Glucagon-Like Peptide 1 Receptor Agonists and Chronic Lower Respiratory Disease Exacerbations Among Patients With Type 2 Diabetes

Association of Novel Antihyperglycemic Drugs Versus Metformin With a Decrease in Asthma Exacerbations

BACKGROUND

Similar to metformin, dipeptidyl peptidase-4 inhibitors (DPP-4 Is), glucagon-like peptidase 1 receptor agonists (GLP-1 RAs), and sodium glucose co-transporter-2 inhibitors (SGLT-2 Is) may improve control of asthma owing to their multiple potential mechanisms, including differential improvements in glycemic control, direct anti-inflammatory effects, and systemic changes in metabolism.

OBJECTIVE

To investigate whether these novel antihyperglycemic drugs were associated with fewer asthma exacerbations compared with metformin in patients with asthma comorbid with type 2 diabetes.

METHODS

Using a Japanese national administrative database, we constructed 3 active comparators-new user cohorts of 137,173 patients with a history of asthma starting the novel antihyperglycemic drugs and metformin between 2014 and 2022. Patient characteristics were balanced using overlap propensity score weighting. The primary outcome was the first exacerbation requiring systemic corticosteroids, and the secondary outcomes included the number of exacerbations requiring systemic corticosteroids.

RESULTS

DPP-4 Is and GLP-1 RAs were associated with a higher incidence of exacerbations requiring systemic corticosteroids compared with metformin (DPP-4 Is: 18.2 vs 17.4 per 100 person-years, hazard ratio: 1.09, 95% confidence interval [CI]: 1.05-1.14; GLP-1 RAs: 24.9 vs 19.0 per 100 person-years, hazard ratio: 1.14, 95% CI: 1.01-1.28). In contrast, the incidence of exacerbations requiring systemic corticosteroids was similar between the SGLT-2 Is and metformin groups (17.3 vs 18.1 per 100 person-years, hazard ratio: 1.00, 95% CI: 0.97-1.03). While DPP-4 Is and GLP-1 RAs were associated with more exacerbations requiring systemic corticosteroids, SGLT-2 Is were associated with slightly fewer exacerbations requiring systemic corticosteroids (53.7 vs 56.6 per 100 person-years, rate ratio: 0.95, 95% CI: 0.91-0.99).

CONCLUSIONS

While DPP-4 Is and GLP-1 RAs were associated with poorer control of asthma compared with metformin, SGLT-2 Is offered asthma control comparable to that of metformin.

Obesity-related asthma: new insights leading to a different approach

PURPOSE OF REVIEW

Obesity is a growing global health threat that significantly contributes to the burden of asthma by increasing the risk of developing asthma and exerting a distinct effect on lung function and inflammation. The treatment of obesity-related asthma is hindered by a poor response to standard asthma treatments, leading to worse asthma control. Weight loss strategies have a significant effect on asthma symptoms but are not feasible for a large proportion of patients, underscoring the need for a better understanding of the pathophysiology and the development of additional treatment options.

RECENT FINDINGS

Recent literature focusing on pathophysiology particularly delved into nontype 2 inflammatory mechanisms, associations with the metabolic syndrome and small airway impairment. Additionally, several new treatment options are currently investigated, including biologics, weight reduction interventions, and novel antiobesity drugs.

SUMMARY

Obesity-related asthma is a highly prevalent asthma phenotype for which weight loss strategies currently stand as the most specific treatment. Furthermore, novel pharmacological interventions aiming at metabolic processes are on the way.

Weight Loss Interventions for Adults With Obesity-Related Asthma

Obesity is a common asthma comorbidity in adults, contributing to higher patient morbidity and mortality. Conversely, weight loss can reduce the impact of obesity on asthma and improve patient outcomes by diverse mechanisms including modulating airway inflammation, reducing oxidative stress, and improving lung function. Multiple lifestyle, nonpharmacological, pharmacological, and surgical interventions are effective at reducing weight in the general population. Fewer have been studied specifically in the context of patients with asthma. However, increasingly effective pharmacologic options for weight loss highlight the need for allergists and pulmonologists to understand the range of approaches that may directly or indirectly yield clinical benefits in asthma management. Weight loss interventions often require multidisciplinary support to create strategies that can realistically achieve a patient's personalized asthma and weight goals. This includes minimizing the adverse weight effects of glucocorticoids, which remain a mainstay of asthma management. Disparities in access, cost, and insurance coverage of weight loss interventions remain acute challenges for providers and patients. Future studies are needed to elucidate mechanisms of action of specific weight loss interventions on short-term and long-term asthma outcomes.

