1, 2, 3, 4, and 5 as well as 3-day and 5-day moving averages). Multivariable conditional logistic regression controlling for holiday, school-in-session indicator, and 3-day moving average for temperature and relative humidity was used to examine the associations. Odds ratios are based on interquartile range (IQR) increases or 10 unit increases when IQR ranges were narrow. Single-pollutant models as well as multipollutant models were examined. Stratification on gender, race, ethnicity and socioeconomic status was explored. ResultsThe associations with ozone and PM2.5 were strongest on the same day (lag0) of the emergency department visit (RRIQR=1.05, 95% CI 1.04–1.06) and (RRIQR=1.03, 95% CI 1.02–1.04), respectively, with a decreasing lag effect. Tree and weed pollen were associated with pediatric ED visits; the largest magnitudes of association was with the 5-day average (RRIQR=1.23, 95% CI 1.21–1.25) and (RR10=1.13, 95% CI 1.12–1.14), respectively. Grass pollen was only minimally associated with the outcome while ragweed had a negative association. ConclusionsThe ambient air pollutant ozone is associated with increases in pediatric emergency department asthma visits during the warm weather season. The different pollen types showed different associations with the outcome. High levels of tree pollen appear to be an important risk factor in asthma exacerbations.

Lung remodeling in a mouse model of asthma involves a balance between TGF-β1 and BMP-7.

A key event in chronic allergic asthma is the TGF-β-induced activation of fibroblasts into α-SMA-positive myofibroblasts which synthesize type-I collagen. In the present study we investigated the effect of the anti-fibrotic molecule BMP-7 in asthma. Balb/c mice were immunized i.p. with ovalbumin in alum and challenged every 2 days with ovalbumin aerosol (two or six challenges for acute and chronic protocols, respectively). The lung was evaluated for: α-SMA and type-I collagen by immunohistochemistry; BMP-7 and TGF- β1 gene expression by qRT-PCR; type-I collagen and Smads 2 and 3 by immunoblotting; mucus by PSA staining. Type-I collagen around bronchi, α-SMA, mucus secretion, TGF- β1 and BMP-7 gene expression were all increased in asthma. The TGF- β1/BMP-7 ratio was higher in the chronic group and correlated with higher levels of collagen. Fibroblasts isolated from asthmatic and healthy lungs produced type-I collagen upon stimulation with TGF- β1 via phosphorylation of Smad-2, Smad-3. Pre-treatment of the fibroblasts with BMP-7 reduced collagen production and Smads phosphorylation. Intranasal treatment of asthmatic mice with recombinant BMP-7 during the immunization protocol reduced lung inflammation and type I collagen deposition. These results suggest a protective role for BMP-7 in lung allergic inflammation, opposing the pro-fibrotic effects of TGF- β1.

A pseudo-penalized quasi-likelihood approach to the spatial misalignment problem with non-normal data.

Spatially referenced datasets arising from multiple sources are routinely combined to assess relationships among various outcomes and covariates. The geographical units associated with the data, such as the geographical coordinates or areal-level administrative units, are often spatially misaligned, that is, observed at different locations or aggregated over different geographical units. As a result, the covariate is often predicted at the locations where the response is observed. The method used to align disparate datasets must be accounted for when subsequently modeling the aligned data. Here we consider the case where kriging is used to align datasets in point-to-point and point-to-areal misalignment problems when the response variable is non-normally distributed. If the relationship is modeled using generalized linear models, the additional uncertainty induced from using the kriging mean as a covariate introduces a Berkson error structure. In this article, we develop a pseudo-penalized quasi-likelihood algorithm to account for the additional uncertainty when estimating regression parameters and associated measures of uncertainty. The method is applied to a point-to-point example assessing the relationship between low-birth weights and PM2.5 levels after the onset of the largest wildfire in Florida history, the Bugaboo scrub fire. A point-to-areal misalignment problem is presented where the relationship between asthma events in Florida's counties and PM2.5 levels after the onset of the fire is assessed. Finally, the method is evaluated using a simulation study. Our results indicate the method performs well in terms of coverage for 95% confidence intervals and naive methods that ignore the additional uncertainty tend to underestimate the variability associated with parameter estimates. The underestimation is most profound in Poisson regression models.

