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

Testing the psychometric characteristics of EQ-5D-5L and respiratory bolt-ons using a sample of the Australian population

PURPOSE

The EQ-5D has been used to assess health related quality of life (HRQoL) in respiratory conditions. However, the core descriptive system may not be sensitive to all the HRQoL impacts of these conditions. To increase the sensitivity of the descriptive system, two respiratory specific bolt-ons, have been developed. Psychometric assessment of the bolt-ons in comparison to other validated instruments is required to facilitate their use. Therefore, the aim of this study is to test the psychometric characteristics of the EQ-5D-5L + R using a large dataset collected in Australia.

METHODS

A cross-sectional online survey was used to recruit adult respondents (≥ 18 years) representative of the Australian population. Descriptive and psychometric analyses were used to understand the performance of the EQ-5D-5L and bolt-ons in comparison to other validated instruments. The construct validity was estimated using correlations. Known-group validity was tested to determine the sensitivity of the instruments to differences across different severity groups.

RESULTS

Overall 10,033 respondents (52% female) completed the survey, of which 300 had a respiratory condition. There were moderate to high correlation between bolt-ons with EQ-5D-5L and WHODAS. The EQ-5D-5L + bolt-ons slightly reduced the ceiling effect in comparison to the EQ-5D-5L. The effect size was larger for people with respiratory conditions than people who did not have a respiratory condition.

CONCLUSION

The results show that adding the respiratory bolt-on to the EQ-5D-5L might slightly improve the instruments descriptive sensitivity. The choice of bolt-on may be driven by whether overall problems or limitations are being measured.

A scoping review to create a framework for the steps in developing condition-specific preference-based instruments de novo or from an existing non-preference-based instrument: use of item response theory or Rasch analysis

BACKGROUND

There is no widely accepted framework to guide the development of condition-specific preference-based instruments (CSPBIs) that includes both de novo and from existing non-preference-based instruments. The purpose of this study was to address this gap by reviewing the published literature on CSPBIs, with particular attention to the application of item response theory (IRT) and Rasch analysis in their development.

METHODS

A scoping review of the literature covering the concepts of all phases of CSPBI development and evaluation was performed from MEDLINE, Embase, PsychInfo, CINAHL, and the Cochrane Library, from inception to December 30, 2022.

RESULTS

The titles and abstracts of 1,967 unique references were reviewed. After retrieving and reviewing 154 full-text articles, data were extracted from 109 articles, representing 41 CSPBIs covering 21 diseases or conditions. The development of CSPBIs was conceptualized as a 15-step framework, covering four phases: 1) develop initial questionnaire items (when no suitable non-preference-based instrument exists), 2) establish the dimensional structure, 3) reduce items per dimension, 4) value and model health state utilities. Thirty-nine instruments used a type of Rasch model and two instruments used IRT models in phase 3.

CONCLUSION

We present an expanded framework that outlines the development of CSPBIs, both from existing non-preference-based instruments and de novo when no suitable non-preference-based instrument exists, using IRT and Rasch analysis. For items that fit the Rasch model, developers selected one item per dimension and explored item response level reduction. This framework will guide researchers who are developing or assessing CSPBIs.

Impairment of EQ-5D-5L Domains According to Allergic Rhinitis and Asthma Control: A MASK-air Real-World Study

BACKGROUND

EQ-5D-5L (EuroQOL, 5 Domains, 5 Levels) is a widely used health-related quality-of-life instrument, comprising 5 domains. However, it is not known how each domain is impacted by rhinitis or asthma control.

OBJECTIVE

To assess the association between rhinitis or asthma control and the different EQ-5D-5L domains using data from the MASK-air mHealth app.

METHODS

In this cross-sectional study, we assessed data from all MASK-air users (2015-2021; 24 countries). For the levels of each EQ-5D-5L domain, we assessed rhinitis and asthma visual analog scales (VASs) and the combined symptom-medication score (CSMS). We built ordinal multivariable models assessing the adjusted association between VAS/CSMS values and the levels of each EQ-5D-5L domain. Finally, we compared EQ-5D-5L data from users with rhinitis and self-reported asthma with data from users with rhinitis alone.

