Medication compliance and disease exacerbation in patients with asthma: a retrospective study of managed care data

A randomized crossover study assessing critical errors, preferences, and ease of use of two multidose powder inhalers

BACKGROUND

The effectiveness of inhaled medications in asthma and COPD is significantly impacted by inhalation errors. Feedback mechanisms, built into the design of the inhaler might reduce the number of critical errors. This study compares critical errors, preferences, and ease of use of two dry powder inhalers, the Nexthaler, and the Turbuhaler.

RESEARCH DESIGN AND METHODS

In this multi-center, prospective, randomized, open-label, cross-over study, the proportions of asthma and COPD patients making critical errors were compared between the Nexthaler and Turbuhaler after 4 weeks of clinical use, after having been trained for the correct use of both inhalers.

RESULTS

Ninety and 49 patients with asthma and COPD, respectively, were assessed. No significant difference was found in the number of critical errors between the two inhalers (3 with Nexthaler and 5 with Turbuhaler). However, more patients preferred the Nexthaler (57.6%) over the Turbuhaler (34.5%) (p = 0.006), while 7.9% stated no preference.

CONCLUSIONS

The study found no significant differences in critical error rate between the Nexthaler and Turbuhaler but the Nexthaler was preferred over the Turbuhaler. This study highlights the importance of dedicating sufficient time to instructing patients on the correct inhalation technique, which can lead to long-term retention of the inhalation technique.

Impact of treatment adherence and inhalation technique on asthma outcomes of pediatric patients: a longitudinal study

Introduction: We aimed to evaluate the longitudinal relationships, both at between- and within-person levels, that adherence to inhaled corticosteroid-based maintenance treatment and inhalation technique present with symptom control, exacerbations, and health-related quality of life (HRQoL) in children and adolescents with asthma. Methods: Participants (6-14 years old) from the ARCA (Asthma Research in Children and Adolescents) cohort-a prospective, multicenter, observational study (NCT04480242)-were followed for a period from 6 months to 5 years via computer-assisted telephone interviews and a smartphone application. The Medication Intake Survey-Asthma (MIS-A) was administered to assess the implementation stage of adherence, and the Inhalation Technique Questionnaire (InTeQ) was used to assess the five key steps when using an inhaler. Symptom control was measured with the Asthma Control Questionnaire (ACQ), and HRQL was measured with the EQ-5D and the Patient-Reported Outcomes Measurement Information System-Pediatric Asthma Impact Scale (PROMIS-PAIS). Multilevel longitudinal mixed models were constructed separately with symptom control, exacerbation occurrence, EQ-5D, and PROMIS-PAIS as the dependent variables. Results: Of the 360 participants enrolled, 303 (1,203 interviews) were included in the symptom control and exacerbation analyses, 265 (732) in the EQ-5D, and 215 (617) in the PROMIS-PAIS. Around 60% of participants were male subjects, and most of them underwent maintenance treatment with inhaled corticosteroids plus long-acting β-agonists in a fixed dose (73.3%). Within-person variability was 83.6% for asthma control, 98.6% for exacerbations, 36.4% for EQ-5D, and 49.1% for PROMIS-PAIS. At the within-person level, patients with higher adherence had better symptom control (p = 0.002) and HRQoL over time (p = 0.016). Patients with a better inhalation technique reported worse HRQoL simultaneously (p = 0.012), but they showed better HRQoL in future assessments (p = 0.012). The frequency of reliever use was associated with symptom control (p < 0.001), exacerbation occurrence (p < 0.001), and HRQoL (p = 0.042); and boys were more likely to present better symptom control and HRQoL than girls. Conclusion: Our results confirm longitudinal associations at the within-person level of the two indicators of quality use of inhalers: for adherence to maintenance treatment with symptom control and HRQoL, and for the inhalation technique with HRQoL. Although treatment adherence was shown to be excellent, a third of the participants reported a suboptimal inhalation technique, highlighting the need for actions for improving asthma management of the pediatric population.

Machine Learning Approaches to Predict Asthma Exacerbations: A Narrative Review

The implementation of artificial intelligence (AI) and machine learning (ML) techniques in healthcare has garnered significant attention in recent years, especially as a result of their potential to revolutionize personalized medicine. Despite advances in the treatment and management of asthma, a significant proportion of patients continue to suffer acute exacerbations, irrespective of disease severity and therapeutic regimen. The situation is further complicated by the constellation of factors that influence disease activity in a patient with asthma, such as medical history, biomarker phenotype, pulmonary function, level of healthcare access, treatment compliance, comorbidities, personal habits, and environmental conditions. A growing body of work has demonstrated the potential for AI and ML to accurately predict asthma exacerbations while also capturing the entirety of the patient experience. However, application in the clinical setting remains mostly unexplored, and important questions on the strengths and limitations of this technology remain. This review presents an overview of the rapidly evolving landscape of AI and ML integration into asthma management by providing a snapshot of the existing scientific evidence and proposing potential avenues for future applications.

Relationships between Key Functions of Patient-Provider Communication, Trust, and Motivation across White, African American, and Hispanic/Latino Patients with Asthma

Patient-provider communication is essential for providing effective care for asthma patients. However, little is known about key functions of communication and their relationships with outcomes in asthma patients across racial/ethnic groups. This study assessed asthma patients' perceptions of key functions of patient-provider communication, and examined associations between key functions, trust, and motivation across racial/ethnic groups. In this study, a sample of 470 US adults responded to an assessment of patient-provider communication, trust, and motivation through an electronically administered survey. Key functions of patient-provider communication included: exchanging information, responding to emotions, making decisions, enabling self-management, managing uncertainty, and fostering relationships. Results showed no differences in the mean scores of key functions of communication across racial/ethnic groups. The key function fostering relationships was positively associated with trust and motivation in both Whites and African Americans. However, the key function making decisions was associated with trust, and the key function managing uncertainty was associated with motivation only for Hispanic/Latinos. Results suggest different cultures may place different values on key functions of communication which may engender trust and motivation. Practical implications and suggestions for future research are discussed.

Association Between Clinical Burden and Blood Eosinophil Counts in Asthma: Findings From a Korean Adult Asthma Cohort

BACKGROUND

Some reports have suggested that the clinical and economic burdens of asthma are associated with blood eosinophil levels. The association between clinical burden and blood eosinophil counts were evaluated in a Korean adult asthma cohort.

METHODS

Clinical information including blood eosinophil counts that were not affected by systemic corticosteroids were extracted from the Cohort for Reality and Evolution of Adult Asthma in Korea database. Clinical burden was defined as 1) asthma control status, 2) medication demand and 3) acute exacerbation (AE) events during 1 consecutive year after enrollment. All patients were divided into atopic and non-atopic asthmatics. The associations between asthma outcomes and the blood eosinophil count were evaluated.

RESULTS

In total, 302 patients (124 atopic and 178 non-atopic asthmatics) were enrolled. In all asthmatics, the risk of severe AE was higher in patients with blood eosinophil levels < 100 cells/µL than in patients with levels ≥ 100 cells/µL (odds ratio [OR], 5.406; 95% confidence interval [CI], 1.266-23.078; adjusted P = 0.023). Among atopic asthmatics, the risk of moderate AE was higher in patients with blood eosinophil levels ≥ 300 cells/µL than in patients with levels < 300 cells/µL (OR, 3.558; 95% CI, 1.083-11.686; adjusted P = 0.036). Among non-atopic asthmatics, the risk of medication of Global Initiative for Asthma (GINA) steps 4 or 5 was higher in patients with high blood eosinophil levels than in patients with low blood eosinophil levels at cutoffs of 100, 200, 300, 400, and 500 cells/µL.

CONCLUSION

The baseline blood eosinophil count may predict the future clinical burden of asthma.

Medication Cost-Savings and Utilization of Generic Inhaled Corticosteroid (ICS) and Long-Acting Beta-Agonist (LABA) Drug Products in the USA

BACKGROUND

In the USA, drug costs associated with the inhaled corticosteroid (ICS) and long acting β agonist (LABA) combination products have been increasing since 2001. In January 2019, the first generic ICS/LABA drug product was approved by the U.S. Food and Drug Administration.

METHODS

We investigated retrospectively the effects of the first approved generic ICS/LABA drug from 2019 to 2020 on the wholesale cost-savings and prescription dispensing using the IQVIA data system in the USA.

RESULTS

The marketing of the first generic for fluticasone propionate and salmeterol xinafoate dry powder inhaler was associated with $941 million in drug cost-savings during the first year for this class of medications. Although the brand-name drug manufacturer concurrently introduced its authorized generic, these cost-savings were driven by the averaged unit cost of the approved generic at $115, compared to $169 for the authorized generic and $334 for the branded product. Generic initiation and substitution with the first generic were, respectively, higher compared to those with authorized generics; however, overall dispensing of the first generic was lower than that of its branded product. As in the case of budesonide and formoterol fumarate dry powder inhaler, marketing of authorized generics alone was not associated with any noticeable change in sales or prescription cost-saving.

CONCLUSION

We estimated that more than 20% of prescription cost-saving was achieved for the ICS/LABA dry powder inhalers in the first year following the introduction of the first approved generic, even though generic utilization remained lower than that of the branded counterpart.

Measuring Medication Adherence in a Population-Based Asthma Administrative Pharmacy Database: A Systematic Review and Meta-Analysis

Background

Limited studies have systematically reviewed the literature to identify and compare the various database methods and optimal thresholds for measuring medication adherence specific to adolescents and adults with asthma. In the present study, we aim to identify the methods and optimal thresholds for measuring medication adherence in population-based pharmacy databases.

