Higher BMI is associated with worse asthma control and quality of life but not asthma severity

Stigma in Practice: Barriers to Health for Fat Women

In this paper, we explore barriers to health for fat people. By shifting the focus from what fat people do or do not do, neoliberal principles are replaced by a focus instead on structural and institutional policies, attitudes, and practices. This includes the impact of stigma on the health treatment and health-seeking behavior of fat people. For example, we consider the role that provider anti-fat attitudes and confirmation bias play in the failure to provide evidenced-based healthcare to fat patients. This is an autoethnographic paper, which provides the opportunity to read research from the perspective of fat scholars, framed by questions such as: can fat people have health? Is health itself a state of being, a set of behaviors, a commodity, a performance; perhaps the new social contract? As a co-written autoethnographic paper, one aspect of the evidence provided is the recorded experiences of the two fat authors. This includes writing from notes, journals, compiled and repeated experiences with medical professionals, family, and the community. Framed by feminist standpoint and supported by literature drawn from Fat Studies, Public Health, Obesity Research, and other interdisciplinary fields, this is a valuable opportunity to present an extended account of fat discrimination and the impact of the stigma fat people face through the medical profession and other sectors of the community, written by fat individuals. The paper concludes by considering the health pathways available to fat people. Special attention is paid to whether Bacon and Aphramor's Health at Every Size paradigm provides a path to health for fat individuals.

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.

Clinical characteristics of asthmatic patients with influenza-like illness and risk of severe exacerbations in Mexico

BACKGROUND

Patients with chronic inflammatory lung diseases, such as asthma, are at higher risk for influenza-like illness (ILI) complications. Viral infections are known to trigger asthma exacerbations, but a thorough description of the clinical characteristics of ILI-associated asthma exacerbations and the role of viruses as a risk factor for severe exacerbation (SE) in ILI has not been published yet.

OBJECTIVE

To investigate risk factors for SE in patients with ILI and asthma.

METHODS

Patients with ILI symptoms were recruited from 6 hospitals of Mexico (LaRed sites) during 2010 to 2014. Those with a previous asthma diagnosis and ILI symptoms and who were 5 years or older were included. Patients were assigned as cases or controls based on symptoms reported. SE was defined when participants presented with wheezing or dyspnea and required hospitalization.

RESULTS

A total of 486 patients with ILI and a diagnosis of asthma were included. There were no differences in the proportion, number, or type of viral illness among those with and without SE. Those with SE were less likely to report ILI symptoms. Muscle pain and nasal drip were predictors for patients not progressing to SE. A delay in seeking medical care was associated with SE (odds ratio, 2.93; 95% CI, 1.46-5.88).

CONCLUSION

The presence of a particular virus did not predict SE. ILI symptoms in asthma patients are not associated with severe exacerbation. Patients with asthma should be encouraged to seek early medical care when ILI symptoms are first noticed to prevent serious complications.

Obesity risk class and asthma outpatient service utilization by the middle aged and elderly in Taiwan

BACKGROUND

According to the estimates of the World Health Organization (WHO), there were about 300 million people in the world suffering from asthma in 2005. Among the risk factors of asthma is obesity, which was found to be significantly associated with asthma in recent decades.

OBJECTIVES

In this study, we analyze the relationship between obesity risk class and asthma outpatient service utilization by the middle-aged and elderly in Taiwan.

METHODS

Adopting data from the 2005 Nation Health Interview Survey (NHIS) and National Health Insurance Research Database (NHIRD), we first utilize latent class analysis (LCA) to identify obesity risk classes. Next, we utilize a logit and a negative binominal model to analyze the relationship between each obesity risk class and asthma outpatient service utilization.

RESULTS

Results indicate that compared with the "overweight/obese with low consumption of vegetable/fruit and little exercise" class, the classes "normal-weight with high consumption of vegetable/fruit and moderate exercise" and "overweight/obese with high consumption of vegetable/fruit and moderate exercise" tend to have low probabilities and less number of visits of utilizing asthma outpatient services.

CONCLUSIONS

Our results may constitute useful references for clinicians and government policy makers formulating strategies for asthma management and prevention. Better informed strategies for asthma management could, in turn, increase the efficiency of asthmatic patients' care, which could provide efficient assistance to the target group based on the obesity risk classes.

Challenges and Current Efforts in the Development of Biomarkers for Chronic Inflammatory and Remodeling Conditions of the Lungs

This review discusses biomarkers that are being researched for their usefulness to phenotype chronic inflammatory lung diseases that cause remodeling of the lung's architecture. The review focuses on asthma, chronic obstructive pulmonary disease (COPD), and pulmonary hypertension. Bio-markers of environmental exposure and specific classes of biomarkers (noncoding RNA, metabolism, vitamin, coagulation, and microbiome related) are also discussed. Examples of biomarkers that are in clinical use, biomarkers that are under development, and biomarkers that are still in the research phase are discussed. We chose to present examples of the research in biomarker development by diseases, because asthma, COPD, and pulmonary hypertension are distinct entities, although they clearly share processes of inflammation and remodeling.

Association between patterns of leisure time physical activity and asthma control in adult patients

Background

Physical activity has been shown to have various health benefits in patients with asthma, especially in children. However, there are still limited data on the nature of the association between physical activity and asthma control in adults.

Objective

The objective of the current study was to determine the nature of the association between physical activity and asthma control, with particular emphasis on the intensity of the activity and seasonal variations.

Methods

643 adult patients with objectively confirmed asthma (mean age (SD)=53 (15) years, 60% women) were interviewed by telephone. Patients completed the asthma control questionnaire (ACQ), the asthma quality of life questionnaire, and a 1-year physical activity recall questionnaire to assess leisure time physical activity (LTPA).

Results

Total LTPA was related to control (β (95% CI)=−0.013 (−0.030 to 0.006)), with those doing recommended levels of LTPA being nearly 2.5 times more likely to have good control compared with inactive patients. Analysis of seasonal exercise habits found that winter LTPA (β=−0.027 (−0.048 to −0.006)) was more strongly associated with ACQ scores than summer LTPA (β=−0.019 (−0.037 to −0.001)). Adjustment for age, sex, season of assessment, inhaled corticosteroid (ICS) dose, body mass index, and current smoking status reduced the strength of the relationships.

Conclusions

Data indicate that higher levels of LTPA are associated with better levels of asthma control in adult patients with asthma, and that this seems to be more pronounced among asthmatics who do the recommended levels of exercise.

Significant predictors of poor quality of life in older asthmatics

BACKGROUND

Morbidity and mortality from asthma are high in older adults and quality of life (QOL) might be lower, although standardized measurements of QOL have not been validated in this population.

OBJECTIVE

To determine predictors of asthma-related QOL in older adults.

METHODS

Allergy and pulmonary outpatients (n = 164) at least 65 years old with an objective diagnosis of asthma completed the Mini-Asthma Quality of Life Questionnaire (mAQLQ). Demographics, medical history, and mean value for daily elemental carbon attributable to traffic, a surrogate for diesel exposure, were obtained. Regression analysis was used to determine predictors of mAQLQ scores.

RESULTS

Total mAQLQ (mean ± SD 5.4 ± 1.1) and symptom, emotional, and activity domain scores were similar to those of younger populations, whereas environmental domain scores (4.4 ± 1.7) appeared lower. Poorer mAQLQ scores were significantly associated with emergency department visits (adjusted β [aβ] = -1.3, where β values indicate the strength and direction of association, P < .0001) and with poorer scores on the Asthma Control Questionnaire (aβ = -0.7, P < .0001). Greater ECAT exposure (aβ = -1.6, P < .02), female sex (aβ = -0.4, P < .006), body mass index of at least 30 kg/m(2) (aβ = -0.4, P < .01), gastroesophageal reflux (aβ = -0.4, P < .01), nonatopic status (aβ = -0.5, P < .002), and asthma onset before 40 years of age (aβ = -0.5, P < .004) were significantly associated with poorer mAQLQ scores.

