The impact of therapy on the risk of asthma in type 2 diabetes

Obesity-related Asthma: A Pathobiology-based Overview of Existing and Emerging Treatment Approaches

Although obesity-related asthma is associated with worse asthma outcomes, optimal treatment approaches for this complex phenotype are still largely unavailable. This state-of-the-art review article synthesizes evidence for existing and emerging treatment approaches for obesity-related asthma and highlights pathways that offer potential targets for novel therapeutics. Existing treatments targeting insulin resistance and obesity, including metformin and GLP-1 (glucagon-like-peptide 1) receptor agonists, have been associated with improved asthma outcomes, although GLP-1R agonist data in asthma are limited to individuals with comorbid obesity. Monoclonal antibodies approved for treatment of moderate to severe asthma generally appear to be effective in individuals with obesity, although this is based on retrospective or secondary analysis of clinical trials; moreover, although most of these asthma biologics are approved for use in the pediatric population, the impact of obesity on their efficacy has not been well studied in youth. Potential therapeutic targets being investigated include IL-6, arginine metabolites, nitro-fatty acids, and mitochondrial antioxidants, with clinical trials for each currently underway. Potential therapeutic targets include adipose tissue eosinophils and the GLP-1-arginine-advanced glycation end products axis, although data in humans are still needed. Finally, transcriptomic and epigenetic studies of "obese asthma" demonstrate enrichment of IFN-related signaling pathways, Rho-GTPase pathways, and integrins, suggesting that these too could represent future treatment targets. We advocate for further study of these potential therapeutic mechanisms and continued investigation of the distinct inflammatory pathways characteristic of obesity-related asthma, to facilitate effective treatment development for this unique asthma phenotype.

Allergic Diseases and T2DM:A Bidirectional Multivariable Mendelian Randomization Study and Mediation Analysis

BACKGROUND

Clinical studies involving observation have uncovered a mutual relationship between allergic disorders and diabetes, yet the precise causal link remains undetermined.

METHODS

We conducted two-sample bidirectional Mendelian randomization analyses using single nucleotide polymorphisms (SNPs) associated with allergic conditions (asthma, allergic rhinitis, atopic dermatitis) from genome-wide studies and SNPs related to type 2 diabetes from FinnGen. Initially, we evaluated the causal link between allergic disorders and type 2 diabetes through a univariate Mendelian randomization study, incorporating inverse variance weighting, MR-Egger, and the weighted median estimator. To address potential confounding, we employed multivariate Mendelian randomization. Finally, we validated mediators influencing the correlation between asthma and type 2 diabetes.

RESULTS

The Inverse variance weighte method showed that asthma genetically increased the risk of type 2 diabetes (Asthma- type 2 diabetes: β(95%CI)＝0.892(0.152～1.632), P = 0.018). Allergic rhinitis and type 2 diabetes exhibit a mutual protective effect: β(95% CI)＝-1.333(-2.617 to -0.049), P = 0.042；type 2 diabetes - Allergic rhinitis: β(95%CI)＝-0.002(-0.004 to -0.000), P = 0.018). The Multivariable Mendelian randomization study results showed that after after excluding confounding factors, asthma still demonstrates statistical significance in relation to type 2 diabetes. Through mediation analysis, it was discovered that lung function and the percentage of monocytes in leukocytes exert an inhibitory effect on the mediation between asthma and type 2 diabetes.

CONCLUSION

The Multivariable Mendelian randomization study indicates asthma as a risk factor for type 2 diabetes.Lung function, and the percentage of monocytes in leukocytes, play an inhibitory role in asthma and type 2 diabetes mediating effects.

Association of metformin use with asthma development and adverse outcomes: A systematic review and meta-analysis

BACKGROUND

Asthma and diabetes are prevalent chronic diseases affecting a significant population globally. Research has suggested that metformin, a commonly used medication for diabetes management, may also have beneficial effects in enhancing asthma outcomes. Considering the comorbidity of asthma and diabetes, a comprehensive analysis was performed to investigate the efficacy of metformin in reducing adverse outcomes of asthma patients with diabetes.

METHODS

To gather relevant data, we conducted a systematic search of the PubMed, Embase, and CENTRAL databases for observational studies published prior to September 2023. We specifically looked for studies involving individuals diagnosed with both asthma and diabetes, comparing the incidence and severity of asthma exacerbations in metformin users versus nonusers. The inclusion criteria encompassed studies that recruited participants aged 18 years and older. The primary outcome of interest was the risk of newly developing asthma, while secondary outcomes included the adjusted risk of asthma-induced exacerbations, emergency room visits, and hospitalizations. All data analyses and visualizations were performed using the R programming language.

