Clinical Outcomes in People with Difficult-to-Control Asthma Using Electronic Monitoring to Support Medication Adherence

Change is in the air: key questions on the 'Treatable Traits' model for chronic airway diseases in primary care

Despite great advancements in the treatment of chronic airway diseases, improvements in morbidity and mortality have stalled in recent years. Asthma and chronic obstructive pulmonary disease are complex and heterogeneous diseases that require tailored management based on individual patient characteristics and needs. The Treatable Traits (TTs) approach aims to personalise and improve patient care through the identification and targeting of clinically relevant and modifiable pulmonary, extra-pulmonary and behavioural traits. In this article, we outline the rationale for TTs-based management and provide practical guidance for its application in primary care. To aid implementation, seven potential 'prime' traits are proposed: airflow obstruction, eosinophilic inflammation, adherence, inhaler technique, smoking, low body mass index/obesity and anxiety and depression-selected for their prevalence, recognisability and feasibility of use. Some of the key questions among healthcare professionals, that may be roadblocks to widespread application of a TTs model of care, are also addressed.

Assessing Inhaled Corticosteroid Adherence and Responsiveness in Severe Asthma Using Beclometasone Dipropionate/Formoterol NEXThaler Dose-Counting and Nitric Oxide Monitoring

BACKGROUND

Sixty-five percent of people with severe asthma and a fractional exhaled nitric oxide (Feno) greater than or equal to 45 parts per billion (ppb) are nonadherent to inhaled corticosteroids (ICSs). Digital devices recording both time of use and inhaler technique identify nonadherence and ICS responsiveness but are not widely available. As the NEXThaler dose counter activates only at an inspiratory flow rate of 35 L/min, this may provide an alternative to identifying ICS responsiveness.

OBJECTIVE

To assess ICS adherence and responsiveness in severe asthma using beclometasone/formoterol (200/6 μg) NEXThaler (BFN) dose-counting.

METHODS

Patients with severe asthma with a Feno greater than or equal to 45 ppb were invited to use BFN in place of their usual ICS/long-acting β2-agonist. Feno, 6-item Asthma Control Questionnaire score, lung function, and blood eosinophil count were monitored for 3 months. A log10ΔFeno of greater than or equal to 0.24 was used to define Feno suppression as the primary marker of ICS responsiveness at day 28.

RESULTS

Twenty-seven of 48 (56%) patients demonstrated significant Feno suppression at month 1 (median pre-114, post-48 ppb, P < .001). A small but significant reduction occurred in Feno nonsuppressors. The 6-item Asthma Control Questionnaire score fell a median 1.2 units in Feno suppressors (P < .001) and 0.5 units in nonsuppressors (P = .025). These effects were sustained until month 3 in Feno suppressors, with a significant improvement in FEV1 and blood eosinophils. Sixty-seven percent (18 of 27) of those with baseline ICS/long-acting β2-agonist prescription refills of 80% or more were Feno suppressors, suggesting prior nonadherence despite adequate prescription collection. Seventy-nine percent of Feno suppressors did not require biologics within mean 11.4 months from initial dose counting.

CONCLUSIONS

BFN dose-counting identifies ICS responsiveness in severe asthma with the implication that these patients may not need to progress to biological therapies.

Digital inhalers for asthma management

PURPOSE OF REVIEW

Although digital inhaler systems for asthma management have been commercially available for over a decade, their current use in clinical practice is limited. This review outlines barriers and offers potential solutions to their implementation.

RECENT FINDINGS

Digital inhaler systems demonstrate increased controller medication adherence, decreased quick-relief medication use, and improved asthma control.

SUMMARY

Use of digital inhaler systems is supported by data from large clinical trials demonstrating improved asthma outcomes. Navigating telemedicine during the coronavirus disease 2019 pandemic has led to advances clearing the path for increased adoption of digital inhaler systems. Progress in areas including patient education and onboarding, clinical management, coding and billing, privacy and security have facilitated implementation in clinical practice.

Digitally monitored inhaled therapy: a 'smart' way to manage severe asthma?

