Discordance between asthma control clinical, physiological and inflammatory parameters in mild asthma

Post-COVID breathlessness: a mathematical model of respiratory processing in the brain

Breathlessness is among the most common post-COVID symptoms. In a considerable number of patients, severe breathlessness cannot be explained by peripheral organ impairment. Recent concepts have described how such persistent breathlessness could arise from dysfunctional processing of respiratory information in the brain. In this paper, we present a first quantitative and testable mathematical model of how processing of respiratory-related signals could lead to breathlessness perception. The model is based on recent theories that the brain holds an adaptive and dynamic internal representation of a respiratory state that is based on previous experiences and comprises gas exchange between environment, lung and tissue cells. Perceived breathlessness reflects the brain's estimate of this respiratory state signaling a potentially hazardous disequilibrium in gas exchange. The internal respiratory state evolves from the respiratory state of the last breath, is updated by a sensory measurement of CO2 concentration, and is dependent on the current activity context. To evaluate our model and thus test the assumed mechanism, we used data from an ongoing rebreathing experiment investigating breathlessness in patients with post-COVID without peripheral organ dysfunction (N = 5) and healthy control participants without complaints after COVID-19 (N = 5). Although the observed breathlessness patterns varied extensively between individual participants in the rebreathing experiment, our model shows good performance in replicating these individual, heterogeneous time courses. The model assumes the same underlying processes in the central nervous system in all individuals, i.e., also between patients and healthy control participants, and we hypothesize that differences in breathlessness are explained by different weighting and thus influence of these processes on the final percept. Our model could thus be applied in future studies to provide insight into where in the processing cascade of respiratory signals a deficit is located that leads to (post-COVID) breathlessness. A potential clinical application could be, e.g., the monitoring of effects of pulmonary rehabilitation on respiratory processing in the brain to improve the therapeutic strategies.

Airway inflammation and hyperresponsiveness in subjects with respiratory symptoms and normal spirometry

BACKGROUND

Subjects without a previous history of asthma, presenting with unexplained respiratory symptoms and normal spirometry, may exhibit airway hyperresponsiveness (AHR) in association with underlying eosinophilic (type 2 (T2)) inflammation, consistent with undiagnosed asthma. However, the prevalence of undiagnosed asthma in these subjects is unknown.

METHODS

In this observational study, inhaled corticosteroid-naïve adults without previously diagnosed lung disease reporting current respiratory symptoms and showing normal pre- and post-bronchodilator spirometry underwent fractional exhaled nitric oxide (F _ENO) measurement, methacholine challenge testing and induced sputum analysis. AHR was defined as a provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 s (PC₂₀) <16 mg·mL^-1 and T2 inflammation was defined as sputum eosinophils >2% and/or F _ENO >25 ppb.

RESULTS

Out of 132 subjects (mean±sd age 57.6±14.2 years, 52% female), 47 (36% (95% CI 28-44%)) showed AHR: 20/132 (15% (95% CI 9-21%)) with PC₂₀ <4 mg·mL^-1 and 27/132 (21% (95% CI 14-28%)) with PC₂₀ 4-15.9 mg·mL^-1. Of 130 participants for whom sputum eosinophils, F _ENO or both results were obtained, 45 (35% (95% CI 27-43%)) had T2 inflammation. 14 participants (11% (95% CI 6-16%)) had sputum eosinophils >2% and PC₂₀ ≥16 mg·mL^-1, suggesting eosinophilic bronchitis. The prevalence of T2 inflammation was significantly higher in subjects with PC₂₀ <4 mg·mL^-1 (12/20 (60%)) than in those with PC₂₀ 4-15.9 mg·mL^-1 (8/27 (30%)) or ≥16 mg·mL^-1 (25/85 (29%)) (p=0.01).

CONCLUSIONS

Asthma, underlying T2 airway inflammation and eosinophilic bronchitis may remain undiagnosed in a high proportion of symptomatic subjects in the community who have normal pre- and post-bronchodilator spirometry.

