Measuring the effect of asthma control on exacerbations and health resource use

Long-Term Cost-Effectiveness of Digital Inhaler Adherence Technologies in Difficult-to-Treat Asthma

BACKGROUND

Digital inhalers can monitor inhaler usage, support difficult-to-treat asthma management, and inform step-up treatment decisions yet their economic value is unknown, hampering wide-scale implementation.

OBJECTIVE

We aimed to assess the long-term cost-effectiveness of digital inhaler-based medication adherence management in difficult-to-treat asthma.

METHODS

A model-based cost-utility analysis was performed. The Markov model structure was determined by biological and clinical understanding of asthma and was further informed by guideline-based assessment of model development. Internal and external validation was performed using the Assessment of the Validation Status of Health-Economic (AdViSHE) tool. The INCA (Inhaler Compliance Assessment) Sun randomized clinical trial data were incorporated into the model to evaluate the cost-effectiveness of digital inhalers. Several long-term clinical case scenarios were assessed (reduced number of exacerbations, increased asthma control, introduction of biosimilars [25% price-cut on biologics]).

RESULTS

The long-term modelled cost-effectiveness based on a societal perspective indicated 1-year per-patient costs for digital inhalers and usual care (ie, regular inhalers) of €7,546 ($7,946) and €10,752 ($11,322), respectively, reflecting cost savings of €3,207 ($3,377) for digital inhalers. Using a 10-year intervention duration and time horizon resulted in cost savings of €26,309 ($27,703) for digital inhalers. In the first year, add-on biologic therapies accounted for 69% of the total costs in the usual care group and for 49% in the digital inhaler group. Scenario analyses indicated consistent cost savings ranging from €2,287 ($2,408) (introduction biosimilars) to €4,581 ($4,824) (increased control, decreased exacerbations).

CONCLUSIONS

In patients with difficult-to-treat asthma, digital inhaler-based interventions can be cost-saving in the long-term by optimizing medication adherence and inhaler technique and reducing add-on biologic prescriptions.

Cost-effectiveness of single-inhaler extrafine beclometasone dipropionate/formoterol fumarate/glycopyrronium in patients with uncontrolled asthma in England

BACKGROUND

In patients with asthma that is uncontrolled by a medium- or high-dose inhaled corticosteroid (ICS) plus long-acting β₂-agonist (LABA), a maintenance therapy option is the addition of a long-acting muscarinic agonist, either via multiple inhalers, or single-inhaler triple therapy (SITT). One SITT is the extrafine formulation of beclometasone dipropionate/formoterol fumarate/glycopyrronium (BDP/FF/G). We used data from two 52-week clinical trials (TRIMARAN and TRIGGER), both conducted in adults with asthma uncontrolled by ICS/LABA, to investigate the cost-effectiveness of BDP/FF/G.

METHODS

A Markov cohort state transition model (focusing on exacerbations) was used to investigate the cost-effectiveness of medium- or high-dose BDP/FF/G vs medium- or high-dose BDP/FF, and high-dose BDP/FF/G vs high-dose BDP/FF + tiotropium. The model analysed cost, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER), and was developed from the England National Health Service perspective (2020 costs). Uncertainty of the inputs was estimated using one-way and probabilistic sensitivity analyses.

RESULTS

Both medium- and high-dose BDP/FF/G were cost-effective vs BDP/FF, with ICERs of £12,224 and £15,587 per QALY gained. High-dose BDP/FF/G was dominant vs BDP/FF + tiotropium, as it was both cheaper and gained QALYs. Sensitivity analyses were consistent with the base model: medium- and high-dose BDP/FF/G had 94.3% and 88.3% likelihoods to be cost-effective vs BDP/FF; high-dose BDP/FF/G had 100% likelihood to be a dominant strategy vs BDP/FF + tiotropium.

CONCLUSIONS

Both medium- and high-dose BDP/FF/G were cost-effective vs medium- and high-dose BDP/FF in adults with asthma that was uncontrolled by ICS/LABA. In addition, high-dose BDP/FF/G was a dominating strategy to high-dose BDP/FF + tiotropium.

CLINICALTRIALS

GOV: NCT02676076 and NCT02676089.