INTRODUCTION

One of the fundamental challenges of managing patients with severe asthma is treatment adherence, particularly with inhaled corticosteroids. Adherence is difficult to measure objectively and poor adherence is associated with worse outcomes. In this study, assess the ability of a 'smart' inhaler to record adherence in severe asthma patients and measure the impact of this on asthma control.

METHODS

Consecutive consenting patients meeting criteria for biologics had their existing high-dose ICS/LABA//LAMA combination inhaler/s switched to mometasone/indacaterol/glycopyrronium (114/46/136). Routine clinical data, including blood eosinophils, FeNO, and ACQ-6 scores were collected at baseline and at 4 wk. Adherence was then checked on the Propeller Health app, and good adherence was defined as >80% of prescribed usage. Participants were then followed-up at 12 months to record the proportion of patients who were initiated on biologics.

RESULTS

77 patients (mean [SD] age = 50.4 [15.7] years, 67.5% female [n = 52]) participated. 71 participants were able to use the device and 65% (n = 46) of these attained good asthma control and were not initiated on biologics at 12-month follow-up. Both groups demonstrated a significant reduction in ACQ6 score at follow-up (2.81 vs. 1.92, p < 0.001 and 3.05 vs. 2.60, p < 0.001, respectively), but there was no statistically significant difference in improvement between groups. Patients with optimal adherence also demonstrated a significant reduction in median FeNO at follow-up (47 ppb vs. 40 ppb, p = 0.003).

CONCLUSIONS

In severe asthma patients, 'smart' inhalers may represent an effective management tool to improve adherence and asthma control, therefore avoiding the need for patients to commence biological therapies.

Cost-Effectiveness of Fractional Exhaled Nitric Oxide Suppression Testing as an Adherence Screening Tool Among Patients With Difficult-to-Control Asthma

BACKGROUND

Approximately 50% of adults on long-term asthma medication are nonadherent. Current methods to detect nonadherence have had limited effect. Fractional exhaled nitric oxide suppression testing (FeNOSuppT) has demonstrated clinical effectiveness as an adherence screening tool to detect poor adherence to inhaled corticosteroids in difficult-to-control asthma prior to initiation of expensive biologic therapy.

OBJECTIVE

Estimate the cost effectiveness and budget impact of FeNOSuppT as a screen prior to the initiation of biologic therapy among U.S. adults with difficult-to-control asthma and high fractional exhaled nitric oxide (≥45 ppb).

METHODS

A decision tree simulated the progression of a cohort of patients over a 1-year time horizon into 1 of 3 states ([1] discharged from or [2] remain in specialist care; or [3] progress to biologics). Two strategies, with and without FeNOSuppT, were examined and the incremental net monetary benefit estimated using a discount rate of 3% and a willingness-to-pay threshold of $100,000 per quality-adjusted life year (QALY). Sensitivity analysis and a budget impact analysis were also undertaken.

RESULTS

In the baseline scenario, FeNOSuppT prior to the initiation of biologic therapy was associated with lower costs ($4,435/patient) and fewer QALYs (0.0023 QALY/patient) compared with no FeNOSuppT over 1 year and was considered cost effective (incremental net monetary benefit = $4,207). The FeNOSuppT was consistently found to be cost effective across a range of scenarios and in deterministic and probabilistic sensitivity analyses. Assuming differential levels of FeNOSuppT uptake (20%-100%), this was associated with budget savings ranging from USD $5 million to $27 million.

CONCLUSIONS

The FeNOSuppT is likely to be cost effective as a protocol-driven, objective, biomarker-based tool for identifying nonadherence in difficult-to-control asthma. This cost effectiveness is driven by cost savings from patients not progressing to expensive biologic therapy.

