Long-term prognosis of new adult-onset asthma in obese patients

Weight-adjusted waist index is an independent predictor of all-cause and cause-specific mortality in patients with asthma

BACKGROUND

There is a close relationship between obesity and the occurrence of asthma.The weight-adjusted waist index (WWI) is a relatively novel anthropometric parameter that reflects obesity.

OBJECTIVE

We aimed to explore the association between WWI and mortality in the asthma population.

METHODS

We included adult with asthma from NHANES 1999-2018. WWI = Waist circumference (cm)/square root of body weight (kg). Current asthma was determined by the participant's responses in standardized questionnaires. All-cause, cardiovascular disease (CVD), cancer, and respiratory disease mortality information was obtained by prospectively matching these data to the National Death Index. Multivariate-adjusted Cox proportional hazards regression analyses, Kaplan Meier survival analyses, restricted cubic spline (RCS) analyses, stratified analyses, and sensitivity analyses were used to clarify these associations.

RESULTS

A total of 101,316 participants were included in the study, and 3223 were diagnosed with asthma.WWI was independently and positively associated with all-cause and all factor-specific mortality in asthma. In fully adjusted models, each unit increase in WWI was associated with 43 % (hazard ratio [HR] and 95 % confidence interval [CI] = 1.43 [1.25,1.64], p < 0.0001), 58 % (1.58 [1.25, 1.99], p < 0.001), 50 % (1.50 [1.19, 1.90], p < 0.001), and 79 % (1.79 [1.34, 2.39], p < 0.0001) increased all-cause, CVD, cancer, and respiratory disease mortality, respectively. RCS analyses showed largely linear associations between WWI and all mortality risks. Stratified analyses indicated that these associations were influenced by multiple factors, and that age was consistently the effect modifier across all associations.

CONCLUSIONS

WWI is an independent predictor of all-cause, CVD, cancer, and respiratory-related mortality in the adult asthma population. These findings highlight that WWI may have novel prognostic value as a simple and easily accessible obesity parameter in asthma patients.

Documentation of comorbidities, lifestyle factors, and asthma management during primary care scheduled asthma contacts

Systematically assessing asthma during follow-up contacts is important to accomplish comprehensive treatment. No previous long-term studies exist on how comorbidities, lifestyle factors, and asthma management details are documented in scheduled asthma contacts in primary health care (PHC). We showed comorbidities and lifestyle factors were poorly documented in PHC in this real-life, 12-year, follow-up study. Documented information on rhinitis was found in 8.9% and BMI, overweight, or obesity in ≤1.5% of the 542 scheduled asthma contacts. Of the 145 patients with scheduled asthma contacts, 6.9% had undergone revision of their inhalation technique; 16.6% had documentation of their asthma action plan. Screening of respiratory symptoms was recorded in 79% but nasal symptoms in only 15.5% of contacts. Lifestyle guidance interventions were found in <1% of contacts. These results, based on documented patient data, indicate a need exists to further improve the assessment and guidance of asthma patients in PHC.

Chinese expert consensus on the diagnosis, treatment, and management of asthma in women across life

Background

The epidemiology and severity of asthma vary by sex and age. The diagnosis, treatment, and management of asthma in female patients are quite challenging. However, there is hitherto no comprehensive and standardized guidance for female patients with asthma.

Methods

Corresponding search strategies were determined based on clinical concerns regarding female asthma. Search terms included "sex hormones and lung development", "sex hormone changes and asthma", "hormones and asthma immune response", "women, asthma", "children, asthma", "puberty, asthma", "menstruation, asthma", "pregnancy, asthma", "lactation, asthma", "menopause, asthma", "obesity, asthma", and "women, refractory, severe asthma". Literature was retrieved from PubMed/Medline, Embase, Cochrane Library, China Biology Medicine disc, China National Knowledge Infrastructure, Wanfang Data with the search date of July 30, 2022 as the last day. This consensus used the Grading of Recommendations Assessment, Development, and Evaluation to evaluate the strength of recommendation and quality of evidence.