Methods

We searched PubMed, Embase, International Pharmaceutical Abstracts (IPA), Web of Science, Google Scholar, and grey literature from January 1, 1998, to March 16, 2021. Two independent reviewers screened the studies, extracted the data, and assessed the quality of the studies. A quantitative knowledge synthesis was employed.

Results

Thirty-eight (38) retrospective cohort studies were eligible. This review identified 20 methods for measuring medication adherence in adolescent and adult asthma administrative health records. Two measures namely the medication possession ratio (MPR) and proportion of days covered (PDC) were commonly reported in 87% of the literature included in this study. From the meta-analysis, asthma patients who achieved adherence threshold of "0.75-1.00" [OR: 0.56, 95% CI: 0.41 to 0.77] and ">0.5" [OR: 0.71, 95% CI: 0.54 to 0.94] were less likely to experience asthma exacerbation.

Conclusion

Despite their limitations, the PDC and the MPR still remain the most common measures for assessing adherence in asthma pharmacy claim databases. The evidence synthesis showed that an adherence threshold of at least 0.75 is optimal for classifying adherent and non-adherent asthma patients.

Health Workers' Practices in Assessment and Management of Children with Respiratory Symptoms in Primary Care Facilities in Uganda: A FRESH AIR Descriptive Study

INTRODUCTION

Globally, acute lower respiratory infections are the leading cause of mortality among children under 5 years. Following World Health Organization primary care guidelines, pneumonia is diagnosed based on cough/difficult breathing and fast breathing. We aimed to describe the practices of healthcare workers in primary care health facilities in Uganda in the management of young children with respiratory symptoms especially regarding asthma as opposed to pneumonia.

METHODS

Health workers were observed during clinical consultations with children 1-59 months of age presenting with cough and/or difficult breathing at recruitment. Afterward, an exit interview with the caregiver was conducted. Health center availability of clinical guidelines, equipment and supplies for management of children with respiratory symptoms was assessed systematically.

RESULTS

A total of 218 consultations with 50 health workers at six health centers were included. Median consultation time was 4 min. Health workers asked history relevant to distinguishing asthma from pneumonia in 16% of consultations. The respiratory rate was counted in 10%. Antibiotics were prescribed to 32% of all the children and to 39% of children diagnosed with pneumonia. Caregivers reported being informed of findings and possible diagnosis in 5% of cases. Medicine and equipment needed for diagnosing and treating asthma were generally unavailable.

CONCLUSION

Clinical practices among Ugandan health workers in primary care are insufficient to distinguish between main causes of respiratory symptoms, especially asthma as opposed to pneumonia, in children under five. Irrational use of antibiotics is widespread. Clear communication with caregivers is lacking. This could be due to lack of relevant competencies, medicines, time and supplies.

LAY SUMMARY

Globally, the most frequent cause of death for children under five is infections in the lower airways. The World Health Organization recommends that in local health clinics this is defined as cough/difficult breathing and fast breathing. This article focuses on the practices of local health workers in Uganda and how they in practice diagnose and treat children under five with these symptoms. In addition, we try to estimate how much the caregivers of the children understand from the consultation. This is done by observing the healthcare workers (HCWs) and by interviewing the caregivers. In general, we found that the consultations were too short, that too few of the health workers looked for important signs for lower airways disease such as fast breathing and that antibiotics were prescribed in too many of the consultations. Also, the length and quality of the consultations and the supplies at the local health clinics were not sufficient to diagnose and treat asthma, which can often be mistaken for an infection. We believe that it is an important problem that too few children with asthma are being diagnosed correctly and that antibiotics are being prescribed too frequently, the latter being an important cause of antibiotic resistance. Relevant action must be taken to improve this.

The association between control level and self-reported treatment adherence across different treatment types in Japanese asthma patients

BACKGROUND

Poor control of asthma symptoms is associated with a higher asthma disease burden, and asthma medication adherence is a known predictor for a better control status. This study sought to describe the current asthma control status, self-reported treatment adherence, and the association between them, as well as to describe how control level and better adherence impact the health outcomes of asthma patients.

METHODS

This study used cross-sectional data from the 2018 Japan National Health and Wellness Survey (NHWS). Asthma control status and adherence were assessed using the Asthma Control Test (ACT) and Morisky Medication Adherence Scale-8 (MMAS-8), respectively. Asthma treatment and patients' health outcomes, i.e. health-related quality of life (HRQoL) and work productivity, were self-reported. Asthma control and self-reported treatment adherence were analyzed descriptively, and the association was investigated by comparing mean ACT scores across adherence levels. Health outcomes were compared across control and adherence levels by multivariate analyses.

RESULTS

A total of 816 patients had a physician diagnosis of asthma, with 67.0% reporting at least well controlled (ALWC). Of 505 asthma patients receiving prescription medication, half reported low adherence to medication use. Among asthma patients reporting high adherence, 35.6% were not well controlled (NWC). After adjusting for covariates, NWC asthma patients had significantly worse health outcomes than ALWC patients.

CONCLUSIONS

One-third of asthma patients in Japan suffer from poorly controlled asthma. Results of the 2018 NHWS show that poor control status negatively affects patients' HRQoL and work productivity, suggesting an unmet need for better treatments to lessen the burden of asthma.

Automatic Audio-Based Classification of Patient Inhaler Use: A Pharmacy Based Study

Chronic respiratory diseases may be controlled through the delivery of medication to the airways and lungs using an inhaler. However, adherence to correct inhaler technique is poor, which impedes patients from receiving maximum clinical benefit from their medication. In this study, the Inhaler Compliance Assessment device was employed to record audio of patients using a Diskus dry powder inhaler. An algorithm that classifies inhaler sounds (blister, inhalation, interference) was developed to automatically assess patient adherence from these inhaler audio recordings. The presented algorithm employed audio-based signal processing methods and statistical modeling in the form of quadratic discriminant analysis (QDA). A total of 350 audio recordings were obtained from 70 patients. The acquired audio dataset was split evenly for training and testing. A total accuracy of 85.35% was obtained (testing dataset) for this 3-class classification system. A sensitivity of 89.22% and 70% was obtained for inhalation and blister detection respectively. This approach may have significant clinical impact by providing healthcare professionals with an efficient, objective method of monitoring patient adherence to inhaler treatment.

Association between adherence and severe asthma exacerbation: A systematic review and meta-analysis

OBJECTIVE

To assess the association between adherence levels and severe asthma exacerbation.

DESIGN

A systematic search was performed from inception to November 2018 on the following databases: PubMed, CENTRAL, EMBASE, and ClinicalTrials.gov.

SETTING AND PARTICIPANTS

Randomized-controlled trials (RCTs) and cohort and case-control studies that investigated the impact of adherence to controller medications on severe asthma exacerbation were included in the analysis. Data extraction was undertaken by 2 reviewers, and all studies were assessed for their qualities using the Cochrane risk of bias tool for RCT and the Newcastle-Ottawa scale for cohort and case-control studies. Random-effects model meta-analyses were performed.

OUTCOME MEASURES

Severe asthma exacerbation.

RESULTS

From 8061 articles, 8 studies were included in quantitative synthesis. The meta-analyses revealed that the odds of exacerbation among the patients with 80% or more adherence were lowered by 47% (odds ratio 0.53 [95% CI 0.42-0.66], P < 0.001) compared with less than 80%. When compared with less than 20% adherence, a 33% reduction in the odds (0.67 [0.53-0.86], P = 0.001) was associated with the patients achieving 50% or more, whereas a decrease in exacerbation was not associated with 20% to 49% adherence (0.94 [0.85-1.04], P = 0.22). In addition, a 2.4-fold increase in the odds (2.4 [2.1-2.7], P < 0.001) was associated with discontinuation of therapy.

CONCLUSION

The highest reduction in the odds of exacerbation was associated with patients achieving 80% or more adherence, and the odds also reduced among those with 50% or more adherence, whereas a substantial increase in exacerbation was associated with discontinuation of therapy.

Does a tailored intervention to promote adherence in patients with chronic lung disease affect exacerbations? A randomized controlled trial

BACKGROUND

Poor medication-adherence is common in chronic lung patients, resulting in reduced health-outcomes and increased healthcare-costs. This study aimed to investigate the impact of an acoustic reminder and support calls on adherence to inhaled therapy in asthma and COPD patients and to determine their effect on exacerbations.

METHODS

This single-blinded randomized controlled trial investigated asthma and COPD patients during 6 months in an ambulatory setting. The intervention consisted of daily alarm clock and support phone calls, whenever use of rescue medication doubled or inhaled medication was not taken as prescribed. Primary outcome was time to next exacerbation. Frequency of exacerbations, adherence to inhaled medication and quality of life scores were secondary outcomes. Cox and Poisson regression were used to determine intervention effect on time to exacerbation and frequency of exacerbations, respectively.

RESULTS

Seventy-five participants were assigned to the intervention group and 74 to usual follow-up care. During a median follow-up of 6.2 months, 22 and 28% in the intervention and control groups respectively, experienced at least one exacerbation. Intervention had no effect on time to first exacerbation (HR 0.65, 95% CI 0.21 to 2.07, P = .24), but showed a trend toward a 39% decreased frequency of exacerbations (RR = 0.61, 95% CI 0.35 to 1.03, P = .070) for the adjusted models, respectively. The intervention group had significantly more days with 80-100% taking adherence regarding puff inhalers (82 ± 14% vs. 60 ± 30%, P < .001) and dry powder capsules (90 ± .10% vs. 80 ± 21%, P = .01). Timing adherence in participants using puff inhalers was higher in the intervention group (69 ± 25% vs. 51 ± 33%, P < .001). No significant differences in QoL were found between the two groups.

