Bronchodilator response and lung function decline: Associations with exhaled nitric oxide with regard to sex and smoking status

Clinical utilization of airway inflammatory biomarkers in the prediction and monitoring of clinical outcomes in patients with chronic obstructive pulmonary disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) accounts for 545 million people living with chronic respiratory disorders and is the third leading cause of morbidity and mortality around the world. COPD is a progressive disease, characterized by episodes of acute worsening of symptoms such as cough, dyspnea, and sputum production.

AREAS COVERED

Airway inflammation is a prominent feature of COPD. Chronic airway inflammation results in airway structural remodeling and emphysema. Persistent airway inflammation is a treatable trait of COPD and plays a significant role in disease development and progression. In this review, the authors summarize the current and emerging biomarkers that reveal the heterogeneity of airway inflammation subtypes, clinical outcomes, and therapeutic response in COPD.

EXPERT OPINION

Airway inflammation can be broadly categorized as eosinophilic (type 2 inflammation) and non-eosinophilic (non-type 2 inflammation) in COPD. Currently, blood eosinophil counts are incorporated in clinical practice guidelines to identify COPD patients who are at a higher risk of exacerbations and lung function decline, and who are likely to respond to inhaled corticosteroids. As new therapeutics are being developed for the chronic management of COPD, it is essential to identify biomarkers that will predict treatment response.

Reduction of daily maintenance inhaled corticosteroids in patients with severe eosinophilic asthma treated with benralizumab (SHAMAL): a randomised, multicentre, open-label, phase 4 study

BACKGROUND

Stepwise intensification of inhaled corticosteroids (ICS) is routine for severe eosinophilic asthma, despite some poor responses to high-dose ICS. Dose reductions are recommended in patients responding to biologics, but little supporting safety evidence exists.

METHODS

SHAMAL was a phase 4, randomised, open-label, active-controlled study done at 22 study sites in four countries. Eligible participants were adults (aged ≥18 years) with severe eosinophilic asthma and a five-item Asthma Control Questionnaire score below 1·5 and who received at least three consecutive doses of benralizumab before screening. We randomly assigned patients (3:1) to taper their high-dose ICS to a medium-dose, low-dose, and as-needed dose (reduction group) or continue (reference group) their ICS-formoterol therapy for 32 weeks, followed by a 16-week maintenance period. The primary endpoint was the proportion of patients reducing their ICS-formoterol dose by week 32. The primary outcome was assessed in the reduction group, and safety analyses included all randomly assigned patients receiving study treatment. This study is registered at ClinicalTrials.gov, NCT04159519.

FINDINGS

Between Nov 12, 2019, and Feb 16, 2023, we screened and enrolled in the run-in period 208 patients. We randomly assigned 168 (81%) to the reduction (n=125 [74%]) and reference arms (n=43 [26%]). Overall, 110 (92%) patients reduced their ICS-formoterol dose: 18 (15%) to medium-dose, 20 (17%) to low-dose, and 72 (61%) to as-needed only. In 113 (96%) patients, reductions were maintained to week 48; 114 (91%) of patients in the reduction group had zero exacerbations during tapering. Rates of adverse events were similar between groups. 91 (73%) patients had adverse events in the reduction group and 35 (83%) in the reference group. 17 patients had serious adverse events in the study: 12 (10%) in the reduction group and five (12%) in the reference group. No deaths occurred during the study.

INTERPRETATION

These findings show that patients controlled on benralizumab can have meaningful reductions in ICS therapy while maintaining asthma control.

FUNDING

AstraZeneca.

[Effects of type 2 inflammation on bronchodilator responsiveness of large and small airways in chronic obstructive pulmonary disease]

OBJECTIVE

To investigate the impact of type 2 inflammation markers blood eosinophils (EOS) and fractional exhaled nitric oxide (FeNO) on bronchodilator responsiveness (BDR) in patients with chronic obstructive pulmonary disease (COPD).