Nocturnal Cough and Sleep Quality to Assess Asthma Control and Predict Attacks

Introduction

Objective markers for asthma, that can be measured without extra patient effort, could mitigate current shortcomings in asthma monitoring. We investigated whether smartphone-recorded nocturnal cough and sleep quality can be utilized for the detection of periods with uncontrolled asthma or meaningful changes in asthma control and for the prediction of asthma attacks.

Methods

We analyzed questionnaire and sensor data of 79 adults with asthma. Data were collected in situ for 29 days by means of a smartphone. Sleep quality and nocturnal cough frequencies were measured every night with the Pittsburgh Sleep Quality Index and by manually annotating coughs from smartphone audio recordings. Primary endpoint was asthma control assessed with a weekly version of the Asthma Control Test. Secondary endpoint was self-reported asthma attacks.

Results

Mixed-effects regression analyses showed that nocturnal cough and sleep quality were statistically significantly associated with asthma control on a between- and within-patient level (p < 0.05). Decision trees indicated that sleep quality was more useful for detecting weeks with uncontrolled asthma (balanced accuracy (BAC) 68% vs 61%; Δ sensitivity −12%; Δ specificity −2%), while nocturnal cough better detected weeks with asthma control deteriorations (BAC 71% vs 56%; Δ sensitivity 3%; Δ specificity −34%). Cut-offs using both markers predicted asthma attacks up to five days ahead with BACs between 70% and 75% (sensitivities 75 - 88% and specificities 57 - 72%).

Conclusion

Nocturnal cough and sleep quality have useful properties as markers for asthma control and seem to have prognostic value for the early detection of asthma attacks. Due to the limited study duration per patient and the pragmatic nature of the study, future research is needed to comprehensively evaluate and externally validate the performance of both biomarkers and their utility for asthma self-management.

Healthcare resource utilization, expenditures, and productivity in patients with asthma with and without allergies

Objective: To compare healthcare resource utilization (HCRU), healthcare expenditures, and work productivity and activity impairment within a general asthma population with persistent asthma and evidence of allergy (PA-EA) and persistent asthma with no evidence of allergy (PA-NEA).Methods: We conducted a retrospective analysis of survey responses and claims from the Observational Study of Asthma Control and Outcomes (OSACO) study. Eligible patients with persistent asthma aged ≥12 years were sent four surveys over 15 months. Regression models were used to assess the association between: (1) PA-EA (defined as a positive response to a survey question about hay fever/seasonal allergies AND ≥1 diagnostic code for atopic conditions) and HCRU and expenditures; and (2) PA-EA and Work Productivity and Activity Impairment (WPAI)-Asthma questionnaire scores (vs. PA-NEA).Results: Adjusted data showed that, vs. PA-NEA (n = 312), patients with PA-EA (n = 971) incurred 1.34-times more all-cause prescriptions (95% confidence interval [CI], 1.20-1.48), $132.79 higher prescription costs (95% CI, $22.03-243.56), and $926.11 higher all-cause total healthcare costs (95% CI, $279.67-1572.54), per 4-month period. Patients with PA-EA were 4.1% less productive while working (95% CI, 3.75-4.48%) and experienced a 6.5% reduction in all activities (95% CI, 6.11-6.88%) vs. those with PA-NEA.Conclusions: Patients with PA-EA had greater HCRU, healthcare expenditures, and lower productivity compared with those patients with PA-NEA. These results highlight the burden of atopy in patients with persistent asthma and underscore the importance of allergic endotype identification for more vigilant disease management.

Association Between Pulmonary Function and Asthma Symptoms

BACKGROUND

FEV₁ as a percentage of predicted (FEV₁%pred) is commonly measured in asthma clinical studies; however, reports vary on its association with asthma control instruments evaluating symptoms.

OBJECTIVE

Assess the association between FEV₁%pred and Asthma Control Questionnaire (ACQ) scores in a managed-care population with persistent asthma.

METHODS

Retrospective analysis of survey responses and spirometry results of patients (aged ≥12 years) with persistent asthma from the Observational Study of Asthma Control and Outcomes was done. Eligible patients received 4 identical surveys including the 5-item ACQ (ACQ-5)/6-item ACQ (ACQ-6) and completed spirometry in parallel. Longitudinal analyses, comparisons of change over time, and fixed- and random-effects regression analyses were conducted, with/without adjustment for covariates.