RESULTS

We identified and included 7 studies involving a total of 1,176,398 patients in our analysis. The pooled effect size indicated a potential reduction in the incidence of newly developed asthma among patients with type 2 diabetes who used metformin, although this finding did not reach statistical significance. Similar conclusions have also been observed in other outcomes, such as exacerbation, asthma-related emergency department visits, risk of systemic corticosteroid prescription. The only positive outcome is that the use of metformin can reduce the chance of patients being hospitalized due to asthma.

CONCLUSION

In most outcome indicators, it cannot be assumed that the use of metformin can reduce asthma-related adverse events. However, the conclusion is not so certain, and longer observation and more evidence are still required. Metformin still shows some potential in the intervention of respiratory diseases.

Impact of metabolic and weight components on incident asthma using a real-world cohort

BACKGROUND

Obesity and metabolic dysregulation (MetD) have increasing prevalence and adversely affect asthma morbidity and therapeutic response.

OBJECTIVE

To determine the role of weight and MetD on incident asthma in adulthood.

METHODS

In a retrospective, longitudinal cohort of patients, we performed a time-to-asthma diagnosis analysis after a 3-year landmark period (t0-t3) during which weight and MetD components were evaluated. We assessed incident asthma risk with MetD components and weight.

RESULTS

In total, 90,081 patients met the inclusion criteria, with 836 cases (0.93%) of incident asthma in our primary cohort. Diabetes present at t0, but no other MetD components, was associated with increased risk of asthma (adjusted hazard ratio = 1.85, 95% CI: 1.27-2.71, P = .0002). The effect of weight on asthma risk, independent of other MetD components, identified individuals with overweight or obesity as having a 10-year attributable risk of 15.4%. Metformin was prescribed more frequently, and hemoglobin A1c levels were lower in patients with diabetes in whom asthma did not develop (P < .0001).

CONCLUSION

Weight and diabetes prevention and management represent modifiable risk factors for adult asthma development.

Asthma and Hyperglycemia: Exploring the Interconnected Pathways

The interplay between asthma and glucose metabolism disorders, such as hyperglycemia, has gained increasing attention due to the potential exacerbation of asthma symptoms and severity. This review explores the complex relationship between hyperglycemia and asthma, emphasizing the pathophysiological links, the impact of glucose metabolism disorders on asthma, and the effects of asthma medications on glucose levels. Hyperglycemia, often induced by asthma treatments like corticosteroids, has been associated with an increased risk of asthma exacerbations. This review delves into the pathophysiology underlying this association, highlighting the role of insulin resistance, metabolic syndrome, and obesity in both the development and management of asthma. Metabolic syndrome, characterized by abdominal obesity and hyperglycemia, independently increases the risk of worsening respiratory symptoms and asthma. Furthermore, this review examines the influence of various antidiabetic medications on asthma outcomes. Biguanides, like metformin, have shown promise in improving asthma outcomes in patients with type 2 diabetes mellitus and asthma. However, other medications have mixed results regarding their impact on asthma control and lung function. Considering these findings, this review advocates for further research into the role of metabolic pathways in asthma management. It calls for comparative studies and the inclusion of asthma-related outcomes in clinical trials of antidiabetic drugs to better understand their potential benefits for individuals with obesity and concurrent asthma.

Unraveling the Link between Ιnsulin Resistance and Bronchial Asthma

Evidence from large epidemiological studies has shown that obesity may predispose to increased Th2 inflammation and increase the odds of developing asthma. On the other hand, there is growing evidence suggesting that metabolic dysregulation that occurs with obesity, and more specifically hyperglycemia and insulin resistance, may modify immune cell function and in some degree systemic inflammation. Insulin resistance seldom occurs on its own, and in most cases constitutes a clinical component of metabolic syndrome, along with central obesity and dyslipidemia. Despite that, in some cases, hyperinsulinemia associated with insulin resistance has proven to be a stronger risk factor than body mass in developing asthma. This finding has been supported by recent experimental studies showing that insulin resistance may contribute to airway remodeling, promotion of airway smooth muscle (ASM) contractility and proliferation, increase of airway hyper-responsiveness and release of pro-inflammatory mediators from adipose tissue. All these effects indicate the potential impact of hyperinsulinemia on airway structure and function, suggesting the presence of a specific asthma phenotype with insulin resistance. Epidemiologic studies have found that individuals with severe and uncontrolled asthma have a higher prevalence of glycemic dysfunction, whereas longitudinal studies have linked glycemic dysfunction to an increased risk of asthma exacerbations. Since the components of metabolic syndrome interact with one another so much, it is challenging to identify each one's specific role in asthma. This is why, over the last decade, additional studies have been conducted to determine whether treatment of type 2 diabetes mellitus affects comorbid asthma as shown by the incidence of asthma, asthma control and asthma-related exacerbations. The purpose of this review is to present the mechanism of action, and existing preclinical and clinical data, regarding the effect of insulin resistance in asthma.