METHODS

This study was conducted among 389 patients with an established diagnosis of COPD in our hospital from October, 2019 to October, 2023, who all underwent bronchial dilation test (BDT) of the large and small airways. Based on smoking history, blood EOS, and FeNO, these patients were divided group A (blood EOS < 300/μL + FeNO < 35 ppb + smoking history < 20 pack-years), group B (blood EOS < 300/μL+FeNO < 35 ppb+smoking history ≥20 pack-years), group C (blood EOS ≥300/μL or FeNO≥35 ppb+smoking history ≥20 pack-years), and group D (blood EOS ≥300/μL or FeNO ≥35 ppb+smoking history < 20 pack-years) for analyzing the relationship between clinical indexes and BDR.

RESULTS

BDR evaluation based on forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and maximum mid-expiratory flow (MMEF) yielded consistent results, all showing a younger mean age, higher FeNO levels, and higher blood EOS counts and percentages in patients positive for BDT (P < 0.05). The improvement value and improvement rate of FEV1 were significantly lower in group A than in group D. The improvement value and improvement rate of FEV1 as well as the improvement rate of MMEF were significantly lower in group B than in group D. In the overall patients, age and FeNO were significantly correlated with the improvement value and improvement rate of FEV1 and the improvement rate of MMEF (P < 0.05).

CONCLUSION

Type 2 inflammation markers have different effects on BDR in the large and small airways of COPD patients, and their clinical significance needs further investigation.

Antioxidant Intake and Biomarkers of Asthma in Relation to Smoking Status-A Review

Asthma is considered a chronic inflammatory disorder associated with airway hyperresponsiveness (AHR). Increased oxidative stress (OS) is a clinical feature of asthma, which promotes the inflammatory responses in bronchial/airway epithelial cells. Smokers and nonsmokers with asthma have been shown to have increases in several OS and inflammatory biomarkers. However, studies suggest significant differences in OS and inflammation biomarkers between smokers and nonsmokers. A few studies suggest associations between antioxidant intake from diet/supplements and asthma in patients with different smoking status. Evidence is lacking on the protective role of antioxidant vitamin and/or mineral consumption against asthma by smoking status with respect to inflammation and OS biomarkers. Therefore, the aim of this review is to highlight current knowledge regarding the relations between antioxidant intake, asthma, and its associated biomarkers, according to smoking status. This paper can be used to guide future research directions towards the health consequences of antioxidant intake in smoking and nonsmoking asthmatics.

Toward a Predict and Prevent Approach in Obstructive Airway Diseases

Asthma and chronic obstructive pulmonary disease are currently diagnosed and treated after the demonstration of variable airflow limitation and symptoms. Under this framework, undiagnosed and unchecked airway inflammation is associated with recurrent acute attacks, airway remodeling, airflow limitation, adverse effects of corticosteroids, and impaired quality of life, ultimately leading to the collection of side effects termed "people remodeling." This one-size-fits-all damage control approach aims to control symptoms and treat exacerbations rather than modify the underlying disease process. The advent of highly effective therapies targeting proximal drivers of airway inflammation calls for a paradigm shift; upstream-acting therapies offer potential to alter the disease course and achieve clinical remission. We propose moving away from downstream firefighting and toward a "predict and prevent" model, measuring inflammation and providing anti-inflammatory therapy early, without waiting for further clinical deterioration. Much in the same way that high blood pressure and cholesterol are used to predict and prevent heart attacks, in asthma, elevated blood eosinophils and/or exhaled nitric oxide can be used to predict and prevent asthma attacks. We also advocate moving research further upstream by identifying patients with subclinical airway inflammation or disease who may be at risk of progressing to airflow limitation and associated morbidities and intervening early to prevent them. In summary, we call for a predict and prevent approach in obstructive airway disease.

Sex differences of small airway function and fractional exhaled nitric oxide in patients with mild asthma

BACKGROUND

Sex differences of small airway function (SAF) and fractional exhaled nitric oxide (FeNO) in patients with mild asthma remain unclear.

OBJECTIVE

To evaluate sex differences of SAF and FeNO in patients with mild asthma confirmed by positive methacholine challenge test (MCT) result.

METHODS

This cross-sectional, double-centered, observational study enrolled 1609 adult patients with forced expiratory volume in 1 second greater than or equal to 80% and suspected asthma symptoms. Data of spirometry, FeNO, impulse oscillometry measurements, and peripheral blood test result were compared between males and females. The receiver-operating characteristic curves of SAF parameters and FeNO in predicting positive MCT result were also calculated.