RESULTS

There were 1748 survey responses with valid spirometry results. In unadjusted models, coefficients for ACQ-5/ACQ-6 scores were not statistically significant and coefficient of determination (R²) was low (0.03). When adjusted for covariates, ACQ-5 and ACQ-6 scores were significantly associated with FEV₁%pred (P < .001) and R² increased to 0.11 and 0.12, respectively. In adjusted models, every 1-point increase in ACQ-5 and ACQ-6 scores was associated with a 1.7% and 1.9% decrease, respectively, in FEV₁%pred. Change in FEV₁%pred and change in ACQ-5/ACQ-6 scores were not significantly associated in regressions with/without covariates.

CONCLUSIONS

The weak and statistically insignificant association between FEV₁%pred and ACQ-5/ACQ-6 scores in unadjusted models suggests a high degree of unexplained variation between these measures. Results support the use of both symptoms and pulmonary function, rather than relying on one measure alone, to assess asthma control in clinical care and outcomes studies.

Estimating asthma control questionnaire (ACQ) scores from claims data

BACKGROUND

Asthma control is the main focus of treatment guidelines. Valid instruments such as the Asthma Control Questionnaire (ACQ) require prospective survey. These surveys may be challenging for large population health applications.

OBJECTIVE

To develop an algorithm for estimating ACQ-5 scores from commonly available claims data.

METHODS

Data was derived from four prospective surveys including the ACQ-5 combined with retrospective claims of Kaiser Permanente of Colorado (KPCO) patients. The statistical approach consisted of derivation and validation of a prediction algorithm including medical and pharmacy claims data using stepwise regression elimination. Validation was conducted by estimating mean squared error (MSE) and mean absolute error (MAE) in one hundred split-sample iterations. Ordinary least squares (OLS), Tobit and Median regression were used.

RESULTS

There were 2,657 individuals with valid ACQ-5 scores, claims and eligibility at baseline. The following had statistically significant associations with ACQ-5 scores: gender, use of oral corticosteroids and short-acting beta agonists, the number of asthma drug classes, and emergency and outpatient visits. Average MSE and MAE were similar for the estimation and validation samples.

CONCLUSION

This research provides preliminary results of the feasibility of predicting ACQ-5 scores using commonly available medical and pharmacy claims data. The resulting algorithm may facilitate public health and population level analyses of asthma control. Future studies in different populations will be important to validate the algorithm.

The national burden of poorly controlled asthma, school absence and parental work loss among school-aged children in the United States

OBJECTIVE

The degree of poorly controlled asthma and its association with missed school days and parental missed work days is not well understood.

METHODS

This was a retrospective analysis of missed school days and missed work days for school-aged children (SAC; aged 6-17) and their caregivers in the nationally representative 2007-2013 Medical Expenditure Panel Survey (MEPS). Indicators of poor asthma control included: exacerbation in previous 12 months; use of >3 canisters of short-acting beta agonist (SABA) in 3 months; and annual asthma-specific (AS) Emergency Department (ED) or inpatient (IP) visits. Negative binomial regression was used for missed school days, and a Heckman two-step selection model was used for missed work days. All analyses controlled for sociodemographics and other covariates.

RESULTS

There were 44,320 SAC in MEPS, of whom 5,890 had asthma. SAC with asthma and an indicator of poor control missed more school days than SAC without asthma: exacerbation (1.8 times more; p < 0.001); >3 canisters SABA (2.7 times more; p < 0.001) and ED/IP visit (3.8 times more; p < 0.001). The parents/caregivers of SAC with asthma and an exacerbation missed 1.2 times more work days (p < 0.05), while those with SAC with asthma and an ED/IP visit missed 1.8 times more work days (p < 0.01) than the parents of SAC without asthma.

CONCLUSIONS

This study provides evidence of the significant national burden of poorly controlled asthma due to missed school and work days in the United States. More effective and creative asthma management strategies, with collaboration across clinical, community and school-based outreach, may help address this burden.