Management of the pediatric patient with asthma and obesity

Asthma and obesity are 2 of the most significant chronic diseases of childhood. Both are major public health problems that have been increasing in prevalence. Obesity increases the risk of developing asthma in children, and in children with asthma, obesity increases asthma severity and morbidity. The nature of this relationship is complex and not fully understood, but some pediatric patients with "obesity-related asthma" may represent a phenotype that differs from the more classical, atopic pediatric asthma. In this review, we investigate and discuss some of the currently available literature regarding treatment for asthma complicated by obesity in the pediatric population. We cover the importance of healthy lifestyle modifications, management of obesity-related comorbidities, and the potential role of nutritional supplementation or modification. We then review recent literature, mostly in adults, investigating the potential role of obesity or diabetes medications in the management of patients with asthma who have obesity. Finally, we discuss some of the necessary next steps before these potential new treatments can be considered as part of the standard clinical management of asthma.

Metformin regulates the effects of IR and IGF-1R methylation on mast cell activation and airway reactivity in diabetic rats with asthma through miR-152-3p/DNMT1 axis

BACKGROUND/AIM

Metformin is a drug for treating type 2 diabetes mellitus (T2DM). Recently, metformin has been shown to reduce the risks of asthma-associated outcomes and asthma deterioration, thereby holding promise as a superior medicine for diabetic patients with asthma. However, the mechanism by which metformin reduces diabetic asthma is yet to be clarified. This study aimed at ascertaining the downstream molecules underlying the effect of metformin on the activation of mast cells (MCs) and airway reactivity in a concomitant diabetic and asthmatic rat model.

METHODS

A T2DM model was induced utilizing a high-fat diet and streptozotocin. Then, 10% ovalbumin was utilized to stimulate asthma-like pathology in the T2DM rats. RBL-2H3 cells were induced by anti-dinitrophenyl-specific immunoglobulin E for constructing an in vitro model. Luciferase assay and RNA immunoprecipitation (IP) assay were conducted to identify the interaction between microRNA-152-3p (miR-152-3p) and DNA methyltransferase 1 (DNMT1), while chromatin IP to identify the binding of DNMT1 to insulin receptor (IR) and insulin-like growth factor 1 receptor (IGF-1R) promoters. The effects of metformin on both pathological changes in vivo and biological behaviors of cells were evaluated. Using gain- and loss-of-function approaches, we assessed the role of the two interactions in the metformin-induced effect.

RESULTS

It was suggested that metformin could impede the MC activation and airway resistance in the concomitant diabetic and asthmatic rats. Additionally, metformin downregulated IR and IGF-1R through DNMT1-dependent methylation to repress MC activation and airway resistance. DNMT1 was testified to be a target gene of miR-152-3p. Furthermore, miR-152-3p-induced silencing of DNMT1 was blocked by metformin, hence restraining MC activation and airway resistance.

CONCLUSION

The findings cumulatively demonstrate that metformin downregulates IR/IGF-1R to block MC activation and airway resistance via impairing the binding affinity between miR-152-3p and DNMT1.

Cardiovascular diseases or type 2 diabetes mellitus and chronic airway diseases: mutual pharmacological interferences

Chronic airway diseases (CAD), mainly asthma and chronic obstructive pulmonary disease (COPD), are frequently associated with different comorbidities. Among them, cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) pose problems for the simultaneous treatment of CAD and comorbidity. Indeed, there is evidence that some drugs used to treat CAD negatively affect comorbidity, and, conversely, some drugs used to treat comorbidity may aggravate CAD. However, there is also growing evidence of some beneficial effects of CAD drugs on comorbidities and, conversely, of the ability of some of those used to treat comorbidity to reduce the severity of lung disease. In this narrative review, we first describe the potential cardiovascular risks and benefits for patients using drugs to treat CAD and the potential lung risks and benefits for patients using drugs to treat CVD. Then, we illustrate the possible negative and positive effects on T2DM of drugs used to treat CAD and the potential negative and positive impact on CAD of drugs used to treat T2DM. The frequency with which CAD and CVD or T2DM are associated requires not only considering the effect that drugs used for one disease condition may have on the other but also providing an opportunity to develop therapies that simultaneously favorably impact both diseases.

The Association Between Insulin Use and Asthma: An Epidemiological Observational Analysis and Mendelian Randomization Study

BACKGROUND

Asthma is a common respiratory disease caused by genetic and environmental factors, but the contribution of insulin use to the risk of asthma remains unclear. This study aimed to investigate the association between insulin use and asthma in a large population-based cohort, and further explore their causal relationship by Mendelian randomization (MR) analysis.