RESULTS

We assessed 5354 days from 3092 users. We observed an association between worse control of rhinitis or asthma (higher VASs and CSMS) and worse EQ-5D-5L levels. In multivariable models, all VASs and the CSMS were associated with higher levels of pain/discomfort and daily activities. For anxiety/depression, the association was mostly observed for rhinitis-related tools (VAS nose, VAS global, and CSMS), although the presence of self-reported asthma was also associated with worse anxiety/depression. Worse mobility ("walking around") was particularly associated with VAS asthma and with the presence of asthma.

CONCLUSIONS

A worse rhinitis control and a worse asthma control are associated with higher EQ-5D-5L levels, particularly regarding pain/discomfort and activity impairment. Worse rhinitis control is associated with worse anxiety/depression, and poor asthma control with worse mobility.

Development and validation of an electronic daily control score for asthma (e-DASTHMA): a real-world direct patient data study

BACKGROUND

Validated questionnaires are used to assess asthma control over the past 1-4 weeks from reporting. However, they do not adequately capture asthma control in patients with fluctuating symptoms. Using the Mobile Airways Sentinel Network for airway diseases (MASK-air) app, we developed and validated an electronic daily asthma control score (e-DASTHMA).

METHODS

We used MASK-air data (freely available to users in 27 countries) to develop and assess different daily control scores for asthma. Data-driven control scores were developed based on asthma symptoms reported by a visual analogue scale (VAS) and self-reported asthma medication use. We included the daily monitoring data from all MASK-air users aged 16-90 years (or older than 13 years to 90 years in countries with a lower age of digital consent) who had used the app in at least 3 different calendar months and had reported at least 1 day of asthma medication use. For each score, we assessed construct validity, test-retest reliability, responsiveness, and accuracy. We used VASs on dyspnoea and work disturbance, EQ-5D-VAS, Control of Allergic Rhinitis and Asthma Test (CARAT), CARAT asthma, and Work Productivity and Activity Impairment: Allergy Specific (WPAI:AS) questionnaires as comparators. We performed an internal validation using MASK-air data from Jan 1 to Oct 12, 2022, and an external validation using a cohort of patients with physician-diagnosed asthma (the INSPIRERS cohort) who had had their diagnosis and control (Global Initiative for Asthma [GINA] classification) of asthma ascertained by a physician.

FINDINGS

We studied 135 635 days of MASK-air data from 1662 users from May 21, 2015, to Dec 31, 2021. The scores were strongly correlated with VAS dyspnoea (Spearman correlation coefficient range 0·68-0·82) and moderately correlated with work comparators and quality-of-life-related comparators (for WPAI:AS work, we observed Spearman correlation coefficients of 0·59-0·68). They also displayed high test-retest reliability (intraclass correlation coefficients range 0·79-0·95) and moderate-to-high responsiveness (correlation coefficient range 0·69-0·79; effect size measures range 0·57-0·99 in the comparison with VAS dyspnoea). The best-performing score displayed a strong correlation with the effect of asthma on work and school activities in the INSPIRERS cohort (Spearman correlation coefficients 0·70; 95% CI 0·61-0·78) and good accuracy for the identification of patients with uncontrolled or partly controlled asthma according to GINA (area under the receiver operating curve 0·73; 95% CI 0·68-0·78).

INTERPRETATION

e-DASTHMA is a good tool for the daily assessment of asthma control. This tool can be used as an endpoint in clinical trials as well as in clinical practice to assess fluctuations in asthma control and guide treatment optimisation.

FUNDING

None.

Health-related quality of life decreases in young people with asthma during the transition from adolescence to young adulthood: a birth cohort study

BACKGROUND

During the transition from paediatric to adult healthcare there is a gap between asthma guidelines and actual management with decreased healthcare consultations and dispensations of asthma medications after the transition to adult healthcare among young people with asthma. How health-related quality of life (HRQoL) develops during the transition from adolescence to young adulthood is unclear. Our aim was therefore to investigate HRQoL among young people with asthma during the transition to adulthood. Further, to assess if level of asthma control and physical activity influence any potential association between asthma and HRQoL.