Clinical Impact of Electronic Monitoring Devices of Inhalers in Adults with Asthma or COPD: A Systematic Review and Meta-Analysis

We conducted a systematic review and meta-analysis to gain insight into the characteristics and clinical impact of electronic monitoring devices of inhalers (EMDs) and their clinical interventions in adult patients with asthma or COPD. The search included PubMed, Web of Science, Cochrane, Scopus and Embase databases, as well as official EMDs websites. We found eight observational studies and ten clinical trials, assessing a wide range of clinical outcomes. Results from the meta-analysis on adherence to inhalers in a period over three months were favourable in the EMD group (fixed effects model: SMD: 0.36 [0.25–0.48]; random effects model SMD: 0.41 [0.22–0.60]). An exploratory meta-analysis found an improvement in ACT score (fixed effect model SMD: 0.25 [0.11–0.39]; random effects model: SMD: 0.47 [−0.14–1.08]). Other clinical outcomes showed mixed results in the descriptive analyses. The findings of this review highlight the benefits of EMDs in the optimization of adherence to inhaled therapy as well as the potential interest in other clinical outcomes.

Management of difficult-to-treat asthma in adolescence and young adults

The period of adolescence and young adulthood (AYA) has been proposed to extend from 11 to 25 years of age as patients in this age group face similar challenges. AYA is a time of fast and great physiological and psychological growth, in which an individual transitions from a young dependent child to a mature independent adult. Behaviour patterns during adolescence, such as risk taking and desire for privacy, can challenge parents or healthcare professionals' (HCPs') ability to help adolescents to manage their asthma.

Asthma itself tends to remit, become milder or worsen into a severe variant during adolescence. The pre-pubertal male predominance of asthma switches to a female predominance in late teen years. ∼10% of AYA with asthma have “difficult-to-treat asthma (DTA)”, characterised by poor asthma control despite treatment with inhaled corticosteroids (ICS) and other controller medications. DTA management in AYA requires a multidisciplinary team approach and systematic assessment that can address the key questions of objective confirmation of diagnosis, severity assessment, phenotyping, comorbidities, asthma mimickers or other drivers of poor control such as non-adherence to treatment.

A key task for HCPs is to establish the magnitude of the severe asthma componentversusother non-asthma drivers of symptoms (e.g.inducible laryngeal obstruction or breathing pattern disorder). Severe asthma is a subset of DTA and is determined once asthma diagnosis and its severity have been confirmed and adherence to controller (ICS) treatment has been assured. Severe asthma is a heterogeneous disease and appropriate phenotyping is necessary for the management of treatable traits and consideration for biologic therapies.

Finally, an important part of successful management of DTA in the AYA group is the provision of an effective transition of asthma care from paediatric to adult asthma services through setting up a well-designed asthma transition pathway tailored to the individual patient needs.

Interval change in fractional exhaled nitric oxide (FENO) reflects short-term change in adherence following electronic inhaler reminders

BACKGROUND

In asthma, suppression of fractional exhaled nitric oxide (FENO) is a marker of adherence in the short-term. The usefulness of FENO to indicate change in adherence in the longer term is unknown. The aims of this study were to determine the relationship between changes in adherence and corresponding changes in FENO over short (1 week) and long-term (3 month) periods.

METHODS

After establishing initial ICS adherence using electronic inhaler monitor (EIM) devices, reminders were switched on for 1 week ('short-term') to optimize adherence. Reminders were then switched off and patients followed up after 3 months ('long-term'). FENO was measured at the start and end of each period. Using linear regression, we analyzed change in FENO in relation to change in adherence.

RESULTS

Forty-two patients contributed complete data for analysis. In the short-term, change in adherence was independently associated with change in FENO (β = -0.36, p = 0.036) even after adjusting for initial adherence and ICS dose. The higher the initial FENO, the greater the decline in FENO with improved adherence. This relationship between change in adherence and change in FENO was not observed in the long-term.

CONCLUSION

Change in adherence over 1 week following the use of EIM reminders independently predicted change in FENO. This relationship was not maintained at 3 months.