CONCLUSION

Participants assigned to the intervention group had significantly better taking and timing adherence of inhaled medication resulting in a trend towards a decreased frequency of exacerbations. However, no effect on time to next exacerbation was observed.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02386722, Registered 14 February 2014.

Medication adherence in patients with asthma using once-daily versus twice-daily ICS/LABAs

OBJECTIVE

This real-world observational study compared medication adherence and persistence among patients with asthma receiving the once-daily inhaled corticosteroid/long-acting β₂-agonist (ICS/LABA) fluticasone furoate/vilanterol (FF/VI) versus the twice-daily ICS/LABAs budesonide/formoterol (B/F) and fluticasone propionate/salmeterol (FP/SAL).

METHODS

This retrospective cohort study conducted using IQVIA^TM Health Plan Claims Data included patients with asthma ≥18 years of age initiating ICS/LABA therapy with FF/VI, B/F, or FP/SAL between January 1, 2014 and June 30, 2016 (index date). Patients had ≥12 months and ≥3 months of continuous eligibility pre- and post-index date, respectively. Patients receiving FF/VI were separately matched 1:1 with patients receiving B/F or FP/SAL using propensity score matching (PSM) and multivariable regression to balance baseline covariates between cohorts. The primary endpoint was medication adherence, measured by proportion of days covered (PDC). Secondary endpoints included proportion of patients achieving PDC ≥ 0.5 and PDC ≥ 0.8 and persistence with index medication, measured by time to discontinuation (>45-day gap in therapy).

RESULTS

After PSM, 3,764 and 3,339 patients receiving FF/VI were matched with patients receiving B/F or FP/SAL, respectively. Mean PDC was significantly higher for FF/VI versus B/F (0.453 vs 0.345; adjusted p < 0.001) and FP/SAL (0.446 vs 0.341; adjusted p < 0.001). The proportion of patients achieving PDC ≥ 0.5 or PDC ≥ 0.8, and treatment persistence were significantly higher for FF/VI versus B/F and FP/SAL (all p < 0.001).

CONCLUSIONS

In this real-world study, patients initiating FF/VI had better adherence and lower risk of discontinuing treatment versus B/F or FP/SAL, suggesting that once-daily ICS/LABA treatment might improve adherence and persistence compared with twice-daily alternatives.

Incorporating adherence in cost-effectiveness analyses of asthma: a systematic review

Aims: Non-adherence is associated with poor clinical outcomes among patients with asthma. While cost-effectiveness analysis (CEA) is increasingly used to inform value assessment of the interventions, most do not take into account adherence in the analyses. This study aims to: (1) Understand the extent of studies considering adherence as part of the economic analyses, and (2) summarize the methods of incorporating adherence in the economic models. Materials and methods: A literature search was performed from the inception to February 2018 using four databases: PubMed, EMBASE, NHS EED, and the Tufts CEA registry. Decision model-based CEA of asthma were identified. Outcomes of interest were the number of studies incorporating adherence in the economic models, and the incorporating methods. All data were extracted using a standardized data collection form. Results: From 1,587 articles, 23 studies were decision model-based CEA of asthma, of which four CEA (17.4%) incorporated adherence in the analyses. Only the method of incorporating adherence by adjusting treatment effectiveness according to adherence levels was demonstrated in this review. Two approaches were used to derive the associations between adherence and effectiveness. The first approach was to apply a mathematical formula, developed by an expert panel, and the second was to extrapolate the associations from previous published studies. The adherence-adjusted effectiveness was then incorporated in the economic models. Conclusions: A very low number of CEA of asthma incorporated adherence in the analyses. All the CEA adjusted treatment effectiveness according to adherence levels, applied to the economic models.

Examination of Barriers to Medication Adherence, Asthma Management, and Control Among Community Pharmacy Patients With Asthma

OBJECTIVE

To describe the prevalence of common barriers to asthma medication adherence and examine associations between patient-reported asthma controller adherence and asthma control, therapy adherence barriers, and asthma management characteristics.

METHODS

Previously developed asthma-specific tool was pilot tested on a convenience sample of adult patients with persistent asthma. The following data were collected via patient survey: demographic characteristics and comorbidities, adherence, asthma control, and asthma management characteristics. Descriptive and inferential statistics were used to address the study objective.

RESULTS

The patients (N = 93) were 45.4 (17.2) years of age, and 66.7% were female. The majority had poor (68.8%) adherence, with 61.3% of patients having controlled asthma. There was no significant association between adherence and asthma control. The mean number of barriers for good and poor adherence groups differed significantly: 2.0 ± 1.1 and 5.4 ± 2.4, respectively (P < .0001). Having an asthma action plan (AAP) was the only asthma management characteristic significantly related to adherence. The majority of patients with poor adherence did not have an AAP (76.6%), whereas 81.5% of patients with good adherence did have an AAP (P < 0.0001).

CONCLUSIONS

The use of this survey tool confirmed presence of asthma-specific barriers, thus using this specialized approach may lead to more effective, targeted counseling in community pharmacy settings.

Influence of Adherence to Inhaled Corticosteroids and Inhaler Handling Errors on Asthma Control in a Japanese Population

Objective High adherence to medications and accurate handling of inhaler devices are important for asthma management. However, few reports to date have simultaneously evaluated adherence and handling errors. We therefore investigated the adherence to inhaled corticosteroid (ICS) and inhaler handling errors in the same patients in cooperation with pharmacists. Methods Data were derived from a survey of physicians and pharmacists treating asthma patients who visited participating hospitals and pharmacies from July 2012 to January 2013. The patients were evaluated for asthma control using the Asthma Control Test (ACT) and for inhaler handling errors using checklists. ICS adherence was evaluated based on pharmaceutical records. Results Adherence among participants (n=290) was 33.3% (mean), and the percentage of inhaler handling errors was 20.0% (mean). Total inhalation times in the high-adherence group were fewer than those in the low-adherence group. In a comparison by device, adherence to pressurized metered dose inhalers was significantly lower than that to Diskus® inhalers, presumably attributable to the total number of inhalations per day. Adherence, handling errors, and total number of inhalations per day were significantly different between the asthma-controlled group and the uncontrolled group. A multivariate analysis showed that adherence and handling errors were independent factors contributing to asthma control. Conclusion Our data indicated that both adherence to ICS and device handling errors contributed to asthma control in this population.

Regular follow-up visits reduce the risk for asthma exacerbation requiring admission in Korean adults with asthma

BACKGROUND

Asthma requires regular follow-up visits and sustained medication use. Although several studies have reported the importance of adherence to medication and compliance with the treatment, none to date have reported the importance of regular follow-up visits. We investigated the effects of regular clinical visits on asthma exacerbation.

METHODS

We used claims data in the national medical insurance review system provided by the Health Insurance Review and Assessment Service of Korea. We included subjects aged ≥ 15 years with a diagnosis of asthma, and who were prescribed asthma-related medication, from July 2013 to June 2014. Regular visitors (frequent visitors) were defined as subjects who visited the hospital for follow-up of asthma three or more times per year.

RESULTS

Among 729,343 subjects, 496,560 (68.1%) were classified as regular visitors. Old age, male sex, lack of medical aid insurance, attendance of a tertiary hospital, a high Charlson comorbidity index, and a history of admission for exacerbated asthma in the previous year were significant determining factors for regular visitor status. When we adjusted for all these factors, frequent visitors showed a lower risk of asthma exacerbation requiring general ward admission (odds ratio [OR] 0.48; 95% confidence interval [CI] 0.47-0.50; P < 0.001), emergency room admission (OR 0.83; 95% CI 0.79-0.86; P < 0.001), and intensive care unit admission (OR 0.49; 95% CI 0.44-0.54; P < 0.001) than infrequent visitors.

CONCLUSIONS

Regular clinical visits are significantly associated with a reduced risk of asthma exacerbation requiring hospital admission in Korean adults with asthma.

Risk factors of asthma exacerbation based on asthma severity: a nationwide population-based observational study in South Korea

OBJECTIVES

Asthma exacerbation, associated with many risks factors, can reflect management failure. However, little is known about how risk factors are associated with exacerbation, according to asthma severity. We aimed to investigate differences in risk factors in patients with different asthma severity and evaluate whether risk factors differed between frequent exacerbators and patients with single exacerbation.

DESIGN

Nationwide population-based observational study.

SETTING

Korean National Sample Cohort database.

PARTICIPANTS

We included 22 130 adults with asthma diagnoses more than twice (ICD-10 (International Classification of Diseases, Tenth revision) codes J45 and J46) and one prescription for asthma medication from 2010 to 2011.

OUTCOME MEASURES

Asthma exacerbation was defined as having a corticosteroid (CS) burst characterised by a prescription of high-dose oral CS for ≥3 days or one systemic CS injection, hospitalisation or emergency department visit.

RESULTS

Among severities, history of CS bursts was significantly associated with exacerbation. In mild and moderate asthma, exacerbation was significantly associated with age ≥45 years, being female, gastro-oesophageal reflux disease and chronic rhinitis. High medication possession ratio (MPR≥50%), compared with low MPR (<20%) showed adjusted ORs of 0.828 (95% CI 0.707 to 0.971) and 0.362 (0.185 to 0.708) in moderate and severe asthma, respectively. In severe asthma, compared with mild asthma, only allergic rhinitis and history of hospitalisation were strongly associated with exacerbation. When comparing frequent exacerbators to patients with single exacerbation, age ≥45 years, atopic dermatitis, anxiety and history of CS burst were significant risk factors in mild and moderate asthma, whereas no risk factors were significant in severe asthma.