METHODS

An epidemiological study including 85,887 participants from the National Health and Nutrition Examination Survey (NHANES) 2001-2018 was performed to evaluate the association between insulin use and asthma. Based on the inverse-variance weighted approach, MR analysis were conducted to estimate the causal effect of insulin use on asthma from the UKB and FinnGen datasets, respectively.

RESULTS

In the NHANES cohort, we found that insulin use was associated with an increased risk of asthma [odd ratio (OR) 1.38; 95% CI 1.16-1.64; p < 0.001]. For the MR analysis, we found a causal relationship between insulin use and a higher risk of asthma in both Finn (OR 1.10; p < 0.001) and UK Biobank cohorts (OR 1.18; p < 0.001). Meanwhile, there was no causal association between diabetes and asthma. After multivariable adjustment for diabetes in UKB cohort, the insulin use remained significantly associated with an increased risk of asthma (OR 1.17, p < 0.001).

CONCLUSIONS

An association between insulin use and an increased risk of asthma was found via the real-world data from the NHANES. In addition, the current study identified a causal effect and provided a genetic evidence of insulin use and asthma. More studies are needed to elucidate the mechanisms underlying the association between insulin use and asthma.

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.

Metformin and the Risk of Chronic Urticaria in Patients with Type 2 Diabetes

We conducted this study to determine the effect of metformin use on the risk of new-onset chronic urticaria in patients with type 2 diabetes (T2D). In total, 24,987 pairs of metformin users and nonusers were identified with propensity score-matching from Taiwan's National Health Insurance Research Database from 1 January 2000, to 31 December 2017. Multivariable Cox proportional hazards models were used to compare the risks of chronic urticaria development, severe chronic urticaria, and hospitalization for chronic urticaria between metformin users and nonusers. Compared with metformin nonuse, the aHRs (95% CI) for metformin use in chronic urticaria development, severe chronic urticaria, and hospitalization for chronic urticaria were 1.56 (1.39-1.74), 0.40 (0.12-1.30), and 1.45 (0.82-2.56), respectively. The cumulative incidence of chronic urticaria development was significantly higher in metformin users than in nonusers (p < 0.0001). A longer average cumulative duration of metformin use was associated with higher risks of new-onset and hospitalization for chronic urticaria than metformin nonuse. This nationwide cohort study showed that metformin use was associated with a significantly higher risk of chronic urticaria development. A longer average cumulative duration of metformin use was associated with a higher risk of outcomes. More prospective studies are needed to verify our results.

Metformin and the Development of Asthma in Patients with Type 2 Diabetes

We conducted this study to compare the risks of asthma development and exacerbation between metformin users and nonusers. Overall, 57,743 propensity score-matched metformin users and nonusers were identified from Taiwan’s National Health Insurance Research Database between 1 January 2000, and 31 December 2017. We used the Cox proportional hazards model with robust standard error estimates to compare the risks of asthma onset, exacerbation, and hospitalization for asthma in participants with type 2 diabetes (T2D). Compared with metformin nonuse, the aHRs (95% CI) for metformin use in asthma development, exacerbation, and hospitalization for asthma were 1.13 (1.06−1.2), 1.62 (1.35−1.95), and 1.5 (1.22−1.85), respectively. The cumulative incidences of asthma development, exacerbation, and hospitalization for asthma were significantly higher in metformin users than nonusers (p < 0.001). A longer cumulative duration of metformin use for more than 728 days was associated with significantly higher risks of outcomes than metformin nonuse. Our study demonstrated that metformin users showed significantly higher risks of asthma development, exacerbation, and hospitalization for asthma than metformin nonusers. Moreover, metformin use for more than 728 days was associated with higher risks of outcomes. A randomized control study is warranted to verify our results.

Association of dipeptidyl peptidase-4 inhibitor use and the risk of asthma development among type 2 diabetes patients

Background:

Numerous studies have shown that dipeptidyl peptidase-4 inhibitors (DPP-4i) may regulate immunological pathways implicated in asthma. The association between DPP-4i use and risk of asthma development is limited, however.

Aim:

We aimed to evaluate if DPP-4i treatment in individuals with type 2 diabetes mellitus (T2DM) is associated with a lower risk and severity of asthma.

Methods:

We performed a population-based retrospective cohort study using the Longitudinal National Health Insurance Research database between 2008 and 2015. After one-to-four propensity score matching from 1,914,201 patients with defined criteria, we enrolled 3001 patients who were on DPP-4i (DPP-4i group) for a diagnosis of T2DM but without a diagnosis of asthma for further analysis. Cox proportional hazards regression analysis was performed to estimate and compare the risk of developing and severity of asthma, including no acute exacerbations event (No-AE), acute exacerbations (AEs), status asthmaticus (Status), and required endotracheal intubation (ET-tube intubated), between the two groups.

