Proportion Of Asthma Patients Research Articles

The value of combined detection of specific immunoglobulin E, interleukin-6 and regulatory T cells in predicting the risk of postoperative recurrence in patients with eosinophilic chronic rhinosinusitis and nasal polyps.

To investigate the predictive value of specific immunoglobulin E (sIgE), interleukin-6 (IL-6) and regulatory T cells (Treg) on the risk of postoperative recurrence in patients with eosinophilic Chronic rhinosinusitis with nasal polyps (EcRswNP). A total of 198 patients with EcRswNP collected to our Hospital from January 2019 to December 2021 were selected as the research subjects. All patients underwent functional endoscopic sinus surgery. The patients were selected to recurrence group (RG, n = 48) and nonrecurrence group (NRG, n = 150) on the basis of the recurrence after 1 year of follow-up. The related factors of postoperative recurrence of EcRswNP were analyzed. The ROC was used to analyze the dangerous of sIgE, IL-6 and Treg in predicting postoperative recurrence of EcRswNP patients. The proportion of asthma patients, nasal congestion VAS score, and peripheral blood Eos% content in the RG exceeded that in the NRG, and the Organization Neu % and peripheral blood Neu% levels were less than those in the NRGp (P all < 0.05). The serum sIgE and serum IL6 in the RG were higher than those in the NRG, while the level of peripheral blood Treg was lower than that in the NRG (P < 0.05). Logistic regression analysis showed that high levels of serum sIgE, serum IL-6 and low Treg levels were risk factors for postoperative recurrence (P < 0.05). ROC showed that the AUC of peripheral blood sIgE level, IL-6 and Treg levels alone in predicting the dangerous of postoperative recurrence in patients with EcRswNP were 0.786, 0.707 and 0.636, respectively (all P < 0.05); The AUC of combined prediction of peripheral blood sIgE, IL-6 and Treg levels for postoperative recurrence dangerous in patients with EcRswNP was 0.973, indicating that the efficacy of jointed prediction was exceed than that of single prediction (P < 0.05). The high levels of sIgE, IL6 and low Treg levels in patients with EcRswNP before operation will increase the risk of postoperative recurrence, which is a risk factor affecting postoperative recurrence, and the three indicators have good predictive value for predicting postoperative recurrence in patients with EcRswNP, and the combination of the three indicators has better value in predicting postoperative recurrence.

Short-Acting Beta2-Agonist Use in Asthma in Korea: A 10-Year Population-Based Study.

Short-acting β2-agonist (SABA) use is known to be lower in Korean patients with asthma than in those from other countries, while the rate of asthma exacerbations in Korea is higher than in other countries. Thus, an epidemiologic study on SABA use and the relationship between SABA overuse and treatment outcomes in asthma is needed in Korea. We performed a cross-sectional study using the National Health Insurance Service-National Sample Cohort 2002–2012 database. We evaluated the trend of annual SABA use and overuse (prescription of 3 or more SABA canisters/year) and the impact of SABA overuse on mortality. During the study period, the proportion of asthmatic patients who used SABA was approximately 8%–11%, with no significant change in trend. The mean annual SABA use in asthmatic patients was 0.15–0.22 canisters/patient/year and 1.93–2.05 canisters/patient/year in those who used SABA in 12 months. SABA overuse was observed in about 2%–4% of asthmatic patients during the study period. SABA overuse generally tended to increase as the age of patients increased, with triple peaks in the late 20s (3.3%), late 40s (3.1%), and late 70s (3.6%). SABA overuse was associated with mortality (adjusted odds ratio, 1.72; 95% confidence interval, 1.61–1.84). The rate of SABA use was very low in Korean asthmatic patients between 2002–2012. SABA overuse was found in 2%–4% of patients in Korea. SABA overuse was associated with an increased risk of mortality.