CONCLUSIONS

Different associations between risk factors and asthma exacerbations based on asthma severity suggest that patients with mild asthma require greater attention to their age and comorbidities, whereas those with severe asthma require greater attention to hospitalisation history and drug adherence.

Increased Risk of Exacerbation in Asthma Predominant Asthma-Chronic Obstructive Pulmonary Disease Overlap Syndrome

Background

Obstructive airway disease patients with increased variability of airflow and incompletely reversible airflow obstruction are often categorized as having asthma–chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS). ACOS is heterogeneous with two sub-phenotypes: asthma-ACOS and COPD-ACOS. The objective of this study was to determine the difference in risk of exacerbation between the two sub-phenotypes of ACOS.

Methods

A total of 223 patients exhibiting incompletely reversible airflow obstruction with increased variability (spirometrically defined ACOS) were enrolled. These patients were divided into asthma-ACOS and COPD-ACOS according to their physician's diagnosis and smoking history of 10 pack-years. Within-group comparisons were made for asthma-ACOS versus COPD-ACOS and light smokers versus heavy smokers.

Results

Compared to patients with COPD-ACOS, patients with asthma-ACOS experienced exacerbation more often despite their younger age, history of light smoking, and better lung function. While the light-smoking group showed better lung function, they made unscheduled outpatient clinic visits more frequently. On multivariate analysis, asthma-ACOS and poor inhaler compliance were significantly associated with more than two unscheduled clinic visits during the previous year.

Conclusion

Spirometrically defined ACOS includes heterogeneous subgroups with different clinical features. Phenotyping of ACOS by physician's diagnosis could be significant in predicting future risk of exacerbation.

Long-Term Inhaled Corticosteroid Adherence in Asthma Patients with Short-Term Adherence

BACKGROUND

Although the use of inhaled corticosteroids (ICS) in asthma is known to be overall erratic, the long-term use of ICS by patients selected during an episode of regular use is poorly documented.

OBJECTIVE

In a cohort of patients with asthma regularly acquiring ICS therapy over several months, we verified whether these patients remained treated in the following 12 months. The correlates of regular ICS use over this period were investigated.

METHODS

A historical cohort of patients with asthma was identified from the Echantillon généraliste de bénéficiaires national French health care reimbursement data (2007-2012). Patients (6-40 years) were selected during a regular ICS use episode, with 3 or more ICS refills within 120 days. Continuous multiple-interval measures of medication availability (CMA) were computed for the 12 months after the third dispensation, and the factors associated with a CMA value of 80% or more (adherent patients) were identified.

RESULTS

Among 5096 patients (42.1% children/teenagers, 48.8% females), only 24.0% had a CMA value of 80% or more (mean CMA = 54.4%) over the 12 months following the ICS selection period. Achieving a CMA value of 80% or more was primarily associated with being a child/teenager (P = .002), having more severe or less controlled asthma (P = .007), more previous dispensing of short-acting beta agonists (P < .0001), and receiving devices with 200 unit doses (P < .0001). Adherent patients had more frequent general practitioner visits (P < .0001), more distinct prescribers of respiratory therapy (P = .0002), and more frequent switches of ICS (P < .0001).

CONCLUSIONS

Most patients with asthma selected during an episode of regular ICS use did not maintain therapy over the following months. Adherence should be repeatedly monitored, and the reasons for discontinuation should be investigated, at prescriber and patient levels.

Understanding clinicians' attitudes toward a mobile health strategy to childhood asthma management: A qualitative study

OBJECTIVES

Mobile technology for childhood asthma can provide real-time data to enhance care. What real-time adherence information clinicians want, how they may use it, and if the data meet their clinical needs have not been fully explored. Our goal was to determine whether pediatric primary care and pulmonary clinicians believe if a sensor-based mobile intervention is useful in caring for patients with asthma.

METHODS

We recruited participants from 3 urban, primary care and 1 pulmonary practice from July to September 2015 in Hartford, CT. Forty-one participated in four focus groups, which included a demonstration of the technology. Participants were probed with open-ended questions on the type, frequency, and format of inter-visit patient information they found useful.

RESULTS

41 participants (mean age 49 (±13.7) years) were board-certified clinicians (41% MDs and 20% mid-level practitioners), practiced medicine on an average of 19 (±14) years, were primarily white (59%) and women (78%). Clinicians wanted 1) adherence to prescribed inhaler therapy and 2) data on inhaler technique. Clinicians wanted it at the time of a scheduled clinic visit but also wanted inter-visit alerts for excessive use of rescue therapy. Pulmonologists liked the mobile spirometer's provision of inter-visit lung function data; pediatricians did not share this view. Concerns with data accuracy were raised due to families who shared inhalers, access to smartphones, and protection of health information.

CONCLUSIONS

Overall, clinicians view an asthma mobile health technology as enhancing the patient-centered medical home. Pediatric primary care clinicians and pulmonologists want different information from a mobile app.

Association of emergency department albuterol dispensing with pediatric asthma revisits and readmissions

INTRODUCTION

Although pediatric asthma continues to be a highly studied disease, data to suggest clear strategies to decrease asthma related revisits or readmissions is lacking. The purpose of our study was to assess the effect of emergency department (ED) direct dispensing of beta-agonist metered dose inhalers on pediatric asthma ED revisit and readmission rates.

METHODS

We conducted a retrospective cohort study of pediatric patients discharged from the pediatric ED with a diagnosis of asthma. Our primary outcome measured the rate of asthma revisits to the ED or admissions to the hospital within 28 days. Logistic regression analysis was used to assess ED beta-agonist MDI dispensing and revisit and/or readmission as the outcome.

RESULTS

A total of 853 patients met eligibility for inclusion in the study, with 657 enrolled in the Baseline group and 196 enrolled in the ED-MDI group. The Baseline group experienced a revisit and readmission rate of 7.0% (46/657) versus 2.6% (5/196) in the ED-MDI group, (p = 0.026). ED direct dispensing of MDIs was found to be independently associated with a decreased risk of revisit or readmission (odds ratio 0.37; 95% confidence interval 0.14-0.95).

CONCLUSIONS

In our study, ED direct dispensing of beta-agonist MDIs resulted in a reduction in 28-day revisit and readmission to the hospital. Further studies should be performed to evaluate the economic impact of reducing these revisits and readmissions against the costs of maintaining a dispensing program. Our findings may support modification of asthma programs to include dispensing MDIs from the emergency department.

Asthma Controller Medication Adherence, Risk of Exacerbation, and Use of Rescue Agents Among Texas Medicaid Patients with Persistent Asthma

BACKGROUND

Adherence to asthma long-term controller medications is one of the key drivers to improve asthma management among patients with persistent asthma. While suboptimal use of controller medications has been found to be associated with more frequent use of oral corticosteroids (OCS), few studies exist regarding the relationship between adherence to controller therapy and the use of short-acting beta2-agonists (SABAs). A better understanding of the association between adherence to asthma controller agents and use of reliever medications will help health care providers and decision makers enhance asthma management.

OBJECTIVE

To determine if there is a relationship between asthma controller adherence, risk of exacerbation requiring OCS, and use of asthma rescue agents.

METHODS

Texas Medicaid claims data from January 1, 2008, to August 31, 2011, were retrospectively analyzed. Continuously enrolled patients aged 5-63 years with a primary diagnosis of asthma (ICD-9-CM code 493) and with 4 or more prescription claims for any asthma medication in 1 year (persistent asthma) were included. The index date was the date of the first asthma controller prescription, and patients were followed for 1 year. The primary outcome variables were SABA (dichotomous: less than  6 vs. ≥ 6) and OCS (continuous) use. The primary independent variable was adherence (proportion of days covered [PDC]) to asthma long-term controller medications. Covariates included demographics and nonstudy medication utilization. Multivariate logistic and linear regression analyses were employed to address the study objective.

RESULTS

The study sample (n = 32,172) was aged 15.0 ± 14.5 years, and adherence to controller therapy was 32.2% ± 19.7%. The mean number of SABA claims was 3.7 ± 3.1, with most patients having 1-5 claims (73.2%), whereas 19.4% had ≥ 6 SABA claims. The mean number of OCS claims was 1.0 ± 1.4. Adherent (PDC ≥ 50%) patients were 96.7% (OR = 1.967; 95% CI = 1.826-2.120) more likely to have ≥ 6 SABA claims when compared with nonadherent (PDC  less than  50%) patients (P  less than  0.001). As for OCS use, adherent patients had 0.11 fewer claims compared with nonadherent patients (P  less than  0.001). Importantly, patients with ≥ 6 SABA claims had 0.7 more OCS claims compared with patients with less than  6 claims for SABA (P  less than  0.001). The odds of having ≥ 6 SABA claims were higher for concurrent dual therapy users, older age, males, African Americans and higher number of nonstudy medications (P  less than  0.001). Dual therapy users, younger age, Hispanic ethnicity, and higher number of nonstudy medications were associated with an increase in OCS use (P  less than  0.005).

CONCLUSIONS

Adherence to long-term controller medications was suboptimal among patients with asthma. Adherent patients had fewer OCS claims, indicating that adherence to controller therapy is critical in preventing asthma exacerbations requiring OCS use. Although there was a positive relationship between adherence to long-term controller medication and SABA use, increased SABA use served as a predictor of increased OCS use, which indicates poor asthma control. Health care providers should be aware of OCS and SABA use among patients who are both adherent and nonadherent to asthma controller medications.