RESULTS

In patients with mild asthma matched by age, males had better SAF but higher FeNO levels than females (60 [29.27%] vs 187 [46.75%] for small airway dysfunction, 78.6% vs 72.0% for forced expiratory flow [FEF]_50%, 67.5% vs 60.1% for FEF_75%, 73.7% vs 67.4% for FEF_25%-75%, and 42.0 ppb vs 29.0 ppb for FeNO, respectively, all P ≤ .001). The FeNO levels in male current smokers were considerably lower than those of nonsmokers. SAF and FeNO values declined more rapidly with age among female than male patients with asthma. The optimal cutoff values of FEF_25%-75%, FEF_50%, and FeNO for predicting a positive MCT result were 81.5%, 86.4%, and 41.0 ppb in males vs 73.7%, 76.9%, and 35.0 ppb in females.

CONCLUSION

In patients with mild asthma, the female patients have worse SAF, lower FeNO levels, and a more prominent decline trend of those parameters with age than males. Sex-specific cutoff values should be considered when SAF parameters (FEF_25%-75%, FEF_50%), alone or combined with FeNO, are used to predict positive MCT result in asthma diagnosis.

Sex differences in adult asthma and COPD therapy: a systematic review

Background

Although asthma is more prevalent in women and the prevalence of COPD is increasing in women, the current international recommendations for the management and prevention of asthma and COPD provide no sex-related indication for the treatment of these diseases. Therefore, we systematically reviewed the evidence across literature on the sex-related effectiveness of asthma and COPD therapy.

Methods

This systematic review has been registered in PROSPERO and performed according to PRISMA-P. The PICO framework was applied for the literature search strategy: "patient problem” included adult patients suffering from asthma or COPD, “Intervention” regarded the pharmacological treatments for asthma or COPD, “Comparison” was vs. baseline, active controls, or placebo, “Outcome” was any difference sex-related in the effectiveness of interventions.

Results

In asthma 44% of the evidence reported that men responded better than women to the therapy, whereas this percentage was 28% in COPD. ICS was generally less effective in women than in men to treat asthma, and consistent evidence suggests that in asthmatic patients ICS/LABA/LAMA combination may be equally effective in both men and women. Due to the inconsistent available evidence, it is not possible to identify specific treatments whose effectiveness is related to sex difference in COPD patients.

Conclusions

There is a strong need of investigating the sex-related impact of asthma and COPD treatments. Pre-specified analyses in men and women should be planned in future trial protocols, a necessary condition that should be requested also by the regulatory agencies to overcome the anachronistic “one-size-fits-all” approach to therapeutics associated with suboptimal outcomes for patients.

FeNO in Asthma

Asthma is a common disease affecting 350 million people worldwide, which is characterized by airways inflammation and hyperreactivity. Historically diagnosis and treatment have been mainly based on symptoms, which have the potential to result in misdiagnosis and inappropriate treatment. Nitric oxide (NO) is exhaled in human breath and is a marker of airways inflammation. Levels of NO are increased in the exhaled breath of patients with type 2 asthma and fractional exhaled nitric oxide (FeNO) provides an objective biomarker of airway inflammation. FeNO testing is an accessible, noninvasive, and easy-to-use test. Cut-off values have been established by the American Thoracic Society (ATS), the Global Initiative for Asthma (GINA), and the National Institute for Health and Care Excellence (NICE) but vary between guidance. FeNO levels have been shown to be predictive of blood and sputum eosinophil levels but should not be used in isolation and current guidance emphasizes the importance of incorporating clinical symptoms and testing when utilizing FeNO results. The inclusion of FeNO testing can increase diagnostic accuracy of asthma, while high levels in asthmatic patients can help predict response to inhaled corticosteroids (ICS) and suppression of levels with ICS to monitor adherence. FeNO levels are also a predictor of asthma risk with increased exacerbation rates and accelerated decline in lung function associated with high levels as well as having an emerging role in predicting response to some biologic therapies in severe asthma. FeNO testing is cost-effective and has been shown, when combined with clinical assessment, to improve asthma management.