METHODS

The study population consisted of 2268 participants from the ongoing Swedish population-based prospective birth cohort BAMSE (Barn/Child, Allergy, Milieu, Stockholm, Epidemiology). HRQoL was measured using the instrument EQ-5D-3 L and three general questions. The EQ-5D-3 L consists of the EQ-5D descriptive system and the EQ visual analogue scale (EQ VAS). The EQ-5D-3 L instrument and questions on general health, symptoms and treatment of asthma, and lifestyle factors were based on data from follow-ups at 16 and 24 years. Cross-sectional analyses were made.

RESULTS

At the 24-year follow-up, the adjusted median values of EQ VAS were lower compared with at the 16-year follow-up; among both participants with asthma (80 vs. 85, p < 0.01) and those without asthma (80 vs. 87, p < 0.01). At the 24-year follow-up, participants with uncontrolled asthma had a lower adjusted median EQ VAS score than peers with controlled/partly controlled asthma (75 vs. 80, p = 0.03). Further, young adults with asthma who did not fulfil the WHO recommendations on physical activity had lower EQ VAS scores than peers who did (70 vs. 80, p < 0.01).

CONCLUSION

HRQoL is lower in young adulthood than in adolescence. Young adults with asthma having uncontrolled disease or who are physically inactive appear to be particularly vulnerable.

Health-related quality of life in adult patients with asthma according to asthma control and severity: A systematic review and meta-analysis

Background: The utility values are increasingly being used in economic evaluations and health policy decision making. This study aims to conduct a systematic literature review and meta-analysis of the utility values for asthma, particularly with respect to severity and asthma control. Materials and methods: A literature search was conducted using the MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases for studies published until July, 2020, reporting the utilities of adult asthma. We extracted utility values derived by nine indirect and four direct utility instruments. Meta-analyses were performed for each utility instrument according to health states based on the level of asthma control and severity. Results: Fifty-two eligible studies were included in our systematic review, of which forty studies were used in the meta-analyses. Among the 13 utility instruments, the most used was EQ-5D-3L, whereas EQ-5D-5L showed the narrowest 95% confidence interval (95% CI, 0.83-0.86) of pooled utility. The pooled utility of asthma declined with worsening control levels and severity. The pooled utility value of EQ-5D-3L was 0.72 (95% CI, 0.63-0.80) for uncontrolled, 0.82 (95% CI, 0.75-0.88) for partly controlled, and 0.87 (95% CI, 0.84-0.90) for well-controlled asthma. Conclusion: Our study shows that EQ-5D-3L and EQ-5D-5L are appropriate for economic evaluations in terms of availability and variability of information, respectively. Asthma patients had poorer utility values with worsened severity and level of asthma control. This study will be useful for health economists conducting economic evaluations of asthma treatments.

Performance of the EQ-5D-5L Plus Respiratory Bolt-On in the Birmingham Chronic Obstructive Pulmonary Disease Cohort Study

OBJECTIVES

A respiratory bolt-on dimension for the EQ-5D-5L has recently been developed and valued by the general public. This study aimed to validate the EQ-5D-5L plus respiratory dimension (EQ-5D-5L+R) in a large group of patients with chronic obstructive pulmonary disease (COPD).

METHODS

Validation was undertaken with data from the Birmingham COPD Cohort Study, a longitudinal UK study of COPD primary care patients. Data on the EQ-5D-5L+R were collected from 1008 responding participants during a follow-up questionnaire in 2017 and combined with (previously collected) data on patient and disease characteristics. Descriptive and correlation analyses were performed on the EQ-5D-5L+R dimensions and utilities, in relation to COPD characteristics and compared with the EQ-5D-5L without respiratory dimension. Multivariate regression models were estimated to test whether regression coefficients of clinical characteristics differed between the EQ-5D-5L+R utility and the EQ-5D-5L utility.

RESULTS

Correlation coefficients for the EQ-5D-5L+R utility with COPD parameters were slightly higher than the EQ-5D-5L utility. Both instruments displayed discriminant validity but analyses in clinical subgroups of patients showed larger absolute differences in utilities for the EQ-5D-5L+R. In the multivariate analyses, only the coefficient for the COPD Assessment Test score was higher for the model using the EQ-5D-5L+R utility as outcome.

CONCLUSIONS

This study showed that the addition of a respiratory domain to the EQ-5D-5L led to small improvements in the instrument's performance. Comparability of the EQ-5D across diseases, currently considered one of its strengths, would have to be traded off against a modest improvement in utility difference when adding the respiratory dimension.