Link between vitamin D and airway remodeling.

In the last decade, many epidemiologic studies have investigated the link between vitamin D deficiency and asthma. Most studies have shown that vitamin D deficiency increases the risk of asthma and allergies. Low levels of vitamin D have been associated with asthma severity and loss of control, together with recurrent exacerbations. Remodeling is an early event in asthma described as a consequence of production of mediators and growth factors by inflammatory and resident bronchial cells. Consequently, lung function is altered, with a decrease in forced expiratory volume in one second and exacerbated airway hyperresponsiveness. Subepithelial fibrosis and airway smooth muscle cell hypertrophy are typical features of structural changes in the airways. In animal models, vitamin D deficiency enhances inflammation and bronchial anomalies. In severe asthma of childhood, major remodeling is observed in patients with low vitamin D levels. Conversely, the antifibrotic and antiproliferative effects of vitamin D in smooth muscle cells have been described in several experiments. In this review, we briefly summarize the current knowledge regarding the relationship between vitamin D and asthma, and focus on its effect on airway remodeling and its potential therapeutic impact for asthma.

Fixed airflow obstruction in asthma: a descriptive study of patient profiles and effect on treatment responses

Background: The role of fixed airflow obstruction (FAO) in asthma is unclear. Objective: To assess the relationship between FAO and clinical features of asthma and the effect of FAO on treatment response. Methods: Post hoc descriptive analysis of data stratified by FAO category (screening post-albuterol FEV1/FVC <lower limit of normal [LLN] [FAO+] or ≥LLN [FAO−]) from two 12-week, randomized, placebo-controlled studies of budesonide/formoterol or the monocomponents in mild−moderate (study I; aged ≥6 years; NCT00651651; placebo run-in) or moderate−severe (study II; ≥12 years; NCT00652002; budesonide run-in) asthma patients. Results: At baseline, FAO+ versus FAO− patients were more likely male and had longer asthma duration and worse pulmonary function. During the treatment period, lung function and asthma control measures with placebo were generally worse in FAO+ versus FAO− patients. Budesonide was effective on most end points in both FAO+ and FAO− patients. In contrast to FAO− patients, FAO+ patients were unresponsive to formoterol monotherapy in both study populations. Consistently greater improvements in most end points (including worsening of asthma as predefined by specific lung function parameters or clinical symptoms) were observed moving from formoterol to budesonide to budesonide/formoterol in both FAO+ and FAO− patients, with generally greater than additive effects on lung function with budesonide/formoterol in FAO+ patients. Conclusions: FAO+ patients tended to be more impaired and at greater risk for an asthma event versus FAO− patients. While FAO+ patients were non-responsive to formoterol monotherapy, they retained responsiveness to budesonide and had the greatest lung function and control responses to budesonide/formoterol that were similar to or greater than responses of FAO− patients.

Asthma coalition effects on vulnerable sub groups of children: the most frequent users of health care and the youngest

Objective: To examine the impact of Allies Against Asthma, community-based coalitions working to improve asthma outcomes, on vulnerable children: those with the most urgent health care use and those of youngest age. Methods: Allies zip codes were matched with comparison communities on demographic factors. Five years of Medicaid data (n = 26,836) for significant health care events: hospitalizations, ED and urgent care facility visits, were analyzed. Longitudinal analyses using generalized estimating equations and proportional hazards models compared Allies and comparison group children. Results: In the two start-up years of Allies, odds of having a significant event were greater for Allies children than for comparison children (p < 0.05). During the third and fourth years when Allies activities were fully implemented, for frequent health care users at baseline, odds of an asthma event were the same for both Allies and comparison children, yet in the less frequent users, odds of an event were lower in Allies children (p < 0.0001). In the initial year of Allies efforts, among the youngest, the Allies children had greater odds than comparison children of an event (p < 0.01), but by the fourth year the Allies group had lower odds (p = 0.02) of an event. Hazard ratios over all years of the study for the youngest Allies children and most frequent baseline users of urgent care were lower than for comparison children (p = 0.01 and p = 0.0004). Conclusion: Mobilizing a coalition of diverse stakeholders focused on policy and system change generated community-wide reductions over the long-term in health care use for vulnerable children.