Use of ICS/LABA on Asthma Exacerbation Risk in Patients Within a Medical Group

BACKGROUND

Asthma medication ratio (AMR) ≥ 0.5 has been shown to predict asthma exacerbations. This study explores the impact of increasing or decreasing inhaled corticosteroid/long-acting beta-agonist (ICS/LABA) use over a 7-year period on achieving an AMR of ≥ 0.5.

OBJECTIVES

To (a) assess the impact of increasing use of ICS/LABAs on changes in a modified AMR (mAMR) and (b) examine asthma risk over time as measured by an mAMR over a 7-year period, adjusting for differences in baseline characteristics.

METHODS

This is a retrospective, observational study using pharmacy and medical claims from a medical group from January 1, 2003, to December 31, 2010. All patients with ≥ 1 asthma diagnosis (ICD-9-CM, 493.xx) with ≥ 1 inhaled asthma medication dispensed in each year of eligibility were included. The mAMR = total ICS controllers dispensed/(total ICS controllers dispensed + albuterol dispensed). The proportion of ICS/LABA use was determined as the number of ICS/LABA canisters dispensed/(total of ICS/LABA + ICS dispensed). Generalized linear mixed models were used to assess the effect of incremental change in ICS/LABA use on mAMR over 7 years, adjusting for differences in resource utilization, time, and asthma medication use. 

RESULTS

Nine hundred ninety patients (mean age [± SD] 34.7 years [± 18.2], 61.7% female) met all criteria. Overall, mean mAMR increased over time, while mean albuterol use decreased over time. Adjusting for covariates, we found that a 10% increase in ICS/LABA use was associated with a 9% increase (adjusted OR = 1.09, 95% CI = 1.06-1.12) in the likelihood of achieving an mAMR ≥ 0.5, while a 50% increase in ICS/LABA use was associated with a 53% increase (OR = 1.53, 95% CI = 1.31-1.80) in the likelihood of achieving an mAMR ≥ 0.5.

CONCLUSIONS

Increase in ICS/LABA use over time in a population of asthma patients was significantly associated with a higher likelihood of achieving an mAMR ≥ 0.5.

Individual and county level predictors of asthma related emergency department visits among children on Medicaid: A multilevel approach

OBJECTIVE

Disparities in asthma outcomes are well documented in the United States. Interventions to promote equity in asthma outcomes could target factors at the individual and community levels. The objective of this analysis was to understand the effect of individual (race, gender, age, and preventive inhaler use) and county-level factors (demographic, socioeconomic, health care, air-quality) on asthma emergency department (ED) visits among Medicaid-enrolled children. This was a retrospective cohort study of Medicaid-enrolled children with asthma in 29 states in 2009. Multilevel regression models of asthma ED visits were constructed utilizing individual-level variables (race, gender, age, and preventive inhaler use) from the Medicaid enrollment file and county-level variables reflecting population and health system characteristics from the Area Resource File (ARF). County-level measures of air quality were obtained from Environmental Protection Agency (EPA) data.

RESULTS

The primary modifiable risk factor at the individual level was found to be the ratio of long-term controller medications to total asthma medications. County-level factors accounted for roughly 6% of the variance in the asthma ED visit risk. Increasing county-level racial segregation (OR=1.04, 95% CI=1.01-1.08) was associated with increasing risk of asthma ED visits. Greater supply of pulmonary physicians at the county level (OR=0.81, 95% CI=0.68-0.97) was associated with a reduction in risk of asthma ED visits.

CONCLUSIONS

At the patient care level, proper use of controller medications is the factor most amenable to intervention. There is also a societal imperative to address negative social determinants, such as residential segregation.

Retrospective cohort analysis of healthcare claims in the United States characterising asthma exacerbations in paediatric patients

Background

Asthma is the most common chronic disease in childhood and places a significant burden on public and private health systems. This retrospective cohort analysis utilised administrative healthcare claims data (US Clinformatics™ Multiplan database; compliant with the US Department of Health & Human Services Health Insurance Portability and Accountability Act) to characterise asthma exacerbations requiring intervention in a US paediatric patient population.

Methods

Patients aged > 1–17 years with a recorded asthma diagnosis and receiving treatment were identified in the US Clinformatics™ Multiplan database over a 9-year period (2004–2012). Both incident and prevalent cases of asthma were included, with the most recently recorded asthma diagnosis designated as the index date. The 12-month period following the index date was analysed for asthma exacerbations, defined as an event requiring treatment with systemic corticosteroid or resulting in an asthma-related hospitalisation or emergency department visit.

Results

Data from 734,114 children with asthma (41.5 % females, 58.5 % males) were analysed, of this cohort 34.4 % experienced ≥ 1 exacerbation during the follow-up period. The proportion who experienced ≥ 1 exacerbation increased from 28.9 % in 2004 to 36.3 % in 2012, based on the reported index date. Their mean annual exacerbation frequency was 1.4; 85.8 % of exacerbations were defined by systemic corticosteroids use. A consistent trend of increased exacerbation incidence in the fall and early winter was observed, in particular exacerbations defined by systemic corticosteroid use. A greater proportion of asthma-related hospitalisations were associated with younger age.

Conclusions

Approximately one-third of children experienced ≥ 1 exacerbation in real-world clinical practice. A targeted treatment approach with a focus on those with a history of recurrent exacerbations is recommended to improve asthma control. This targeted approach could also minimise the frequent systemic corticosteroid exposure particularly at an early age when side effects of systemic corticosteroids are more pronounced.

Mismatching Among Guidelines, Providers, and Parents on Controller Medication Use in Children with Asthma

BACKGROUND

Underuse of controller medicines among children with asthma remains widespread despite national guidelines.

OBJECTIVES

To (1) assess provider prescribing patterns for asthma controller medications; (2) assess how frequently parents' reports of their child's asthma controller medicine use were mismatched with their provider's recommendations; and (3) evaluate parent attitudes and demographic characteristics associated with these mismatches.

METHODS

In this cross-sectional study, we conducted linked surveys of parents and providers of children with probable persistent asthma in a Medicaid program and 4 commercial health plans in 2011. Probable persistent asthma was defined as a diagnosis of asthma and 1 or more controller medication dispensing.

RESULTS

This study included 740 children (mean age, 8.6 years). Providers for 50% of the children reported prescribing controller medications for daily year-round use, 41% for daily use during active asthma months, and 9% for intermittent use for relief. Among parents, 72% knew which class of controller medication the provider prescribed and 49% knew the administration frequency and the medication class. Parents were less likely to report the same controller medication type as the provider, irrespective of dose and frequency, if they were Latino (odds ratio [OR], 0.23; CI, 0.057-0.90), had a household smoker (OR, 2.87; CI, 0.42-19.6), or believed the controller medicine was not helping (OR, 0.15; CI, 0.048-0.45).

CONCLUSIONS

Mismatches between parent reports and providers intentions regarding how the child was supposed to use inhaled steroids occurred for half of the children. Efforts should focus on ways to reduce mismatches between parent and provider intentions regarding controller medication use.

Evaluation of factors affecting adherence to asthma controller therapy in chest clinics in a sub-Saharan African setting: a cross-sectional study

BACKGROUND

Adherence to controller therapy in asthma is a major concern during the management of the disease.

OBJECTIVE

To determine the adherence rate and identify the predictors of low adherence to asthma controller therapy.

METHODS

A cross-sectional study including asthma patients was conducted from November 1, 2012 to May 31, 2013 in 4 chest clinics in Cameroon. The adherence to asthma treatment was rated using Morisky Medication Adherence Scale. A multivariate logistic regression analysis was performed for the identification of factors associated with adherence to asthma treatment.

RESULTS

Among the 201 asthma patients included, 133 (66.2%) were female. The mean age of participants was 41.2 years. Sixty-one (30.3%) of the patients did not visit the chest physician during the last year prior to the study. Asthma was well controlled in 118 patients (58.7%). The prevalence of low adherence rate to asthma controller therapy was 44.8% and the absence of any chest specialist visit within the last 12 months was the only factor associated with the low adherence rate to asthma treatment (OR 5.57 ; 95% CI 2.84-10.93).

CONCLUSION

The adherence rate to asthma controller therapy in Cameroon is low and it could be improved if scheduled visits are respected by patients.

Identification of factors involved in medication compliance: incorrect inhaler technique of asthma treatment leads to poor compliance

OBJECTIVE

To identify the impact of delivery device of inhaled corticosteroids and long-acting β2-agonist (ICS/LABA) on asthma medication compliance, and investigate other factors associated with compliance.

MATERIALS AND METHODS

We conducted a retrospective and multicenter study based on a review of medical registries of asthmatic patients treated with ICS/LABA combinations (n=2,213) whose medical devices were either dry powder inhalers (DPIs, such as Accuhaler(®), Turbuhaler(®), and NEXThaler(®)) or pressurized metered-dose inhalers (pMDI). Medication compliance included persistence outcomes through 18 months and medication possession ratios. Data on potential confounders of treatment compliance such as asthma exacerbations, comorbidities, demographic characteristics, and health care resource utilization were also explored.