Critical evaluation of asthma biomarkers in clinical practice

The advent of personalized medicine has revolutionized the whole approach to the management of asthma, representing the essential basis for future developments. The cornerstones of personalized medicine are the highest precision in diagnosis, individualized prediction of disease evolution, and patient-tailored treatment. To this aim, enormous efforts have been established to discover biomarkers able to predict patients' phenotypes according to clinical, functional, and bio-humoral traits. Biomarkers are objectively measured characteristics used as indicators of biological or pathogenic processes or clinical responses to specific therapeutic interventions. The diagnosis of type-2 asthma, prediction of response to type-2 targeted treatments, and evaluation of the risk of exacerbation and lung function impairment have been associated with biomarkers detectable either in peripheral blood or in airway samples. The surrogate nature of serum biomarkers, set up to be less invasive than sputum analysis or bronchial biopsies, has shown several limits concerning their clinical applicability. Routinely used biomarkers, like peripheral eosinophilia, total IgE, or exhaled nitric oxide, result, even when combined, to be not completely satisfactory in segregating different type-2 asthma phenotypes, particularly in the context of severe asthma where the choice among different biologics is compelling. Moreover, the type-2 low fraction of patients is not only an orphan of biological treatments but is at risk of being misdiagnosed due to the low negative predictive value of type-2 high biomarkers. Sputum inflammatory cell analysis, considered the highest specific biomarker in discriminating eosinophilic inflammation in asthma, and therefore elected as the gold standard in clinical trials and research models, demonstrated many limits in clinical applicability. Many factors may influence the measure of these biomarkers, such as corticosteroid intake, comorbidities, and environmental exposures or habits. Not least, biomarkers variability over time is a confounding factor leading to wrong clinical choices. In this narrative review, we try to explore many aspects concerning the role of routinely used biomarkers in asthma, applying a critical view over the "state of the art" and contemporarily offering an overview of the most recent evidence in this field.

Dissociating breathlessness symptoms from mood in asthma

It is poorly understood why asthma symptoms are often discordant with objective medical tests. Differences in interoception (perception of internal bodily processes) may help explain symptom discordance, which may be further influenced by mood and attention. We explored inter-relationships between interoception, mood and attention in 63 individuals with asthma and 30 controls. Questionnaires, a breathing-related interoception task, two attention tasks, and standard clinical assessments were performed. Questionnaires were analysed using exploratory factor analysis, and linear regression examined relationships between measures. K-means clustering also defined asthma subgroups. Two concordant asthma subgroups (symptoms related appropriately to pathophysiology, normal mood) and one discordant subgroup (moderate symptoms, minor pathophysiology, low mood) were found. In all participants, negative mood correlated with decreased interoceptive ability and faster reaction times in an attention task. Our findings suggest that interpreting bodily sensations relates to mood, and this effect may be heightened in subgroups of individuals with asthma.

The Filter Detection Task for measurement of breathing-related interoception and metacognition

The study of the brain's processing of sensory inputs from within the body ('interoception') has been gaining rapid popularity in neuroscience, where interoceptive disturbances are thought to exist across a wide range of chronic physiological and psychological conditions. Here we present a task and analysis procedure to quantify specific dimensions of breathing-related interoception, including interoceptive sensitivity, decision bias, metacognitive bias, and metacognitive performance. Two major developments address some of the challenges presented by low trial numbers in interoceptive experiments: (i) a novel adaptive algorithm to maintain task performance at 70-75% accuracy; (ii) an extended hierarchical metacognitive model to estimate regression parameters linking metacognitive performance to relevant (e.g. clinical) variables. We demonstrate the utility of the task and analysis developments, using both simulated data and three empirical datasets. This methodology represents an important step towards accurately quantifying interoceptive dimensions from a simple experimental procedure that is compatible with clinical settings.

Value of bronchial reversibility to salbutamol, exhaled nitric oxide and responsiveness to methacholine to corroborate the diagnosis of asthma in children

INTRODUCTION AND OBJECTIVES

Functional and inflammatory measures have been recommended to corroborate asthma diagnosis in schoolchildren, but the evidence in this regard is conflicting. We aimed to determine, in real-life clinical situation, the value of spirometry, spirometric bronchial reversibility to salbutamol (BDR), bronchial responsiveness to methacholine (MCT) and fractional exhaled nitric oxide (FENO), to corroborate the diagnosis of asthma in children on regular inhaled corticosteroids (ICS) referred from primary care.