Results

We collected basic research results and clinical evidence-based medical data and reviewed the effects of sex hormones, classical genetics, and epigenetics on the clinical presentation and treatment response of female patients with asthma under different environmental effects. Based on that, we formulated this expert consensus on the management of female asthma throughout the life cycle.

Conclusions

This expert consensus on the management of asthma in women throughout the life cycle provides diagnosis, treatment, and research reference for clinical and basic medical practitioners.

Age-related differences in associations between uncontrolled asthma, comorbidities and biomarkers in adult-onset asthma

OBJECTIVE

Adult-onset asthma is a recognized but heterogeneous phenotype and has been described to associate with poor asthma control. Knowledge about associations between clinical characteristics including comorbidities and control of adult-onset asthma is limited, especially in older populations. We aimed to study how clinical biomarkers and comorbidities are associated with uncontrolled asthma among middle-aged and older individuals with adult-onset asthma.

METHODS

Clinical examinations including structured interview, asthma control test (ACT), spirometry, skin prick test (SPT), blood sampling, and measurement of exhaled fractional nitric oxide (FeNO) was performed in a population-based adult-onset asthma cohort in 2019-2020 (n = 227, 66.5% female). Analyses were performed among all included, and separately in middle-aged (37-64 years, n = 120) and older (≥65 years, n = 107) participants.

RESULTS

In bivariate analysis, uncontrolled asthma (ACT ≤ 19) was significantly associated with a blood neutrophil count ≥5/µl, BMI ≥30, and several comorbidities. In multivariable regression analysis, uncontrolled asthma was associated with neutrophils ≥5/µl (OR 2.35; 95% CI 1.11-4.99). In age-stratified analysis, BMI ≥30 (OR 3.04; 1.24-7.50), eosinophils ≥0.3/µl (OR 3.17; 1.20-8.37), neutrophils ≥5/µl (OR 4.39; 1.53-12.62) and allergic rhinitis (OR 5.10; 1.59-16.30) were associated with uncontrolled asthma among the middle-aged. Among the older adults, uncontrolled asthma was only associated with comorbidities: chronic rhinitis (OR 4.08; 1.62-10.31), ischemic heart disease (OR 3.59; 1.17-10.98), malignancy (OR 3.10; 1.10-8.73), and depression/anxiety (OR 16.31; 1.82-146.05).

CONCLUSIONS

In adult-onset asthma, comorbidities were strongly associated with uncontrolled asthma among older adults, while clinical biomarkers including eosinophils and neutrophils in blood were associated with uncontrolled asthma among middle-aged.

Apigenin ameliorates non-eosinophilic inflammation, dysregulated immune homeostasis and mitochondria-mediated airway epithelial cell apoptosis in chronic obese asthma via the ROS-ASK1-MAPK pathway

BACKGROUND

Obese asthma is one of the important asthma phenotypes that have received wide attention in recent years. Excessive oxidative stress and different inflammatory endotypes may be important reasons for the complex symptoms, frequent aggravation, and resistance to traditional treatments of obese asthma. Apigenin (API), is a flavonoid natural small molecule compound with good anti-inflammatory and antioxidant activity in various diseases and proved to have the potential efficacy to combat obese asthma.

METHODS

In vivo, this study fed C57BL/6 J mice with high-fat diets(HFD)for 12 weeks and then stimulated them with OVA for 6 weeks to establish a model of chronic obese asthma, while different doses of oral API or dexamethasone were used for therapeutic interventions. In vitro, this study used HDM to stimulate human bronchial cells (HBEs) to establish the model and intervened with API or Selonsertib (SEL).