RESULTS

The probability of asthma medication compliance in case of DPIs was lower compared to pMDIs, which suggests that inhaler devices influence inhalation therapies. There were additional confounding factors that were considered as explanatory variables of compliance. A worse measure of airflow obstruction (forced expiration volume in 1 second), comorbidities and general practitioner (GP) consultations more than once per month decreased the probability of compliance. Within comorbidities, alcoholism was positively associated with compliance. Patients of 29-39, 40-50, and 51-61 age groups or suffering from more than two exacerbations during the study period were more likely to comply with their medication regime. The effects of DPIs toward compliance varied with the different DPIs. For instance, Accuhaler(®) had a greater negative effect on compliance compared to Turbuhaler(®) and Nexthaler(®) in cases of patients who suffered exacerbations. We found that GP consultations reduced the probability of medication compliance for patients treated with formoterol/budesonide combination. For retired patients, visiting the GP increased the probability of medication compliance.

CONCLUSION

We concluded that inhaler devices influence patients' compliance for long-term asthma medication. The impact of Accuhaler(®), Turbuhaler(®), and NEXThaler(®) on medication compliance was negative. We also identified some confounders of medication compliance such as patient's age, severity of asthma, comorbidities, and health care costs.

Recent advances in paediatric respiratory medicine

This review highlights important advances in paediatric respiratory medicine since 2014, excluding cystic fibrosis. It focuses mainly on the more common conditions, bronchopulmonary dysplasia, bronchiolitis and preschool wheezing, asthma, pneumonia and sleep, and highlights some of the rarer conditions such as primary ciliary dyskinesia and interstitial lung disease (ILD).

Primary adherence to controller medications for asthma is poor

RATIONALE

Few previous studies have evaluated primary adherence (whether a new prescription is filled within 30 d) to controller medications in individuals with persistent asthma.

OBJECTIVE

To compare adherence to the major controller medication regimens for asthma.

METHODS

This was a retrospective cohort study of enrollees from five large health plans. We used electronic medical data on patients of all ages with asthma who had experienced an asthma-related exacerbation in the prior 12 months. We studied adherence measures including proportion of days covered and primary adherence (first prescription filled within 30 d).

MEASUREMENTS AND MAIN RESULTS

Our population included 69,652 subjects who had probable persistent asthma and were prescribed inhaled corticosteroids (ICSs), leukotriene antagonists (LTRAs), or ICS/long-acting β-agonists (ICS/LABAs). The mean age was 37 years and 58% were female. We found that 14-20% of subjects who were prescribed controller medicines for the first time did not fill their prescriptions. The mean proportion of days covered was 19% for ICS, 30% for LTRA, and 25% for ICS/LABA over 12 months. Using multivariate logistic regression, subjects prescribed LTRA were less likely to be primary adherent than subjects prescribed ICS (odds ratio, 0.82; 95% confidence interval, 0.74-0.92) or ICS/LABA (odds ratio, 0.88; 95% confidence interval, 0.80-0.97). Black and Latino patients were less likely to fill the prescription compared with white patients.

CONCLUSIONS

Adherence to controller medications for asthma is poor. In this insured population, primary adherence to ICSs was better than to LTRAs and ICS/LABAs. Adherence as measured by proportion of days covered was better for LTRAs and ICS/LABAs than for ICSs.

The importance of inhaler devices: the choice of inhaler device may lead to suboptimal adherence in COPD patients

Objective

This study aims to identify factors associated with poor adherence to COPD treatment in patients receiving a fixed-dose combination (FDC) of inhaled corticosteroids and long-acting β₂-agonist (ICS/LABA), focusing on the importance of inhaler devices.

Methods

We conducted a retrospective and multicenter study based on a review of medical registries between 2007 and 2012 of COPD patients (n=1,263) treated with ICS/LABA FDC, whose medical devices were either dry powder inhalers (DPIs) or pressurized metered-dose inhalers (pMDI). Medication adherence included persistence outcomes through 18 months and medication possession ratios. Data on exacerbations, comorbidities, demographic characteristics, and health care resource utilization were also included as confounders of adherence.

Results

The analyses revealed that COPD patients whose medication was delivered through a DPI were less likely to have medication adherence compared to patients with pMDI, after adjusting for confounding factors, especially active ingredients. Younger groups of patients were less likely to be adherent compared to the oldest group. Smoker men were less likely to be adherent compared to women and non-smokers. Comorbidities decreased the probability of treatment adherence. Those patients that visited their doctor once a month were more likely to adhere to their medication regimen; however, suboptimal adherence was more likely to occur among those patients who visited more than three times per month their doctor. We also found that worsening of COPD is negatively associated with adherence.

Conclusion

According to this study, inhaler devices influence patients’ adherence to long-term COPD medication. We also found that DPIs delivering ICS/LABA FDC had a negative impact on adherence. Patients’ clinic and socioeconomic characteristics were associated with adherence.

Patient-reported side effects, concerns and adherence to corticosteroid treatment for asthma, and comparison with physician estimates of side-effect prevalence: a UK-wide, cross-sectional study

Background:

Non-adherence to corticosteroid treatment has been shown to reduce treatment efficacy, thus compromising asthma control.

Aims:

To examine the experiences of treatment side effects, treatment concerns and adherence to inhaled (ICS) and oral corticosteroids (OCS) among people with asthma and to identify the degree of concordance between clinician estimates of side effects and the prevalence reported by patients.

Methods:

Asthma UK members were sent validated questionnaires assessing treatment concerns, experiences of side effects and adherence. Questionnaires measuring clinicians’ estimates of the prevalence of corticosteroid side effects were completed online.

Results:

Completed questionnaires were returned by 1,524 people taking ICS, 233 taking OCS and 244 clinicians (67% of clinicians were primary care nurses). Among people with asthma, 64% of those taking ICS and 88% of those taking OCS reported ⩾1 side effect. People reporting high adherence to ICS (t=−3.09, P<0.005) and those reporting low adherence to OCS (t=1.86, P<0.05; one-tailed test) reported more side effects. There was a disparity between clinicians’ estimates of the frequency of side effects and the frequency reported by people with asthma: e.g., although 46% of people taking ICS reported sore throat, clinicians estimated that this figure would be 10%. Patients who reported side effects had stronger concerns about both ICS (r=0.46, P<0.0001) and OCS (r=0.50, P<0.0001). Concerns about corticosteroids were associated with low adherence to ICS (t=6.90, P<0.0001) and OCS (t=1.71; P<0.05; one-tailed test).

Conclusions:

An unexpectedly large proportion of people with asthma experienced side effects and had strong concerns about their treatment, which compromised adherence. These findings have implications for the design of interventions to optimise asthma control through improved adherence.

Medication adherence and the risk of severe asthma exacerbations: a systematic review

The benefits of drug therapy for asthma have been well established, but adherence to treatment is poor, and this might be associated with an increased risk of asthma exacerbations. The aim of this study was to review the literature on the association between adherence to asthma controller treatment and risk of severe asthma exacerbations in children and adults.

A systematic literature search was performed in PubMed, Embase and Web of Science, from inception until January 2014. Studies were included if data on the association between medication adherence and severe asthma exacerbations were presented. Quality was assessed using a modified version of the Newcastle–Ottawa Scale.

The search yielded 2319 unique publications, of which 23 met the inclusion criteria and underwent data extraction and quality scoring. High levels of heterogeneity across studies with regard to adherence and exacerbation measurements, designs and analysis precluded a formal meta-analysis. Although effect measures varied widely, good adherence was associated with fewer severe asthma exacerbations in high-quality studies.

Good adherence tended to be associated with lower risk of severe asthma exacerbations. Future studies should use standardised methodology to assess adherence and exacerbations, and should consider inhaler competence.

Impact of adherence to treatment with fluticasone propionate/salmeterol in asthma patients

OBJECTIVE

Low adherence with asthma treatment may be associated with suboptimal outcomes and hence create a treatment gap in the real-life setting. The objective of this study was to assess the long-term association between adherence to treatment with fixed-dose fluticasone propionate/salmeterol (FSC) and the risk of exacerbations and health care utilization in patients with asthma.

RESEARCH DESIGN AND METHODS

Observational single cohort study utilizing the Quebec Health Insurance databases. All patients (age >12 years) with a diagnosis of asthma (ICD9-CM 493.xx) between 2001 and 2010 were entered into the study cohort at the time of their first prescription for FSC at any dose. Follow-up continued to the last known claim or death. Adherence to treatment was ascertained as compliance (medication possession ratio ≥80%) and persistence (absence of treatment gap ≥30 days).

MAIN OUTCOME MEASURES

Outcomes assessed were exacerbations defined as one of the following: use of oral corticosteroid (OCS), emergency room (ER) visit for asthma or hospitalization for asthma. Asthma related health care resource utilizations ascertained were number of prescription claims for rescue medications, ER visits, hospitalizations, intensive care unit (ICU) stay, intubations, and general practitioner (GP) and respirologist visits.

RESULTS

A total of 19,126 patients were included in the study. The proportion of compliant and persistent patients were 42.7% and 29.3% respectively. Multivariate logistic regression analyses showed a significantly reduced adjusted odds of exacerbations for compliant (OR = 0.48; 95% CI: 0.44-0.54) and persistent patients (OR = 0.42; 95% CI: 0.38-0.48). Similarly, significantly lower rates of health care utilization were observed for compliant and persistent patients.

CONCLUSIONS

The results of this large population-based study have shown that increased adherence to treatment with FSC is associated with lower risk for exacerbations, lower rescue medication use and lower health care utilization in asthma patients. Despite the typical limitations of an administrative database study including validity of the diagnosis, the fact that compliance and persistence are calculated based on filled claims which does not guarantee that the patients actually took their medications, and the absence of clinical and laboratory data, the findings have implications for physician and patient awareness of the importance of adherence in the management of asthma.