Results:

The participants had a mean age of 66.05 ± 17.23 years and the mean follow-up time was 4.96 ± 4.39 years. The risk of asthma development was significantly lower in the DPP-4i group than in the non-DPP-4i group [adjusted hazard ratio (HR) = 0.65; 95% confidence interval (CI) = 0.29–0.83; p < 0.001], with a class effect. This trend was observed for severity of asthma as No-AE (HR = 0.55; 95% CI = 0.24–0.70; p < 0.001), AE (HR = 0.57; 95% CI = 0.26–0.73; p < 0.001), and Status (HR = 0.78; 95% CI = 0.35–0.99; p = 0.047), but not in ET-tube intubated cases (HR = 0.96; 95% CI = 0.43–1.22; p = 0.258).

Conclusion:

The use of DPP-4i decreased the risk and severity of asthma with a class effect among No-AE, AE, status of asthma events, but not in ET-tube intubated events. Our report suggests that DPP-4i may play a role in attenuating the impact of asthma on incidence in the future and on more severe forms of disease exacerbation in T2DM patients.

Association between novel Glucose-Lowering drugs and risk of Asthma: A network Meta-Analysis of cardiorenal outcome trials

AIMS

This network meta-analysis aimed to evaluate the asthma risk associated with dipeptidyl peptidase (DPP)-4 inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1RAs), and sodium-glucose co-transporter (SGLT) 2 inhibitors.

METHODS

Electronic databases were systematically searched up to March 2021 to include placebo-controlled cardiovascular (or cardiorenal) outcome trials that reported the asthma incidents in patients taking DPP-4 inhibitors, GLP-1RAs, or SGLT2 inhibitors. A random-effects network meta-analysis was conducted to estimate their odds ratio (ORs) and 95% confidence intervals (CIs).

RESULTS

Nineteen trials including 218 asthma cases among 159,705 patients were included. Compared with placebo, SGLT2 inhibitors (OR, 0.59; 95% CI, 0.38-0.93) were significantly associated with a decreased risk of asthma while both DPP-4 inhibitors and GLP-1RAs did not significantly affect asthma risk. SGLT2 inhibitors were significantly associated with a lower risk of asthma than DPP-4 inhibitors (OR, 0.38; 95% CI, 0.18-0.79). There was no association between GLP-1RAs and DPP-4 inhibitors and between SGLT2 inhibitors and GLP-1RAs in risk of asthma.

CONCLUSIONS

SGLT2 inhibitors might protect against asthma while DPP-4 inhibitors and GLP-1RAs did not significantly affect the asthma incident. Given the underreporting of asthma in this study, further investigations using real-world data as well as mechanistic studies are warranted to confirm our results.

Epidemiology, management and the associated burden of mental health illness, atopic and autoimmune conditions, and common infections in alopecia areata: protocol for an observational study series

INTRODUCTION

Alopecia areata (AA) is a common cause of immune-mediated non-scarring hair loss. Links between AA and common mental health, autoimmune and atopic conditions, and common infections have previously been described but remain incompletely elucidated and contemporary descriptions of the epidemiology of AA in the UK are lacking.

METHODS AND ANALYSIS

Retrospective study series using a large population-based cohort (5.2 million) from the Oxford Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) database, exploring four themes: AA epidemiology, mental health comorbidities, autoimmune/atopic associations and common infections.In the epidemiology theme, we will describe the incidence and point prevalence of AA overall and by age, sex and sociodemographic factors. Healthcare utilisation (primary care visits and secondary care referrals) and treatments for AA will also be assessed. In the mental health theme, we will explore the prevalence and incidence of mental health conditions (anxiety, depressive episodes, recurrent depressive disorder, adjustment disorder, agoraphobia, self-harm and parasuicide) in people with AA compared with matched controls. We will also explore the mental health treatment patterns (medication and psychological interventions), time off work and unemployment rates. Within the autoimmune/atopic associations theme, we will examine the prevalence of atopic (atopic dermatitis, allergic rhinitis, asthma) and autoimmune conditions (Crohn's disease, ulcerative colitis, coeliac disease, type 1 diabetes, Hashimoto's thyroiditis, Graves' disease, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, systemic lupus erythematosus (SLE), polymyalgia rheumatica, Sjögren's syndrome, psoriasis, vitiligo, multiple sclerosis, pernicious anaemia) in people with AA compared with matched controls. We will also estimate the incidence of new-onset atopic and autoimmune conditions after AA diagnosis. Within the common infections theme, we will examine the incidence of common infections (respiratory tract infection, pneumonia, acute bronchitis, influenza, skin infection, urinary tract infection, genital infections, gastrointestinal infection, herpes simplex, herpes zoster, meningitis, COVID-19) in people with AA compared with matched controls.