Progress in diagnosis and treatment of difficult-to-treat asthma in children

At present, medications containing inhaled corticosteroids (ICS-containing) are the keystones of asthma treatment. The majority of asthmatic children can significantly improve clinical outcomes with little worsening by standardized inhaled glucocorticoid treatment, but there is still a small proportion of children who are unable to achieve good symptom control even after the maximum standardized treatment, known as 'children with difficult-to-treat asthma (DA)'. The high heterogeneity of DA makes therapy challenging and expensive, which poses a serious risk to children's health and makes it extremely difficult for clinical physicians to accurately identify and treat children with DA. This article reviews the definition, evaluation, and treatment of this asthma in order to provide a reference for optimal clinical decision-making.

Advancing Digital Solutions to Overcome Longstanding Barriers in Asthma and COPD Management

Maintenance therapy delivered via inhaler is central to asthma and chronic obstructive pulmonary disease (COPD) management. Poor adherence to inhaled medication and errors in inhalation technique have long represented major barriers to the optimal management of these chronic conditions. Technological innovations may provide a means of overcoming these barriers. This narrative review examines ongoing advances in digital technologies relevant to asthma and COPD with the potential to inform clinical decision-making and improve patient care. Digital inhaler devices linked to mobile apps can help bring about changes in patients' behaviors and attitudes towards disease management, particularly when they build in elements of interactivity and gamification. They can also support ongoing technique education, empowering patients and helping providers maximize the value of consultations and develop effective action plans informed by insights into the patient's inhaler use patterns and their respiratory health. When combined with innovative techniques such as machine learning, digital devices have the potential to predict exacerbations and prompt pre-emptive intervention. Finally, digital devices may support an advanced precision medicine approach to respiratory disease management and help support shared decision-making. Further work is needed to increase uptake of digital devices and integrate their use into care pathways before their full potential in personalized asthma and COPD management can be realized.

Integrating digital inhalers into clinical care of patients with asthma and chronic obstructive pulmonary disease

Modernizing inhaled medications through digital technology can help address persistent problems of non-adherence and poor inhaler technique in patients with obstructive lung diseases. With a growing body of supportive clinical studies, advances in digital inhaler sensors and platforms, greater support from payers and healthcare organizations, significant growth with these technologies is expected. While all digital (smart) inhalers record adherence, these are distinguished by their compatibility with commercial inhalers, capabilities to guide inhaler technique, use of patient-reported outcomes, and user-friendliness for both the healthcare professional (HCP) and patient. Due to the complexity and novelty of employing digital inhalers, collaboration with multiple entities within health systems is necessary and a well-planned integration is needed. For HCPs and patients, cybersecurity and privacy are critical, it will require review by each healthcare organization. In the US, some payers reimburse for remote monitoring using digital inhalers, but reimbursement is currently unavailable in other countries. There are several models for remote patient care, as employing an active, ongoing digital interface between the HCP and patient or they may choose to only review data at clinical encounters. Personalization of therapies and feedback are key to success. While digital inhaler malfunction uncommonly occurs, patient attrition over a year is significant. Some patients will be challenged to use digital platforms or have the necessary technology. Additional research is needed to address cost-effectiveness, in vivo accuracy of inspiratory measurement capable devices, ability to teach inhaler technique, their application for monitoring lung function, and lastly real-world adoption and implementation in routine clinical practice.

Airway remodelling rather than cellular infiltration characterizes both type2 cytokine biomarker-high and -low severe asthma

BACKGROUND

The most recognizable phenotype of severe asthma comprises people who are blood eosinophil and FeNO-high, driven by type 2 (T2) cytokine biology, which responds to targeted biological therapies. However, in many people with severe asthma, these T2 biomarkers are suppressed but poorly controlled asthma persists. The mechanisms driving asthma in the absence of T2 biology are poorly understood.

OBJECTIVES

To explore airway pathology in T2 biomarker-high and -low severe asthma.

METHODS

T2 biomarker-high severe asthma (T2-high, n = 17) was compared with biomarker-intermediate (T2-intermediate, n = 21) and biomarker-low (T2-low, n = 20) severe asthma and healthy controls (n = 28). Bronchoscopy samples were processed for immunohistochemistry, and sputum for cytokines, PGD2 and LTE4 measurements.