CONCLUSION

The mAQLQ scores in older adults with stable asthma were similar to those in younger populations and were predictive of other measurements of asthma control, verifying that the mAQLQ is an appropriate tool in older adults with asthma. Traffic pollution exposure was the strongest predictor of poorer asthma-related QOL in older adults with asthma.

Prospective Study on the Relationship of Obesity to Asthma Impairment and Risk

BACKGROUND

Although studies consistently show an association between obesity and increased asthma incidence, the role of obesity in asthma control is less clear.

OBJECTIVE

The objective of this study was to evaluate the association between baseline body mass index (BMI) and measures of subsequent asthma control in a large real-world cohort of adults with persistent asthma.

METHODS

In Kaiser Permanente Southern California (KPSC), a large managed care organization, we identified adults with persistent asthma in 2006, continuous health plan enrollment in 2007 and 2008, and a BMI measurement in 2006 or 2007. Each patient's last BMI measure in 2006 or 2007 was categorized into a BMI group: normal (<25 kg/m(2)), overweight (25-29.9 kg/m(2)), or obese (≥30 kg/m(2)). Asthma control outcomes in 2008 included asthma hospitalizations or emergency department visits (EDHO), oral corticosteroid dispensings linked to an asthma encounter (OCS), and dispensing of ≥7 short-acting beta-agonist canisters (SABA7). Multivariable analyses were conducted to assess the relationships of BMI categories with the risk of the asthma control outcomes after controlling for potential confounders.

RESULTS

In the 10,233 eligible adults-after adjusting for potential demographic, comorbidity, and prior utilization confounders-we found an increased relative risk (RR) of EDHO in overweight and obese (RR 1.40, 95% CI 1.10-1.78) individuals. Only obesity was associated in adjusted analyses with a significant increased relative risk of SABA7 (RR 1.27, 95% CI 1.15-1.40).

CONCLUSIONS

Elevated BMI, particularly obesity, is associated with subsequent poor asthma control, especially in the risk domain (exacerbations). These findings further support the importance of facilitating weight loss in overweight and obese adults with asthma.

Increased body mass index predicts severity of asthma symptoms but not objective asthma traits in a large sample of asthmatics

AIM

To examine the relationship between body mass index (BMI) and different indicators of asthma severity in a large community-based sample of Danish adolescents and adults.

METHODS

A total of 1186 subjects, 14-44 years of age, who in a screening questionnaire had reported a history of airway symptoms suggestive of asthma and/or allergy, or who were taking any medication for these conditions were clinically examined. All participants were interviewed about respiratory symptoms and furthermore height and weight, skin test reactivity, lung function, and airway responsiveness were measured.

RESULTS

A total of 516 individuals had asthma. The mean BMI was 24.9 kg/m(2) (SD = 5.1). Asthma severity measured by GINA score increased with increasing BMI (p = 0.009). The result remained significant after adjusting for age, sex, medication use for asthma and smoking (p = 0.010). Severity of individual asthma symptoms; cough (p = 0.002) and chest tightness (p = 0.023) was also significantly related to BMI, whereas severity of wheezing and shortness of breath was not. Airway obstruction was more pronounced in subjects with increased BMI (p < 0.001) but the effect disappeared after adjustment for covariates (p = 0.233). Lung function, airway responsiveness, and atopy were not significantly related to BMI as were use of medication for asthma and adherence to treatment.

CONCLUSIONS

In adults, increased body mass index predicts severity of asthma symptoms but not objective asthma traits.

Adipose tissue content and distribution in children and adolescents with bronchial asthma

BACKGROUND

The excess of adipose tissue and the pattern of adipose tissue distribution in the body seem to play an important role in the complicated dependencies between obesity and risk of developing asthma. The aim of the present study was to determine nutritional status in children and adolescents with bronchial asthma with special emphasis on adipose tissue distribution evaluated on the basis of skin-fold thicknesses, and to determine the relationships between patterns of adipose tissue distribution and the course of the disease.

METHODS

Anthropometric data on height, weight, circumferences and skin-fold thicknesses were extracted from the medical histories of 261 children diagnosed with asthma bronchitis. Values for children with asthma were compared to Polish national growth reference charts. Distribution of subcutaneous adipose tissue was evaluated using principal components analysis (PCA). Multivariate linear regression analyses tested the effect of three factors on subcutaneous adipose tissue distribution: type of asthma, the severity of the disease and the duration of the disease.

RESULTS

Mean body height in the children examined in this study was lower than in their healthy peers. Mean BMI and skin-fold thicknesses were significantly higher and lean body mass was lower in the study group. Excess body fat was noted, especially in girls. Adipose tissue was preferentially deposited in the trunk in girls with severe asthma, as well as in those who had been suffering from asthma for a longer time. The type of asthma, atopic or non-atopic, had no observable effect on subcutaneous adipose tissue distribution in children examined.

CONCLUSIONS

The data suggest that long-treated subjects and those with severe bronchial asthma accumulate more adipose tissue on the trunk. It is important to regularly monitor nutritional status in children with asthma, especially in those receiving high doses of systemic or inhaled glucocorticosteroids, and long-term treatment as well.

Mediator effect of depressive symptoms on the association between BMI and asthma control in adults

BACKGROUND

Obesity has been associated with worse asthma control. Depression has also been shown to be disproportionally prevalent among patients with asthma and among patients with obesity. However, no studies have examined the mediating effect of depression on the obesity-asthma relationship. This study examined the extent to which depressive symptoms may mediate the obesity-asthma relationship in an adult sample.

METHODS

A total of 798 patients with physician-diagnosed asthma were recruited from the outpatient asthma clinic at Hôpital du Sacré-Cœur de Montréal. Patients provided demographic and medical history information and completed a battery of questionnaires, including the Beck Depression Inventory (BDI)-II and the Asthma Control Questionnaire (ACQ). BMI was calculated from self-reported height and weight.

RESULTS

Analyses adjusted for age, sex, years of education, cohabitation, and inhaled corticosteroid dose revealed an association between BMI and ACQ (β = 0.017, P = .026), between BMI and BDI-II (β = 0.189, P = .002), and between BDI-II and ACQ (β = 0.044, P < .001). However, when both BDI-II and BMI were entered into the same model, BDI-II (β = 0.044, P < .001) but not BMI (β = 0.009, P = .226) remained significantly associated with ACQ.

CONCLUSIONS

The results indicate that depression and a high BMI are both associated with worse asthma control. However, consistent with our hypotheses, the relationship between BMI and worse asthma control was mediated by depressive symptoms. Future studies should examine the precise role of depressive symptoms in both weight and asthma control.

Heterogeneity of phenotypes in severe asthmatics. The Belgian Severe Asthma Registry (BSAR)

The Belgian severe asthma registry is a web-based registry encompassing demographic, clinical, functional and inflammatory data of severe asthmatics (SA), aiming at improving awareness, knowledge on its natural history and subphenotypes, and offering tools to optimize care of this asthma population.

METHODS

The cross-sectional analyses of this registry included 350 SA as defined by the ATS (2000) from 9 Belgian centres, with at least one year follow up.

RESULTS

Mean age was 55 ± 14 yrs. SA were more frequently female (57%) and atopic (70%). Late-onset asthma (≥40 yr) was observed in 31% of SA. Current smokers represented 12% while 31% were ex-smokers. In addition to high doses ICS + LABA, 65% of patients were receiving LTRA, 27% anti-IgE and 24% maintenance oral corticosteroids (8 mg (Interquartile range-IQR:4-8) methylprednisolone). Despite impaired airflow (median FEV1:67%; IQR: 52-81) only 65% had a post-bronchodilator FEV1/FVC ratio <70%. The median blood eosinophil count was 240/mm³. The median FENO was 26 ppb (IQR: 15-43) and 22% of SA had FENO ≥ 50 ppb. Induced sputum was successful in 86 patients. Eosinophilic asthma (sputum Eos ≥ 3%) was the predominant phenotype (55%) while neutrophilic (sputum Neu ≥ 76%) and paucigranulocytic asthma accounted for 22% and 17% respectively. Comorbidities included rhinitis and chronic rhinosinusitis (49%), nasal polyposis (19%), oesophageal reflux (36%), overweight and obesity (47%) and depression (19%). In addition, 8% had aspirin-induced asthma and 3% ABPA. Asthma was not well-controlled in 83% according to ACT < 20 and 77% with ACQ > 1.5.