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.

GLP-1 receptor agonists, SGLT2 inhibitors and noncardiovascular mortality in type 2 diabetes: Insights from a meta-analysis

OBJECTIVE

Type-2 diabetes (T2D) poses a higher risk of noncardiovascular mortality in addition to the burden of cardiovascular mortality. The well-established cardiovascular benefits of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2i) could solely explain their apparent effects on all-cause mortality in T2D. The present meta-analysis aims to pool their effects on noncardiovascular mortality in T2D and summarize the recent evidence on plausible pathways mediating these effects.

METHODS

PubMed, Embase, Web of Science, and clinical trial registries were searched for randomized controlled trials (RCTs) with ≥1-year duration in adults with T2D reporting both cardiovascular and all-cause mortality in treatment versus placebo arms (PROSPERO: CRD42022337559). Noncardiovascular mortality was calculated by subtracting cardiovascular mortality events from all-cause mortality and risk ratios (RRs) were calculated. Random-effects meta-analysis was done. GRADE framework was used to assess evidence quality.

RESULTS

We identified 17 eligible RCTs pooling data retrieved from 109,892 patients. Randomization to GLP-1 RA treatment versus placebo was associated with reduced noncardiovascular mortality (RR = 0.90; 95%CI: 0.81-0.99; I2 = 0 %; p < 0.05), consistent with their effects on cardiovascular mortality (RR = 0.88; 95%CI: 0.81-0.95; I2 = 0 %; p < 0.01) in T2D. Compared to placebo, SGLT2i significantly reduced noncardiovascular mortality (RR = 0.90; 95%CI: 0.82-0.99; I2 = 0 %; p < 0.05) along with cardiovascular mortality (RR = 0.84; 95%CI: 0.77-0.92; I2 = 28 %; p < 0.001). Subgroup analysis showed no significant effects of heart failure or renal function on treatment benefits of SGLT2i on noncardiovascular mortality (p value > 0.2 for subgroup differences).

CONCLUSION

The impact of GLP-1RAs and SGLT2i on mortality in people with T2D extends beyond their cardiovascular benefits.

Glucagon-like Peptide-1 Receptor Pathway Attenuates Platelet Activation in Aspirin-Exacerbated Respiratory Disease

Platelets are key contributors to allergic asthma and aspirin-exacerbated respiratory disease (AERD), an asthma phenotype involving platelet activation and IL-33-dependent mast cell activation. Human platelets express the glucagon-like peptide-1 receptor (GLP-1R). GLP-1R agonists decrease lung IL-33 release and airway hyperresponsiveness in mouse asthma models. We hypothesized that GLP-1R agonists reduce platelet activation and downstream platelet-mediated airway inflammation in AERD. GLP-1R expression on murine platelets was assessed using flow cytometry. We tested the effect of the GLP-1R agonist liraglutide on lysine-aspirin (Lys-ASA)-induced changes in airway resistance, and platelet-derived mediator release in a murine AERD model. We conducted a prospective cohort study comparing the effect of pretreatment with liraglutide or vehicle on thromboxane receptor agonist-induced in vitro activation of platelets from patients with AERD and nonasthmatic controls. GLP-1R expression was higher on murine platelets than on leukocytes. A single dose of liraglutide inhibited Lys-ASA-induced increases in airway resistance and decreased markers of platelet activation and recruitment to the lung in AERD-like mice. Liraglutide attenuated thromboxane receptor agonist-induced activation as measured by CXCL7 release in plasma from patients with AERD and CD62P expression in platelets from both patients with AERD (n = 31) and nonasthmatic, healthy controls (n = 11). Liraglutide, a Food and Drug Administration-approved GLP-1R agonist for treatment of type 2 diabetes and obesity, attenuates in vivo platelet activation in an AERD murine model and in vitro activation in human platelets in patients with and without AERD. These data advance the GLP-1R axis as a new target for platelet-mediated inflammation warranting further study in asthma.