Cost-Effectiveness of Pulmonary Rehabilitation in Patients With Bronchial Asthma: An Analysis of the EPRA Randomized Controlled Trial

OBJECTIVES

At 3 months after the intervention, this study evaluates the cost-effectiveness of a 3-week inpatient pulmonary rehabilitation (PR) in patients with asthma compared with usual care alongside the single-center randomized controlled trial-Effectiveness of Pulmonary Rehabilitation in Patients With Asthma.

METHODS

Adopting a societal perspective, direct medical costs and productivity loss were assessed using the Questionnaire for Health-Related Resource Use-Lung, a modification of the FIM in an Elderly Population. The effect side was operationalized as minimal important differences (MIDs) of the Asthma Control Test (ACT) and the Asthma Quality of Life Questionnaire (AQLQ) and through quality-adjusted life-years (QALYs) gained. Adjusted mean differences in costs (gamma-distributed model) and each effect parameter (Gaussian-distributed model) were simultaneously calculated within 1000 bootstrap replications to determine incremental cost-effectiveness ratios (ICERs) and to subsequently delineate cost-effectiveness acceptability curves.

RESULTS

PR caused mean costs per capita of €3544. Three months after PR, we observed higher mean costs (Δ€3673; 95% confidence interval (CI) €2854-€4783) and improved mean effects (ACT Δ1.59 MIDs, 95% CI 1.37-1.81; AQLQ Δ1.76 MIDs, 95% CI 1.46-2.08; QALYs gained Δ0.01, 95% CI 0.01-0.02) in the intervention group. The ICER was €2278 (95% CI €1653-€3181) per ACT-MID, €1983 (95% CI €1430-€2830) per AQLQ-MID, and €312 401 (95% CI €209 206-€504 562) per QALY gained.

CONCLUSIONS

Contrasting of PR expenditures with ICERs suggests that the intervention, which achieves clinically relevant changes in asthma-relevant parameters, has a high probability to be already cost-effective in the short term. However, in terms of QALYs, extended follow-up periods are likely required to comprehensively judge the added value of a one-time initial investment in PR.

Do Drug Accessibility and OOP Burden Affect Health-Related Quality of Life of Patients With Chronic Diseases? - EQ-5D-5L Evaluation Evidence From Five Districts in China

Purpose: The dependence of patients with chronic diseases on drugs may affect their health-related quality of life (HRQoL). This study aims to assess the relationship between the direct economic burden caused by out-of-pocket (OOP) payments, drug accessibility, sociodemographic characteristics, and health-related quality of life. Methods: 1,055 patients with chronic diseases from Gansu, Hebei, Sichuan, Zhejiang, and Tianjin were investigated. Data collection included basic conditions and economic and health insurance conditions of patients with chronic diseases. The CLAD and Tobit regression models were used to analyze and compare the health-related quality of life and influencing factors of patients with chronic diseases in five districts. Differentiated analysis was conducted through sub-sample regression to explore the variable health effects of patients with single and multiple diseases. Results: A total of 1,055 patients with chronic diseases participated in the study, 54.4% of whom were women. The overall average utility score was 0.727, of which Sichuan Province was the highest with 0.751. Participants reported the highest proportion of pain/discomfort problems, while patients reported the least problems with self-care. The improvement of drug accessibility and the reduction of the burden of out-of-pocket expenses have significant positive effects on HRQoL. Various sociodemographic factors such as age and gender also have significant impact on HRQoL of patients with chronic diseases. HRQoL of patients with multiple chronic diseases is more affected by various influencing factors than that of patients with single disease. Conclusion: In order to improve the quality of life of patients with chronic diseases, it is of great importance to ensure the accessibility of drugs and reduce patients' medication burden. Future focus should shift from preventing and controlling chronic diseases as individual diseases to meeting the comprehensive health needs of people suffering from multiple diseases.

Relationship between health-related quality of life and subjective wellbeing in asthma

OBJECTIVE

Poor health-related quality of life (HRQoL) is associated with a high risk of acute exacerbations in patients with asthma. The use of health state utility instruments to measure HRQoL is common, but it has been criticised for failing to adequately capture the impact of the condition from the patient perspective. We aimed to assess the ability of subjective wellbeing and health state utility instruments to capture important HRQoL dimensions for asthma patients.