CONCLUSION

In this cohort of patients with severe asthma, the majority displayed indices of persistent airflow limitation and eosinophilic inflammation despite high-dose corticosteroids, suggesting potential for eosinophil-targeted biotherapies.

Complementing the randomized controlled trial evidence base. Evolution not revolution

Observational studies and pragmatic trials can complement classical randomized controlled trials (RCTs) by providing data more relevant to the circumstances under which medicine is routinely practiced, thereby providing practical guidance for clinicians. The bearing of RCT findings on day-to-day practice can be weighted and the data more meaningfully interpreted by practicing clinicians if evidence is integrated from a variety of different study designs and methodologies. The advent of observational studies and pragmatic trials, often referred to as "real-life studies," has met with a degree of cynicism, but their role and value is gaining widespread recognition and support among clinicians. This article discusses where observational studies and pragmatic trials have utility, namely: in addressing clinical questions that are unanswered and/or unanswerable by RCTs; in testing new hypotheses and possible license extensions; and in helping to differentiate between available therapies for a given indication. Moreover, it seeks to highlight how the different approaches fit within a conceptual framework of evidence relevant to clinical practice, a step-change in the traditional view of medical evidence.

Multiple chronic conditions and asthma: implications for practice and research

At least half of US adults with asthma have at least 1 other chronic condition. Having asthma and other chronic conditions are associated with poorer asthma outcomes. Several studies considered the relationship between asthma and other specific chronic conditions; results of these studies indicated that having depression or anxiety and/or panic disorder is associated with an increased risk of developing a new asthma diagnosis and with poorer asthma outcomes. In addition, results of these studies indicated that having asthma is associated with an increased risk of developing a new depression or anxiety and/or panic disorder diagnosis. Theoretical models for understanding multiple chronic conditions have emerged, with models that include a balance between patient workload and capacity; classification of specific conditions as concordant and/or discordant and/or dominant; and identification of the gap between what a patient needs and what health care services are able to offer. Potential implications for clinical providers include screening for chronic conditions not yet recognized, such as mental health disorders, promoting and tracking medication adherence in those who have multiple chronic conditions, and simplifying treatment regimens to reduce patient workload.

Respiratory tract infections and asthma control in children

INTRODUCTION

Asthma control is considered the major goal of asthma management, while many determinants of control are difficult to modify. We studied the association between respiratory infection episodes (RTIs) of various types and asthma control.

METHODS

Cross-sectional data were used from children aged 4-18 years with physician-diagnosed asthma who participated in a web-based electronic portal for children with asthma, allergies or infections. Asthma control was measured using the Childhood Asthma Control Test (C-ACT) or the Asthma Control Test (ACT). Linear regression was used to analyse the association between categories of numbers of various types of RTIs sustained in the preceding 12 months (categorized) and asthma control, adjusted for potential confounders.

RESULTS

Asthma control was assessed in 654 children, and 68.5% were clinically well controlled (ACT ≥ 20). Higher total numbers of RTIs in the last 12 months were strongly associated with a lower level of asthma control (p(trend) < 0.001). Similarly strong statistically significant associations were found for subtypes of RTI: ≥4 vs. 0 otitis episodes: coefficient -1.7 (95% CI -3.3 to -0.2); ≥5 vs.0 colds: coefficient -2.3 (95% CI -3.0 to -1.6); ≥3 vs. 0 bronchitis episodes: coefficient -3.1 (95% CI -4.0 to -2.3), each with p(trend) < 0.05.

CONCLUSION

Higher numbers of reported respiratory tract infections are associated with lower level of asthma control. The different type of respiratory tract infections contribute equally to less controlled asthma.

Obesity and symptoms of depression contribute independently to the poor asthma control of obesity

Obesity is a major risk factor for poorly controlled asthma, but the reasons for poor asthma control in this patient population are unclear. Symptoms of depression have been associated with poor asthma control, and increase with higher body mass index (BMI). The purpose of this study was to assess whether depressive symptoms underlie poor asthma control in obesity.

METHODS

We determined the relationship between BMI, psychological morbidity and asthma control at baseline in a well-characterized patient population participating in a clinical trial conducted by the American Lung Association-Asthma Clinical Research Centers.

RESULTS

Obese asthmatic participants had increased symptoms of depression (Center for Epidemiologic Studies Depression Scale score in lean 10.1 ± 8.1, overweight 10.0 ± 8.1, obese 12.4 ± 9.9; p = 0.03), worse asthma control (Juniper Asthma Control Questionnaire score in lean 1.43 ± 0.68, overweight 1.52 ± 0.71, obese 1.76 ± 0.75; p < 0.0001), and worse asthma quality of life (scores in lean 5.21 ± 1.08, overweight 5.08 ± 1.05, obese 4.64 ± 1.09; p < 0.0001). Asthmatics with obesity and those with symptoms of depression both had a higher risk of having poorly controlled asthma (adjusted odds ratio of 1.83 CI 1.23-3.52 for obesity, and 2.08 CI 1.23-3.52 for depression), but there was no interaction between the two.

CONCLUSION

Obesity and symptoms of depression are independently associated with poor asthma control. As depression is increased in obese asthmatics it may be an important co-morbidity contributing to poor asthma control in this population, but factors other than depression also contribute to poor asthma control in obesity.

Obesity and asthma in children: current and future therapeutic options

With the childhood prevalence of obesity and asthma increasing, it is important for pediatric professionals to appreciate that obesity modifies the diagnosis and management of asthma. These disease modifications present challenges to clinical management, including decreased responsiveness to controller therapy and decreased quality of life compared with normal-weight asthmatic children. While consensus guidelines do not currently suggest specific changes in asthma management for obese patients, management of some patients may be improved with consideration of the latest evidence. This article briefly summarizes what is known regarding the complex relationship between obesity and asthma in children, and discusses practical issues associated with the diagnosis and effective clinical management of asthma in obese children. On average, obese patients with asthma do not respond as well to inhaled corticosteroid therapy. Management approaches including weight loss and routine exercise are safe, and may improve important asthma outcomes. Asthma providers should learn to facilitate weight loss for their obese patients. In addition, pharmacologic interventions for weight loss in obese asthma, though not currently recommended, may soon be considered.

Predictors of perceived asthma control among patients managed in primary care clinics

OBJECTIVE

To estimate the extent to which symptom status, physical activity, beliefs about medications, self-efficacy, emotional status, and healthcare utilization predict perceived asthma control over a period of 16 months among a primary care population.

METHODS

The current study is a secondary analysis of data from a longitudinal study that examined health outcomes of asthma among participants recruited from primary care clinics. Path analysis, based on the Wilson and Cleary and International Classification of Functioning, Disability and Health frameworks, was used to estimate the predictors of perceived asthma control.

RESULTS

The path analysis identified initial perceived asthma control asthma (β = 0.43, p < 0.0001), symptoms (β = 0.35, p < 0.0001), physical activity (β = 0.27, p < 0.0001), and self-efficacy (β = 0.29, p < 0.0001) as significant predictors of perceived asthma control (total effects, i.e., direct and indirect), while emotional status (β = 0.08, p = 0.03) was a significant indirect predictor through physical activity. The model explained 24 % of the variance of perceived asthma control. Overall, the model fits the data well (χ (2) = 6.65, df = 6, p value = 0.35, root-mean-square error of approximation = 0.02, Comparative Fit Index = 0.999, and weighted root-mean-square residual = 0.27).

CONCLUSION

Initial perceived asthma control, current symptoms status, physical activity, and self-efficacy can be used to identify individuals likely to have good perceived asthma control in the future. Emotional status also has an impact on perceived asthma control mediated through physical activity and should be considered when planning patient management. Identifying these predictors is important to help the care team tailor interventions that will allow individuals to optimally manage their asthma, to prevent exacerbations, to prevent other respiratory-related chronic disease, and to maximize quality of life.