RESULTS

Tissue eosinophil, neutrophil and mast cell counts were similar across severe asthma phenotypes and not increased when compared to healthy controls. In contrast, the remodelling features of airway smooth muscle mass and MUC5AC expression were increased in all asthma groups compared with health, but similar across asthma subgroups. Submucosal glands were increased in T2-intermediate and T2-low asthma. In spite of similar tissue cellular inflammation, sputum IL-4, IL-5 and CCL26 were increased in T2-high versus T2-low asthma, and several further T2-associated cytokines, PGD2 and LTE4 , were increased in T2-high and T2-intermediate asthma compared with healthy controls.

CONCLUSIONS

Eosinophilic tissue inflammation within proximal airways is suppressed in T2 biomarker-high and T2-low severe asthma, but inflammatory and structural cell activation is present, with sputum T2-associated cytokines highest in T2 biomarker-high patients. Airway remodelling persists and may be important for residual disease expression beyond eosinophilic exacerbations. Registered at ClincialTrials.gov: NCT02883530.

Digital Inhalers and Remote Patient Monitoring for Asthma

Digital inhaler systems, remote patient monitoring, and remote therapeutic monitoring offer great promise as diagnostic tools and therapeutic interventions to improve adherence and inhaler technique for patients with difficult-to-control asthma. In turn, improvements in adherence and inhaler technique may translate into decreasing the need for high side effect treatments such as oral corticosteroids and costly therapies including biologics. Although more clinical trials are needed, studies that use digital inhaler systems to collect objective real-time data on medication-taking behavior via electronic medication monitors and feed this data back to patients on their mobile asthma app, and to health care professionals on the clinician dashboard to counsel patients, show positive outcomes. This article addresses the use of these diagnostic and therapeutic tools in asthma care, how to choose a digital inhaler system, how to teach patients to use the system, strategies for the adoption of these technologies in large health care systems as well as smaller practices, coding and reimbursement, liability concerns, and research gaps.

Longitudinal changes in sputum and blood inflammatory mediators during FeNO suppression testing

To explore whether fractional exhaled nitric oxide (FeNO) non-suppression identifies corticosteroid resistance, we analysed inflammatory mediator changes during a FeNO suppression test with monitored high-intensity corticosteroid therapy. In linear mixed-effects models analysed over time, the 15 clinically distinct 'suppressors' (ie, ≥42% FeNO suppression) normalised Asthma Control Questionnaire scores (mean±SD, start to end of test: 2.8±1.4 to 1.4±0.9, p<0.0001) and sputum eosinophil counts (median (IQR), start to end of test: 29% (6%-41%) to 1% (1%-5%), p=0.0003) while significantly decreasing sputum prostaglandin D2 (254 (89-894) to 93 (49-209) pg/mL, p=0.004) and numerically decreasing other type-2 cytokine, chemokine and alarmin levels. In comparison, the 19 non-suppressors had persistent sputum eosinophilia (10% (1%-67%) despite high-intensity therapy) with raised end-test inflammatory mediator levels (1.9 (0.9-2.8)-fold greater than suppressors). FeNO non-suppression during monitored treatment implies biological corticosteroid resistance.

Assessing adherence to inhaled therapies in asthma and the emergence of electronic monitoring devices

Infrequent use of inhaled corticosteroids (ICS) and/or over-reliance of short-acting β-agonists (SABA) are recognised as key contributors to increased morbidity and mortality in asthma. The most frequent measures of ICS adherence and SABA use rely on patient-reported questionnaires or prescription refill records, neither of which are considered sufficiently reliable. Technological advancements in the development of electronic monitoring of inhaler devices allow for monitoring of use, as well as recording of and feedback on inhaler technique for some devices. Most electronic monitoring devices (EMDs) are paired with a smartphone application, allowing patients to set reminders and display both preventer and reliever use over time. This allows identification of intentional and unintentional ICS non-adherence as well as frequency of SABA use. This information assists clinicians in distinguishing difficult-to-control from severe asthma. Although additional evidence is required to assess the impact of EMDs on clinical outcome measures such as exacerbation rate, the introduction of EMDs into the asthma armoury is a significant step forward in asthma care with the potential to improve asthma-related outcomes.