METHODS

One hundred and seventy-seven schoolchildren with mild-moderate persistent asthma, on treatment with regular ICS, participated in the study. Abnormal tests were defined as FENO ≥ 27 ppb, BDR (FEV1 ≥ 12%) and methacholine PC20 ≤ 4 mg/mL.

RESULTS

The proportions of positive BDR, FENO and MCT, were 16.4%, 33.3%, and 87.0%, respectively. MCT was associated with FENO (p < 0.03) and BDR (p = 0.001); FENO was associated with BDR (p = 0.045), family history of asthma (p = 0.003) and use of asthma medication in the first two years of life (p = 0.004). BDR was significantly related with passive tobacco exposure (p = 0.003).

CONCLUSIONS

Spirometry, BDR and BDR had a poor performance for corroborating diagnosis in our asthmatic children on ICS treatment; on the contrary, MCT was positive in most of them, which agrees with previous reports. Although asthma tests are useful to corroborate asthma when positive, clinical diagnosis remains the best current approach for asthma diagnosis, at least while better objective and feasible measurements at the daily practice are available. At present, these tests may have a better role for assessing the management and progression of the condition.

Asthma: A Loss of Post-natal Homeostatic Control of Airways Smooth Muscle With Regression Toward a Pre-natal State

The defining feature of asthma is loss of normal post-natal homeostatic control of airways smooth muscle (ASM). This is the key feature that distinguishes asthma from all other forms of respiratory disease. Failure to focus on impaired ASM homeostasis largely explains our failure to find a cure and contributes to the widespread excessive morbidity associated with the condition despite the presence of effective therapies. The mechanisms responsible for destabilizing the normal tight control of ASM and hence airways caliber in post-natal life are unknown but it is clear that atopic inflammation is neither necessary nor sufficient. Loss of homeostasis results in excessive ASM contraction which, in those with poor control, is manifest by variations in airflow resistance over short periods of time. During viral exacerbations, the ability to respond to bronchodilators is partially or almost completely lost, resulting in ASM being "locked down" in a contracted state. Corticosteroids appear to restore normal or near normal homeostasis in those with poor control and restore bronchodilator responsiveness during exacerbations. The mechanism of action of corticosteroids is unknown and the assumption that their action is solely due to "anti-inflammatory" effects needs to be challenged. ASM, in evolutionary terms, dates to the earliest land dwelling creatures that required muscle to empty primitive lungs. ASM appears very early in embryonic development and active peristalsis is essential for the formation of the lungs. However, in post-natal life its only role appears to be to maintain airways in a configuration that minimizes resistance to airflow and dead space. In health, significant constriction is actively prevented, presumably through classic negative feedback loops. Disruption of this robust homeostatic control can develop at any age and results in asthma. In order to develop a cure, we need to move from our current focus on immunology and inflammatory pathways to work that will lead to an understanding of the mechanisms that contribute to ASM stability in health and how this is disrupted to cause asthma. This requires a radical change in the focus of most of "asthma research."

Breathlessness and the brain: the role of expectation

PURPOSE OF REVIEW

Breathlessness debilitates countless people with a wide range of common diseases. For some people, the experience of breathlessness is poorly explained by the findings of medical tests. This disparity complicates diagnostic and treatment options and means that disease-modifying treatments do not always have the expected effect upon symptoms. These observations suggest that brain processing of respiratory perceptions may be somewhat independent of disease processes. This may help to explain the dissonance observed in some patients between physical disease markers and the lived experience of breathlessness.

RECENT FINDINGS

A body of breathlessness research using functional neuroimaging has identified a relatively consistent set of brain areas that are associated with breathlessness. These areas include the insula, cingulate and sensory cortices, the amygdala and the periaqueductal gray matter. We interpret these findings in the context of new theories of perception that emphasize the importance of distributed brain networks. Within this framework, these perceptual networks function by checking an internal model (a set of expectations) against peripheral sensory inputs, instead of the brain acting as a passive signal transducer. Furthermore, other factors beyond the physiology of breathlessness can influence the system.