PRS6 QUANTIFYING THE DEGREE OF OVERLAP BETWEEN ALLERGIC AND EOSINOPHILIC SUBTYPES IN PATIENTS WITH MODERATE-TO-SEVERE ASTHMA

Asthma is increasingly recognized as a highly heterogeneous disease, with various asthma subtypes proposed, such as allergic or eosinophilic. It is unclear what proportion of asthma patients have overlapping allergic and eosinophilic subtypes. Our study aimed to characterize this proportion in the moderate-to-severe asthma population. Two post-hoc analyses of adult (≥18 years) asthma populations were conducted. The first analysis was conducted in a study population not selected for any subtype (non-subtype, N=1044), and the second analysis was conducted in a population selected for allergic asthma (N=1546). The percentage of overlapping/non-overlapping asthma subtypes in each study population was assessed using the following definitions: allergic asthma - a positive skin test or in vitro reactivity to an aeroallergen; and eosinophilic asthma - a blood eosinophil count ≥300 cells/μL. Baseline characteristics for the subtypes were also summarized. In the non-subtype selected population, 78.0% had allergic asthma and 39.3% had eosinophilic asthma. Among patients with allergic asthma, only 39.5% also had eosinophilic asthma, while 76.0% of patients with eosinophilic asthma also had allergic asthma. In the population selected for allergic asthma, 40.2% had eosinophilic asthma. Baseline demographics were similar between allergic and eosinophilic subtypes with respect to age, sex, smoking status, body mass index, and exacerbation history. Total IgE levels were similar between allergic and eosinophilic asthma. Predictably, eosinophil levels were higher in the eosinophilic asthma subtype compared with the allergic asthma subtype. In these large post-hoc analyses, allergic asthma was more prevalent than eosinophilic asthma. Although an overlap was observed between subtypes, a minority of patients with allergic asthma had concomitant eosinophilic asthma. The consistency of findings across populations provided robustness to the overlaps identified. This study quantified the degree of overlap between subtypes and may help payors to better understand patient populations and assist in formulary development.

Causes of variability in latent phenotypes of childhood wheeze

BackgroundLatent class analysis (LCA) has been used extensively to identify (latent) phenotypes of childhood wheezing. However, the number and trajectory of discovered phenotypes differed substantially between studies.ObjectiveWe sought to investigate sources of variability affecting the classification of phenotypes, identify key time points for data collection to understand wheeze heterogeneity, and ascertain the association of childhood wheeze phenotypes with asthma and lung function in adulthood.MethodsWe used LCA to derive wheeze phenotypes among 3167 participants in the ALSPAC cohort who had complete information on current wheeze recorded at 14 time points from birth to age 16½ years. We examined the effects of sample size and data collection age and intervals on the results and identified time points. We examined the associations of derived phenotypes with asthma and lung function at age 23 to 24 years.ResultsA relatively large sample size (>2000) underestimated the number of phenotypes under some conditions (eg, number of time points <11). Increasing the number of data points resulted in an increase in the optimal number of phenotypes, but an identical number of randomly selected follow-up points led to different solutions. A variable selection algorithm identified 8 informative time points (months 18, 42, 57, 81, 91, 140, 157, and 166). The proportion of asthmatic patients at age 23 to 24 years differed between phenotypes, whereas lung function was lower among persistent wheezers.ConclusionsSample size, frequency, and timing of data collection have a major influence on the number and type of wheeze phenotypes identified by using LCA in longitudinal data.

Occupations and Causative Agents among Work-Related Asthma Patients in Easy Asthma Clinic, Srinagarind Hospital, Khon Kaen, Thailand

Background: Work-related asthma (WRA) is the most common chronic occupational lung disease in developing countries and the second most common in developed countries. The median attributable risk of occupational asthma for the population is estimated to be 25%. In Thailand, there are no details on occupational and causative agents vis-a-vis WRA. Aims: Our aim was to describe the occupational and causative agents for WRA patients who attended the Easy Asthma Clinic (EAC), Srinagarind Hospital, Khon Kaen, Thailand. Methods: This was a descriptive study: 323 participants at the Easy Asthma Clinics were identified and interviewed prior to obtaining information related to WRA symptoms and its suspected causative agents. Descriptive statistics were used for proportions. Results: The proportion of asthma patients with WRA was 16.7%. The top three occupations that carried the highest risk were (a) school workers, (b) skilled agriculture, forestry, and fishery workers, and (c) manufacturing and wood workers. The top three most identified causative agents were chalk powder, smoke from burning grass/tree, and fumes from stainless steel production. Some 63.0% of WRA patients did not wear respiratory protection equipment at work and among those who did, none wore it correctly. Conclusions: Occupational history, causative agents, and history of asthma symptoms related to work help to determine the proportion of WRA patients. The results of the current study should thus encourage physicians to record patient occupation(s) and job descriptions, so as to remove identifiable factors, before airway remodelling occurs, which makes treatment more difficult and costly.