Electronic Inhaler Monitoring for Chronic Airway Disease: Development and Application of a Multidimensional Efficacy Framework

Inhaled therapy is the cornerstone of chronic airway disease therapy, but poor adherence to controller inhalers worsens clinical outcomes and increases cost. Monitoring of controller use is needed to improve adherence, and monitoring of reliever use can predict impending exacerbations. Both can be accurately achieved by electronic inhaler monitoring (EIM). However, evidence for EIM use in clinical practice is limited and varied, and knowledge gaps remain across different outcomes and health settings. We aimed to develop a framework to assess EIM systematically across all aspects of efficacy, apply this framework to the current literature, and identify gaps in efficacy to inform future development in the field. We adapted an existing framework for diagnostic tests, consisting of six levels of efficacy with ascending clinical relevance: technical, diagnostic accuracy, diagnostic thinking, therapeutic, patient outcome, and societal efficacy. Tailoring this framework to EIM, we incorporated expert feedback and applied it to the EIM efficacy literature. We found that EIM has good diagnostic accuracy, diagnostic thinking, and therapeutic efficacies, but evidence is lacking for specific aspects of technical, patient outcome, and societal efficacies. Further development of EIM requires improved reliability, usability, and data security for patients, and optimal integration with electronic medical records and overall patient care. Defining appropriate target patient groups and pairing EIM data with effective interventions, in conjunction with reducing costs through technological innovation and economies of scale, will enhance patient and societal outcome efficacies.

Using FeNO Measurement in Clinical Asthma Management

Asthma is a common and heterogeneous disease, characterised by lower airway inflammation and airflow limitation. Critical factors in asthma management include establishing an accurate diagnosis and ensuring appropriate selection and dosage of anti-inflammatory therapies. The majority of asthma patients exhibit type 2 (T2) inflammation, with increased interleukin (IL)-4, IL-5, and IL-13 signalling, often with associated eosinophilia. Identifying lower airway eosinophilia with sputum induction improves asthma outcomes, but is time consuming and costly. Increased T2-inflammation leads to upregulation of nitric oxide (NO) release into the airway, with increasing fractional exhaled NO (FeNO) reflecting greater T2-inflammation. FeNO can be easily and quickly measured in the clinic, offering a point of care surrogate measure of the degree of lower airway inflammation. FeNO testing can be used to help confirm an asthma diagnosis, to guide inhaled corticosteroid therapy, to assess adherence to treatment, and to aid selection of appropriate biologic therapy. However, FeNO levels may also be influenced by a variety of intrinsic and extrinsic factors other than asthma, including nasal polyposis and cigarette smoking, and must be interpreted in the broader clinical context rather than viewed in isolation. This review discusses the clinical application of FeNO measurement in asthma care, from diagnosis to treatment selection, and describes its place in current international expert guidelines.

Utility of fractional exhaled nitric oxide suppression as a prediction tool for progression to biologic therapy

Rationale

The utility of fractional exhaled nitric oxide (F _ENO) suppression (FeNOSuppT) to identify non-adherence to inhaled corticosteroid (ICS) treatment has previously been reported, but whether it can predict clinical outcome remains unclear.

Objectives

We examined the utility of FeNOSuppT in prediction of progression to biologic agents or discharge from specialist care.

Methods

FeNOSuppT was measured at home using remote monitoring technology of inhaler use alongside daily F _ENO measurement over 7 days. Long-term clinical outcomes in terms of progression to biologic agent or discharge from specialist care were compared for non-suppressors and suppressors.