Association of GLP-1 Receptor Agonists with Chronic Obstructive Pulmonary Disease Exacerbations among Patients with Type 2 Diabetes

Rationale: Patients with chronic obstructive pulmonary disease (COPD) and type 2 diabetes (T2D) have worse clinical outcomes compared with patients without metabolic dysregulation. GLP-1 (glucagon-like peptide 1) receptor agonists (GLP-1RAs) reduce asthma exacerbation risk and improve FVC in patients with COPD. Objectives: To determine whether GLP-1RA use is associated with reduced COPD exacerbation rates, and severe and moderate exacerbation risk, compared with other T2D therapies. Methods: A retrospective, observational, electronic health records-based study was conducted using an active comparator, new-user design of 1,642 patients with COPD in a U.S. health system from 2012 to 2022. The COPD cohort was identified using a previously validated machine learning algorithm that includes a natural language processing tool. Exposures were defined as prescriptions for GLP-1RAs (reference group), DPP-4 (dipeptidyl peptidase 4) inhibitors (DPP-4is), SGLT2 (sodium-glucose cotransporter 2) inhibitors, or sulfonylureas. Measurements and Main Results: Unadjusted COPD exacerbation counts were lower in GLP-1RA users. Adjusted exacerbation rates were significantly higher in DPP-4i (incidence rate ratio, 1.48 [95% confidence interval, 1.08-2.04]; P = 0.02) and sulfonylurea (incidence rate ratio, 2.09 [95% confidence interval, 1.62-2.69]; P < 0.0001) users compared with GLP-1RA users. GLP-1RA use was also associated with significantly reduced risk of severe exacerbations compared with DPP-4i and sulfonylurea use, and of moderate exacerbations compared with sulfonylurea use. After adjustment for clinical covariates, moderate exacerbation risk was also lower in GLP-1RA users compared with DPP-4i users. No statistically significant difference in exacerbation outcomes was seen between GLP-1RA and SGLT2 inhibitor users. Conclusions: Prospective studies of COPD exacerbations in patients with comorbid T2D are warranted. Additional research may elucidate the mechanisms underlying these observed associations with T2D medications.

A Road Map for Peer Review of Real-World Evidence Studies on Safety and Effectiveness of Treatments

The growing acceptance of real-world evidence (RWE) in clinical and regulatory decision-making, coupled with increasing availability of health care data and advances in automated analytic approaches, has contributed to a marked expansion of RWE studies of diabetes and other diseases. However, a recent spate of high-profile retractions highlights the need for improvements in the conduct of RWE research as well as in the associated peer review and editorial processes. We review best pharmacoepidemiologic practices and common pitfalls regarding design, measurement, analysis, data validity, appropriateness, and generalizability of RWE studies. To enhance RWE study assessments, we propose that journal editors require 1) study authors to complete RECORD-PE, a reporting guideline for pharmacoepidemiological studies on routinely collected data, 2) availability of predetermined study protocols and analysis plans, 3) inclusion of pharmacoepidemiologists on the peer review team, and 4) provision of detail on data provenance, characterization, and custodianship to facilitate assessment of the data source. We recognize that none of these steps guarantees a high-quality research study. Collectively, however, they permit an informed assessment of whether the study was adequately designed and conducted and whether the data source used was fit for purpose.

The relationship between the use of GLP-1 receptor agonists and the incidence of respiratory illness: a meta-analysis of randomized controlled trials

AIM

We aimed to assess the association between the use of Glucagon-like peptide-1 receptor agonists and the risk of 12 respiratory diseases in patients with type 2 diabetes, obesity, or overweight.

METHOD

The PubMed (MEDLINE), EMBASE, Cochrane Library, and ClinicalTrials.gov databases were searched from the establishment of the database to December 24, 2022. Dichotomous outcomes were analyzed using RR and 95% CI calculated from fixed-effects models.

RESULTS

Twenty-eight RCTs were ultimately included for analysis, involving a total of 77,485 participants. Compared to controls, patients with GLP-1RAs have a 14% lower risk of respiratory disease (RR 0.86, 95% CI 0.81-0.93 p < 0.0001), with Semaglutid (RR 0.82, 95% CI 0.68-0.97, p = 0.02), Liraglutide (RR 0.86. 95% CI 0.75-0.98, p = 0.03), Dulaglutide (RR 0.82, 95% CI 0.70-0.96, p = 0.02), Albiglutide (RR 0.93,95% CI 0.79-1.10, p = 0.40), Exenatide (RR 0.93, 95% CI 0.74-1.18, p = 0.55), Lixisenatide (RR 0.83, 95% CI 0.62-1.12, p = 0.22), and Efpeglenatide (RR 0.76, 95% CI 0.46-1.24, p = 0.27). Semaglutide, Liraglutide and Dulaglutide reduce the risk of respiratory diseases by 18%, 14% and 18%, respectively.Trial duration, control type, and indication were not associated with the impact of GLP-1 receptor agonists on overall respiratory disease. Among secondary outcomes, the risk of Pulmonary edema (RR 0.66, 95% CI 0.44-0.98, p = 0.04), and Bronchitis (RR 0.86, 95% CI 0.74-1.00, p = 0.04) was reduced.