Real life profile of asthma and chronic obstructive pulmonary disease patients in Turkey.

Despite the presentation of similar symptoms, the airway diseases have different underlying pathophysiological processes and must be distinguished to enable the administration of appropriate treatment. In several studies the clinician- and patient-related causes of poor compliance to treatment in asthma/chronic obstructive pulmonary disease (COPD) patients have been evaluated. This study aimed to determine the clinical and sociodemographic characteristics of newly diagnosed treatment-naïve asthma and COPD patients in Turkey. This national, multicentre, prospective, observational study was conducted in 122 centres. A questionnaire including items related to demographic, clinical, laboratory parameters was applied. All patients were intended to be followed-up for 12 months. 1892 adult patients (1116 asthma and 776 COPD) from 122 centres were enrolled. Overall 95%, 86% and 65% of intermittent, mild persistent and moderate persistent asthma patients were over-treated. Among COPD patients, the percentages of over-treated patients were 66%, 79% and 82% for those with GOLD stage A, B and C. Physicians' adherence to guidelines was appropriate in 93% of severe persistent asthma patients and 89% of GOLD stage D COPD patients. Among patients with high compliance to treatment, proportion of asthma patients with total control was 44% and that of COPD patients at GOLD stage A was 41%. In consecutive two visits, this figure increased to 52% and 63% in asthma patients and 54% and 50% in COPD patients. The main findings are: (a) patients are frequently over-treated and (b) patients do not adhere to visits as expected, in both asthma and COPD.

Association Between Asthma and Sensitization to Allergens of Dermatophagoides pteronyssinus.

Little is known about the role of molecular diagnosis in house dust mite (HDM) allergy. In this study, we investigated the association between the sensitization profile of adolescent and adult HDM-allergic patients and asthma in a region with high rates of exposure to HDM. We conducted a cross-sectional study of 384 HDM-allergic patients (38.5%, males; median age, 28 years). A total of 368 patients (95.8%) had rhinitis, and 175 (45.6%) had asthma. Specific IgE (sIgE) to Dermatophagoides pteronyssinus, nDer p 1, rDer p 2, and rPen a 1 was measured in all patients. sIgE to Lepidoglyphus destructor was measured in patients (n=301) with a positive skin test result. Significantly higher concentrations of sIgE to Der p 1 and sIgE to Der p 2 were observed in patients with asthma than in those without asthma. The proportion of asthmatic patients was higher among individuals who reacted (≥0.35 kUA/L) to both Der p 1 and Der p 2 (147/291, 50.5%) than among those who reacted to only 1 allergen (either Der p 1 or Der p 2, 18/55, 32.7%) or neither allergen (10/38, 26.3%, P=.002). Reactivity to both allergens was associated with asthma after adjusting for age and sex (OR, 2.87; 95%CI, 1.32-6.20). Higher concentrations of sIgE to L destructor were observed in patients with asthma than in patients without asthma. Tropomyosin sIgE ≥0.35 kUA/L was detected in only 6 individuals (1.6%). L destructor may be a relevant allergen in high-exposure areas. Dual sensitization (ie, IgE to both Der p 1 and Der p 2) may help to identify HDM-allergic patients who are at risk of asthma.

Inhaled beclometasone dipropionate/formoterol fumarate extrafine fixed combination for the treatment of asthma

ABSTRACTInhaled therapy is often considered the cornerstone of asthma management and international guidelines recommend combination therapy of inhaled corticosteroids (ICS) and long-acting-beta2-agonists (LABA) in a large proportion of asthmatic patients. The effectiveness of ICS/LABA is dependent on the correct choice of device and proper inhalation technique, this influences drug delivery and distribution along the bronchial tree, including the most peripheral airways. The fixed combination of beclometasone dipropionate/formoterol fumarate (BDP/FF) is the only extrafine formulation available in pressurized metered dose inhaler (pMDI) and in dry powder inhaler (DPI). Here, we focus on the recent significant advances regarding BDP/FF fixed combination for the treatment of asthma.