METHODS

Regression analyses were conducted using data (n = 856 asthma patients) from a large multi-national cross-sectional survey to explore the relationship between subjective wellbeing (ONS4, PWI, SWLS), health state utility (15D, AQoL-8D, EQ-5D-5L, HUI3, SF-6D, SF-6Dv2), and an asthma-specific instrument (AQLQ-S). The latent structure of different instruments was investigated using an exploratory factor analysis.

RESULTS

All instruments could distinguish the impact of asthma on HRQoL. Among health utility instruments, 15D, SF-6D and AQoL-8D were more sensitive based on the average standardised regression coefficients. AQOL-8D had the strongest correlation with subjective wellbeing. Nevertheless, the exploratory factor analysis showed a complementary relationship between subjective wellbeing and HRQoL instruments. The most important subjective wellbeing domains were standard of living, achieving in life, and personal relationships; although contributions of these domains to overall life satisfaction differed among asthma patients identified by a latent class analysis.

CONCLUSION

The use of subjective wellbeing alongside AQLQ-S and health state utility instruments provides a comprehensive approach to assess the impact of asthma on the patient's life. Further research is needed to incorporate these measures in health care evaluation.

Psychometric Validation of the EQ-5D-3L in Patients with Nontuberculous Mycobacterial (NTM) Lung Disease Caused by Mycobacterium avium Complex (MAC)

PURPOSE

This analysis evaluated the psychometric properties of the EQ-5D-3L among patients with Mycobacterium avium complex lung disease (MAC-LD).

METHODS

Data from the Phase III CONVERT trial were analyzed. Study measures including the EQ-5D-3L, St. George's Respiratory Questionnaire (SGRQ), the 6-minute walk test (6MWT), and percent predicted forced expiratory volume in 1 second (ppFEV1) were collected at baseline, month 3 (M3), month 4 (M4; only 6MWT), and month 6 (M6). Item characteristics and validity were evaluated at baseline. Test-retest reliability was assessed using intraclass correlation coefficients (ICC) and a weighted kappa statistic among a subgroup of stable patients. Validity was tested by evaluating correlations of the EQ-5D-3L index/visual analogue scale (VAS) scores with SGRQ and 6MWT and comparing mean index/VAS scores across known groups defined using 6MWT and ppFEV1. Responsiveness of the EQ-5D-3L was assessed using 6MWT, SGRQ, ppFEV1, and culture conversion as anchors.

RESULTS

The index score was subject to ceiling effects, with 32.6% of patients reporting perfect health at baseline. ICCs for the index (0.80) and VAS (0.85) scores and weighted kappas for the domains (0.5-0.72) indicated adequate test-retest reliability. Correlations between the index/VAS scores and related domains of the SGRQ and 6MWT were as hypothesized (0.31-0.62), and the mean index/VAS scores were significantly different between the 6MWT and ppFEV1 known groups (p<0.05), supporting the validity of the EQ-5D-3L. No evidence was found supporting the responsiveness of the EQ-5D-3L to changes in any of the anchors.

CONCLUSION

EQ-5D-3L exhibited evidence of validity and reliability but poor responsiveness to clinically meaningful changes in patients with MAC-LD.

How does the EQ-5D-5L perform in asthma patients compared with an asthma-specific quality of life questionnaire?

Background

Asthma patients experience impairments in health-related quality of life (HRQL). Interventions are available to improve HRQL. EQ-5D-5L is a common generic tool used to evaluate health interventions. However, there is debate over whether the use of this measure is adequate in asthma patients.

Methods

We used data from 371 asthma patients participating in a pulmonary rehabilitation (PR) program from the EPRA randomized controlled trial. We used four time points: T0 randomization, T1 start PR, T2 end PR, T3 3 months follow-up. We calculated floor and ceiling effects, intra-class correlation (ICC), Cohen’s d, and regression analysis to measure the sensitivity to changes of EQ-5D-5 L (EQ-5D index and Visual Analog Scale (VAS)) and the disease-specific Asthma Quality of Life Questionnaire (AQLQ). Furthermore, we estimated the minimally important difference (MID). Based on the Asthma Control Test (ACT) scores, we defined three groups: 1. ACT-A (ACT> 19) controlled asthma, 2. ACT-B (14 < ACT≤19) not well-controlled asthma, and 3. ACT-C (ACT≤14) very poorly controlled asthma.

