Comparing Generic and Condition-Specific Preference-Based Measures in Epilepsy: EQ-5D-3L and NEWQOL-6D

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.

Mapping IWQOL-Lite onto EQ-5D-5L and SF-6Dv2 among overweight and obese population in China

PURPOSE

To develop the mapping functions from the Impact of Weight on Quality of Life-Lite (IWQOL-Lite) scores onto the EQ-5D-5L and SF-6Dv2 utility values among the overweight and obese population in China.

METHODS

A representative sample of the overweight and obese population in China stratified by age, sex, body mass index (BMI), and area of residence was collected by online survey and the sample was randomly divided into development (80%) and validation (20%) datasets. The conceptual overlap between the IWQOL-Lite and the EQ-5D-5L or SF-6Dv2 was evaluated by Spearman's correlation coefficients. Five models, including OLS, Tobit, CLAD, GLM, and PTM were explored to derive mapping functions using the development dataset. The model performance was assessed using MAE, RMSE, and the percentage of AE > 0.05 and AE > 0.1 in the validation dataset.

RESULTS

A total of 1000 respondents (48% female; mean [SD] age: 51.7 [15.3]; mean [SD] BMI: 27.4 [2.8]) were included in this study. The mean IWQOL-Lite scores and the utility values of EQ-5D-5L and SF-6Dv2 were 78.5, 0.851, and 0.734, respectively. The best-performing models predicting EQ-5D-5L and SF-6Dv2 utilities both used IWQOL-Lite total score as a predictor in the CLAD model (MAE: 0.083 and 0.076 for the EQ-5D-5L and SF-6Dv2; RMSE: 0.125 and 0.103 for the EQ-5D-5L and SF-6Dv2; AE > 0.05: 20.5% and 27.5% for the EQ-5D-5L and SF-6Dv2; AE > 0.10: 9.5% and 15.0% for the EQ-5D-5L and SF-6Dv2).

CONCLUSION

CLAD models with the IWQOL-Lite total score can be used to predict both the EQ-5D-5L and SF-6Dv2 utility values among overweight and obese population in China.

Favorable combinations of antiseizure medication with vagus nerve stimulation to improve health-related quality of life in patients with epilepsy

BACKGROUND

Vagus nerve stimulation (VNS) is a non-pharmacological treatment of refractory epilepsy, which also has an antidepressive effect. The favorable combinations of VNS with specific mechanisms of action of antiseizure medication (ASM) on mood and health-related quality of life (HrQol) have not yet been studied. The objective was to identify favourable combinations of specific ASMs with VNS for the HrQoL and depression in refractory epilepsy.

METHODS

We performed an observational study including patients with refractory epilepsy and an implanted VNS (N = 151). In the first 24 months after VNS implantation, all patients were on stable ASM therapy. We used the standardized questionnaires QOLIE10, EQVAS and EQ5D to evaluate HrQoL as well as the Beck Depression Inventory (BDI). Multiple regression analysis was performed to evaluate the synergistic combinations of ASM with VNS for HrQoL.

RESULTS

At the year-two follow-up (N = 151, age 45.2 ± 17.0 years), significant improvement (p < 0.05) in BDI scores was found for combination of VNS with SV2A modulators (58.4 %) or AMPA antagonists (44.4 %). A significant increase of HrQoL by at least 30 % (p < 0.05) was measured for a combination of VNS with SV2A modulators (brivaracetam, levetiracetam) or slow sodium channel inhibitors (eslicarbazepine, lacosamide).

CONCLUSION

The results of our study suggests a favorable effect of the combination of SV2A modulators or slow sodium channel inhibitors with VNS on the HrQoL in comparison to other ASMs. Besides the possible synergistic effects on the seizure frequency, the amelioration of behavioral side effects of SV2A modulators by VNS is an important factor of HrQoL-improvement in these combinations.