Does gender affect asthma control in adult asthmatics?

Several studies have shown gender differences in prevalence of asthma but there is little information about asthma control. In this study, we aimed to evaluate the effect of gender on asthma control in adult asthmatics. Medical records of 242 patients older than 18 years of age who regularly visited the allergy unit were evaluated. Standardized asthma questionnaires like the asthma control test (ACT) were performed. ACT scores, clinical characteristics, and demographic data such as smoking status, education, duration and severity of asthma, atopic status, family history of asthma, analgesic hypersensitivity, number of emergency visits, and hospitalization in the previous year were compared based on gender. In this study, 77.3% of the patients were female. Mean age, body mass index, and duration of asthma were 39.0 ± 0.7, 27.3 ± 0.3, and 6.6 ± 0.4 years, respectively. Of the total, 14.9% of the patients were smokers. Also, 55.8% of them were graduated from middle school, 22.7% from high school, and 14% from university. Atopy rate was 57%. Analgesic hypersensitivity was found in 18.6% of them. There was 30.2% family history of asthma. The asthma severity was mild in 45.5%, moderate in 40.9%, and severe in 13.6% of the patients. One-third of the patients were admitted to emergency room; 1/10th were hospitalized due to asthma in the previous year. ACT scores indicated complete control in 67.8%, partial control in 17.8%, and uncontrolled asthma in 14.5%. Comparing the results of males with females having asthma, there was no statistically significant difference between the two gender according to ACT scores and clinical characteristics. Finally, the results conclude that there was no effect of gender on asthma control assessed with standardized questionnaire in adult asthmatics.

Allergic disease is associated with epilepsy in childhood: a US population-based study

BACKGROUND

Previous studies using animal models suggest an association between allergic disease and epilepsy. We sought to determine whether allergic disease is associated with epilepsy in children.

METHODS

We used the 2007-2008 National Survey of Children's Health, a US population-based study of 91 642 children aged 0-17 years to determine the association between the prevalence of epilepsy and allergic disease, including asthma, atopic dermatitis (AD)/eczema, hay fever, and food allergies. Multivariate logistic regression models were constructed that controlled for confounding variables.

RESULTS

The US lifetime prevalence of childhood epilepsy was 1.03% and was significantly associated with older age, male sex, lower household income, family structure and history of brain injury or concussion. Children with ≥1 allergic disease had more epilepsy in their lifetime than nonallergic children (logistic regression, adjusted odds ratio [95% confidence interval] = 1.79 [1.37-2.33]). Lifetime prevalence (2.30 [1.50-3.52]) and one-year prevalence of asthma (2.00 [1.41-2.84]), AD/eczema (1.73 [1.17-2.56]), hay fever (1.93 [1.41-2.65]) and food allergies (2.69 [1.38-4.01]) were associated with increased odds of ever being diagnosed with epilepsy. Similar results were found for current history of epilepsy. Severe AD/eczema (3.89 [1.34-11.32]) [corrected] and hay fever (2.46 [1.11-5.41]) were associated with even higher odds of epilepsy compared with mild/moderate disease. As the number of allergic diseases increased, so did the odds of lifetime history and current history of epilepsy.

CONCLUSIONS

The US prevalence of epilepsy is associated with allergic diseases in children. Further studies are needed to determine whether allergic inflammation contributes toward epileptogenesis.

Clinical, economic, and humanistic burden of asthma in Canada: a systematic review

BACKGROUND

Asthma, one of the most common chronic respiratory diseases, affects about 3 million Canadians. The objective of this study is to provide a comprehensive evaluation of the published literature that reports on the clinical, economic, and humanistic burden of asthma in Canada.

METHODS

A search of the PubMed, EMBASE, and EMCare databases was conducted to identify original research published between 2000 and 2011 on the burden of asthma in Canada. Controlled vocabulary with "asthma" as the main search concept was used. Searches were limited to articles written in English, involving human subjects and restricted to Canada. Articles were selected for inclusion based on predefined criteria like appropriate study design, disease state, and outcome measures. Key data elements, including year and type of research, number of study subjects, characteristics of study population, outcomes evaluated, results, and overall conclusions of the study, were abstracted and tabulated.

RESULTS

Thirty-three of the 570 articles identified by the clinical and economic burden literature searches and 14 of the 309 articles identified by the humanistic burden literature searches met the requirements for inclusion in this review. The included studies highlighted the significant clinical burden of asthma and show high rates of healthcare resource utilization among asthma patients (hospitalizations, ED, physician visits, and prescription medication use). The economic burden is also high, with direct costs ranging from an average annual cost of $366 to $647 per patient and a total annual population-level cost ranging from ~ $46 million in British Columbia to ~ $141 million in Ontario. Indirect costs due to time loss from work, productivity loss, and functional impairment increase the overall burden. Although there is limited research on the humanistic burden of asthma, studies show a high (31%-50%) prevalence of psychological distress and diminished QoL among asthma patients relative to subjects without asthma.

CONCLUSIONS

As new therapies for asthma become available, economic evaluations and assessment of clinical and humanistic burden will become increasingly important. This report provides a comprehensive resource for health technology assessment that will assist decision making on asthma treatment selection and management guidelines in Canada.

Prevalence of obesity in asthma and its relations with asthma severity and control

OBJECTIVE: To determine the prevalence of obesity in asthmatic patients attending at an outpatient clinic, and to investigate its relationships with asthma severity and level of asthma control. METHODS: In a cross-sectional study we recruited patients aged 11 years and older with confirmed asthma diagnosis from the outpatient asthma clinic of Hospital de Clínicas de Porto Alegre, Brazil. They underwent an evaluation by a general questionnaire, an asthma control questionnaire and by pulmonary function tests. Nutritional status was classified by body mass index (BMI). RESULTS: 272 patients were included in the study. Mean age was 51.1 ± 16.5 years and there were 206 (74.9%) female patients. Mean BMI was 27.5 ± 5.3 kg/m², and 96 (35.3%) patients were classified as normal weight, 97 (35.7%) as overweight and 79 (29%) as obesity. There was a significant higher proportion of female than male patients (34.3% vs. 13.2%, p = 0.002) in the obesity group. There were no significant differences with respect to asthma control (p = 0.741) and severity classification (p = 0.506). The FEV1% predicted was significantly higher in the obese than in the non-obese group (73.7% vs. 67.2%, p = 0.037). Logistic regression analysis identified sex (OR = 3.84, p = 0.002) as an independent factor associated with obesity. CONCLUSIONS: This study showed a high prevalence of obesity in asthmatic patients. Obese and non-obese subjects were similar in regard to asthma severity and level of asthma control. Female sex was associated with obesity in this asthma population.

Prevalence of obesity in asthma and its relations with asthma severity and control

OBJECTIVE

To determine the prevalence of obesity in asthmatic patients attending at an outpatient clinic, and to investigate its relationships with asthma severity and level of asthma control.

METHODS

In a cross-sectional study we recruited patients aged 11 years and older with confirmed asthma diagnosis from the outpatient asthma clinic of Hospital de Clínicas de Porto Alegre, Brazil. They underwent an evaluation by a general questionnaire, an asthma control questionnaire and by pulmonary function tests. Nutritional status was classified by body mass index (BMI).

RESULTS

272 patients were included in the study. Mean age was 51.1 ± 16.5 years and there were 206 (74.9%) female patients. Mean BMI was 27.5 ± 5.3kg/m(2), and 96 (35.3%) patients were classified as normal weight, 97 (35.7%) as overweight and 79 (29%) as obesity. There was a significant higher proportion of female than male patients (34.3% vs. 13.2%, p = 0.002) in the obesity group. There were no significant differences with respect to asthma control (p = 0.741) and severity classification (p = 0.506). The FEV1% predicted was significantly higher in the obese than in the non-obese group (73.7% vs. 67.2%, p = 0.037). Logistic regression analysis identified sex (OR = 3.84, p = 0.002) as an independent factor associated with obesity.