SUMMARY

A person's expectations and mood are major contributors to the function of the brain networks that generate perceptions of breathlessness. Breathlessness, therefore, arises from inferences made by the brain's integration of both expectations and sensory inputs. By better understanding individual differences across these contributing perceptual factors, we will be better poised to develop targeted and individualized treatments for breathlessness that could complement disease-modifying therapies.

A novel nutritional intervention improves lung function in overweight/obese adolescents with poorly controlled asthma: the Supplemental Nutrition in Asthma Control (SNAC) pilot study

Asthma in the obese is often severe, difficult to treat, and characterized by less eosinophilic inflammation than asthma in the nonobese. Obesity-associated metabolic dysregulation may be a causal factor. We previously reported that a nutrient- and fiber-dense bar [Children's Hospital Oakland Research Institute (CHORI)-bar], which was designed to fill gaps in poor diets, improved metabolism in healthy overweight/obese (OW/OB) adults. In this pilot trial, OW/OB adolescents with poorly controlled asthma were randomized to weekly nutrition/exercise classes with or without twice-daily CHORI-bar consumption. Intent-to-treat analysis did not indicate CHORI-bar-specific effects. However, restricting the analysis to participants with acceptable compliance and a relatively low fraction of exhaled nitric oxide (FENO; <50/ ppb, a surrogate for noneosinophilic asthma; study participants: CHORI-bar, n = 16; controls, n = 15) indicated that CHORI-bar-specific, significant improvements in lung function (forced vital capacity, percent-predicted forced expiratory volume in 1 s, and percent-predicted forced expiratory flow between 25 and 75% of forced vital capacity), primarily in participants with low chronic inflammation (high-sensitivity C-reactive protein <1.5 mg/L). (We previously observed that chronic inflammation blunted CHORI-bar-induced metabolic improvements in healthy OW/OB adults.) Lung function improvement occurred without weight loss and was independent of improvements in metabolic and anthropometric end points and questionnaire-based measures of asthma control and quality of life. This study suggests that a nutritional intervention can improve lung function in OW/OB adolescents with asthma and relatively low FENO without requiring major changes in dietary habits, lifestyle, or weight loss and that this effect is blunted by chronic inflammation.-Bseikri, M., McCann, J. C., Lal, A., Fong, E., Graves, K., Goldrich, A., Block, D., Gildengoren, G. L., Mietus-Snyder, M., Shigenaga, M., Suh, J., Hardy, K., Ames, B. N. A novel nutritional intervention improves lung function in overweight/obese adolescents with poorly controlled asthma: the Supplemental Nutrition in Asthma Control (SNAC) pilot study.

New and Anticipated Therapies for Severe Asthma

Asthma is frequently undertreated, resulting in a relatively high prevalence of patients with uncontrolled disease, characterized by the presence of symptoms and risk of adverse outcomes. Patients with uncontrolled asthma have a higher risk of morbidity and mortality, underscoring the importance of identifying uncontrolled disease and modifying management plans to improve control. Several assessment tools exist to evaluate control with various cutoff points and measures, but these tools do not reliably correlate with physiological measures and should be considered a supplement to physiological tests. When attempting to improve control in patients, nonpharmacological interventions should always be attempted before changing or adding pharmacotherapies. Among patients with severe, uncontrolled asthma, individualized treatment based on asthma phenotype and eosinophil presence should be considered. The efficacy of the anti-IgE antibody omalizumab has been well established for patients with allergic asthma, and novel biologic agents targeting IL-5, IL-13, IL-4, and other allergic pathways have been investigated for patients with allergic or eosinophilic asthma. Fevipiprant (a CRT_H2 [chemokine receptor homologous molecule expressed on Th2 cells] antagonist) and imatinib (a tyrosine kinase inhibition) are examples of nonbiologic therapies that may be useful for patients with severe, uncontrolled asthma. Incorporation of new and emerging treatment into therapeutic strategies for patients with severe asthma may improve outcomes for this patient population.