Measurements and main results

Of the 162 subjects, 135 successfully completed the test with 81 (60%) positive F _ENO suppression tests. Subjects with a negative FeNOSuppT were more likely to proceed to biologic therapy (39 of 54 patients, 72%) compared to those with a positive FeNOSuppT (35 of 81 patients, 43%, p=0.001). In subjects with a positive FeNOSuppT, predictors of progression to biologic therapy included higher dose of maintenance steroid at initial assessment and prior intensive care unit admission. These subjects had a significant rise in F _ENO between post-suppression test and follow-up (median, 33 (IQR 25-55) versus 71 (IQR 24-114); p=0.009), which was not explained by altered corticosteroid dose.

Conclusions

A negative FeNOSuppT correlates with progression to biologic therapy. A positive FeNOSuppT, with subsequent maintenance of "optimised" F _ENO, predicts a subgroup of patients in whom asthma control is preserved with adherence to high-dose ICS/long-acting β2 agonist and who can be discharged from specialist care.

Pro: Access to advanced therapies for severe asthma should be restricted to patients with satisfactory adherence to maintenance treatment

Inhaled corticosteroids (ICS) are the core component of asthma treatment and the only maintenance therapy known to prevent asthma death. There is currently no evidence that biologics prevent asthma death in people with asthma, and as such, biologics cannot be recommended as an alternative to ICS therapy. Taking the time to assess adherence and provide interventions and education to support patients in asthma self-management has been shown to improve patient outcomes. It is therefore our responsibility as healthcare professionals to ensure that patients are supported, educated and motivated to adhere to ICS therapy before progressing to biologic therapies.

ICS save lives. It is therefore our responsibility as healthcare professionals to ensure that patients are supported, educated and motivated to improve poor ICS adherence before treatment is further escalated to biologic therapy. https://bit.ly/3o2q26i

How I do it. Work-up of severe asthma

CASE EXAMPLE

A 56-year-old gentleman has difficult to control asthma and a history of four exacerbations in the prior 12 months despite high-dose inhaled corticosteroids (ICS) and additional controller therapies. Is he suitable for more advanced therapeutic options?

SCOPE OF REVIEW

We herein review the clinical assessment of a patient with suspected severe asthma, discuss factors contributing to poor asthma control and how biomarkers assist in disease investigation and stratification.

HOW I DO IT

The key components of our multidisciplinary approach are to confirm an asthma diagnosis and adherence to treatment, to assess any contributing comorbidities or confounding factors, and to stratify what type of asthma our patient has. The combination of spirometry and repeated measures of key biomarkers of type-2 airway inflammation - the blood eosinophil count and fractional exhaled nitric oxide - identifies whether poor disease control is driven by uncontrolled, ICS-resistant type-2 airway inflammation or ongoing airflow obstruction. A failure to elicit evidence of either suggests an alternative driver for the patient's symptoms including chronic airway infection and non-asthma causes. Each phenotype represents a treatable trait that requires a specific targeted approach. Critically, steroids can cause harm and their use should be guided by objective evidence of inflammation rather than symptoms alone.

CASE CONCLUSION

After assessment of treatment adherence and exclusion of relevant comorbidities, the patient was found to have severe asthma with ICS-resistant type-2 airway inflammation. We will consider additional treatment options at our next appointment (Part 2/2 of this How I Do It series).

Measuring adherence to therapy in airways disease

Non-adherence to medication is one of the most significant issues in all airways disease and can have a major impact on disease control as well as on unscheduled healthcare utilisation. It is vital that clinicians can accurately determine a patient's level of adherence in order to ensure they are gaining the maximal benefit from their therapy and also to avoid any potential for unnecessary increases in therapy. It is essential that measurements of adherence are interpreted alongside biomarkers of mechanistic pathways to identify if improvements in medication adherence can influence disease control. In this review, the most common methods of measuring adherence are discussed. These include patient self-report, prescription record checks, canister weighing, dose counting, monitoring drug levels and electronic monitoring. We describe the uses and benefits of each method as well as potential shortcomings. The practical use of adherence measures with measurable markers of disease control is also discussed.

Educational aims

To understand the various methods available to measure adherence in airways disease.To learn how to apply these adherence measures in conjunction with clinical biomarkers in routine clinical care.