CONCLUSION

In conclusion, GLP-1RAs were linked to a lower risk of overall respiratory diseases, especially Pulmonary edema and Bronchitis. In the future, physicians should pay attention to the relationship between GLP-1 RA and the risk of respiratory diseases and evaluate the efficacy of GLP-1RAs in the primary and secondary prevention of respiratory diseases. Trial registration CRD42023396138.

Reproducible variability: assessing investigator discordance across 9 research teams attempting to reproduce the same observational study

OBJECTIVE

Observational studies can impact patient care but must be robust and reproducible. Nonreproducibility is primarily caused by unclear reporting of design choices and analytic procedures. This study aimed to: (1) assess how the study logic described in an observational study could be interpreted by independent researchers and (2) quantify the impact of interpretations' variability on patient characteristics.

MATERIALS AND METHODS

Nine teams of highly qualified researchers reproduced a cohort from a study by Albogami et al. The teams were provided the clinical codes and access to the tools to create cohort definitions such that the only variable part was their logic choices. We executed teams' cohort definitions against the database and compared the number of subjects, patient overlap, and patient characteristics.

RESULTS

On average, the teams' interpretations fully aligned with the master implementation in 4 out of 10 inclusion criteria with at least 4 deviations per team. Cohorts' size varied from one-third of the master cohort size to 10 times the cohort size (2159-63 619 subjects compared to 6196 subjects). Median agreement was 9.4% (interquartile range 15.3-16.2%). The teams' cohorts significantly differed from the master implementation by at least 2 baseline characteristics, and most of the teams differed by at least 5.

CONCLUSIONS

Independent research teams attempting to reproduce the study based on its free-text description alone produce different implementations that vary in the population size and composition. Sharing analytical code supported by a common data model and open-source tools allows reproducing a study unambiguously thereby preserving initial design choices.

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.

Novel antihyperglycaemic drugs and prevention of chronic obstructive pulmonary disease exacerbations among patients with type 2 diabetes: population based cohort study

OBJECTIVE

To determine whether the use of glucagon-like peptide 1 (GLP-1) receptor agonists, dipeptidyl peptidase 4 (DPP-4) inhibitors, and sodium-glucose co-transporter-2 (SGLT-2) inhibitors, separately, is associated with a decreased risk of exacerbations of chronic obstructive pulmonary disease among patients with chronic obstructive pulmonary disease and type 2 diabetes.

DESIGN

Population based cohort study using an active comparator, new user design.

SETTING

The United Kingdom Clinical Practice Research Datalink linked with the Hospital Episode Statistics Admitted Patient Care and Office for National Statistics databases.

PARTICIPANTS

Three active comparator, new user cohorts of patients starting the study drugs (GLP-1 receptor agonists, DPP-4 inhibitors, or SGLT-2 inhibitors) or sulfonylureas with a history of chronic obstructive pulmonary disease. The first cohort included 1252 patients starting GLP-1 receptor agonists and 14 259 starting sulfonylureas, the second cohort included 8731 patients starting DPP-4 inhibitors and 18 204 starting sulfonylureas, and the third cohort included 2956 patients starting SGLT-2 inhibitors and 10 841 starting sulfonylureas.

MAIN OUTCOME MEASURES

Cox proportional hazards models with propensity score fine stratification weighting were fitted to estimate hazard ratios and 95% confidence intervals of severe exacerbation of chronic obstructive pulmonary disease (defined as hospital admission for chronic obstructive pulmonary disease), separately for GLP-1 receptor agonists, DPP-4 inhibitors, and SGLT-2 inhibitors. Whether these drugs were associated with a decreased risk of moderate exacerbation (defined as a co-prescription of an oral corticosteroid and an antibiotic along with an outpatient diagnosis of acute chronic obstructive pulmonary disease exacerbation on the same day) was also assessed.

RESULTS

Compared with sulfonylureas, GLP-1 receptor agonists were associated with a 30% decreased risk of severe exacerbation (3.5 v 5.0 events per 100 person years; hazard ratio 0.70, 95% confidence interval 0.49 to 0.99) and moderate exacerbation (0.63, 0.43 to 0.94). DPP-4 inhibitors were associated with a modestly decreased incidence of severe exacerbation (4.6 v. 5.1 events per 100 person years; hazard ratio 0.91, 0.82 to 1.02) and moderate exacerbation (0.93, 0.82 to 1.07), with confidence intervals including the null value. Finally, SGLT-2 inhibitors were associated with a 38% decreased risk of severe exacerbation (2.4 v 3.9 events per 100 person years; hazard ratio 0.62, 0.48 to 0.81) but not moderate exacerbation (1.02, 0.83 to 1.27).

