Remotely Monitored Therapy and Nitric Oxide Suppression Identifies Nonadherence in Severe Asthma.

RATIONALE: Poor adherence is common in difficult-to-control asthma. Distinguishing patients with difficult-to-control asthma who respond to inhaled corticosteroids (ICS) from refractory asthma is an important clinical challenge. OBJECTIVES: Suppression of fractional exhaled nitric oxide (FeNO) with directly observed ICS therapy over 7 days can identify nonadherence to ICS treatment in difficult-to-control asthma. We examined the feasibility and utility of FeNO suppression testing in routine clinical care within UK severe asthma centers using remote monitoring technologies. METHODS: A web-based interface with integrated remote monitoring technology was developed to deliver FeNO suppression testing. We examined the utility of FeNO suppression testing to demonstrate ICS responsiveness and clinical benefit on electronically monitored treatment with standard high-dose ICS and long-acting ß2-agonist treatment. MEASUREMENTS AND MAIN RESULTS: Clinical response was assessed using the Asthma Control Questionnaire-5, spirometry, and biomarker measurements (FeNO and peripheral blood eosinophil count). Of 250 subjects, 201 completed the test with 130 positive suppression tests. Compared with a negative suppression test, a positive test identified a FeNO-low population when adherent with ICS/long-acting ß2-agonist (median, 26 ppb [interquartile range, 16-36 ppb] vs. 43 ppb [interquartile range, 38-73 ppb]) with significantly greater FEV1% (mean, 88.2 ± 16.4 vs. 74.1 ± 20.9; P < 0.01). Asthma Control Questionnaire-5 improved significantly in both groups (positive test: mean difference, -1.2; 95% confidence interval, -0.9 to -1.5; negative test: mean difference, -0.9; 95% confidence interval, -0.4 to -1.3). CONCLUSIONS: Remote FeNO suppression testing is an effective means of identifying nonadherence to ICS in subjects with difficult-to-control asthma and the substantial population of subjects who derive important clinical benefits from optimized ICS/long-acting ß2-agonist treatment.

Non-adherence in difficult asthma and advances in detection.

Non-adherence to anti-inflammatory therapies is common in patients referred for specialist assessment at difficult-to-treat asthma services. In the difficult asthma setting, non-adherence to treatment is associated with poor baseline asthma control, increased frequency of exacerbations and asthma-related hospitalizations, as well as increased risk of death. Here, we present a review of the current literature surrounding the prevalence and risks of non-adherence in difficult asthma and we report on current methods of measuring treatment adherence and advances in the detection of non-adherence. We will also explore methods by which non-adherence in difficult asthma can be addressed.

Nonadherence in difficult asthma - facts, myths, and a time to act.

Nonadherence to prescribed treatment is an important cause of difficult asthma. Rates of nonadherence amongst asthmatic patients have been shown to range between 30% and 70%. This is associated with poor health care outcomes and increased health care costs. There is no such thing as a "typical" nonadherent patient. The reasons driving nonadherence are multifactorial. Furthermore, adherence is a variable behavior and not a trait characteristic. Adherence rates can vary between the same individual across treatments for different conditions. There is no consistent link between socioeconomic status and nonadherence, and although some studies have shown that nonadherence is more common amongst females, this is not a universal finding. The commonly held perception that better adherence is driven by greater disease severity has been demonstrated to not be the case, in both pediatric and adult patients. Identification of nonadherence is the first step. If adherence is not checked, it is likely that poor adherence will be labeled as refractory disease. Failure to identify poor adherence may lead to inappropriate escalation of therapy, including the potential introduction of complex biological therapies. Surrogate measures, such as prescription counting, are not infallible. Nonadherence can be difficult to identify in clinical practice, and a systematic approach using a variety of tools is required. Nonadherence can be successfully addressed. Therefore, assessment of adherence is of paramount importance in difficult asthma management, in order to reduce exacerbations and steroid-related side effects as well as hospital and intensive care admissions, health care cost, and inappropriate treatment escalation. In this paper, we present an overview of the literature surrounding nonadherence in difficult asthma. We explore the facts and myths surrounding the factors driving nonadherence as well as how it can be identified and addressed.