FENO and AHR mannitol in patients referred to an out-of-hospital asthma clinic: a real-life study

Objective: Ongoing airway inflammation measured by fractional exhaled nitric oxide (FENO) and airway hyperresponsiveness (AHR) to mannitol are associated in selected asthma patients, but no evidence exists of this association in unselected asthma patients. The aim was to investigate the association between FENO and AHR to mannitol in unselected individuals with possible asthma. Methods: A real-life study on patients with possible asthma referred to a specialized asthma clinic. Data on asthma history, FEV1, FENO, atopy, smoking, treatment and AHR to mannitol were collected. Results: In 217 unselected patients with symptoms suggestive of asthma, FENO and response to mannitol were tested. Of the 141 who underwent both tests, 32 (23%) had FENO > 25 ppb, and 58 (41%) had AHR to mannitol. A significant association between high FENO and AHR was found (p < 0.001); 26% responded to mannitol despite a normal NO, and 8% had a high FENO but no AHR. Additionally, a weak association was found between log FENO and log response to mannitol (r = 0.32, p < 0.01). The area under the ROC curve for FENO as a predictor of AHR was 0.66 (95% CI 0.6–0.8) and for mannitol for having high FENO was 0.73 (95%CI 0.6–0.9). Conclusion: In a large sample of patients referred to an asthma clinic, an association was found between FENO and AHR to mannitol. However, a significant proportion of asthma patients had a normal FENO despite having AHR, suggesting that in some patients, AHR to mannitol is not driven by eosinophilic airway inflammation.

Comment on ‘Allergy and acute leukaemia in children with Down syndrome: a population study. Report from the Mexican Inter Institutional Group for the Identification of the Causes of Childhood Leukaemia (MIGICCL)’ – Is increased surveillance by hypersensitive immune system a reality or myth?

Sir, We read with great interest the study by Nunez-Enriquez et al (2013)' recently published in this journal. They conducted a multi-institutional population-based case–control study on children with Down syndrome and found that asthma is a risk factor of acute leukaemia development (odds ratio: 4.18 and 95% confidence interval: 1.47–11.87). However, other allergies had no effect on acute leukaemia development or were protective, in their experience. This study has revived an old question about effect of having allergies and chance of cancer development. Previous studies in this regard unveiled that allergies usually do not increase the risk of cancers, and in contrast, might be protective from cancer development (Vojtechova and Martin, 2009; Chen et al, 2011; Dikalioti et al, 2012). In allergic subjects, there is bone marrow involvement with reprogramming of bone marrow stem cells, regarded as ‘reflex nature of allergic disease' (Holt and Strickland, 2010). Allergic phenotype in an atopic child may lead to epigenetic reprogramming that in turn affects immune surveillance by increasing antigen-presenting cell activity (Holt and Strickland, 2010). In addition, recent studies have demonstrated that serum eosinophil count is inversely associated with colorectal cancer development (Prizment et al, 2011). Hence, it seems that increased surveillance by hyperactive immune system of allergic patients is a reality. Here, the main question is ‘why was asthma found as a risk factor of acute leukaemia development?'. The method of allergy diagnosis and definition of allergic conditions affect categorisation of patients into different allergic groups, particularly with regard to recruitment of patients from different institutions. Moreover, considerable proportion of asthmatic patients might also have rhinitis, skin allergies or food allergies. Asthma and allergic rhinitis are too close in which more than half of asthmatic patients have also allergic rhinitis and up to 40% of allergic rhinitis patients experience asthma (Bousquet et al, 2012; Aryan et al, 2013). Skin allergies and food allergies are other allergic conditions that are common in asthmatics, in such a way up to 15% of asthmatics have food allergies (Fiocchi et al, 2013). It is not clear in this study that how investigators categorised patients who had several allergic conditions and it might affect their results. Another point is that wheezing in Down syndrome children is not likely to be asthma and asthma misclassification is possible to be occurred. It has been shown that Down syndrome children might experience episodes of wheezing mimicking asthma phenotype. Weijerman et al 2011 studied recurrent wheeze in 173 Down syndrome children and found that none of Down syndrome children below 4 years of age had asthma according to international guidelines, and only 3.1% of overall Down syndrome children were actually asthmatic. Weijerman et al 2011 demonstrated that 46% of wheezes in Down syndrome children were due to congenital heart defects. In addition, neither of increased immunoglobulin-E level nor evidence of aeroallergen sensitisation was found in these children (Weijerman et al, 2011). Hence, the diagnosis of asthma should be made more carefully in Down syndrome patients and only reliance of parent's memory might probably lead to misclassification of asthma in Down syndrome children. Moreover, not all asthmatic Down syndrome children have allergy, and in contrast, asthma in Down syndrome patients seem to be non-allergic (Weijerman et al, 2011). Collectively, the results of this study regarding asthma might be affected by misdiagnosis and misclassification of asthma as an allergic condition. On the other hand, Down syndrome is a primary immune deficiency characterised by lymphopenia, thrombocytopenia, and vulnerability to autoimmune and infectious diseases. Down syndrome children have increased susceptibility to respiratory syncytial virus infections, a known risk factor of asthma, thus they may experience manifestations quasi-asthma or actually develop asthma (Bloemers et al, 2010). Down syndrome patients have also inherited risk of acute leukaemia development. Accumulating evidences show that several genes on chromosome 21 have relevant functions in haematopoiesis and their qualitative or quantitative changes affect blood cells. Transient abnormal haematopoiesis and acute myeloid leukaemia are more likely to develop in Down syndrome children with GATA1 mutation (Maclean et al, 2012; Toki et al, 2013). It indicates that regardless of role of environmental factors, inborn genetic defects in Down syndrome children affect haematopoietic cell biology and cause leukaemogenesis. Down syndrome might be a confounder in relation between asthma and acute leukemia. Altogether, Down syndrome may be considered as a cause of both asthma and acute leukaemia and drawing a causative link from asthma to acute leukaemia in this setting seems a raw conclusion.