Results

Only the EQ-5D index showed ceiling effects at T2 and T3 (32%). ICC (between T0 and T1) was moderate or good for all measures. Cohen’s d at T2 and T3 was better at differentiating between ACT-A and ACT-B than between ACT-B and ACT-C. The EQ-5D index showed moderate effect sizes (0.63–0.75), while AQLQ showed large effect sizes (0.74–1,48). VAS was responsive to pronounced positive and negative ACT changes in every period, and AQLQ mostly to the positive changes, whereas the EQ-5D index was less responsive. We estimated a MID of 0.08 for the EQ-5D index, 12.3 for VAS, and 0.65 for AQLQ.

Conclusion

All presented HRQL tools had good discriminatory power and good reliability. However, EQ-5D-5 L did not react very sensitively to small changes in asthma control. Therefore, we would suggest using supplementary measures in addition to EQ-5D-5 L to evaluate asthma-specific interventions more comprehensively.

Trial registration

German Clinical Trial Register, DRKS00007740 (date of registration: 05/15/2015), https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00007740. The registration took place prospectively.

Cost-effectiveness of omalizumab for the treatment of moderate-to-severe uncontrolled allergic asthma in the United States

Objective: Uncontrolled asthma is associated with considerable clinical burden and costs to payers and patients. US economic models evaluating biologics using data from clinical trials demonstrate high incremental cost-effectiveness ratios (ICERs), but the cost-effectiveness based on real-world treatment patterns is unknown. This analysis used real-world evidence to assess the cost-effectiveness of adding omalizumab to standard of care (SOC).Methods: A Markov model was applied to track patients' health states in 2-week cycles, comparing costs and treatment effects of SOC alone versus SOC + omalizumab over a lifetime (US payer perspective). Outcomes included exacerbation events, life years, quality-adjusted life years (QALYs), total costs, and an ICER. Patient characteristics, exacerbations, patient-reported outcomes, and work productivity were derived from the real-world PROSPERO (Prospective Study to Evaluate Predictors of Clinical Effectiveness in Response to Omalizumab) study. Published literature informed mortality, exacerbation-related disutility, and unit costs. Sensitivity analyses assessed model robustness.Results: Over a lifetime horizon, omalizumab was associated with an increase of 2.0 QALYs at a cost of $US 148,319 in patients with uncontrolled asthma (ICER of $75,319/QALY gained) and a reduction in exacerbations of 6.0 events/patient. Accounting for responder status improved the ICER ($70,505/QALY); incorporating indirect costs further reduced the ICER. One-way and multivariate sensitivity analyses confirmed that the base case outcome was robust to variation in inputs.Conclusions: Based on real-world outcomes, omalizumab may be cost-effective for uncontrolled asthma from the US payer perspective. Including broader evidence on treatment discontinuation, caregiver burden, and oral corticosteroid reduction from real-world studies may better reflect the effects and value of omalizumab for all healthcare stakeholders.

Impact of allergies on health-related quality of life in patients with asthma

Objective: To estimate the health-related quality of life (HRQoL) and health utilities among asthma patients with and without comorbid allergies in a managed care population.Methods: This was a retrospective analysis of patient survey responses and pharmacy claims from the Observational Study of Asthma Control and Outcomes (OSACO). Patients ≥12 years-old with persistent asthma received four identical surveys between April-2011 and December-2012. The presence of allergy was identified by a positive response to a survey question about hay fever/seasonal allergies and ≥1 diagnosis-related ICD-9-CM code(s) for allergic conditions. HRQoL instruments included generic utility (EQ-5D-3L [including VAS]), asthma-specific utility (AQL-5D) and asthma-specific health status (Mini Asthma Quality of Life Questionnaire [MiniAQLQ]). Median regression was used for utility scores and Least Squares regression for MiniAQLQ, adjusting for sociodemographic characteristics and smoking.Results: Of the 2681 asthmatics who completed the first survey in the OSACO study, 971 had comorbid allergies. After adjusting for covariates, asthma patients with comorbid allergies had significantly lower MiniAQLQ scores than patients without allergies (-0.489 [95% CI -0.570, -0.409]; p < 0.01), with the greatest decrement/impairment observed for the environmental stimuli domain (-0.729 [95% CI -0.844, -0.613]; p < 0.01). Utility scores were also statistically significantly lower for asthma patients with comorbid allergies compared to those without allergies (EQ-5D, -0.031 [95% CI -0.047, -0.015]; AQL-5D, -0.036 [95% CI -0.042, -0.029]; p < 0.01 each).Conclusions: The presence of allergies with persistent asthma is associated with a significant deleterious impact on several different measures of HRQoL.