Prevalence, determinants and clinical correlates of vitamin D deficiency in adults with inhaled corticosteroid-treated asthma in London, UK

Vitamin D deficiency is common in children with asthma, and it associates with poor asthma control, reduced forced expiratory volume in one second (FEV₁) and increased requirement for inhaled corticosteroids (ICS). Cross-sectional studies investigating the prevalence, determinants and clinical correlates of vitamin D deficiency in adults with asthma are lacking. We conducted a multi-centre cross-sectional study in 297 adults with a medical record diagnosis of ICS-treated asthma living in London, UK. Details of potential environmental determinants of vitamin D status, asthma control and medication use were collected by questionnaire; blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction, and participants underwent measurement of weight, height and fractional exhaled nitric oxide concentration (FeNO), spirometry and sputum induction for determination of lower airway eosinophil counts (n=35 sub-group). Thirty-five single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DBP, DHCR7, RXRA, CYP2R1, CYP27B1, CYP24A1, CYP3A4 CYP27A1, LRP2, CUBN, VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration, and to determine whether vitamin D status was independently associated with Asthma Control Test (ACT) score, ICS dose, FeNO, forced vital capacity (FVC), FEV₁ or lower airway eosinophilia. Mean serum 25(OH)D concentration was 50.6nmol/L (SD 24.9); 162/297 (54.5%) participants were vitamin D deficient (serum 25(OH)D concentration <50nmol/L). Lower vitamin D status was associated with higher body mass index (P=0.014), non-White ethnicity (P=0.036), unemployment (P for trend=0.012), lack of vitamin D supplement use (P<0.001), sampling in Winter or Spring (P for trend <0.001) and lack of a recent sunny holiday abroad (P=0.030), but not with potential genetic determinants. Vitamin D status was not found to associate with any marker of asthma control investigated. Vitamin D deficiency is common among UK adults with ICS-treated asthma, and classical environmental determinants of serum 25(OH)D operate in this population. However, in contrast to studies conducted in children, we found no association between vitamin D status and markers of asthma severity or control.

Impact of Adding a Decision Aid to Patient Education in Adults with Asthma: A Randomized Clinical Trial

BACKGROUND

Not providing adequate patient education interventions to asthma patients remains a major care gap. To help asthma patients and caregivers discuss inhaled controller medication use, our team has previously developed a decision aid (DA). We sought to assess whether adding this DA to education interventions improved knowledge, decisional conflict, and asthma control among adults with asthma.

METHODS

A parallel clinical trial (NCT02516449). We recruited adults with asthma, aged 18 to 65 years, prescribed inhaled controller medication to optimize asthma control. Educators randomly allocated participants either to the education + DA or to the education group. At baseline and two-month follow-up, we measured asthma knowledge (primary outcome) with a validated self-administered questionnaire (score -37 to +37). Secondary outcomes included decisional conflict and asthma control. Blinded assessors collected data. Between the two time points, the within- and between-group changes were estimated by generalized linear mixed models.

RESULTS

Fifty-one participants (response rate: 53%; age: 44 ± 13 years; women: n = 32) were randomized either to the education + DA group (n = 26) or to the education group (n = 25), and included in statistical analyses. Between baseline and follow-up, mean [95% CI] knowledge scores increased from 21.5 [19.9-23.2] to 25.1 [23.1-27.0] in the education + DA group (P = 0.0002) and from 24.0 [22.3-25.7] to 26.0 [24.0-28.0] in the education group (P = 0.0298). In both of the groups, decisional conflict and asthma control improved. There were no differences between groups.

CONCLUSIONS

Education improved knowledge, decisional conflict, and asthma control whether the DA was added or not.

The Rhinitis Control Scoring System: Development and validation

BACKGROUND

Allergic rhinitis is a common health problem that requires regular monitoring of symptoms to provide adequate treatment. There is a need to develop rhinitis control assessment tools that are meaningful and easy to interpret by both the patient and the practitioner.

OBJECTIVE

To develop a simple, easy-to-interpret instrument, the Rhinitis Control Scoring System (RCSS), for the assessment of rhinitis control, as a companion tool to the Asthma Control Scoring System previously validated.

METHODS

After a literature review and based on the Allergic Rhinitis and its Impact on Asthma guidelines, allergic rhinitis control parameters were identified. The draft items were subjected to cognitive debriefing regarding instructions, wordings, and response options. The second version of the draft was then pretested and modified according to the results. The final draft of the RCSS, based on the intensity and frequency of symptoms, was then pilot tested with 50 subjects who had allergic rhinitis for validation of some psychometric properties. Each subject completed the RCSS in addition to other rhinitis instruments. They also had nasal peak inspiratory flow measurements.