The Genetic Variants of Thymic Stromal Lymphopoietin Protein in Children with Asthma and Allergic Rhinitis

Background: Thymic stromal lymphopoietin (TSLP) is expressed by airway epithelial cells and plays a key role in immunological events in asthma. Data on the genetic variants of TSLP and its association with asthma and allergic rhinitis are scarce. We aimed to investigate the effects of the genetic variants of TSLP in children with asthma and allergic rhinitis. Methods: The genetic variants of the TSLP gene were determined by sequencing 25 asthmatic and 25 healthy children. In an association study, a population of 506 asthmatics and 157 healthy controls was screened for the following single-nucleotide polymorphisms (SNPs): rs3806933 and rs2289276 in the promoter region; rs11466741, rs11466742, and rs2289278 in intron 2; rs10073816, rs11466749, and rs11466750 in exon 4, and rs11466754 in 3′-UTR. Results: In Multifactor Dimensionality Reduction analysis, presence of the rs11466749 AA genotype with atopy was significantly associated with a diagnosis of asthma (testing set accuracy: 0.720 and cross validation: 9/10). Two functional SNPs showed a gender-specific association with allergy, i.e. the rs3806933 CC genotype with asthma in boys (p = 0.032, nonsignificant after multiple testing) and the rs2289276 CC genotype with higher eosinophil numbers in asthmatic girls (p = 0.003). The presence of allergic rhinitis in asthmatic children strengthened the association of the rs11466749 GG genotype with asthma (p = 0.001), and rs2289276 was significantly associated with lower FEV₁ levels in asthmatics without allergic rhinitis (p = 0.003). Conclusion: Variants in the gene encoding the TSLP protein may have differential effects on asthma phenotypes depending on gender, atopy, and the presence of allergic rhinitis.

Asthma control in the workplace

Workplace exposures may result, in susceptible workers, in the development of occupational asthma from sensitising or toxic/irritant exposure, or in the worsening of a pre-existing asthmatic condition, so-called “work-exacerbated asthma” [1–3]. Occupational asthma is a relatively common condition, although it is often unrecognised [1, 4]. Exposure to the sensitising agents can lead to permanent airway changes, so that even when stopped, the majority of workers will still experience persistent asthma symptoms and show residual airway hyperresponsiveness [2–5]. Early cessation from exposure to the offending agent, however, results in a better prognosis, while persistent exposure can lead to more severe asthma and more frequent acute asthma events [5, 6]. It has become evident from recent studies of work-exacerbated asthma that exposure to “asthmagens” and irritants at the workplace can lead to troublesome symptoms and trigger exacerbations of asthma [1, 6, 7]. As for non-work-related asthma, poor asthma control can result from common environmental exposures, such as allergens or pollutants in susceptible subjects, or from insufficient controller therapy or non-adherence to it. Such poor “baseline” airway control may render the worker more susceptible to the effects of various dusts, aerosols and other contaminants at work, and predispose to asthma exacerbations [1, 8, 9]. However, the contribution of various exposures at work to asthma control and exacerbations remains to be better documented. The European Community Respiratory Health Survey (ECRHS) I and II have been a rather useful source of information on asthma and these data are certainly still currently relevant. In this issue of the European Respiratory Journal , Le Moual et al . [10] looked at the relationship between occupational exposures and asthma control, as defined …

Prevention of Atrial Fibrillation with Ultra-Low Dose Landiolol after Off-Pump Coronary Artery Bypass Grafting

Postoperative atrial fibrillation (AF) is a common complication of cardiac surgery that is associated with an increased incidence of other complications. The goal of this prospective randomized study was to evaluate the effect of ultra-low dose landiolol hydrochloride for prevention of AF after off-pump coronary artery bypass grafting (CABG). The subjects were 47 patients who underwent isolated CABG and were randomly divided into those who received landiolol from ICU admission until the beginning of oral drug intake (Group L) and those administered diltiazem hydrochloride over the same period (Group D). The incidence of AF within one week after surgery was examined as the primary endpoint. Heart rate, blood pressure, cardiac output, and other hemodynamic parameters were used as secondary endpoints. The rates of adverse events were also recorded. The incidences of AF in the first postoperative week were 4.8% and 27% in Groups L and D, respectively (p = 0.046). There were no differences in hemodynamic parameters between the Groups. In multivariate analysis, no factor emerged as a significant risk factor for postoperative AF. Two patients had adverse events of asthma and hypotension, respectively, in Group L. Ultra-low dose landiolol is effective for preventing AF after CABG without worsening hemodynamics.