Early cost-utility analysis of genetically guided therapy for patients with drug-resistant epilepsy

OBJECTIVE

Existing gene panels were developed to understand the etiology of epilepsy, and further benefits will arise from an effective pharmacogenomics panel for personalizing therapy and achieving seizure control. Our study assessed the cost-effectiveness of a pharmacogenomics panel for patients with drug-resistant epilepsy, compared with usual care.

METHODS

A cost-utility analysis was employed using a discrete event simulation model. The microsimulation model aggregated the costs and benefits of genetically guided treatment versus usual care for 5000 simulated patients. The 10-year model combined data from various sources including genomic databases on prevalence of variants, population-level pharmaceutical claims on antiseizure medications, published long-term therapy retention rates, patient-level cost data, and systematic reviews. Incremental cost per quality-adjusted life-year (QALY) gained was computed. Deterministic and probabilistic sensitivity analyses were undertaken to address uncertainty in model parameters.

RESULTS

The mean cost of the genetically guided treatment option was AU$98 199 compared with AU$95 386 for usual care. Corresponding mean QALYs were 4.67 compared with 4.28 for genetically guided and usual care strategies, respectively. The incremental cost per QALY gained was AU$7381. In probabilistic sensitivity analyses, the incremental cost per QALY gained was AU$6321 (95% uncertainty interval = AU$3604-AU$9621), with a 100% likelihood of being cost-effective in the Australian health care system. The most influential drivers of the findings were the monthly health care costs associated with reduced seizures, costs when seizures continued, and the quality-of-life estimates under genetically guided and usual care strategies.

SIGNIFICANCE

This early economic evaluation of a pharmacogenomics panel to guide treatment for drug-resistant epilepsy could potentially be cost-effective in the Australian health care system. Clinical trial evidence is necessary to confirm these findings.

EuroQOL-5D-3L does not adequately map quality-of-life deterioration in severely affected patients with epilepsy

INTRODUCTION

The steadily increasing impact of health-related quality of life (HRQOL) on reasonable diagnostic and therapeutic decisions makes the correct mapping of HRQOL indispensable in modern epileptology. The aim of this study was to address the reliability of the often-used generic HRQOL screening questionnaire EuroQOL 5-dimension, 3-level (EQ-5D-3L) by comparing its normalized index value (calculated via the time trade-off method) and visual analog scale (VAS) to the gold standard of the extensive Quality of Life in Epilepsy Inventory (QOLIE-31). QOLIE-10 scores were compared with the extensive QOLIE-31 and EQ-5D-3L TTO.

METHODS

We conducted a retrospective analysis of a monocentric study of 184 patients with epilepsy. Bivariate Spearman correlation analysis and Fisher's r-to-z transformation were used to compare the strengths of correlations of EQ-5D-3L, QOLIE-10 and QOLIE-31 with different epilepsy-specific domains (disease severity, drug interactions, emotional well-being, stigmatization, seizure-related anxiety, cognitive impairment).

RESULTS

The different metrics of EQ-5D-3L, QOLIE-10 and QOLIE-31 showed moderate to very strong intra- and inter-metric correlations for overall HRQOL. Quality of Life in Epilepsy Inventory-31 VAS and EQ-5D-3L VAS did not show any significantly different strengths of correlations with respect to the domains studied. In contrast, the correlation strength of the normalized EQ-5D-3L index value differed significantly from the QOLIE-31 T-score for several domains, for example, for drug-related adverse events, neuropsychological deficits, symptoms of depression and seizure worry. In seizure-free patients, EQ-5D-3L VAS and EQ-5D-3L index values correlated significantly less with the domain of "cognitive impairment" than the QOLIE-31 T-score. In patients without relevant neuropsychological deficits, the strengths of correlations with the assessed domains did not differ significantly between EQ-5D-3L metrics and the QOLIE-31 T-score. The HRQOL mapping probability of QOLIE-10 was inferior to QOLIE-31 and comparable to EQ-5D-3L regarding the analyzed domains.

CONCLUSION

In contrast to the EQ-5D-3L VAS, EQ-5D-3L index values do not adequately map health-related quality of life in severely affected patients with epilepsy and therefore should not be used as screening tools. The QOLIE-31 T-score remains the gold standard for HRQOL assessment in patients with epilepsy.