Lung Volume Abnormalities and its Correlation to Spirometric and Demographic Variables in Adult Asthma

Background. Presence of airflow obstruction in asthma has been based on a fixed FEV1(forced expiratory volume at 1 second)/FVC (forced vital capacity) ratio abnormality. The accuracy of FEV1/FVC ratio in diagnosing airflow obstruction remains controversial. Lung volume abnormalities have been observed in severe asthma. We utilized simultaneously measured spirometry and lung volume to determine the utility of residual volume (RV)/total lung capacity (TLC) ratio in diagnosing airflow obstruction and to identify predictors of abnormal RV in asthmatic subjects. Methods. Data from physician-diagnosed asthmatics referred for lung function tests were collected retrospectively. Patient demographics and lung function data were analyzed using general linear modeling. Results. Of the 321 subjects, 221 were female (69%). The ethnicity was Caucasian in 157 (49%), Hispanic in 131 (41%), and African-American in 33 (10%). The percentage of subjects with FEV1/FVC ratio <70%, FEV1-predicted <80%, and FEF25–75% <65% were 25%, 25%, and 38%, respectively. Fifty-two and fifty-seven percent of the patients had abnormal residual volume and abnormal RV/TLC ratio, respectively. A significant bronchodilator response was observed in 32% of the patients. A positive correlation was observed between RV to age (r = 0.4) and height (r = 0.3). A negative correlation was observed between RV to FEF25–75% (r = 0.5) and body weight (r = 0.07). There was no significant correlation between FEV1 reversibility and residual volume (r = 0.1). RV correlated significantly better with FEF25–75% (r2 = 0.25) than FEV1 (r2 = 0.16). Conclusion. A significant proportion of asthmatic patients have elevated residual volume and abnormal RV/TLC ratio in the presence of normal FEV1/FVC ratio and absence of significant bronchodilator response. The clinical significance of these findings in asthma needs further prospective study.

Allergen-Induced Inflammation

Allergen-induced inflammation manifests as allergic asthma, dermatitis, rhinitis, conjunctivitis, food allergies, and life- threatening anaphylaxis. Allergic reactions consist of an acute phase hypersensitivity reaction and late phase inflammation. Current therapeutic strategies consist of immunotherapy to induce tolerance to an allergen or pharmacotherapy to treat either the acute phase reaction or the chronic inflammation associated with allergic disease. For bronchial asthma, the allergic disease with the greatest worldwide burden, three medications (β2-adrenoceptor agonists, glucocorticoids and leukotriene antagonists) are the mainstays of therapy, which when used alone or in combination control asthma symptoms in many asthmatics. A recent anti-IgE therapy has benefited some difficult to manage patients, however a significant proportion of asthma patients do not respond well to currently available drugs. There is a need for new effective lost-cost therapies for asthma and other allergic diseases to complement existing therapies and improve long-term outcomes. There are several potential therapeutic targets including transcription factors, cytokines, chemokines and their receptors, proteases, and cell adhesion molecules. Within the next generation of anti-allergy drugs one or more will probably be a peptide or a peptide mimetic.