Role of health education and self-action plan in improving the drug compliance in bronchial asthma

BACKGROUND

Considering the prevalence and associated burden of disease due to bronchial asthma, it is mandatory to obtain an optimal control of the disease and to improve outcomes for these patients. But it has been observed that there is very poor adherence to the inhalational therapy which leads to the suboptimal control of the disease.

OBJECTIVES OF THE STUDY

To study the adherence for aerosol therapy in bronchial asthma patients and to assess the impact of health education and self-action plan in improving the compliance to the therapy.

METHODOLOGY

A prospective study was done in a total of 500 bronchial asthma patients over a period of 2 years. Once included in the study, the patients were followed-up for a total of 12 weeks for calculation of nonadherence to the aerosol therapy. In nonadherent patients, we employed various health education strategies to improve the compliance in these cases.

RESULTS

A total of 500 patients of bronchial asthma who were started on aerosol therapy over duration of 2 years were included in the study. At the end of 12 weeks, it was observed that, only 193 patients (38.6%) had regular compliance and 307 patients (61.4%) were noncompliant to aerosol therapy as prescribed for bronchial asthma. Factors that were associated with poor compliance were: Lower educational level status, poor socioeconomic status, cumbersome regimens, dislike of medication, and distant pharmacies. Nondrug factors that reduced the compliance were: Fears about side effects, anger about condition or its treatment, forgetfulness or complacency, and patient's ill attitudes toward health. After employing the various strategies for improving the compliance in these patients, the compliance increased in 176 patients (57.3%) among the earlier defaulted patients, while the remaining 131 patients (42.7%) were found to be noncompliant even after various educational techniques.

CONCLUSION

Noncompliance in asthma management is a fact of life and no single compliance improving strategy probably will be as effective as a good physician-patient relationship. Optimal self-management allowing for optimization of asthma control by adjustment of medications may be conducted by either self-adjustment with the aid of a written action plan or by regular medical review. Individualized written action plans based on peak expiratory flow are equivalent to action plans based on symptoms.

Comparing usability of NEXThaler(®) with other inhaled corticosteroid/long-acting β2-agonist fixed combination dry powder inhalers in asthma patients

BACKGROUND

Inhaler mishandling is a common issue among patients suffering from asthma and is associated with poor clinical outcomes and greater consumption of health-care resources. Ease of use can improve inhaler technique and, possibly, patients' preference for their inhaler device, which in turn may lead to better adherence to therapy.

METHODS

This study investigated usability characteristics of NEXThaler(®) versus two other dry powder inhalers (DPIs; Diskus(®) and Turbuhaler(®)). Sixty-six adult patients with asthma (mean age 42.9±17.7 years) and with no previous experience of using a DPI were included in a randomized crossover comparison of the three devices. The main measures of usability were the number of steps failed for each device and the number of people who were able to use the device successfully (effectiveness), the time it took patients to set up the device and the time to read the instructions for use (IFU; efficiency), and patient preferences (satisfaction). Inhaler technique was evaluated after the IFU leaflet was read.

RESULTS

NEXThaler was found to be superior to the other two DPIs in terms of the number of device use failures (p<0.001), time to set up (p<0.001), and time to read IFU (p<0.001). Additionally, the proportion of participants who completed a successful inhalation without any errors at all was significantly higher for NEXThaler than for Diskus and Turbuhaler (p<0.001). Patients rated NEXThaler as the easiest to use and most preferred inhaler to own (p<0.001).

CONCLUSIONS

NEXThaler displayed better usability compared with Diskus and Turbuhaler. The improved usability and higher satisfaction with the device may contribute to increased patient adherence to asthma treatment.

Asthma outcomes are poor among older adults with low health literacy

OBJECTIVE

To examine the association of health literacy (HL) with asthma outcomes among older asthmatics.

METHODS

The study included adults ages ≥60 with moderate to severe asthma in New York City and Chicago. We assessed asthma control with the Asthma Control Questionnaire (ACQ) and the percent predicted forced expiratory volume at 1 s (FEV1) by spirometry, hospitalizations and emergency department (ED) visits in the past 6 months, and quality of life. HL was assessed with the Short Test of Functional Health Literacy in Adults (S-TOFHLA). Multivariate logistic regression models controlled for age, sex, race, income, general health and years with asthma.

RESULTS

Among 433 individuals, 36% had low HL, 55% were over age 65, 38% were Hispanic and 22% were black. Poor asthma control was reported by 40% and 32% had FEV1 <70% of predicted; 9% had a hospital stay, 23% had an ED and 38% had poor quality of life. In multivariable analysis, individuals with low HL were more likely to have FEV1 <70% predicted (odds ratio [OR] 2.34, 95% confidence interval [CI] 1.39-3.94, p = 0.001), hospitalizations (OR 2.53, 95% CI 1.17-5.49, p = 0.02) and ED visits for asthma (OR 1.81, 95% CI 1.05-3.10, p = 0.03). There were no differences in self-reported asthma control and quality of life.

CONCLUSIONS

Low HL is associated with poor asthma control by objective measure, and greater likelihood of ED visits and hospitalization. HL is a modifiable target for interventions to improve asthma outcomes in the elderly.

Potential negative consequences of non-consented switch of inhaled medications and devices in asthma patients

BACKGROUND

Asthma requires individually tailored and careful management to control and prevent symptoms and exacerbations. Selection of the most appropriate treatment is dependent on both the choice of drugs and inhaler device; however, financial pressures may result in patients being switched to alternative medications and devices in an attempt to reduce costs.

AIM

This review aimed to examine the published literature in order to ascertain whether switching a patient's asthma medications or device negatively impacts clinical and economic outcomes.

MATERIALS AND METHODS

A literature search of MEDLINE (2001-13 September 2011) was conducted to identify English-language articles focused on the direct impact of switching medications and inhaler devices and switching from fixed-dose combination to monocomponent therapy via separate inhalers in patients with asthma; the indirect impacts of switching were also assessed.

RESULTS

Evidence showed that non-consented switching of medications and inhalers in patients with asthma can be associated with a range of negative outcomes, at both individual and organisational levels. Factors that reduce adherence may lead to compromised symptom control resulting in increased healthcare resource utilisation and poorer patient quality of life.

DISCUSSION

The consequences of a non-consented switch should be weighed carefully against arguments supporting an inhaler switch without the patient's consent for non-medical/budgetary reasons, such as potential reductions in initial acquisition costs, which may be associated with subsequent additional healthcare needs.

CONCLUSION

Given the increasing pressure for reduced costs and efficient allocation of limited healthcare resources, an additional investment in ensuring high medication adherence may lead to greater savings due to a potentially decreased demand for healthcare services. In contrast, savings achieved in acquisition costs may result in a greater net loss due to increased healthcare consumption caused by decreased asthma control.

Estimating the information gap between emergency department records of community medication compared to on-line access to the community-based pharmacy records

Objective

Errors in community medication histories increase the risk of adverse events. The objectives of this study were to estimate the extent to which access to community-based pharmacy records provided more information about prescription drug use than conventional medication histories.

Materials and methods

A prospective cohort of patients with public drug insurance who visited the emergency departments (ED) in two teaching hospitals in Montreal, Quebec was recruited. Drug lists recorded in the patients’ ED charts were compared with pharmacy records of dispensed medications retrieved from the public drug insurer. Patient and drug-related predictors of discrepancies were estimated using general estimating equation multivariate logistic regression.

Results

613 patients participated in the study (mean age 63.1 years, 59.2% women). Pharmacy records identified 41.5% more prescribed medications than were noted in the ED chart. Concordance was highest for anticoagulants, cardiovascular drugs and diuretics. Omissions in the ED chart were more common for drugs that may be taken episodically. Patients with more than 12 medications (OR 2.92, 95% CI 1.71 to 4.97) and more than one pharmacy (OR 3.85, 95% CI 1.80 to 6.59) were more likely to have omissions in the ED chart.

Discussion

The development of health information exchanges could improve the efficiency and accuracy of information about community medication histories if they enable automated access to dispensed medication records from community pharmacies, particularly for the most vulnerable populations with multiple morbidities.

Conclusions

Pharmacy records identified a substantial number of medications that were not in the ED chart. There is potential for greater safety and efficiency with automated access to pharmacy records.

Adherence to inhaled therapies, health outcomes and costs in patients with asthma and COPD

Suboptimal adherence to pharmacological treatment of asthma and chronic obstructive pulmonary disease (COPD) has adverse effects on disease control and treatment costs. The reasons behind non-adherence revolve around patient knowledge/education, inhaler device convenience and satisfaction, age, adverse effects and medication costs. Age is of particular concern given the increasing prevalence of asthma in the young and increased rates of non-adherence in adolescents compared with children and adults. The correlation between adherence to inhaled pharmacological therapies for asthma and COPD and clinical efficacy is positive, with improved symptom control and lung function shown in most studies of adults, adolescents and children. Satisfaction with inhaler devices is also positively correlated with improved adherence and clinical outcomes, and reduced costs. Reductions in healthcare utilisation are consistently observed with good adherence; however, costs associated with general healthcare and lost productivity tend to be offset only in more adherent patients with severe disease, versus those with milder forms of asthma or COPD. Non-adherence is associated with higher healthcare utilisation and costs, and reductions in health-related quality of life, and remains problematic on an individual, societal and economic level. Further development of measures to improve adherence is needed to fully address these issues.