ETHICS AND DISSEMINATION

The Health Research Authority decision tool classed this a study of usual practice, ethics approval was not required. Study approval was granted by the RCGP RSC Study Approval Committee. Results will be disseminated through peer-reviewed publications.

OBSERVATIONAL STUDY REGISTRATION NUMBER

NCT04239521.

Therapeutic approaches targeting molecular signaling pathways common to diabetes, lung diseases and cancer

Diabetes mellitus (DM), is the most common metabolic disease and is characterized by sustained hyperglycemia. Accumulating evidences supports a strong association between DM and numerous lung diseases including chronic obstructive pulmonary disease (COPD), fibrosis, and lung cancer (LC). The global incidence of DM-associated lung disorders is rising and several ongoing studies, including clinical trials, aim to elucidate the molecular mechanisms linking DM with lung disorders, in particular LC. Several potential mechanisms, including hyperglycemia, hyperinsulinemia, glycation, inflammation, and hypoxia, are cited as plausible links between DM and LC. In addition, studies also propose a connection between the use of anti-diabetic medications and reduction in the incidence of LC. However, the exact cause for DM associated lung diseases especially LC is not clear and is an area under intense investigation. Herein, we review the biological links reported between DM and lung disorders with an emphasis on LC. Furthermore, we report common signaling pathways (eg: TGF-β, IL-6, HIF-1, PDGF) and miRNAs that are dysregulated in DM and LC and serve as molecular targets for therapy. Finally, we propose a nanomedicine based approach for delivering therapeutics (eg: IL-24 plasmid DNA, HuR siRNA) to disrupt signaling pathways common to DM and LC and thus potentially treat DM-associated LC. Finally, we conclude that the effective modulation of commonly regulated signaling pathways would help design novel therapeutic protocols for treating DM patients diagnosed with LC.

Asthma Exacerbations in Patients with Type 2 Diabetes and Asthma on Glucagon-like Peptide-1 Receptor Agonists

Rationale: GLP-1R (glucagon-like peptide-1 receptor) agonists are approved to treat type 2 diabetes mellitus and obesity. GLP-1R agonists reduce airway inflammation and hyperresponsiveness in preclinical models.Objectives: To compare rates of asthma exacerbations and symptoms between adults with type 2 diabetes and asthma prescribed GLP-1R agonists and those prescribed SGLT-2 (sodium-glucose cotransporter-2) inhibitors, DPP-4 (dipeptidyl peptidase-4) inhibitors, sulfonylureas, or basal insulin for diabetes treatment intensification.Methods: This study was an electronic health records-based new-user, active-comparator, retrospective cohort study of patients with type 2 diabetes and asthma newly prescribed GLP-1R agonists or comparator drugs at an academic healthcare system from January 2000 to March 2018. The primary outcome was asthma exacerbations; the secondary outcome was encounters for asthma symptoms. Propensity scores were calculated for GLP-1R agonist and non-GLP-1R agonist use. Zero-inflated Poisson regression models included adjustment for multiple covariates.Measurements and Main Results: Patients initiating GLP-1R agonists (n = 448), SGLT-2 inhibitors (n = 112), DPP-4 inhibitors (n = 435), sulfonylureas (n = 2,253), or basal insulin (n = 2,692) were identified. At 6 months, asthma exacerbation counts were lower in persons initiating GLP-1R agonists (reference) compared with SGLT-2 inhibitors (incidence rate ratio [IRR], 2.98; 95% confidence interval [CI], 1.30-6.80), DPP-4 inhibitors (IRR, 2.45; 95% CI, 1.54-3.89), sulfonylureas (IRR, 1.83; 95% CI, 1.20-2.77), and basal insulin (IRR, 2.58; 95% CI, 1.72-3.88). Healthcare encounters for asthma symptoms were also lower among GLP-1R agonist users.Conclusions: Adult patients with asthma prescribed GLP-1R agonists for type 2 diabetes had lower counts of asthma exacerbations compared with other drugs initiated for treatment intensification. GLP-1R agonists may represent a novel treatment for asthma associated with metabolic dysfunction.

The epidemiology of eczema in children and adults in England: A population-based study using primary care data

BACKGROUND

Whilst eczema is a common inflammatory skin condition, we lack contemporary estimates of disease incidence and prevalence across the lifespan.

OBJECTIVE

To estimate the incidence and prevalence of eczema in children and adults in England and variation by sociodemographic factors (sex, socio-economic status, ethnicity, and geography).