Persistent airway inflammation and bronchial hyperresponsiveness in patients with totally controlled asthma

A proportion of asthmatic patients can achieve total control according to the Global Initiative for Asthma/National Institute of Health guidelines. The aim of this study was to investigate whether total control of asthma is accompanied by the remission of airway inflammation and bronchial hyperresponsiveness. We assessed the number of eosinophil and the levels of eosinophil cationic protein (ECP) and interleukin (IL)-5 in induced sputum and bronchial responsiveness to methacholine in 76 patients with totally controlled asthma in comparison with 30 current untreated asthmatics and 20 healthy subjects. We found significantly higher number of eosinophil and higher levels of ECP and IL-5 in the total control group than those in healthy subjects (6.9% +/- 3.6% and 1.3% +/- 1.1%, 129.0 +/- 53.8 mug/l and 48.9 +/- 20.4 mug/l, 22.1 +/- 15.2 mug/l and 10.6 +/- 5.2 mug/l, respectively; p < 0.001), but lower than those in current asthma group (16.2% +/- 8.6%, 362.2 +/- 151.6 mug/l, 50.6 +/-25.8 mug/l, respectively; p < 0.001). Sixty-five (85.5%) patients with totally controlled asthma showed positive methacholine challenge test. In the total control group, number of eosinophil and the levels of ECP and IL-5 in induced sputum of patients with negative methacholine challenge test were significantly lower than those in subjects with positive methacholine challenge test (p < 0.001), whereas sputum number of eosinophil and the levels of ECP and IL-5 in patients with negative methacholine challenge test and those of healthy subjects were similar (p > 0.05). The results of this study suggest that airway inflammation and bronchial hyperresponsiveness still persisted during total control of asthma.

Lung function, asthma paradox, atopy, and risk factors in Mexican spirometry-diagnosed asthmatic patients

Despite long-term studies, still not much is known about the asthma triggering factors and its sometimes controversial results. Probably one of the major problems of controversy is the lack of specific and accurate diagnosis of this disease. The aim of this study was to assess lung function, atopy, and environmental factors in spirometry-diagnosed asthmatic patients. Time series of daily counts of hospital emergency admissions were constructed for known asthmatic subjects. Spirometry, chest radiograph, arterial gasometry, skin tests, environmental SO2 levels, and climatic parameters were evaluated. Family asthma history was observed in a high proportion of asthmatic patients and it correlated marginally with severity of asthma. A seasonal trend in asthma frequency was recorded and it was more common in the urban area and in those living in the margins of the city. The most frequent asthma type recorded was the severe persistent asthma. More than 50% of subjects had subresponse to bronchodilator; asthma paradox was recorded in 10.8%. Positive skin tests were observed in 36.9% and SO2 levels did not correlate with asthma attacks. Paradox asthma or tolerance may be developed by asthmatic subjects during chronic treatment with short-acting 92-agonists. To avoid side effects and to decrease the morbidity and mortality associated with the usage of antiasthma medications, it is essential to identify quickly those subjects that respond abnormally to the short-acting P2-agonist.

Acute Impact of Volcanic Ash on Asthma Symptoms and Treatment

Information about the impacts of disasters on health is useful for establishing hazard prediction maps and action plans of disaster management. This study aims at learning effective asthma management from the volcano disaster of Mount Asama eruption in Japan on September 1, 2004. We conducted a cross-sectional study to assess the acute impact of volcanic ash on asthma symptoms and their treatment changes by using a questionnaire completed by 236 adult asthmatic patients and their physicians. In the ashfall over 100g/m2 area, 42.9 percent of asthma patients suffered exacerbations, PEF decreased, asthma treatments increased, and inhalation of beta2 stimulants was used most for exacerbated asthma. Compared to severe asthma patients, mild and moderate asthma patients were most at risk. Severe asthma patients were not affected since most of them knew their asthma status was severe, and did not go outside and kept windows closed. Deteriorated asthma symptoms of wheezing, chest tightness and cough appeared in the ashfall over 100g/m2 area. Ash contained inhalable 10microm diameter particles, and included high concentrations of airway toxic substrates of silica. These data suggest that ashfall over 100 g/m2 is harmful, access to these areas by asthma patients needs to be restricted, and these areas need to improve asthma treatment. In addition, the increase in the proportion of asthma patients with wheeze and cough are diagnostic clues for ash-induced asthma in affected areas, and can be used by doctors to tell whether patients are receiving sufficient asthma treatment.