Loss of asthma control after cessation of omalizumab treatment: real life data

IntroductionMany clinical and observational studies have demonstrated effectiveness of omalizumab (OMA) in the treatment of severe asthma, but the optimal duration of the therapy remains unknown.AimThe article presents the authors’ clinical experience on OMA cessation in routine practice.Material and methodsDue to new reimbursement criteria, OMA therapy has been interrupted in 11 subjects (6 women/5 men). The mean age of patients was 50.73 ±14.16 years, the mean time of severe asthma duration was 13.54 ±6.05 years. All of them had an excellent/good response to OMA. The duration of OMA therapy was 67.73 ±11.64 months.ResultsNine out of 11 patients had severe asthma exacerbation within the first 5 months after the OMA withdrawal. The mean time to the first severe exacerbation was 7.56 ±2.67 weeks. Between the time of OMA cessation and the time of reassessment, the mean score of Asthma Control Questionnaire increased from 2.58 ±0.71 to 3.63 ±1.26 points and the mean score of Asthma Quality of Life Questionnaire decreased from 4.3 ±1.91 to 3.18 ±1.17 points. The mean oral corticosteroids (OCS) dose increased from 4.61 ±3.0 mg/day to 33.33 ±13.12 mg/day. The number of exacerbations within the last 12 months increased from 1.6 ±0.67 to 5.2 ±1.4, and the number of hospitalizations or emergency room (ER) attendence increased from 0.11 ±0.31 to 1.56 ±1.26.ConclusionsThese data indicate that the withdrawal of OMA therapy after the successful long-term therapy may cause severe asthma exacerbations. Therefore, the decision regarding cessation of OMA treatment should be undertaken individually after careful weighing benefits and risks, especially in patients with a long history of severe asthma, treated with high doses of OCS before OMA introduction, near-fatal asthma events and/or aggravation of asthma during previous episodes of interruptions in OMA treatment.

Geospatial relationships of air pollution and acute asthma events across the Detroit–Windsor international border: Study design and preliminary results

The Geospatial Determinants of Health Outcomes Consortium (GeoDHOC) study investigated ambient air quality across the international border between Detroit, Michigan, USA and Windsor, Ontario, Canada and its association with acute asthma events in 5- to 89-year-old residents of these cities. NO2, SO2, and volatile organic compounds (VOCs) were measured at 100 sites, and particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) at 50 sites during two 2-week sampling periods in 2008 and 2009. Acute asthma event rates across neighborhoods in each city were calculated using emergency room visits and hospitalizations and standardized to the overall age and gender distribution of the population in the two cities combined. Results demonstrate that intra-urban air quality variations are related to adverse respiratory events in both cities. Annual 2008 asthma rates exhibited statistically significant positive correlations with total VOCs and total benzene, toluene, ethylbenzene and xylene (BTEX) at 5-digit zip code scale spatial resolution in Detroit. In Windsor, NO2, VOCs, and PM10 concentrations correlated positively with 2008 asthma rates at a similar 3-digit postal forward sortation area scale. The study is limited by its coarse temporal resolution (comparing relatively short term air quality measurements to annual asthma health data) and interpretation of findings is complicated by contrasts in population demographics and health-care delivery systems in Detroit and Windsor.