RESULTS

The RCSS showed good internal consistency (Cronbach α = 0.84). There was strong criterion validity between the RCSS scores and the other instruments. The discriminant validity demonstrated as mean RCSS scores differed significantly across groups of patients with different Total Nasal Symptom Score severity (F = 58.8, p < 0.0001).

CONCLUSIONS

This pilot study showed that the RCSS is a simple tool to assess and quantify rhinitis control by using a percentage score. This questionnaire allows the quantification of rhinitis control and, therefore, may help guide therapeutic interventions. Combined with the Asthma Control Scoring System, it can provide a global assessment of rhinitis and asthma control. Clinical Trial number NCT00967967.

Discrepancies between asthma control criteria in asthmatic patients with and without obesity

OBJECTIVE

To compare the prevalence of discrepancies between clinical, physiological, and inflammatory asthma control parameters between patients with asthma and obesity and patients with asthma but not obesity using the Asthma Control Scoring System (ACSS).

METHODS

A retrospective analysis of demographic data and ACSS scores was performed in two groups of patients with asthma (74 with obesity and 74 without obesity) paired for sex, age, and asthma severity. Scores from each asthma control parameter-clinical (respiratory symptoms), physiological (forced expiratory volume in 1 s), and inflammatory (sputum eosinophil percentage)-were compared. Discrepancy was defined as a >20% difference between two scores.

RESULTS

The prevalence of discrepancies between scores was similar between asthma patients with or without obesity. A sub-analysis on patients with uncontrolled asthma (ACSS global score <80%) showed a higher prevalence of discrepancies between the clinical and physiological scores in subjects with obesity, the clinical score being higher than the physiological one in most (87%) cases.

CONCLUSIONS

Subjects with obesity and uncontrolled asthma show higher clinical scores than physiological scores, suggesting an under-evaluation of asthma symptoms. Future studies are needed to evaluate the influence of obesity on each type of asthma symptom.

What lies beyond Asthma Control Test: Suggestions for clinical practice

BACKGROUND

Asthma Control Test (ACT ™) validity relies on Global Initiative for Asthma (GINA) definition of control. It includes neither reversibility nor inflammation assessment despite their importance as hallmark of asthma, partially unrelated to symptoms. Furthermore though rhinitis may affect the patient's perception of asthma control, its impact on ACT accuracy has not been systematically evaluated.

OBJECTIVE

To explore ACT validity according to a definition of control including: forced expiratory volume in 1 s (FEV1) ≥ 80%, negative reversibility test, exhaled nitric oxide at a flow rate of 50 ml/s (FeNO) < 50 ppb.

RESULTS

177 asthmatics referring to our Unit have been studied. ACT with cut-off score ≥20 showed a good positive predictive value (83.5%) but low sensitivity (47.8%), specificity (66.7%), and negative predictive value (26.5%). ROC curves analysis indicates that ACT in patients with mild intermittent rhinitis is more reliable (AUC: 0.714; p < 0.05) than in patients with nasal polyposis/chronic rhino-sinusitis (AUC: 0.176; p > 0.05). Considering asthma classification, the probability that ACT detects patients with uncontrolled asthma is significantly higher in moderate persistent asthma subgroup than in mild persistent asthma one (OR 5.464; IC 95%: 2.5-11,9; p < 0.05).

CONCLUSIONS

As ACT mainly relies on patient's reported outcomes, it may not completely reflect the airways inflammation and airways obstruction. The presence and severity of rhinitis may affect ACT outcome. The awareness of the variables that could influence ACT evaluation is much more important in the primary care setting where ACT may often represent the only tool for asthma assessment.

Control of asthma in real life: still a valuable goal?

Although studies show that control of asthma can be achieved in the majority of patients, surveys repeatedly show that this is not the case in real life. Important measures to implement in order to achieve asthma control are trained healthcare professionals, a good patient–doctor relationship, patient education, avoidance of exposure to triggers, personalised management and adherence to treatment. These measures help the majority of asthma patients but have not yet been widely implemented and there should be a concerted action for their implementation. Moreover, further and focused research is needed in severe/refractory asthma.