Exploring the Impact of Adding a Respiratory Dimension to the EQ-5D-5L

Objectives. To evaluate the impact of adding a respiratory dimension (a bolt-on dimension) to the EQ-5D-5L health state valuations. Methods. Based on extensive regression and principal component analyses, 2 respiratory bolt-on candidates were formulated: R1, limitations in physical activities due to shortness of breath, and R2, breathing problems. Valuation interviews for the selected bolt-ons were performed with a representative sample from the Dutch general public using the standardized interview protocol and software of the EuroQol group. Hybrid models based on the combined time-tradeoff (TTO) and discrete choice experiment (DCE) data were estimated to assess whether the 5 levels of the respiratory bolt-on led to significant changes in utility values. Results. For each bolt-on candidate, slightly more than 200 valuation interviews were conducted. Mean TTO values and DCE choice probabilities for health states with a level 4 or 5 for the respiratory dimension were significantly lower compared with the same health states in the Dutch EQ-5D-5L valuation study without the respiratory dimension. Results of hybrid models showed that for the bolt-on “limitations in physical activities,” the utility decrements were significant for level 3 (–0.055), level 4 (–0.087), and level 5 (–0.135). For “breathing problems,” the utility decrements for the same levels were greater (–0.086, –0.219, and –0.327, respectively). Conclusions. The addition of each of the 2 respiratory bolt-ons to the EQ-5D-5L had a significant effect on the valuation of health states with severe levels for the bolt-on. The bolt-on dimension “breathing problems” showed the greatest utility decrements and therefore seems the most appropriate respiratory bolt-on dimension.

Is the EQ-5D fit for purpose in asthma? Acceptability and content validity from the patient perspective

Background

The increasing emphasis on patient-reported outcomes in health care decision making has prompted greater rigor in the evidence to support the instruments used. Acceptability and content validity are important properties of any measure to ensure it assesses the relevant aspects of the target concept. The purpose of this study was to evaluate the acceptability and content validity of the EQ-5D 5-Level (EQ-5D-5L) to assess the impact of asthma on patients’ lives.

Methods

Qualitative interviews were conducted with 40 adults with asthma in the United Kingdom. The first 25 interviews used cognitive-debriefing methods to assess the relevance and acceptability of the EQ-5D-5L and two asthma-specific measures for comparison: an asthma-specific, preference-based measure (the Asthma Quality of Life Utility Index–5 Dimensions) and an Asthma Symptom Diary. The final 15 interviews combined concept elicitation to identify patient-perceived asthma impact, and cognitive debriefing to assess relevance and acceptability of the EQ-5D-5L and the Asthma Symptom Diary. Cognitive-debriefing feedback on the content of the measures was collated and summarized descriptively. The concept-elicitation data were analyzed thematically.

Results

Participants were aged 20 to 57 years and 62.5% were female. Although some participants expressed positive opinions on aspects of the EQ-5D-5L, only the usual activities dimension was consistently considered relevant to participants’ asthma experiences. The mobility and self-care dimensions prompted strong negative reactions from some participants. Variations in interpretation of the mobility dimension and difficulties with multiple concepts in the pain/discomfort and anxiety/depression dimensions also were noted. Concepts reported by participants as missing included environmental triggers, asthma symptoms, emotions, and sleep. The EQ-5D-5L was the least preferred measure to describe the impact of asthma on participants’ lives. Participants reported shortness of breath and impact on activities as especially salient issues.

Conclusions

The content of the EQ-5D-5L was poorly aligned with the patient-perceived impact of asthma, and the measure failed to meet basic standards for acceptability and content validity as a measure to assess the impact of asthma from the patient perspective. The shortcomings identified raise concerns regarding the appropriateness of the EQ-5D in asthma and further evaluation is warranted.