Anti-inflammatory Treatment of Atopic Asthma Guided by Exhaled Nitric Oxide: A Randomized, Controlled Trial

Atopic asthma is characterized by Th2 cytokine-driven inflammation of the airway mucosa, which is signaled by the fraction of exhaled nitric oxide (FENO). We tested whether an FENO-guided anti-inflammatory treatment algorithm could improve asthma-related quality of life and asthma symptom control, and reduce exacerbations in atopic asthmatics within primary care. Altogether, 187 patients with asthma and who were nonsmokers (age range, 18-64 years) with perennial allergy and who were on regular inhaled corticosteroid treatment were recruited at 17 primary health care centers, randomly assigned to 2 groups and followed up for 1 year. For the controls (n = 88), FENO measurement was blinded to both operator and patient, and anti-inflammatory treatment was adjusted according to usual care. In the active group (n = 93), treatment was adjusted according to FENO. Questionnaires on asthma-related quality of life (Mini Asthma Quality of Life Questionnaire) and asthma control (Asthma Control Questionnaire) were completed, and asthma events were noted. The Asthma Control Questionnaire score change over 1 year improved significantly more in the FENO-guided group (-0.17 [interquartile range {IQR}, -0.67 to 0.17] vs 0 [-0.33 to 0.50]; P = .045), whereas the Mini Asthma Quality of Life Questionnaire score did not (0.23 [IQR, 0.07-0.73] vs 0.07 [IQR, -0.20 to 0.80]; P = .197). The change in Asthma Control Questionnaire was clinically important in subpopulations with poor control at baseline (P = .03). Furthermore, the exacerbation rate (exacerbations/patient/y) was reduced by almost 50% in the FENO-guided group (0.22 [CI, 0.14-0.34] vs 0.41 [CI, 0.29-0.58]; P = .024). Mean overall inhaled corticosteroid use was similar in both groups (P = .95). Use of FENO to guide anti-inflammatory treatment within primary care significantly reduced the exacerbation rate and improved asthma symptom control without increasing overall inhaled corticosteroid use.

A simulation model of building intervention impacts on indoor environmental quality, pediatric asthma, and costs

Although indoor environmental conditions can affect pediatric asthmatic patients, few studies have characterized the effect of building interventions on asthma-related outcomes. Simulation models can evaluate such complex systems but have not been applied in this context. We sought to evaluate the impact of building interventions on indoor environmental quality and pediatric asthma health care use, and to conduct cost comparisons between intervention and health care costs and energy savings. We applied our previously developed discrete event simulation model (DEM) to simulate the effect of environmental factors, medication compliance, seasonality, and medical history on (1) pollutant concentrations indoors and (2) asthma outcomes in low-income multifamily housing. We estimated health care use and costs at baseline and subsequent to interventions, and then compared health care costs with energy savings and intervention costs. Interventions, such as integrated pest management and repairing kitchen exhaust fans, led to 7% to 12% reductions in serious asthma events with 1- to 3-year payback periods. Weatherization efforts targeted solely toward tightening a building envelope led to 20% more serious asthma events, but bundling with repairing kitchen exhaust fans and eliminating indoor sources (eg, gas stoves or smokers) mitigated this effect. Our pediatric asthma model provides a tool to prioritize individual and bundled building interventions based on their effects on health and costs, highlighting the tradeoffs between weatherization, indoor air quality, and health. Our work bridges the gap between clinical and environmental health sciences by increasing physicians' understanding of the effect that home environmental changes can have on their patients' asthma.

Exhaled nitric oxide levels and blood eosinophil counts independently associate with wheeze and asthma events in National Health and Nutrition Examination Survey subjects

Fraction of exhaled nitric oxide (Feno) and blood eosinophil count (B-Eos) values, markers of local and systemic eosinophilic inflammation, respectively, are increased in asthmatic patients. Little is known about the relation of these markers to reported wheeze and asthma events in a random population sample. We sought to determine the individual and independent values of B-Eos and Feno in relation to wheeze, asthma diagnosis, and asthma events in a cross-sectional study. Feno and B-Eos values were measured in 12,408 subjects aged 6 to 80 years from the National Health and Nutrition Examination Survey 2007-2008 and 2009-2010. Current wheeze and asthma diagnosis, as well as asthma attacks and asthma-related emergency department (ED) visits within the last 12 months, were assessed by means of questionnaires. Intermediate or high Feno values and intermediate or high B-Eos values were independently associated with having asthma, wheeze, and asthma attacks. However, only intermediate and high B-Eos values were independently associated with asthma-related ED visits. High Feno (≥ 50 ppb) and B-Eos (≥ 500 cells/mm(3)) values rendered an adjusted odds ratio of 4.5 of having wheeze, 5.1 of having asthma, 5.4 for asthma attacks, and 2.9 for asthma-related ED visits compared with normal Feno (<25 ppb) and B-Eos (<300 cells/mm(3)) values. Exhaled nitric oxide and B-Eos values offered independent information in relation to the prevalence of wheeze, asthma diagnosis, and asthma events in this random population sample. The clinical importance of these findings in asthmatic patients with regard to phenotyping and individualized treatment, considering both local and systemic eosinophilic inflammation, needs to be determined.