CONCLUSIONS

This study showed a high prevalence of obesity in asthmatic patients. Obese and non-obese subjects were similar in regard to asthma severity and level of asthma control. Female sex was associated with obesity in this asthma population.

Immunometabolism in obese asthmatics: are we there yet?

Obesity is now recognised as a worldwide epidemic. The recent International Association for the Study of Obesity/International Obesity Taskforce (IASO/IOTF) analysis estimates that approximately 1.0 billion adults are currently overweight and a further 475 million are obese. Obesity has huge psychosocial impact with obese children and adolescents facing discrimination and stigmatization in many areas of their lives leading to body dissatisfaction, low self-esteem and depression. Indeed, obesity is recognised as an important risk factor for the development of several chronic diseases such as hypertension, cancer, asthma and metabolic syndrome. Chronic low grade systemic inflammation is considered as a hallmark of obesity and may possibly explain the link between obesity and chronic disease, in particular the increased incidence, prevalence and severity of asthma in obese individuals. There is now strong evidence for infiltration of immune and inflammatory cells into adipose tissue that drives systemic inflammation and subsequent end organ damage. In addition to adipocytes, the key adipose tissue resident immune cells are macrophages and mast cells. Immunometabolism, as an emerging field of investigation, explores the pivotal role of these immune cells in translating immunological changes to metabolic effects in obesity. Abundance of free fatty acids, along with other inflammatory cytokines shift the balance of metabolic homeostasis to pro-inflammatory status by influencing the development of inflammatory cell lineage, which, further exhibits distinct functional phenotypes. There is emerging evidence for macrophage activation and functional polarization of an anti-inflammatory M₂ phenotype towards a pro-inflammatory M₁ phenotype of macrophages in obese adipose tissue. Similarly, studies in both obese humans and murine models reveal the pathognomic presence of an increased number of mast cells in visceral adipose tissue. These suggest a possible contribution of mast cells to the unique metabolome of obese asthma. This review examines proposed multilevel interactions between metabolic and immune systems in obese asthmatics that underlie the negative effects of obesity and may offer significant therapeutic promise.

Impact of obesity on perinatal outcomes among asthmatic women

BACKGROUND

Only one study has investigated the combined effect of maternal asthma and obesity on perinatal outcomes; however, it did not consider small-for-gestational age and large-for-gestational age infants.

OBJECTIVES

To examine the impact of obesity on perinatal outcomes among asthmatic women.

METHODS

A cohort of 1386 pregnancies from asthmatic women was reconstructed using three of Quebec's administrative databases and a questionnaire. Women were categorized using their prepregnancy body mass index. Underweight, overweight and obese women were compared with normal weight women. The primary outcome was the birth of a small-for-gestational-age infant, defined as a birth weight below the 10th percentile for gestational age and sex. Secondary outcomes were large-for-gestational-age infants (birth weight >90th percentile for gestational age) and preterm birth (<37 weeks' gestation). Logistic regression models were used to obtain the ORs of having small-for-gestational-age infants, large-for-gestational-age infants and preterm birth as a function of body mass index.

RESULTS

The proportions of underweight, normal weight, overweight and obese women were 10.8%, 53.3%, 19.7% and 16.2%, respectively. Obese asthmatic women were not found to be significantly more at risk for giving birth to small-for-gestational-age infants (OR 0.6 [95% CI 0.4 to 1.1]), large-for-gestational-age infants (OR 1.2 [95% CI 0.7 to 2.2]) or having a preterm delivery (OR 0.7 [95% CI 0.4 to 1.3]) than normal-weight asthmatic women.

CONCLUSIONS

No significant negative interaction between maternal asthma and obesity on adverse perinatal outcomes was observed.

Leptin as regulator of pulmonary immune responses: involvement in respiratory diseases

Leptin is an adipocyte-derived hormone, recognized as a critical mediator of the balance between food intake and energy expenditure by signalling through its functional receptor (Ob-Rb) in the hypothalamus. Structurally, leptin belongs to the long-chain helical cytokine family, and is now known to have pleiotropic functions in both innate and adaptive immunity. The presence of the functional leptin receptor in the lung together with evidence of increased airspace leptin levels arising during pulmonary inflammation, suggests an important role for leptin in lung development, respiratory immune responses and eventually pathogenesis of inflammatory respiratory diseases. The purpose of this article is to review our current understanding of leptin and its functional role on the different resident cell types of the lung in health as well as in the context of three major respiratory conditions being chronic obstructive pulmonary disease (COPD), asthma, and pneumonia.

Asthma and obesity

The prevalence and incidence of asthma have increased among obese children and adults, particularly among women. Obesity seems to be a predisposing factor for the development of asthma, but the underlying mechanisms of its influence are still uncertain. Various hypotheses have been proposed to explain the link between obesity and asthma such as a common genetic predisposition, developmental changes, altered lung mechanics, the presence of a systemic inflammatory process, and an increased prevalence of associated comorbid conditions. Over-diagnosis of asthma does not seem to be more frequent in obese compared to non-obese subjects, but the added effects of obesity on respiratory symptoms can affect asthma control assessment. Obesity can make asthma more difficult to control and is associated with a reduced beneficial effect of asthma medications. This could be due to a change in asthma phenotype, particularly evidenced as a less eosinophilic type of airway inflammation combined to the added effects of changes in lung mechanics. Weight loss is associated with a universal improvement of asthma and should be part of asthma management in the obese patient. Additional research should be conducted to better determine how obesity influences the development and clinical expression of asthma, establish the optimal management of asthma in this population and determine how obesity affects long-term asthma outcomes in these patients.

The effects of a multisite aerobic exercise intervention on asthma morbidity in sedentary adults with asthma: the Ex-asthma study randomised controlled trial protocol

OBJECTIVE

Aerobic exercise can improve cardiovascular fitness and does not seem to be detrimental to patients with asthma, though its role in changing asthma control and inflammatory profiles is unclear. The main hypothesis of the current randomised controlled trial is that aerobic exercise will be superior to usual care in improving asthma control. Key secondary outcomes are asthma quality of life and inflammatory profiles.

DESIGN

A total of 104 sedentary adults with physician-diagnosed asthma will be recruited. Eligible participants will undergo a series of baseline assessments including: the asthma control questionnaire; the asthma quality-of-life questionnaire and the inflammatory profile (assessed from both the blood and sputum samples). On completion of the assessments, participants will be randomised (1:1 allocation) to either 12-weeks of usual care or usual care plus aerobic exercise. Aerobic exercise will consist of three supervised training sessions per week. Each session will consist of taking a short-acting bronchodilator, 10 min of warm-up, 40 min of aerobic exercise (50-75% of heart rate reserve for weeks 1-4, then 70-85% for weeks 5-12) and a 10 min cool-down. Within 1 week of completion, participants will be reassessed (same battery as at baseline). Analyses will assess the difference between the two intervention arms on postintervention levels of asthma control, quality of life and inflammation, adjusting for age, baseline inhaled corticosteroid prescription, body weight change and pretreatment dependent variable level. Missing data will be handled using standard multiple imputation techniques.

ETHICS AND DISSEMINATION

The study has been approved by all relevant research ethics boards. Written consent will be obtained from all participants who will be able to withdraw at any time.

RESULTS

The result will be disseminated to three groups of stakeholder groups: (1) the scientific and professional community; (2) the research participants and (3) the general public.

REGISTRATION DETAILS CLINICALTRIALSGOV IDENTIFIER

NCT00953342.