Asthma Cost-Effectiveness Analyses: Are We Using the Recommended Outcomes in Estimating Value?

BACKGROUND

Asthma medication cost-effectiveness analyses (CEAs) lack the qualitative assessment regarding whether they capture the National Institutes for Health (NIH) 2012 recommended outcomes necessary to allow robust cross-study comparisons.

OBJECTIVE

We aimed to assess the current asthma outcomes used in CEAs and recommend a direction for improvement.

METHODS

We performed a systematic search using electronic databases including PubMed, EMBASE, Tufts CEA registry, Cochrane, and NHSEED from January 2010 through December 2015. Key words included (1) cost-effectiveness, cost-utility, economic evaluation, health economics, or cost-benefit AND (2) asthma. All CEA studies evaluating 1 or more asthma medication were included. Authors assessed each CEA study with respect to asthma-specific NIH outcome recommendations including core (hospitalizations, emergency department visits, outpatient visits, medication, interventions costs), supplemental (visit categories and work/school absence), and emerging (academic/job-related) asthma outcomes. Besides outcomes of each CEA, issues that could prevent robust cross-study comparison were identified and thematically summarized.

RESULTS

A total of 12 pre-NIH and 14 post-NIH recommendation CEAs were included. Eleven (91.7%) and 14 (100%) of the pre-/post-NIH studies included at least 1 core outcome, respectively. Of the 26 total studies, 7 (26.9%) included asthma-specific outpatient visit categories, 6 (23.1%) included asthma school or work absences, 5 (19.2%) included respiratory health care use, and none of the studies included emerging outcomes. Other issues that hamper cross-study comparison include lack of standardized cost data, time frames, quality-of-life measures, and incorporation of adherence.

CONCLUSIONS

Although the use of NIH-recommended asthma core outcomes has improved, there is still room for improvement in using supplemental and emerging outcomes. To allow robust cross-study comparisons, future work should focus on further standardizing of data sources and methods.

Exploring asthma control cutoffs and economic outcomes using the Asthma Control Questionnaire

BACKGROUND

Understanding the effect of worsening asthma control on expenditures and health resource utilization (HRU) is important.

OBJECTIVE

To explore the association of economic outcomes with asthma control cutoffs and longitudinal changes on the Asthma Control Questionnaire 5 (ACQ-5).

METHODS

The Observational Study of Asthma Control and Outcomes was a survey of patients with persistent asthma who were patients of Kaiser Colorado, including claims-based HRU. Patients completed the ACQ-5 three times during 1 year between April 2011 and June 2012. The ACQ-5 cutoffs that indicated control were assessed in cross-sectional analyses. Longitudinal changes in control were explored: controlled (ACQ-5 score <0.75), indeterminate (ACQ-5 score 0.75 to <1.5), not well controlled (ACQ-5 score 1.5 to <3.0), and very poorly controlled (ACQ-5 score ≥3.0). Analyses used generalized linear models with log link (expenditures) and negative binomial regression (HRU).

RESULTS

There were 6,666 completed surveys (1,799 individuals completed all 3 survey waves). In the cross-sectional analyses, compared with an ACQ-5 score less than 0.5, individuals with ACQ-5 scores of 4 to 4.5 incurred 7.2 times the number of oral corticosteroid prescriptions, 4.3 times the number of emergency department visits, 6 times the number of inpatient visits, 10.4 times the number of asthma-specific emergency department visits, 4.58 times the number of asthma-specific inpatient visits, and $2,892 more in all-cause and $1,877 in asthma-specific expenditures during 4 months. In the longitudinal change analyses, individuals who improved from an ACQ-5 of 3.0 or greater to less than 0.75 incurred $6,023 less in asthma-specific expenditures during 4 months than those remaining at an ACQ-5 score of 3.0 or higher.

CONCLUSION

Results provide preliminary economic data on possible control cutoffs for the ACQ-5. Improving asthma control over time may result in significant savings that may justify financial investments designed to improve control.