The use of patient-reported measures in epilepsy care: the Calgary Comprehensive Epilepsy Program experience

The regular use of patient-reported measures (PRMs) has been associated with greater patient satisfaction and outcomes. In this article, we will review the Calgary Comprehensive Epilepsy Program's successful experience with PRMs in both clinical and research settings, as well as our current challenges and future directions. Our experience will illustrate that is feasible and convenient to implement PRMs, and especially electronic PRMs (ePRMs), into epilepsy clinics. These PRMs have direct clinical and research applications. They inform clinical decision making through readily interpretable scales to which clinicians can expeditiously respond. Equally, they are increasingly forming an integral and central component of intervention and outcomes-based research. However, implementation studies are necessary to address knowledge gaps and facilitate adoption and dissemination of this approach. A natural symbiosis of the clinical and research realms is precision medicine. The foundations of precision-based interventions are now being set whereby we can maximize the quality of life and psychosocial functioning on an individual level. As illustrated in this article, this exciting prospect crucially depends on the routine use of ePRMs in the everyday care of people with epilepsy. Increasing ePRMs uptake will clearly be a catalyst propelling precision epilepsy from aspiration to clinical reality.

Assessment of Quality of Life 8-Dimension (AQoL-8D): translation, validation, and application in two Dutch trials in patients with epilepsy and schizophrenia

BACKGROUND

To translate and linguistically validate the Assessment of Quality of Life 8-dimensions (AQoL-8D) for use in the Netherlands and to compare the psychometric properties of AQoL-8D with the EuroQol 5-dimensions 5-levels (EQ-5D-5L) in two patient samples.

METHODS

AQoL-8D was translated from English into Dutch. The translated AQoL-8D was then administered alongside the EQ-5D-5L at baseline and follow-up of two Dutch randomized controlled trials among patients with epilepsy and schizophrenia. These data were subjected to a post-hoc analysis assessing the psychometric properties of AQol-8D vis-à-vis EQ-5D-5L in terms of known-groups construct validity, responsiveness, and floor/ceiling effects.

RESULTS

In total, 103 epilepsy patients and 99 schizophrenia patients were included in this study. In both datasets, the two instruments discriminated between known-groups, but in schizophrenia, AQoL-8D showed higher responsiveness than EQ-5D-5L, while both instruments showed equal responsiveness in epilepsy. Ceiling effects were only found for EQ-5D-5L in both epilepsy (26.6%) and schizophrenia (6.1%).

CONCLUSION

Our results have shown that, among other things, AQoL-8D presents better ability to discriminate between known-groups and shows no ceiling effect. Based on our results, we would recommend the use of AQoL-8D in addition to EQ-5D-5L in trials assessing patient's quality of life in patients with epilepsy or schizophrenia.

The estimation of a preference-based single index for the IBS-QoL by mapping to the EQ-5D-5L in patients with irritable bowel syndrome

Purpose

The Irritable Bowel Syndrome Quality of Life (IBS-QoL) questionnaire is a commonly used and validated IBS-specific QoL instrument. However, this questionnaire is in contrast to the EQ-5D-5L, not preference-based and as such does not allow calculation of QALYs. The objective of this study was to describe the convergent- and known-group validity of both questionnaires and to develop a mapping algorithm from EQ-5D-5L which enable IBS-QoL scores to be transformed into utility scores for use in economic evaluations.

Methods

We used data from two multicenter randomized clinical trials, which represented the estimation and external validation dataset. The convergent validity was investigated by examining correlations between the EQ-5D-5L and IBS-QoL and the known-group validity by calculating effect sizes. Ordinary least squares (OLS), censored least absolute deviations (CLAD), and mixture models were used in this mapping approach.