Impact of adiponectin overexpression on allergic airways responses in mice

Obesity is an important risk factor for asthma. Obese individuals have decreased circulating adiponectin, an adipose-derived hormone with anti-inflammatory properties. We hypothesized that transgenic overexpression of adiponectin would attenuate allergic airways inflammation and mucous hyperplasia in mice. To test this hypothesis, we used mice overexpressing adiponectin (Adipo Tg). Adipo Tg mice had marked increases in both serum adiponectin and bronchoalveolar lavage (BAL) fluid adiponectin. Both acute and chronic ovalbumin (OVA) sensitization and challenge protocols were used. In both protocols, OVA-induced increases in total BAL cells were attenuated in Adipo Tg versus WT mice. In the acute protocol, OVA-induced increases in several IL-13 dependent genes were attenuated in Adipo Tg versus WT mice, even though IL-13 per se was not affected. With chronic exposure, though OVA-induced increases in goblet cells numbers per millimeter of basement membrane were greater in Adipo Tg versus WT mice, mRNA abundance of mucous genes in lungs was not different. Also, adiponectin overexpression did not induce M2 polarization in alveolar macrophages. Our results indicate that adiponectin protects against allergen-induced inflammatory cell recruitment to the airspaces, but not development of goblet cell hyperplasia.

Childhood obesity and asthma control in the GALA II and SAGE II studies

RATIONALE

Obesity is associated with increased asthma morbidity, lower drug responsiveness to inhaled corticosteroids, and worse asthma control. However, most prior investigations on obesity and asthma control have not focused on pediatric populations, considered environmental exposures, or included minority children.

OBJECTIVES

To examine the association between body mass index categories and asthma control among boys and girls; and whether these associations are modified by age and race/ethnicity.

METHODS

Children and adolescents ages 8-19 years (n = 2,174) with asthma were recruited from the Genes-environments and Admixture in Latino Americans (GALA II) Study and the Study of African Americans, Asthma, Genes, and Environments (SAGE II). Ordinal logistic regression was used to estimate odds ratios (OR) and their confidence intervals (95% CI) for worse asthma control.

MEASUREMENTS AND MAIN RESULTS

In adjusted analyses, boys who were obese had a 33% greater chance of having worse asthma control than their normal-weight counterparts (OR, 1.33; 95% CI, 1.04-1.71). However, for girls this association varied with race and ethnicity (P interaction = 0.008). When compared with their normal-weight counterparts, obese African American girls (OR, 0.65; 95% CI, 0.41-1.05) were more likely to have better controlled asthma, whereas Mexican American girls had a 1.91 (95% CI, 1.12-3.28) greater odds of worse asthma control.

CONCLUSIONS

Worse asthma control is uniformly associated with increased body mass index in boys. Among girls, the direction of this association varied with race/ethnicity.

Role of obesity in asthma control, the obesity-asthma phenotype

Asthma is a disease with distinct phenotypes that have implications for both prognosis and therapy. Epidemiologic studies have demonstrated an association between asthma and obesity. Further studies have shown that obese asthmatics have poor asthma control and more severe asthma. This obese-asthma group may represent a unique phenotype. The mechanisms behind poor asthma control in obese subjects remain unclear, but recent research has focused on adipokines and their effects on the airways as well as the role of oxidative stress. Both surgical and nonsurgical weight loss therapy have shown promising results with improvements in asthma control and decreased asthma severity. Comorbid conditions such as gastroesophageal reflux disease and obstructive sleep apnea may also have a role in poor asthma control in obese asthmatics. Further research is needed to define the mechanisms behind this phenotype which will guide the development of targeted therapies.

Pediatric obesity and asthma quality of life

Widely researched as separate entities, our understanding of the comorbid effects of childhood obesity and asthma on quality of life is limited. This article discusses the effects of childhood obesity and asthma on self-reported quality of life in low-income African American teens with asthma. When controlling for the influence of symptom frequency, asthma classification, asthma self-efficacy, and asthma self-care levels, body mass index remains a most important factor in determining self-reported quality of life among teens with asthma. Although overweight and obesity did not change the effectiveness of the asthma intervention program, obesity did affect participants quality of life scores.

Do mast cells link obesity and asthma?

Asthma is a chronic inflammatory disease of the lungs. Both the number of cases and severity of asthma have been increasing without a clear explanation. Recent evidence suggests that obesity, which has also been increasing alarmingly, may worsen or precipitate asthma, but there is little evidence of how obesity may contribute to lung inflammation. We propose that mast cells are involved in both asthma and obesity by being the target and source of adipocytokines, 'alarmins' such as interleukin-9 (IL-9) and interleukin-33 (IL-33), and stress molecules including corticotropin-releasing hormone (CRH) and neurotensin (NT), secreted in response to the metabolic burden. In particular, CRH and NT have synergistic effects on mast cell secretion of vascular endothelial growth factor (VEGF). IL-33 augments VEGF release induced by substance P (SP) and tumor necrosis factor (TNF) release induced by NT. Both IL-9 and IL-33 also promote lung mast cell infiltration and augment allergic inflammation. These molecules are also expressed in human mast cells leading to autocrine effects. Obese patients are also less sensitive to glucocorticoids and bronchodilators. Development of effective mast cell inhibitors may be a novel approach for the management of both asthma and obesity. Certain flavonoid combinations may be a promising new treatment approach.

Central obesity and asthma outcomes in adults diagnosed with asthma

OBJECTIVE

The potential role of central obesity in asthma outcomes has been examined in a few studies. The aim of this study was to examine the relationship between central obesity and asthma outcomes in a group of Iranian asthma patients.

METHODS

One hundred and forty-two outpatients with asthma were studied. Central obesity was defined according to National Institute of Health (NIH) and Asian waist circumference (WC) and waist-to-hip ratio (WHR) cut-offs. Asthma outcomes including asthma control, pulmonary function, and morbidity were evaluated. The association between central obesity and asthma outcomes was studied by linear and logistic regression analyses.

RESULTS

Linear regression analysis showed a significant association of WHR-based central obesity with forced expiratory volume in 1 s (FEV(1)) (β = -9.04; p-value = .044) and forced vital capacity (FVC) (β = -10.52; p-value = .012). Logistic regression analysis showed a significant increased risk of asthma attacks in 3 months with Asian WC-based central obesity [odds ratio (OR) = 6.31, 95% confidence interval (CI): 1.16-34.41]; emergency room (ER) visits with NIH WC-based (OR = 5.15, 95% CI: 1.36-19.55) and Asian WC-based (OR = 18.72, 95% CI: 1.92-182.63) central obesity; and hospitalization in 1 year with NIH WC-based (OR = 5.28, 95% CI: 1.28-21.84) and Asian WC-based (OR = 12.39, 95% CI: 1.29-119.53) central obesity.

CONCLUSIONS

Our study shows that the Asian WC-based central obesity is a better predictor of asthma morbidity. The results of this study emphasize, when studying the relationship between asthma control and obesity, the importance of selecting the proper definitions for asthma control or central obesity and appropriate cutpoints. Further study in this field using other asthma control and quality of life questionnaires is warranted.

Statins as potential therapeutic drug for asthma?

Background

Statins are lipid-lowering agents that also exhibit pleiotropic effects in decreasing oxidative stress and inflammation. There have been several published studies reporting the use of statins in the treatment of asthma patients, but their results are not consistent. The aim of this study is to determine whether statins are beneficial for asthma administration, and explore the potential covariables that may affect their clinical effectiveness.

Methods

A systematic literature search was performed in PubMed, Embase and Cochrane Center Register of Controlled Trials from inception to September 2012. Randomized controlled trials (RCT), retrospective studies and controlled clinical trials which reported the use of statins in the treatment of asthma patients were eligible. Quality evaluation was conducted for RCT using Jadad criteria.

Results

A total of 18 articles were included. In our study, we found no conclusive evidence to demonstrate that statins could enhance the lung function in asthmatics, although, they may reduce airway inflammation. Additionally, the results were not consistent across studies with respect to symptoms, quality of life, maintenance medication, asthma hospitalization/emergency department (ED) visits.

Conclusions

Statins may reduce airway inflammation in asthmatics, without having a significant effect on lung function. Further large sample and multicenter clinical trials are needed to confirm this and to see if there are more responsive phenotypes of asthma.