Advances in asthma 2015: Across the lifespan

In 2015, progress in understanding asthma ranged from insights to asthma inception, exacerbations, and severity to advancements that will improve disease management throughout the lifespan. 2015's insights to asthma inception included how the intestinal microbiome affects asthma expression with the identification of specific gastrointestinal bacterial taxa in early infancy associated with less asthma risk, possibly by promoting regulatory immune development at a critical early age. The relevance of epigenetic mechanisms in regulating asthma-related gene expression was strengthened. Predicting and preventing exacerbations throughout life might help to reduce progressive lung function decrease and disease severity in adulthood. Although allergy has long been linked to asthma exacerbations, a mechanism through which IgE impairs rhinovirus immunity and underlies asthma exacerbations was demonstrated and improved by anti-IgE therapy (omalizumab). Other key molecular pathways underlying asthma exacerbations, such as cadherin-related family member 3 (CDHR3) and orosomucoid like 3 (ORMDL3), were elucidated. New anti-IL-5 therapeutics, mepolizumab and reslizumab, were US Food and Drug Administration approved for the treatment of patients with severe eosinophilic asthma. In a clinical trial the novel therapeutic inhaled GATA3 mRNA-specific DNAzyme attenuated early- and late-phase allergic responses to inhaled allergen. These current findings are significant steps toward addressing unmet needs in asthma prevention, severity modification, disparities, and lifespan outcomes.

Asthma exacerbations: risk factors for hospital readmissions

OBJECTIVE

The aim of our study is to analyse hospital readmissions due to asthma, as well as the factors associated with their increase.

STUDY DESIGN

We carried out a retrospective study including all admissions of patients over 18 years old due to exacerbation of asthma occurring in our hospital between the years 2000 and 2010.

METHODS

The data were gathered by two members of the research team, by reviewing the clinical records. The first hospital admission of each patient was included for this study. An early readmission (ER) was defined as that which occurred in the following 15 days after hospital discharge and late readmission (LR) to that occurring from 16 days after discharge.

RESULTS

This study included 2166 hospital admissions and 1316 patients, with a mean age of 62.6 years. Of the 1316 patients analysed, 36 (2.7%) had one ER and 313 (23.8%) one LR. The only factor independently associated with a higher probability of an ER was poor lung function. A higher probability of LR was associated with a greater severity of the asthma (OR: 17.8, for severe asthma versus intermittent asthma), to have had any hospital admission in the previous year (OR: 3.5) and the use of a combination of ICS-LABA as maintenance treatment.

CONCLUSIONS

About 25% of the patients in our area admitted to hospital due to asthma exacerbation had repeat episodes of hospitalisation.

Measurement of utility in asthma: evidence indicating that generic instruments may miss clinically important changes

BACKGROUND

Accurate assessment of preference-based health-related quality of life is important in determining the value of asthma interventions.

OBJECTIVE

To examine the sensitivity and responsiveness of the EQ-5D and the AQL-5D to differences in asthma control measured by the Asthma Control Questionnaire (ACQ-5).

METHODS

The Observational Study of Asthma Control and Outcomes was a prospective survey of persistent asthma patients ≥12 years old in Kaiser Colorado. Patients received a survey three times in 1 year, including the ACQ-5, AQL-5D and EQ-5D-3L (including VAS). Censored Least Absolute Deviations (CLAD) and logistic regression were used, controlling for sociodemographics and smoking.

RESULTS

There were 6666 completed surveys (1799 individuals completed all three survey waves). After controlling for covariates, each one-point increase in ACQ-5 was associated with a decrease of 0.066, 0.058, 0.074 and 6.12 in EQ-5D(US), EQ-5D(UK), AQL-5D and VAS scores. Uncontrolled asthma (ACQ-5 > 1.5) was associated with a decrease of 0.15, 0.17, 0.11 and 10, respectively (vs. ACQ ≤ 1.5). AQL-5D scores were statistically significantly different across categories of ACQ-5 scores of 0.5 (the minimum clinically important difference [MCID]), while EQ-5D scores were not significant across most categories. The AQL-5D appeared more robust to changes in control over time (responsiveness) compared to EQ-5D-3L.

CONCLUSION

The AQL-5D appears more responsive to changes in asthma control over time and more sensitive to detecting differences corresponding to the ACQ-5 MCID than the EQ-5D-3L. Using the EQ-5D-3L without an asthma-specific measure such as the AQL-5D may miss clinically important changes in asthma control.