Asthma beliefs are associated with medication adherence in older asthmatics

BACKGROUND

Empirical research and health policies on asthma have focused on children and young adults, even though asthma morbidity and mortality are higher among older asthmatics.

OBJECTIVE

To explore the relationship of asthma-related beliefs and self-reported controller medication adherence in older asthmatics.

DESIGN

An observational study of asthma beliefs and self-management among older adults.

PARTICIPANTS

Asthmatics ages ≥ 60 years (N = 324, mean age 67.4 ± 6.8, 28 % white, 32 % black, 30 % Hispanic) were recruited from primary care practices in New York City and Chicago.

MAIN MEASURES

Self-reported controller medication adherence was assessed using the Medication Adherence Report Scale. Based on the Common Sense Model of Self-Regulation, patients were asked if they believe they only have asthma with symptoms, their physician can cure their asthma, and if their asthma will persist. Beliefs on the benefit, necessity and concerns of treatment use were also assessed. Multivariate logistic regression was used to examine the association of beliefs with self-reported medication adherence.

KEY RESULTS

The majority (57.0 %) of patients reported poor adherence. Poor self-reported adherence was more common among those with erroneous beliefs about asthma illness and treatments, including the "no symptoms, no asthma" belief (58.7 % vs. 31.7 %, respectively, p < 0.001), "will not always have asthma" belief (34.8 % vs. 12.5 %, p < 0.001), and the "MD can cure asthma" belief (21.7 % vs. 9.6 %, p = 0.01). Adjusting for illness beliefs, treatment beliefs and demographics, patients with a "no symptoms, no asthma" belief had lower odds of having good self-reported adherence (odds ratio [OR] 0.45, 95 % confidence interval [CI] 0.23-0.86), as did those with negative beliefs about the benefits (OR 0.73, 95 % CI 0.57-0.94) and necessity (OR 0.89, 95 % CI 0.83-0.96) of treatment.

CONCLUSIONS

Illness and treatment beliefs have a strong influence on self-reported medication adherence in older asthmatics. Interventions to improve medication adherence in older asthmatics by modifying illness and treatment beliefs warrant study.

Association of asthma education with asthma control evaluated by asthma control test, FEV1, and fractional exhaled nitric oxide

BACKGROUND

Asthma education is an important adjunct for asthma control although the way asthma education affects asthma outcomes is poorly understood. The asthma control test (ACT), forced expiratory volume in 1 s (FEV(1)), and fractional exhaled nitric oxide (FeNO) have all been used as markers of asthma control. However, the use of FeNO as a surrogate marker remains controversial.

OBJECTIVES

(i) To examine whether asthma education is associated with asthma control; (ii) to compare absolute levels and changes of ACT, FEV(1), and FeNO over a year; and (iii) to evaluate whether FeNO can be used as an additional marker of asthma control.

METHODS

Fifty asthmatics with poor adherence (12 mild, 21 moderate, and 17 severe) received asthma education at study entry. Medications were unchanged for the first 3 months, and ACT, FEV(1), and FeNO measurements were recorded at entry, 3, 6, and 12 months. Asthma control was assessed at each visit and patients were categorized as either "stable" or "unstable" asthmatics according to the global initiative for asthma (GINA) guidelines.

RESULTS

A significant decrease in FeNO and increase in ACT score were noted in the stable asthmatic group at 3 months (p < .001), and this persisted over 12 months. Significant correlations were seen between changes (Δ) in FeNO, ACT, and FEV(1) over time. However, significant correlations between the absolute levels were not maintained over 12 months. A decrease of ≥18.6% in FeNO and a ≥3-point increase in ACT score (sensitivity: 80% and 73.3% and specificity: 83.3% and 87.5%, respectively) were associated with stable asthma control although the absolute levels were not.

CONCLUSIONS

Asthma education may be useful to achieve stable control. In addition, changes rather than absolute levels of FeNO and ACT may be better markers of asthma control.

Asthma/COPD drugs reflecting disease prevalence, patient adherence and persistence

The aim of this review is to discuss the methodological issues involved in using pharmacy-record databases of drug sales in pharmacoepidemiology and to illustrate the usefulness of such data in estimating disease prevalence, patient adherence and persistence to therapy. Recent studies show that asthma/chronic obstructive pulmonary disease (COPD) prevalence increases with age. The volume of acquired asthma/COPD drugs per patient also increases with age and was approximately 2.5-times higher for patients aged 60-69 years compared with patients aged 20-29 years. Despite this, there is a comparatively low interest in asthma/COPD research involving elderly individuals. Published asthma/COPD-prevalence data and drug-treatment-prevalence data correspond reasonably well. Short- as well as long-term studies on drug acquisition indicate that approximately a third of patients have drugs available to cover at least 80% of the prescribed treatment time. Only approximately a tenth of the patients acquired steroids or steroid combinations, corresponding to one daily defined dose per day over a 5-year treatment period. It is probable that asthma/COPD is undertreated in all age groups.

Environmental Exposure and Nonadherence with Medicines Directly Correlate with Exacerbations and Hospitalization for Asthma: A Population-Based Survey from UAE

Acute severe exacerbation of asthma is directly related with the uncontrolled asthma including noncompliance with the medicines and exposure to the environmental factors. To our knowledge, none of the community-based study has explored the prevalence of asthma and other factors (namely, pattern of symptoms, environmental/occupational/housing/behavioral pattern/misperception about asthma, and educational factors) contributing to the exacerbation of asthma. We also studied the nonadherence issues related to the management of asthma in the United Arab Emirates (UAE). By using European Community Respiratory Health Survey (ECRHS) questionnaires and pooled data from AIRGNE (UAE) study, we aimed to determine the above-mentioned factors in the general population by means of a cross-sectional assessment of a random sample of 1,229 participants of which 62.97% were male and 20.01% were UAE nationals, with a mean age (±SD) of 32.9 (±14.1) years. Prevalence of individual respiratory symptoms from the ECRHS questionnaire in all participants ranged from 8 to 10%, while those participants aged 20–44 years presented a lower prevalence in all symptoms (P<0.05). Conclusion. Certain specific persistent environmental factor along with nonadherence to the controller medicines is a significant factor leading to uncontrolled asthma with consequent exacerbations, morbidity/mortality, and health care cost in UAE.

The predictors of poorly controlled asthma in elderly

Purpose

To evaluate asthma control in elderly individuals and identify the factors that predict poor control.

Methods

A retrospective, observational study evaluating 108 elderly individuals with asthma (59 females: ≥60 years, mean age: 70.5 years) was conducted at Ajou University Hospital from October 2010 to March 2011. Subjects were classified into two groups according to scores on the asthma control test (ACT). Group I consisted of 38 patients with ACT scores ≤19 (poor controllers) and group II included 70 patients with ACT scores >19 (controllers). Clinical data was analyzed. Spirometry was performed, and the ACT and asthma quality-of-life survey were completed. Medication possession ratios were calculated to evaluate compliance.

Results

Of the 108 enrolled subjects, 54.6% were female, 7.5% were obese, and 49.0% were atopic. The mean age of the patients was 70.5, and the average of time patients had suffered from asthma was 15.5 years. Comorbid conditions were found in more than 80% of the patients. Allergic rhinitis was most common comorbid condition; this was followed by cardiovascular disease and degenerative arthritis (76.9%, 65.7%, and 51.9%, respectively). Many patients (35.2%) were in poorly controlled states characterized by significantly lower asthma quality of life scores (P<0.001) and higher admission rates (P=0.034). Multivariate logistic regression analysis showed that a history of pulmonary tuberculosis was a predictor of poorly controlled asthma in elderly individuals even after adjusting for age, sex, smoking, lung function and other comorbidities (OR=4.70, CI=1.06-20.81, P=0.042).

Conclusions

The asthma of more than one-third of elderly individuals with this condition was poorly controlled, and a history of pulmonary tuberculosis may have contributed to this outcome. Proper evaluation and management of comorbid conditions in elderly patients with asthma is essential for the achievement of better control of the disease and a higher quality of life for those who suffer from it.

Quantifying the proportion of severe asthma exacerbations attributable to inhaled corticosteroid nonadherence

BACKGROUND

Asthma is an inflammatory condition often punctuated by episodic symptomatic worsening, and accordingly, patients with asthma might have waxing and waning adherence to controller therapy.

OBJECTIVE

We sought to measure changes in inhaled corticosteroid (ICS) adherence over time and to estimate the effect of this changing pattern of use on asthma exacerbations.

METHODS

ICS adherence was estimated from electronic prescription and fill information for 298 participants in the Study of Asthma Phenotypes and Pharmacogenomic Interactions by Race-Ethnicity. For each patient, we calculated a moving average of ICS adherence for each day of follow-up. Asthma exacerbations were defined as the need for oral corticosteroids, an asthma-related emergency department visit, or an asthma-related hospitalization. Proportional hazard models were used to assess the relationship between ICS medication adherence and asthma exacerbations.

RESULTS

Adherence to ICS medications began to increase before the first asthma exacerbation and continued afterward. Adherence was associated with a reduction in exacerbations but was only statistically significant among patients whose adherence was greater than 75% of the prescribed dose (hazard ratio, 0.61; 95% CI, 0.41-0.90) when compared with patients whose adherence was 25% or less. This pattern was largely confined to patients whose asthma was not well controlled initially. An estimated 24% of asthma exacerbations were attributable to ICS medication nonadherence.

CONCLUSIONS

ICS adherence varies in the time period leading up to and after an asthma exacerbation, and nonadherence likely contributes to a large number of these exacerbations. High levels of adherence are likely required to prevent these events.