RESULTS

This study clarified that OVAinduced a type of mixed granulocytic asthma with elevated neutrophils and eosinophils in obese male mice fed with long-term HFD, which also exhibited mixed TH17/TH1/TH2 inflammation. Apigenin effectively suppressed this complex inflammation and acted as a regulator of immune homeostasis. Meanwhile, apigenin reduced AHR, inflammatory cell infiltration, airway epithelial cell apoptosis, airway collagen deposition, and lung oxidative stress via the ROS-ASK1-MAPK pathway in an obese asthma mouse model. In vitro, this study found that apigenin altered the binding status of TRAF6 to ASK1, inhibited ASK1 phosphorylation, and protected against ubiquitin-dependent degradation of ASK1, suggesting that ROS-activated ASK1 may be an important target for apigenin to exert anti-inflammatory and anti-apoptotic effects. To further verify the intervention mechanism, this study clarified that apigenin improved cell viability and mitochondrial function and inhibited apoptosis by interfering with the ROS-ASK1-MAPK pathway.

CONCLUSIONS

This study demonstrates for the first time the therapeutic effect of apigenin in chronic obese asthma and further clarifies its potential therapeutic targets. In addition, this study clarifies the specificity of chronic obese asthma and provides new options for its treatment.

From Beneath the Skin to the Airway Wall: Understanding the Pathological Role of Adipose Tissue in Comorbid Asthma-Obesity

This article provides a contemporary report on the role of adipose tissue in respiratory dysfunction. Adipose tissue is distributed throughout the body, accumulating beneath the skin (subcutaneous), around organs (visceral), and importantly in the context of respiratory disease, has recently been shown to accumulate within the airway wall: "airway-associated adipose tissue." Excessive adipose tissue deposition compromises respiratory function and increases the severity of diseases such as asthma. The mechanisms of respiratory impairment are inflammatory, structural, and mechanical in nature, vary depending on the anatomical site of deposition and adipose tissue subtype, and likely contribute to different phenotypes of comorbid asthma-obesity. An understanding of adipose tissue-driven pathophysiology provides an opportunity for diagnostic advancement and patient-specific treatment. As an exemplar, the potential impact of airway-associated adipose tissue is highlighted, and how this may change the management of a patient with asthma who is also obese. © 2023 American Physiological Society. Compr Physiol 13:4321-4353, 2023.

Utility of Hypoglycemic Agents to Treat Asthma with Comorbid Obesity

Adults with obesity may develop asthma that is ineffectively controlled by inhaled corticosteroids and long-acting beta-adrenoceptor agonists. Mechanistic and translational studies suggest that metabolic dysregulation that occurs with obesity, particularly hyperglycemia and insulin resistance, contributes to altered immune cell function and low-grade systemic inflammation. Importantly, in these cases, the same proinflammatory cytokines believed to contribute to insulin resistance may also be responsible for airway remodeling and hyperresponsiveness. In the past decade, new research has emerged assessing whether hypoglycemic therapies impact comorbid asthma as reflected by the incidence of asthma, asthma-related emergency department visits, asthma-related hospitalizations, and asthma-related exacerbations. The purpose of this review article is to discuss the mechanism of action, preclinical data, and existing clinical studies regarding the efficacy and safety of hypoglycemic therapies for adults with obesity and comorbid asthma.

Depression in Childhood Asthma vs. Adult-Onset Asthma: A Cross-Sectional Study from the National Health and Nutrition Examination Survey (NHANES)