The treatment of asthma in obesity

The world is facing an unprecedented epidemic of obesity. This epidemic has led to major changes in the epidemiology of common diseases such as asthma. Obesity is a major risk factor for new-onset asthma. This article will discuss the role of mechanical and metabolic factors, as well as obesity-related comorbidities, in both causing airway disease and also affecting response to therapy in obese asthmatics. Asthma in obese individuals probably includes a spectrum of disease with at least two distinct phenotypes: early-onset allergic disease complicated by obesity and late-onset disease developing in the setting of obesity. Both phenotypes are distinct from asthma in lean individuals. Treatment of asthma in obesity needs to consider altered response to controller therapy, and the fact that mechanical factors, metabolic inflammation and other comorbidities are probably contributing to airway disease. Future studies should focus on the development of therapies specifically tailored towards the treatment of asthma in obesity.

Sex Differences in the Effects of Inhaled Corticosteroids on Weight Gain among Patients with Asthma

Background. Studies have shown that asthma and asthma exacerbations are related to body weight and that this relationship might be sex-specific. While oral corticosteroids have been associated with weight gain, little is known about the effect of inhaled corticosteroid (ICS) use on short-term weight gain. The purpose of the present study was to examine whether ICSs would be associated with weight gain among asthmatic patients. Methods. A total of 180 adult patients with physician-diagnosed asthma provided details of their medical history and demographic information, along with height and weight at baseline and at one year. Weight change was defined as follow-up minus baseline weight. General linear models were used to assess the relationship between ICS dose (fluticasone propionate equivalent) and sex. Results. Significant main effects of sex (P=.005) and ICS dose (P=.036) and an interaction effect of sex and ICS dose (P=.003) on weight change were observed. Further analysis of the interaction indicated that women had greater weight gain, while men had decreased weight with increased ICS dose. Conclusions. Findings suggest that ICSs may trigger weight gain in females and highlight the need for studies to confirm this relationship and examine the potential underlying mechanisms.

Predictors of asthma control: what can we modify?

PURPOSE OF REVIEW

One strategy to improve asthma control is to identify risk factors for uncontrolled asthma in epidemiologic studies and then consider those risk factors as potential targets for intervention. This article reviews predictors of impairment based on validated tools and predictors of severe asthma exacerbations.

RECENT FINDINGS

Indirectly modifiable risk factors for poor asthma control include older age in adults, lower socioeconomic status, and poor perception of dyspnea. Modifiable risk factors for poor asthma control include allergy triggers, low adherence, comorbidities, absence of specialty care, and various aspects of asthma self-management education.

SUMMARY

Intervention strategies are suggested for predictors that are directly or indirectly modifiable. It is hoped that attention to these factors will improve asthma control and reduce the burden of disease.

Weight loss interventions for chronic asthma

BACKGROUND

Asthma and obesity are both public health problems with increasing prevalence globally. Several epidemiological studies have shown an association between asthma and obesity, however there is no good quality evidence on the effect of weight loss on asthma control.

OBJECTIVES

To assess the effect of various interventions for weight loss on measures of asthma control and weight loss amongst overweight or obese patients with chronic asthma.

SEARCH METHODS

We searched the Cochrane Airways Group's Specialized Register of Trials (CAGR) (derived from systematic searches of bibliographic databases, including the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE, CINAHL, AMED and PsycINFO, and handsearching of respiratory journals and meeting abstracts). We also searched ongoing trials web sites and dissertation databases up to March 2012. We contacted experts in the field and searched reference lists for additional studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of weight loss interventions for overweight or obese participants with asthma compared to either no intervention for weight loss or an alternative weight loss intervention.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility and risk of bias, and extracted data using a data extraction form. We did not undertake any meta-analysis as there were no suitable data to combine.

MAIN RESULTS

We included four completed studies conducted amongst adults (n = 197). Two were published as abstracts, and two as full articles. Interventions included supervised physical activity, low calorie diet and anti-obesity drugs (singly or in combination), and were compared to usual care (two studies), low calorie diet (one study), while one study had three intervention arms (physical activity versus low calorie diet versus a combination of the two). Two studies were conducted in high-income countries, while two were conducted in upper, middle-income countries.All studies had an unclear risk of selection and a high risk of detection bias. One of the studies found a statistically significant reduction in symptoms scores in treatment compared to control groups: the difference between groups in total St. George's Respiratory Questionnaire (SGRQ) score was -10 units (95% CI -18 to-1; P = 0.02). One study showed reduction in doses of rescue medication in treatment compared with control groups in the short term. Weight loss was associated with some improvement in forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) in one study, which was statistically significant, but clinically unimportant; there was no improvement in peak expiratory flow rate (PEFR). No data were reported on health care utilization and adverse effects. One study reported statistically significant weight loss in the treatment group compared to controls with no intervention, which was still significant at one year follow-up.

AUTHORS' CONCLUSIONS

Implications for practice This review found one randomized trial that showed that weight loss may be beneficial for improving asthma control in overweight and obese patients, in conjunction with weight loss in intervention groups in the short term. Applying the GRADE system to the results of this review however, shows that the quality of evidence is low, because although all four studies are RCTs there were serious methodological limitations in the studies (unclear risk of selection bias and high risk of detection bias) and imprecision (small sample size). There is inadequate evidence to comment on the effect of weight loss interventions on quality of life and health care utilization. In addition, there was inadequate reporting of data on adverse effects to permit proper balancing of harms and benefits of the interventions. On account of this low quality of evidence, the benefit of weight loss as an intervention for asthma control remains uncertain, and as such, clinicians should be prepared to help patients to make a decision that is consistent with their own values.Implications for research The finding that most of the included studies were of low methodological quality highlights the need for further well designed RCTs, with emphasis on adequate methods of allocation sequence generation as well as allocation concealment and longer follow-up periods. These studies need to report more fully on relevant outcomes (both statistically significant and otherwise) such as: asthma symptoms/control, use of rescue medication, change in lung function parameters (actual mean/median values), hospital utilization, quality of life, and adverse effects. There is also a need for longer intervention as well as follow-up durations to evaluate the effect of sustained measures to achieve weight loss, and to determine if these effects are still significantly present after a considerable period of time.There is also a need for these well designed studies in children and adolescents, as well as in low-income countries such as Africa, where the prepackaged, low energy diets, as well as structured physical activity-based interventions utilized in these included studies, may not be feasible or applicable.

Obesity, Nutrition, and Asthma in Children

Obesity rates have increased dramatically among children in many parts of the world, especially in North America and several other English-speaking countries. The impact of obesity on pediatric health has become a major prevention initiative by the Obama administration and several public health organizations. Children with obesity are at increased risk for developing asthma, which is already one of the most common chronic diseases among children. The cause underlying obesity's impact on asthma risk is unknown. Commonly cited potential etiologies include airway smooth muscle dysfunction from thoracic restriction, obesity-related circulating inflammation priming the lung, and obesity-related comorbidities mediating asthma symptom development. Each of these theories does not fit precisely with all of the data that have accumulated over the last decade. In this review, I will explore other possible causes including: (1) dietary characteristics common in Westernized countries that might lead to both obesity and asthma; (2) reductions in physical activity; and (3) genetic alterations that increase the propensity to both obesity and asthma together. Next, I will review the current data on how obesity affects common characteristics of asthma such as airway inflammation, lung function, risk of exacerbation, atopy, and response to treatment. Obesity in children with asthma appears to be associated with greater airflow obstruction and a mildly diminished response to inhaled corticosteroids. Little objective evidence in children suggests that obesity significantly heightens the risk of exacerbation or worsens disease stability in children. Lastly, I will discuss the current literature that suggests that obese children with asthma generally should receive the same guidelines-based management as lean children. However, interventions that encourage daily physical activity, weight-loss, normalization of nutrient levels, and monitoring of common obesity-related sequelae should be considered by healthcare providers managing obese children with difficult-to-control asthma.