Are condition-specific utilities more valid than generic preference-based ones in asthma? Evidence from a study comparing EQ-5D-3L and SF-6D with AQL-5D

BACKGROUND

Systematic discrepancies have been shown in utility values derived from different instruments. This study compares utilities from the condition-specific AQL-5D and the generic EQ-5D-3L and SF-6D in an asthmatic population with heterogeneous health-related quality of life (HRQoL), disease severity, and control status.

METHODS

A consecutive sample of 104 patients diagnosed with asthma completed a survey containing the Greek versions of SF-36, EQ-5D-3L, and AQLQ(s). Treatment adequacy was assessed with the Asthma Control Questionnaire (ACQ), and asthma severity according to Global Initiative for Asthma 2016 guidelines. Association and agreement between instruments were assessed with Spearman's correlation and Bland-Altman plots.

RESULTS

AQL-5D utilities exceeded (p < 0.001) those from EQ-5D-3L and SF-6D. There were weak-to-moderate correlations (<0.5) between most dimensions of AQL-5D, and those of EQ-5D-3L and SF-6D, and strong correlations between similar dimensions of EQ-5D-3L and SF-6D. Significant differences (p < 0.001) were observed throughout the visual analog scale (VAS), asthma severity and asthma control subgroups, with AQL-5D consistently higher than EQ-5D-3L and SF-6D.

CONCLUSIONS

All instruments distinguished between differing degrees of asthma control, but only AQL-5D discriminated between asthma severity and HRQoL as well. Although the relatively small sample warrants caution in interpreting the subgroup results, this study contributes to the growing number of comparisons between condition-specific and generic preference-based instruments.

The Allergic Rhinitis and its Impact on Asthma (ARIA) score of allergic rhinitis using mobile technology correlates with quality of life: The MASK study

Mobile technology has been used to appraise allergic rhinitis control, but more data are needed. To better assess the importance of mobile technologies in rhinitis control, the ARIA (Allergic Rhinitis and its Impact on Asthma) score ranging from 0 to 4 of the Allergy Diary was compared with EQ-5D (EuroQuol) and WPAI-AS (Work Productivity and Activity Impairment in allergy) in 1288 users in 18 countries. This study showed that quality-of-life data (EQ-5D visual analogue scale and WPA-IS Question 9) are similar in users without rhinitis and in those with mild rhinitis (scores 0-2). Users with a score of 3 or 4 had a significant impairment in quality-of-life questionnaires.

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.

Assessing the value of mepolizumab for severe eosinophilic asthma: a cost-effectiveness analysis

BACKGROUND

Adding mepolizumab to standard treatment with inhaled corticosteroids and controller medications could decrease asthma exacerbations and use of long-term oral steroids in patients with severe disease and increased eosinophils; however, mepolizumab is costly and its cost effectiveness is unknown.

OBJECTIVE

To estimate the cost effectiveness of mepolizumab.

METHODS

A Markov model was used to determine the incremental cost per quality-adjusted life year (QALY) gained for mepolizumab plus standard of care (SoC) and for SoC alone. The population, adults with severe eosinophilic asthma, was modeled for a lifetime time horizon. A responder scenario analysis was conducted to determine the cost effectiveness for a cohort able to achieve and maintain asthma control.

RESULTS

Over a lifetime treatment horizon, 23.96 exacerbations were averted per patient receiving mepolizumab plus SoC. Avoidance of exacerbations and decrease in long-term oral steroid use resulted in more than $18,000 in cost offsets among those receiving mepolizumab, but treatment costs increased by more than $600,000. Treatment with mepolizumab plus SoC vs SoC alone resulted in a cost-effectiveness estimate of $386,000 per QALY. To achieve cost effectiveness of approximately $150,000 per QALY, mepolizumab would require a more than 60% price discount. At current pricing, treating a responder cohort yielded cost-effectiveness estimates near $160,000 per QALY.

CONCLUSION

The estimated cost effectiveness of mepolizumab exceeds value thresholds. Achieving these thresholds would require significant discounts from the current list price. Alternatively, treatment limited to responders improves the cost effectiveness toward, but remains still slightly above, these thresholds. Payers interested in improving the efficiency of health care resources should consider negotiations of the mepolizumab price and ways to predict and assess the response to mepolizumab.