Background: asthma, a chronic respiratory disease caused by inflammation and narrowing of the small airways in the lungs, is the most common chronic childhood disease. Prevalence of childhood asthma in the United States is 5.8%. In boys, prevalence is 5.7% and it is 6% in girls. Asthma is associated with other comorbidities such as major depressive disorder and anxiety disorder. This study explores the association between asthma and depression. Methods: we conducted a retrospective cross-sectional study using NHANES data from 2013 to 2018. Asthma and childhood onset asthma were assessed using questionnaires MCQ010 and MCQ025, respectively. Sociodemographic variables were summarized, and univariate analysis was performed to determine the association between asthma and major depressive disorder and its individual symptoms. Results: there were 402,167 participants from 2013−2018 in our study: no asthma in 84.70%; asthma in 15.30%. Childhood onset asthma (COA) included 10.51% and adult-onset asthma (AOA) included 4.79%. Median age of COA is 5 years and AOA is 41 years. Among the asthma groups, most AOA were females (67.77%, p < 0.0001), most COA were males (52.16%, p < 0.0001), and ethnicity was predominantly White in AOA (42.39%, p < 0001) and in COA (35.24%, p < 0.0001). AOA mostly had annual household income from $0−24,999 (35.91%, p < 0.0001), while COA mostly had annual household income from $25,000−64,999 (36.66%, p < 0.0001). There was a significantly higher prevalence of MDD in COA (38.90%) and AOA (47.30%) compared to NOA (31.91%). Frequency of symptoms related to MDD were found to have a significantly higher prevalence and severity in the asthma groups compared to no asthma, and slightly greater and more severe in AOA than in COA. Symptoms include having little interest in doing things (COA 18.38% vs. AOA 22.50% vs. NOA 15.44%), feeling down, depressed, or hopeless (COA 20.05% vs. AOA 22.77% vs. NOA 15.85%), having trouble sleeping or sleeping too much (COA 27.38% vs. AOA 23.15% vs. NOA 22.24%), feeling tired or having little energy (COA 39.17% vs. AOA 34.24% vs. NOA 33.97%), having poor appetite or overeating (COA 19.88% vs. AOA 20.02% vs. NOA 15.11%), feeling bad about yourself (COA 13.90% vs. AOA 13.79% vs. NOA 10.78%), having trouble concentrating on things (COA 12.34% vs. AOA 14.41% vs. NOA 10.06%), moving or speaking slowly or too fast (COA 8.59% vs. AOA 9.72% vs. NOA 6.09%), thinking you would be better off dead (COA 3.12% vs. AOA 4.38% vs. NOA 1.95%) and having the difficulties these problems have caused (COA 21.66% vs. AOA 26.73% vs. NOA 19.34%, p < 0.0001). Conclusion: MDD and related symptoms were significantly higher and more severe in participants with asthma compared to no asthma. Between adult-onset asthma compared to childhood onset asthma, adult-onset asthma had slightly greater and more severe MDD and related symptoms compared to childhood onset asthma.

Down-regulated surfactant protein B in obese asthmatics

BACKGROUND

Obesity is a common comorbid condition in adult asthmatics and known as a feature of asthma severity. However, the molecular mechanism under obesity-induced inflammation has not yet been fully understood.

OBJECTIVE

Considering the essential role of hydrophobic surfactant protein B (SP-B) in lung function, SP-B was targeted to examine its involvement in the development of obesity-induced airway inflammation in asthmatics.

METHODS

The aim was to examine an alteration in circulating SP-B according to obesity in adult asthmatics, 129 asthmatics were enrolled and classified into 3 groups (obese, overweight and normal-weight groups) according to body mass index (BMI). Circulating SP-B levels were determined by enzyme-linked immunosorbent assay. Four single nucleotide polymorphisms of SFTPB gene were genotyped. Serum ceramide levels were measured by liquid chromatography-tandem mass spectrometry.

RESULTS

Significantly lower serum SP-B levels were noted in the obese group than in the overweight or normal-weight group (p = .002). The serum SP-B level was significantly correlated with serum levels of C18:0 ceramide and transforming growth factor beta 1 as well as BMI (r = -0.200; r = -0.215; r = -0.332, p < .050 for all). An inverse correlation was noted between serum SP-B and fractional exhaled nitric oxide levels in female asthmatics (r = -0.287, p = .009). Genetic predisposition of the SFTPB gene at 9306 A>G to the obese and overweight groups was noted.

CONCLUSION

Obesity altered ceramide metabolism leading to pulmonary surfactant dysfunction and impaired resolution of airway inflammation, finally contributing to the phenotypes of obese asthmatics.

Determinants of Severe Asthma - A Long-Term Cohort Study in Northern Sweden

Background

Risk factors for severe asthma are not well described. The aim was to identify clinical characteristics and risk factors at study entry that are associated with severe asthma at follow-up in a long-term prospective population-based cohort study of adults with asthma.