Glucocorticoid-induced apoptosis in human eosinophils: mechanisms of action.

Prominent blood and tissue eosinophilia is clinically manifested in a number of inflammatory states, particularly in allergic diseases. Corticosteroids are the most effective anti-inflammatory drugs used in the treatment of eosinophilic disorders, including bronchial asthma. Their beneficial effects result, among others, from (i) the suppression of the synthesis and the effects of eosinophil survival factors, (ii) the direct induction of eosinophil apoptosis and (iii) the stimulation of their engulfment by professional phagocytic cells. Failure of steroids to propagate apoptotic signals and to promote eosinophil clearance may explain the corticoresistance observed in a proportion of asthmatic patients. Accordingly, studies on the intracellular mechanisms involved in eosinophil corticosensitivity and resistance may provide a valuable tool for identifying new and selective molecular targets to therapeutically resolve otherwise persistent eosinophilic inflammation. In this review, the intracellular cascade of events involved in corticosteroid-mediated eosinophil apoptotic death is discussed and compared to the signalling pathway governing this process in the established model of dexamethasone-induced thymocyte apoptosis.

Improving the quality of care of patients with asthma: the example of patients with severely symptomatic disease.

The increasing economic burden of asthma care is incurred partly by patients with more severe symptoms. However, little is known about the characteristics of these severe asthma patients. This study examined sociodemographic, disease-specific characteristics and health care utilization that are related to asthma disease severity, for the purpose of identifying areas for treatment improvement. A total of 2927 asthma patients (12 years or older), who were continuously enrolled in one of three participating health plans for a 6-month study period and who responded to an asthma survey, were included in the study. Univariate and multivariate analyses were performed to examine the sociodemographic, disease-specific characteristics and health care utilization by asthma severity. About 25% of the patients reported experiencing severe asthma symptoms. They were more likely to be African-Americans, Hispanics, women, patients with less than a college education, residents in the south-west, current smokers, and those receiving care from non-specialists. Severe asthmatics reported having less of an understanding of the clinical manifestation of asthma and the means to manage asthma exacerbation. Outpatient contacts did not differ significantly between severe and other patients, although their utilization of emergency room and inpatient care was significantly greater. This study suggests that a significant proportion of asthma patients is experiencing severe symptoms and barriers other than access to care prevent appropriate control of asthma. Poor control appears to be related to smoking, deficits in knowledge about self-care, not receiving medical care from a specialist, and inadequate use of medications.

Characterisation of asthma management in the Fallon Community Health Plan from 1988 to 1991.

In order to characterise asthma management in a managed care setting, we identified 10,301 patients who were diagnosed with asthma between 1 January 1988 and 31 December 1991 at a group model health maintenance organisation in central Massachusetts, US. We obtained for these patients automated utilisation files containing data on medications, hospitalisations, emergency room visits, office visits, and estimated costs of these services. The medication dispensed to the greatest proportion of patients was beta 2 agonists either by inhalation (56%) or orally (21%). Theophylline was dispensed to 23% of the patients. Maintenance therapy was inhaled anti-inflammatory medication was uncommon, as inhaled corticosteroids (17%) and sodium cromoglycate (cromolyn sodium) [8%] were dispensed to fewer patients than other asthma medications. Among patients who had been hospitalised in the previous year, 36% were presently receiving inhaled corticosteroids, and among patients who used at least one beta 2 agonist metered-dose inhaler per month, 49% were presently receiving inhaled corticosteroids. Economic analyses showed that only 8% of the patients had either a hospital admission or an emergency room visit, but hospital costs among these patients accounted for 25% of the total costs of asthma care. In addition, the top 10% most expensive patients accounted for 42% of the total cost of asthma care. We conclude that a substantial proportion of patients at increased risk of a severe attack, by virtue of having a recent hospitalisation, do not receive maintenance anti-inflammatory therapy, and that hospitalisations among a relatively small proportion of asthma patients contribute significantly to the cost of asthma care.