METHODS

We used the Royal College of General Practitioners Research and Surveillance Centre primary care research database of 3.85 million children and adults registered with participating general practitioner practices between 2009 and 2018 inclusive. Eczema incidence was defined as the first-ever diagnosis of eczema recorded in the primary care record, and eczema prevalence was defined as fulfilment of criteria for active eczema (two eczema records appearing in the primary care record within any one-year period).

RESULTS

Eczema incidence was highest in infants younger than 1 year (15.0 per 100 person-years), lowest in adults aged 40-49 (0.35 p/100 person-years), and increased from middle age to a second smaller peak in people 80 years or older (0.79 p/100 person-years). Eczema prevalence was highest in children aged 2 (16.5%) and lowest in adults aged 30-39 (2.8%). Eczema incidence was higher in male infants (<2) and male adults older than 70; for all other ages, incidence was higher in females. Eczema was more common in Asian and black ethnic groups than in people of white ethnicity. Higher socio-economic status was associated with a greater incidence of eczema in infants younger than 2, but the reverse was seen for all other age groups. Both incidence and prevalence of eczema were greater in urban settings and in North-West England.

CONCLUSIONS AND CLINICAL RELEVANCE

Eczema has a bimodal distribution across the lifespan. We observed differences in incidence and prevalence of eczema by ethnicity, geography, sex, and socio-economic status, which varied in magnitude throughout life.

Epidemiology and management of atopic dermatitis in England: an observational cohort study protocol

INTRODUCTION

Atopic dermatitis (AD) is one of the most common inflammatory skin conditions in both children and adults. Despite this, contemporary descriptions of the incidence, prevalence and current management of the condition in the UK are lacking.

METHODS AND ANALYSIS

We will perform a series of retrospective studies using a large population-based cohort derived from the Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) network database to explore two key research themes: AD epidemiology and AD management.In the epidemiology theme, we will describe the incidence and prevalence of AD in children and adults in England from 2009 to 2018 inclusive. We will stratify findings by age, national Index of Multiple Deprivation (IMD), ethnicity, urban-rural environment and geographic location; and explore independent associations of these features with AD in multivariable models.In the management theme, we will explore healthcare utilisation and treatment in people with AD. Regarding healthcare utilisation, we will evaluate rates of AD-associated primary care visits and specialist dermatology referrals in people with AD. Rates will be stratified by age, gender, socioeconomic IMD quintile and ethnicity. We will describe contemporary treatment by estimating prescribing rates across medication classes used in AD (emollients, topical corticosteroids by potency, topical calcineurin inhibitors, topical antimicrobials, antihistamines, oral corticosteroids and systemic immunomodulatory therapies) overall, and by age and sociodemographic groupings. We will also examine trends in prescribing over the study period. In people first diagnosed with AD during the study period, we will describe differences in treatment escalation by sociodemographic factors using time-to-event analysis.

ETHICS AND DISSEMINATION

The Health Research Authority decision tool classed this a study of 'usual practice', ethics approval was not required. Study approval was granted by the RCGP RSC Study Approval Committee. Results will be disseminated through peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03823794.

Association of Metformin Use with Asthma Exacerbation in Patients with Concurrent Asthma and Diabetes: A Systematic Review and Meta-Analysis of Observational Studies

Background

Asthma and diabetes are both diseases that affect a wide range of people worldwide. As a common treatment for diabetes, metformin has also been reported to be effective in improving asthma outcomes. We conducted a combined analysis to examine the efficacy of metformin in reducing asthma exacerbation in patients with concurrent asthma and diabetes.

Methods

We searched the PubMed, Embase, and CENTRAL databases for articles published prior to April 2020 to find observational studies of individuals with concurrent asthma and diabetes that compared the risk of asthma exacerbation between metformin users and nonusers. Two researchers separately screened the studies, extracted data, and evaluated the risk of bias. The primary outcome was the adjusted risk of asthma exacerbation. The secondary outcomes were the adjusted risk of asthma-related hospitalization and emergency room visits. Review Manager was used for data analysis and plotting. I² and χ² tests were used to estimate heterogeneity. A random effects or fixed effects model was used depending on the heterogeneity. Odds ratios were calculated for dichotomous variables.

Results

We included two studies with a total of 25252 patients. The pooled effect size showed that metformin was inversely associated with a risk of asthma exacerbation (OR = 0.65, 95% CI 0.28–1.48; χ² = 5.42, P=0.02; I² = 82%), asthma-related emergency department visits (OR = 0.81, 95% CI 0.74–0.89; χ² = 0.36, P=0.55; I² = 0%), and hospitalizations (OR = 0.43, 95% CI 0.14–1.29; χ² = 4.01, P=0.05; I² = 75%).