CONCLUSIONS

In this population based study, GLP-1 receptor agonists and SGLT-2 inhibitors were associated with a reduced risk of severe exacerbations compared with sulfonylureas in patients with chronic obstructive pulmonary disease and type 2 diabetes. DPP-4 inhibitors were not clearly associated with a decreased risk of chronic obstructive pulmonary disease exacerbations.

Adjusting for indirectly measured confounding using large-scale propensity score

Confounding remains one of the major challenges to causal inference with observational data. This problem is paramount in medicine, where we would like to answer causal questions from large observational datasets like electronic health records (EHRs) and administrative claims. Modern medical data typically contain tens of thousands of covariates. Such a large set carries hope that many of the confounders are directly measured, and further hope that others are indirectly measured through their correlation with measured covariates. How can we exploit these large sets of covariates for causal inference? To help answer this question, this paper examines the performance of the large-scale propensity score (LSPS) approach on causal analysis of medical data. We demonstrate that LSPS may adjust for indirectly measured confounders by including tens of thousands of covariates that may be correlated with them. We present conditions under which LSPS removes bias due to indirectly measured confounders, and we show that LSPS may avoid bias when inadvertently adjusting for variables (like colliders) that otherwise can induce bias. We demonstrate the performance of LSPS with both simulated medical data and real medical data.

Evaluating the glucagon-like peptide-1 receptor in managing asthma

PURPOSE OF REVIEW

The aim of this study was to discuss the role of glucagon-like peptide-1 (GLP-1) receptor signalling in reducing lung inflammation and potential use for GLP-1 receptor agonists (GLP-1RAs) in management of asthma.

RECENT FINDINGS

Although GLP-1RA are currently used for the treatment of type 2 diabetes (T2D) and weight loss in obesity, there is much interest in expanding the indications for use in other diseases, including inflammatory pulmonary disease. In animal models of both acute and chronic pulmonary disease, use of GLP-1RA reduces airway inflammation, obstruction and fibrosis. In particular, GLP-1 receptor (GLP-1R) signalling seems to inhibit allergen-induced type 2 inflammation, making it an attractive agent for asthma. Results are especially promising in disease processes with disturbed metabolic regulation, such as T2D or metabolic syndrome. Retrospective clinical studies demonstrate promising evidence for the use of GLP-1RAs in comorbid diabetes and asthma, although prospective human studies are limited.

SUMMARY

Here, we discuss the biology of GLP-1 and GLP-1R signalling, review the preclinical and mechanistic evidence for how GLP-1R signalling may reduce pulmonary inflammation, and summarize recent and upcoming clinical studies. Ultimately, targeting GLP-1R signalling may represent a novel approach for asthma therapy that is glucocorticoid sparing and possibly disease modifying.

Medications and medical costs for diabetes patients with or without chronic respiratory disease in Beijing, China: A retrospective study

AIMS

The cost of drug regimens prescribed to Chinese patients has not been evaluated. This study aims to evaluate the medical costs and hypoglycemic agents for diabetes mellitus patients with or without chronic respiratory disease in Beijing, and to investigate the changes in the costs and number of antidiabetic medications used for diabetes patients with chronic respiratory disease from 2016 to 2018.

METHODS

This observational, retrospective study included diabetes patients with outpatient medication records from Beijing Medical Insurance between 2016 and 2018. The medications, including hypoglycemic and nonhypoglycemic drugs, insulin dosage, comorbidities, diabetes-related complications, treatment strategies, and annual medical costs, were recorded.

RESULTS

This study included 2,853,036 diabetes patients from 2016 to 2018. About 18.95%-20.53% of patients with chronic respiratory disease were predominantly distributed among those aged 45-84 years (88.7%-89.1%). Diabetes patients with chronic respiratory disease used more medications (4.48 ± 2.41 vs. 3.76 ± 2.33) and had higher total annual drug costs (¥12,286 ± 10,385 vs. ¥9700 ± 9202) to treat more comorbidities (2.52 ± 1.53 vs. 2.05 ± 1.85) than those without chronic respiratory disease (p <.0001, respectively). From 2016 to 2018, diabetes patients with chronic respiratory disease had a 4.2% increase in medication, a 1.9% decrease in comorbidities, and a 5.4% decrease in total annual drug costs.

CONCLUSIONS

In summary, diabetes patients with chronic respiratory disease had more comorbidities, required more hypoglycemic drugs, and had higher medical costs. During 2016-2018, diabetes patients with chronic respiratory disease used more medications and spent less money on medical care.