Obesity, expiratory flow limitation and asthma symptoms

Obesity is associated with poor asthma control, but the reason for this is unclear. Reduction in operating lung volume, as occurs in obesity, and bronchoconstriction, as occurs in asthma, can increase expiratory flow limitation during tidal breathing (EFLt), which may in turn increase respiratory symptoms. The aim of this study was to determine the effect of obesity on EFLt at baseline and after bronchoconstriction in non-asthmatic and asthmatic subjects, and to determine the association between EFLt, and respiratory symptoms. Data from previously published studies in non-asthmatic and asthmatic subjects were reanalyzed using an index of EFLt derived from respiratory system reactance measured by the forced oscillation technique. The analysis showed that during bronchoconstriction both non-asthmatic and asthmatic obese individuals were more likely to develop EFLt than non-obese subjects, despite similar changes in FEV1. Furthermore the index of EFLt was a significant determinant of the severity of breathlessness during challenge in non-asthmatic subjects, and of asthma symptom control in asthmatic subjects following anti-inflammatory treatment. These studies suggest that the combination of bronchoconstriction and low resting lung volume increase the risk of EFLt, and that this altered response to bronchoconstriction may increase the severity of symptoms and lead to worse asthma control.

Patient, practice and organisational influences on asthma control: observational data from a national study on primary care in the United Kingdom

BACKGROUND

Achieving asthma control is central to optimising patient quality of life and clinical outcome. Contemporary models of chronic disease management across a variety of countries point to the importance of micro, meso and macro level influences on patient care and outcome. However, asthma outcomes research has almost invariably concentrated on identifying and addressing patient predictors. Little is known about higher level organisational influences.

OBJECTIVE

This paper explores the contribution of organisational factors on poor asthma control, allowing for patient factors, at three organisational levels: the individual patient, local service deliverers, and strategic regional providers.

DESIGN, SETTING AND PARTICIPANTS

Prospective cross-sectional observational cohort study of 64,929 people with asthma from 1205 primary care practices spread throughout the United Kingdom (UK). Patient clinical data were recorded during a routine asthma review.

METHOD

Data were analysed using simple descriptive, multiple regression and complex multi-level modelling techniques, accounting for practice clustering of patients.

RESULTS

Poor asthma control was associated with areas of higher deprivation [regression coefficient 0.026 (95% confidence intervals 0.006; 0.046)] and urban practice [-0.155 (-0.275; -0.035)] but not all local and regional variation was explained by the data. In contrast, patient level predictors of poor control were: short acting bronchodilator overuse [2.129 (2.091; 2.164)], days-off due to asthma [1.203 (1.148; 1.258)], PEFR<80 [0.76 (0.666; 0.854)], non-use of a self-management plan (SMP) [0.554 (0.515; 0.593)], poor inhaler technique [0.53 (0.475; 0.585)], poor medication compliance [0.385 (-0.007; 0.777)], and gender [0.314 (0.281; 0.347)]. Pattern of medication use, smoking history, age, body mass index (BMI), and health service resource use were also significant factors for predicting control.

CONCLUSIONS

Targeting of health service resource requires knowledge of the factors associated with poor control of asthma symptoms. In the UK the contribution of local and regional structures appears minimal in explaining variation in asthma outcomes. However, unexplained variation in the data suggests other unrecorded factors may play a part. While patient personal characteristics (including self-management plan use, inhaler technique, medication compliance) appear to be the predominant influence the complex nature of the disease means that some, perhaps more subtle, influences are affecting the variability at all levels and this variance needs to be explored. Further research in other international contexts is required to identify the likely applicability of these findings to other health care systems.

Asthma outcomes: quality of life

BACKGROUND

"Asthma-related quality of life" (QOL) refers to the perceived impact that asthma has on the patient's QOL.

OBJECTIVE

National Institutes of Health institutes and other federal agencies convened an expert group to recommend standardized measures of the impact of asthma on QOL for use in future asthma clinical research.

METHODS

We reviewed published documentation regarding the development and psychometric evaluation; clinical research use since 2000; and extent to which the content of each existing QOL instrument provides a unique, reliable, and valid assessment of the intended construct. We classified instruments as core (required in future studies), supplemental (used according to the study's aims and standardized), or emerging (requiring validation and standardization). This work was discussed at an National Institutes of Health-organized workshop convened in March 2010 and finalized in September 2011.

RESULTS

Eleven instruments for adults and 6 for children were identified for review. None qualified as core instruments because they predominantly measured indicators of asthma control (symptoms and/or functional status); failed to provide a distinct, reliable score measuring all key dimensions of the intended construct; and/or lacked adequate psychometric data.

CONCLUSIONS

In the absence of existing instruments that meet the stated criteria, currently available instruments are classified as either supplemental or emerging. Research is strongly recommended to develop and evaluate instruments that provide a distinct, reliable measure of the patient's perception of the impact of asthma on all of the key dimensions of QOL, an important outcome that is not captured in other outcome measures.

Individual and combined impact of cigarette smoking, anxiety, and mood disorders on asthma control

INTRODUCTION

Despite the availability of effective therapies, research indicates that more than 50% of asthmatics are poorly controlled. Poor asthma control has been linked to behavioral (i.e., cigarette smoking) and psychological factors (i.e., anxiety and depression). However, little is known about the individual versus combined impact of cigarette smoking and anxiety or mood disorders in adult asthmatics on asthma control.

METHODS

A total of 796 confirmed adult asthma patients completed a sociodemographic and medical history interview and underwent a psychiatric interview using the Primary Care Evaluation of Mental Disorders. Asthma control was evaluated using the Asthma Control Questionnaire.

RESULTS

After adjusting for age, sex, and dose of inhaled corticosteroids, general linear model analyses indicated a significant main effect of current smoking on asthma control (B [SE] = 0.156 [0.059], p = .008) and main effects of anxiety disorders (B [SE] = 0.408 [0.095], p = < .001) and mood disorders (B [SE] = 0.448 [0.098], p = < .001) on asthma control. Pack-years were not associated with asthma control, and there were no interaction effects of current smoking or pack-years with either anxiety or mood disorders on asthma control.

CONCLUSIONS

Findings suggest that current smoking, having an anxiety disorder, and having a mood disorder are independently associated with poorer asthma control but that cumulative smoking history (i.e., pack-years) was not associated with worse asthma control. These results indicate that smoking cessation may have a positive impact on asthma control levels in spite of past smoking intensity and highlight the importance of interventions that target anxiety and mood disorders in adult asthmatics.

Budesonide/formoterol pressurized metered-dose inhaler versus budesonide: a randomized controlled trial in black patients with asthma

OBJECTIVE

Concerns exist that responses to long-acting β(2)-adrenergic agonists in black patients may differ from the general population. The efficacy and safety of budesonide/formoterol (BUD/FM) pressurized metered-dose inhaler (pMDI) versus budesonide dry powder inhaler (BUD DPI) were evaluated in adolescent and adult black asthma patients.

METHODS

This 12-week, randomized, double-blind, multicenter, phase IV US study was conducted in 311 self-reported black patients aged ≥12 years with moderate to severe persistent asthma, previously receiving medium- to high-dose inhaled corticosteroid. After 2 weeks on BUD 90 μg × 2 inhalations twice daily (bid), symptomatic patients were randomized to BUD/FM 160/4.5 μg × 2 inhalations bid or BUD 180 μg × 2 inhalations bid.

RESULTS

Improvement in predose forced expiratory volume in 1 second from baseline to the treatment mean (primary variable) was greater with BUD/FM versus BUD (0.16 vs. 0.07 L; p = .008); this effect was also observed at weeks 2, 6, and end of treatment (p ≤ .032). Greater improvements (p < .001) in peak expiratory flow with BUD/FM versus BUD were seen at first measurement and maintained during 12 weeks (morning: 25.34 vs. 7.53 L/minute, respectively; evening: 21.61 vs. 7.67 L/minute, respectively); greater improvements in daily asthma symptom score and rescue medication use were also observed (p ≤ .039). Both treatments were well tolerated, with similar safety profiles.

CONCLUSIONS

In this population of black asthma patients, BUD/FM pMDI resulted in greater improvements in pulmonary function and asthma control versus BUD DPI, with similar safety profiles.