Chronic burden of near-roadway traffic pollution in 10 European cities (APHEKOM network)

Recent epidemiological research suggests that near road traffic-related pollution may cause chronic disease, as well as exacerbation of related pathologies, implying that the entire "chronic disease progression" should be attributed to air pollution, no matter what the proximate cause was. We estimated the burden of childhood asthma attributable to air pollution in 10 European cities by calculating the number of cases of 1) asthma caused by near road traffic-related pollution, and 2) acute asthma events related to urban air pollution levels. We then expanded our approach to include coronary heart diseases in adults. Derivation of attributable cases required combining concentration-response function between exposures and the respective health outcome of interest (obtained from published literature), an estimate of the distribution of selected exposures in the target population, and information about the frequency of the assessed morbidities. Exposure to roads with high vehicle traffic, a proxy for near road traffic-related pollution, accounted for 14% of all asthma cases. When a causal relationship between near road traffic-related pollution and asthma is assumed, 15% of all episodes of asthma symptoms were attributable to air pollution. Without this assumption, only 2% of asthma symptoms were attributable to air pollution. Similar patterns were found for coronary heart diseases in older adults. Pollutants along busy roads are responsible for a large and preventable share of chronic disease and related acute exacerbations in European urban areas.

Thunderstorm asthma: an overview of the evidence base and implications for public health advice

Thunderstorm asthma is a term used to describe an observed increase in acute bronchospasm cases following the occurrence of thunderstorms in the local vicinity. The roles of accompanying meteorological features and aeroallergens, such as pollen grains and fungal spores, have been studied in an effort to explain why thunderstorm asthma does not accompany all thunderstorms. Despite published evidence being limited and highly variable in quality due to thunderstorm asthma being a rare event, this article reviews this evidence in relation to the role of aeroallergens, meteorological features and the impact of thunderstorm asthma on health services. This review has found that several thunderstorm asthma events have had significant impacts on individuals' health and health services with a range of different aeroallergens identified. This review also makes recommendations for future public health advice relating to thunderstorm asthma on the basis of this identified evidence.

Association Between Consistent Omalizumab Treatment and Asthma Control

Omalizumab is indicated for patients with moderate-to-severe allergic asthma with inadequately controlled symptoms. We evaluated the association between consistent omalizumab treatment and asthma control. Health insurance claims from the MarketScan database (2002Q1-2011Q2) were analyzed. Asthmatic patients with ≥12 months of continuous insurance coverage after the first omalizumab claim (index date) after 6 months of continuous omalizumab use were included. A 12-month landmark period was used to assess treatment consistency, defined as uninterrupted treatment without a gap of ≥28 days in omalizumab use. The effect of consistent omalizumab treatment on asthma control between months 13 and 24 was evaluated. Multivariate time-varying Cox regressions were also conducted to assess the adjusted effect of treatment interruption on asthma control from month 1 to month 24. A total of 3044 patients (mean age, 48.5 years; female, 62%) formed the study population. Patients consistent with omalizumab treatment at 12 months (39% of patients) were less likely to have an uncontrolled asthma event during months 13 to 24 with only 49% of patients experiencing one event compared with 54% in the non consistent subgroup (P = .02). In addition, consistent omalizumab treatment at 12 months was associated with a 51% reduction in the mean number of asthma-related emergency department (ED) visits per patient and a 28% reduction in asthma-related hospitalizations. Multivariate analyses corroborated these findings (hazard ratio for consistent vs non-consistent: risk of short-acting β2-agonists prescription, oral corticosteroids prescription, ED visit, or hospitalization, 0.76; 95% CI, 0.69-0.83]). This analysis showed that consistent omalizumab treatment was associated with significant reductions in ED visits and hospitalizations.