Methods

Between 1986 and 2001, 2055 adults with asthma were identified by clinical examinations of population-based samples in northern Sweden. During 2012-2014, n = 1006 (71% of invited) were still alive, residing in the study area and participated in a follow-up, of which 40 were identified as having severe asthma according to ERS/ATS, 131 according to GINA, while 875 had other asthma. The mean follow-up time was 18.7 years.

Results

Obesity at study entry and adult-onset asthma were associated with severe asthma at follow-up. While severe asthma was more common in those with adult-onset asthma in both men and women, the association with obesity was observed in women only. Sensitization to mites and moulds, but not to other allergens, as well as NSAID-related respiratory symptoms was more common in severe asthma than in other asthma. Participants with severe asthma at follow-up had lower FEV₁, more pronounced FEV₁ reversibility, and more wheeze, dyspnea and nighttime awakenings already at study entry than those with other asthma.

Conclusion

Adult-onset asthma is an important risk factor for development of severe asthma in adults, and obesity increased the risk among women. The high burden of respiratory symptoms already at study entry also indicate long-term associations with development of severe asthma.

Long-Term Use of Short-Acting β2-Agonists in Patients With Adult-Onset Asthma

BACKGROUND

Short-term studies have associated high use of short-acting β₂-agonists (SABA) with increased risk of exacerbations, emergency visits, and asthma-related costs. However, no studies exist on long-term SABA use, and previous studies on the topic have not included information about adherence to inhaled corticosteroids (ICS) nor disease control, both affecting the need of SABA.

OBJECTIVE

To evaluate the clinical characteristics of SABA and ICS usage in newly diagnosed adult-onset asthma patients during a 12-year follow-up period.

METHODS

In the Seinäjoki Adult Asthma Study, 203 patients with adult-onset asthma were followed for 12 years. Information on dispensed SABA and ICS during the follow-up was obtained from the Finnish Social Insurance Institution. High SABA use was defined as ≥36 canisters in 12 years, corresponding to an average of ≥3 dispensed canisters/y.

RESULTS

Patients were dispensed median 6 (interquartile range: 3-16) SABA canisters and 48 (18-67) ICS canisters over 12 years, corresponding to 2 (1-4) and 11 (5-16) puffs/week, respectively. Only 10% of the patients were classified as high SABA users during this period. Obesity (body mass index ≥30) and high Airways Questionnaire 20 symptom scores at baseline predicted high long-term SABA use (incidence rate ratio: 1.53 [1.01-2.30] and 1.04 [1.00-1.08], respectively). High SABA users had higher ICS adherence, higher blood neutrophil counts, more comorbidities, and used more oral corticosteroid and antibiotic courses versus low SABA users.

CONCLUSION

High SABA use was infrequent in patients with confirmed adult-onset asthma. However, as high SABA use is associated with more severe asthma, these patients should be recognized in clinical practice.

STOP: an open label crossover trial to study ICS withdrawal in patients with a combination of obesity and low-inflammatory asthma and evaluate its effect on asthma control and quality of life

Background

Asthma patients with obesity often have a high disease burden, despite the use of high-dose inhaled corticosteroids (ICS). In contrast to asthmatics with normal weight, the efficacy of ICS in patients with obesity and asthma is often relatively low. Meanwhile, patients do suffer from side effects, such as weight gain, development of diabetes, cataract, or high blood pressure. The relatively poor response to ICS might be explained by the low prevalence of type 2 inflammatory patterns (T2-low) in patients with asthma and obesity. T2-low inflammation is characterized by low eosinophilic count, low Fractional exhaled NO (FeNO), no clinically allergy-driven asthma, and no need for maintenance oral corticosteroids (OCS). We aim to study whether ICS can be safely withdrawn in patients with T2-low asthma and obesity while maintaining an equal level of asthma control. Secondary outcomes focus on the prevalence of ‘false-negative’ T2-low phenotypes (i.e. T2-hidden) and the effect of ICS withdrawal on parameters of the metabolic syndrome. This study will lead to a better understanding of this poorly understood subgroup and might find new treatable traits.