Conclusion

This meta-analysis suggested that metformin decreased the risk of asthma-related emergency room visits for patients with concurrent asthma and diabetes. Metformin reduced the risk of asthma-related hospitalization and exacerbation but was not statistically significant. More randomized trials involving larger samples should be considered, and the mechanisms of these effects need to be fully elucidated.

Metabolic Dysfunction and Asthma: Current Perspectives

The increasing knowledge of the mechanisms involved in metabolism is shifting the paradigms by which the pathophysiology of many pulmonary diseases is understood. Metabolic dysfunction is recognized in obesity-associated asthma, but other metabolic conditions have been shown to be independently related to asthma. Novel insights have also recently been brought by metabolomics in this filed. The purpose of this review is to discuss current perspectives regarding metabolic dysfunction in asthma, from obesity-related asthma to other metabolic conditions and the role of current pharmacological therapeutic strategies and lifestyle interventions. Obesity is a well-recognized risk factor for asthma across the lifespan, which is generally associated with poorer response to current available treatments, rendering a more severe, refractory disease status. Besides the epidemiological and clinical link, untargeted metabolomics studies have recently supported the obesity-associated asthma phenotype at the molecular level. Not only obesity-related, but also other aspects of metabolic dysregulation can be independently linked to asthma. These include hyperinsulinemia, dyslipidemia and hypertension, which need to be taken into account, even in the non-obese patient. Untargeted metabolomics studies have further highlighted several other metabolic pathways that can be altered in asthma, namely regarding oxidative stress and systemic inflammation, and also suggesting the importance of microbiota in asthma pathogenesis. Considering the reduced response to corticosteroids, other pharmacologic treatments have been shown to be effective regardless of body mass index. Non-pharmacologic treatments (namely weight reduction and dietary changes) may bring substantial benefit to the asthmatic patient. Taken together, this evidence points towards the need to improve our knowledge in this filed and, in particular, to address the influence of environmental factors in metabolic dysfunction and asthma development. Personalized medicine is definitely needed to optimize treatment, including a holistic view of the asthmatic patient in order to set accurate pharmacologic therapy together with dietary, physical exercise and lifestyle interventions.

Impaired Respiratory Function in Women With PCOS Compared With Matched Controls From a Population-Based Study

CONTEXT

Increased prevalence of asthma has been reported from epidemiological studies in women with polycystic ovary syndrome (PCOS).

OBJECTIVE

To investigate respiratory function in women with PCOS compared with controls in a clinical setting.

DESIGN

An 8-year clinical follow-up study including self-reported asthma diagnoses and spirometry of women with PCOS randomized to metformin or placebo during pregnancy in the original studies (the Pilot and the PregMet-study), compared with matched controls from a population-based cohort study (The HUNT Study).

SETTING

Secondary and tertiary care centers.

PARTICIPANTS

A total of 145 women with PCOS (54% of original cohort) were matched 1:3 to controls, on gender, age, and smoking-status.

MAIN OUTCOMES AND MEASURES

Self-reported doctor-diagnosed asthma (DDA), percentage of predicted forced expiratory volume in the first second of expiration (FEV1 % predicted), percentage of predicted forced vital capacity (FVC % predicted).

RESULTS

Women with PCOS reported more DDA compared with controls (19% vs 9%; P < 0.01). Spirometry indicated a combined obstructive (FEV1 % predicted, 93.7 vs 102.0; P < 0.01) and restrictive (FVC % predicted, 94.5 vs 103.7; P < 0.01) respiratory impairment in PCOS compared with controls. Metformin in pregnancy did not affect respiratory function at follow-up.

CONCLUSION

Women with PCOS reported higher prevalence of DDA compared with controls matched for age and smoking status. In addition, respiratory function was decreased, with both obstructive and restrictive components. Further insight to the underlying pathogenesis of these observations is needed.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: The PregMet study: NCT00159536. The Pilot study: NCT03259919.

Contemporary management techniques of asthma in obese patients

Introduction: Obesity-associated asthma represents a heterogeneous group of clinical phenotypes, including an adult-onset phenotype. These patients often have difficult to control symptoms and often are less likely to respond to conventional asthma therapies.Areas covered: This review covers the effects of lifestyle interventions, including diet and weight loss, effect asthma outcomes and how obesity-associated asthma responds to conventional approaches to asthma management.Expert opinion: Management of obesity-associated asthma should include lifestyle modifications aimed at weight reduction, management of other co-morbidities, and limiting systemic steroids. As many of these patients have non-Th2 asthma, long-acting muscarinic antagonists and macrolides may be potentially helpful. Medications to treat metabolic syndrome.