Achieving asthma control requires implementation of evidence-based guidelines and further research into severe asthmahttp://ow.ly/KzrOp

Perceived 10-year change in respiratory health: reliability and predictive ability

OBJECTIVE

To investigate the usefulness of a self-reported respiratory health transition question over 10 years through reliability, ability to capture long-term asthma trajectory and predictive ability.

SETTINGS

In two 20-year cohorts (Asthma-E3N, n = 16,371, 61-88 years; EGEA, n = 1254, 27-82 years), perceived 10-year change in respiratory health ("Overall, in the last 10 years, do you think that your bronchial or respiratory health has changed?" if yes: "Has it improved/deteriorated?") was studied in relation with change in respiratory medication dispensation and lung function, with change in asthma status measured over the same period of time, and with subsequent asthma-related outcomes.

RESULTS

Perceived deterioration (14% in Asthma-E3N) was associated with increased dispensations of respiratory medications over time (from 17% with >2 dispensations in 2004 to 26% in 2010). Report of perceived deterioration (13% in EGEA) was related to a lung function decline steeper by 9.3 mL/year as compared to perceived improvement. In both cohorts, change (improvement or deterioration) was more often perceived by participants with than without asthma (>45% vs <20%) and was dominant among participants with persistent current asthma (77%). Perceived deterioration was related to poorer asthma control 7 years later and to higher use of oral corticosteroids in the following 18 months.

CONCLUSION

The proposed simple self-reported respiratory health transition question over 10 years allows predicting part of the long-term trajectory of asthma.

Identification of asthma phenotypes in a tertiary care medical center

BACKGROUND

Asthma affects 5% to 10% of the population and its severity is assessed using 4 parameters: lung function, symptom frequency, rescue inhaler use, and number of asthma exacerbations. Asthma is increasingly recognized as a clinical syndrome rather than a single disease. However, the current classification system fails to reflect the heterogeneous characteristics of the disease.

METHODS

A retrospective chart review of 139 patients with mild, moderate, and severe persistent asthma was performed. Variables including baseline and maximal forced expiratory volume over first second (percent predicted), and age of asthma onset were used to classify patients.

RESULTS

This yielded 5 clusters similar to Severe Asthma Research Program (SARP). Subjects in cluster 1 (n = 32) and cluster 2 (n = 47) had early-onset atopic asthma and reduced lung function but differed in medication requirement and health care utilization. Cluster 3 (n = 32) consisted of older obese women with late-onset asthma, less atopy, and mildly reduced forced expiratory volume over first second. Members of cluster 4 (n = 20) and cluster 5 (n = 8) had atopic asthma with severe obstruction but differed in bronchodilator response, age of onset, and oral corticosteroid use. Compared with SARP, our subjects were older, had a higher percentage of African Americans and obesity, and less severe asthma (P < 0.05). The observed clusters differed from SARP clusters in the following: (1) more frequent asthma exacerbations and medication use among cluster 1 and cluster 2; (2) lower medication use in cluster 3 and cluster 4; (3) although total health care utilization was similar, there were fewer emergency department visits in cluster 3 (P < 0.05).

CONCLUSIONS

The SARP algorithm may be used to classify diverse asthmatic populations into a clinically reproducible phenotypic cluster.

Failure in asthma control: reasons and consequences

Clinical research showed that asthma control is an achievable target. However, real-life observations suggest that a significant proportion of patients suffer from symptoms and report lifestyle limitations with a considerable burden on patient's quality of life. The achievement of asthma control is the result of the interaction among different variables concerning the disease pattern and patients' and physicians' knowledge and behaviour. The failure in asthma control can be considered as the result of the complex interaction among different variables, such as the role of guidelines diffusion and implementation, some disease-related factors (i.e., the presence of common comorbidities in asthma such as gastroesophageal reflux disease (GERD), sleep disturbances and obstructive sleep apnea (OSA), and rhinitis) or patient-related factors (i.e., adherence to treatment, alexithymia, and coping strategies). Asthma control may be reached through a tailored treatment plan taking into account the complexity of factors that contribute to achieve and maintain this objective.