Methods

The STOP trial is an investigator-initiated, multicenter, non-inferiority, open-label, crossover study aiming to assess whether ICS can be safely withdrawn in adults aged 17–75 years with T2-low asthma and obesity (body mass index (BMI) ≥ 30 kg/m2). Patients will be randomly divided into two arms (both n = 60). One arm will start with fixed-dose ICS (control group) and one arm will taper and subsequently stop ICS (intervention group). Patients in the intervention group will remain ICS naïve for ten weeks. After a washout of 4 weeks, patients will crossover to the other study arm. The crossover study takes 36 weeks to complete. Patients will be asked to participate in the extension study, to investigate the long-term metabolic benefits of ICS withdrawal.

Discussion

This study yields valuable data on ICS tapering in patients with T2-low asthma and obesity. It informs future guidelines and committees on corticosteroid-sparing algorithms in these patients.

Trial registration Netherlands Trial Register, NL8759, registered 2020–07-06, https://www.trialregister.nl/trial/8759.

Protocol version and date: version 2.1, 20 November 2020.

Adult but not childhood onset asthma is associated with the metabolic syndrome, independent from body mass index

INTRODUCTION

Adult-onset asthma (AOA) is usually more severe compared to childhood onset asthma (CoA). Given the increasing evidence that AoA is associated with obesity, we investigated the relationship of other related metabolic comorbid conditions with AoA compared to CoA.

STUDY DESIGN AND METHODS

This cross-sectional study compared the metabolic syndrome and lipid derived inflammatory markers in patients with AoA, CoA and age- and sex-matched control subjects without asthma. Participants were asthma patients visiting the outpatient clinic of two teaching hospitals in Rotterdam, The Netherlands. All participants underwent lung function tests, blood tests and physical activity tracking. AoA was defined as asthma age of onset after the age of 18 years. Metabolic syndrome was defined according to the international joint interim statement criteria.

RESULTS

Eighty-one participants were included (27 AoA, 25 CoA, 29 controls). AoA was associated with the metabolic syndrome (Odds Ratio = 3.64 95% CI (1.16-11.42) p = 0.03, Nagelkerke R² = 0.26), adjusted for age, sex, body mass index and smoking habits. AoA patients had higher median serum IL-6 and leptin-adiponectin (LA) ratio compared to controls (IL-6 (pg/mL): 3.10 [1.11-4.30] vs. 1.13 [0.72-1.58], p = 0.002 and LA ratio (pg/mL): 6.21 [2.45-14.11] vs. 2.24 [0.67-4.71], p = 0.0390). This was not observed in CoA and controls.

CONCLUSION

AoA was associated with the metabolic syndrome and its related pro-inflammatory endocrine and cytokine status. This may suggest adipose tissue derived inflammatory markers play a role in the pathophysiology of AoA.

Revisiting Late-Onset Asthma: Clinical Characteristics and Association with Allergy

The Global Initiative for Asthma (GINA) 2020 defines late-onset asthma (LOA) as one of the clinical phenotypes of asthma wherein patients, particularly women, present with asthma for the first time in adult life, tend to be non-allergic and often require higher doses of inhaled corticosteroids (ICS) or are relatively refractory to corticosteroid treatment. In this review, we examine the published literature improve the understanding of the following aspects of LOA: 1) the age cut-off for its diagnosis; 2) its distinct clinical phenotypes, characteristics and risk factors; and 3) its association with allergic comorbidities and conditions. Overall, our review reveals that clinicians and researchers have used multiple age cut-offs to define LOA, with cut-off ages ranging from >12 years to ≥65 years. LOA has also been classified into several distinct phenotypes, some of which drastically differ in their clinical characteristics, course and prognosis. Although LOA has traditionally been considered non-allergic in nature, our review indicates that it is commonly associated with allergic features and comorbidities. Our findings suggest that there is an urgent need for the development of more clear clinical practice guidelines that can provide more clarity on the definition and other aspects of LOA. In addition, the association of LOA and allergy needs to be re-examined to frame a more optimal treatment strategy for patients with LOA.