Results

283 IBS patients were included (n = 189 vs. n = 84). Mean IBS-QoL score was 71.13 (SD 15.66) and mean EQ-5D-5L utility score was 0.73 (SD 0.19). The overall sensitivity of the IBS-QoL and EQ-5D-5L to discriminate between patient and disease characteristics was similar. CLAD model 4, containing the total IBS-QoL score and squared IBS-SSS (IBS severity scoring system), was chosen as the most appropriate model to transform IBS-QoL scores into EQ-5D-5L utility scores.

Conclusion

This study reports the development of an algorithm where the condition-specific questionnaire IBS-QoL can be used to calculate utility values for use in economic evaluations. Including a clinical measure, IBS-SSS, in the model improved the performance of the algorithm.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11136-021-02995-y.

Health related quality of life in adults with asthma: a systematic review to identify the values of EQ-5D-5L instrument

INTRODUCTION

The EQ-5D is the most popular generic preference-based instrument used for asthma patients. This study aims to explore the psychometric properties of the EQ-5D-5L instrument in patients with asthma and identify the EQ-5D-5L scores in these patients.

METHOD

PubMed, Scopus, Web of Science, Google Scholar and CEA Registry were searched with English language from 2009 until April 2020. Retrieved studies were checked against the inclusion criteria. Reference lists of the included articles were also reviewed. The quality of included articles was evaluated using Mitton checklist and the data were extracted by a reviewer and were checked by a second reviewer. Meta-analysis was done to calculate the overall scores based on type of asthma control.

RESULTS

A total of 17 articles were included. The EQ-5D-5L scores ranged from 0.45 to 0.93 and the VAS scores ranged from 35.67 to 83.80. The EQ-5D-5L is higher in well-controlled (0.88, 95% CI: 0.81-0.96, P = 0.0001) than partly controlled (0.80, 95% CI: 0.74-0.85, P = 0.001) and poorly controlled asthma (0.72, 95% CI: 0.67-0.77, P = 0.01). Validity in two studies was weak and, in other studies, it was moderate to strong. Responsiveness of the EQ-5D-5L, that was shown in a study, was less than other generic instruments, and reliability was adequate in only study that had been reported. Ceiling effects were between 8.30% to 35%.

CONCLUSION

Higher score of the EQ-5D-5L was consistent with well-controlled asthma patients and those with lower severity of asthma. The assessment of psychometric properties of the EQ-5D-5L needs further observations.

Comparing multi-attribute utility instruments: CP-6D, a Cerebral palsy specific instrument, vs AQoL-4D

Background: Economic-evaluations of Cerebral palsy (CP) were based on utility estimates of health-related quality of life (HRQoL) from generic multi-attribute utility instruments (MAUIs). However, generic instruments had limited use as they could not capture some of the important aspects of living with CP. The Cerebral palsy 6 Dimension (CP-6D) is a disease specific MAUI. In this study, we compared the results of CP-6D with the Assessment of Quality of Life (AQoL-4D), a generic MAUI, and tested the criterion validity of the CP-6D in the general population.Methods:An online survey of the Australian general population (n = 2002), who completed both the AQoL-4D and CP-6D MAUIs, was conducted. Validity was assessed from the correlations between the domains, items and instruments. ANOVA and t-tests were used to assess the instrument's discrimination in different social demographic categories.Results:There was a moderate correlation between the instruments (0.64). Differences in socio-demographic characteristics showed a medium effect size (p < 0.001) in both instruments and had a similar effect on utility weights in both instruments. Although the CP-6D was more sensitive to changes in income and education.Conclusions: Our results suggest that CP-6D and AQoL-4D were measuring a similar underlying construct. Both instruments responded similarly to socio-demographic differences.

An economic evaluation of vagus nerve stimulation as an adjunctive treatment to anti-seizure medications for the treatment of drug-resistant epilepsy in England

INTRODUCTION

Anti-seizure medications (ASMs) are commonly used to prevent recurring epileptic seizures, but around a third of people with epilepsy fail to achieve an adequate response. Vagus nerve stimulation (VNS) is clinically recommended for people with drug-resistant epilepsy (DRE) who are not suitable for surgery, but the cost-effectiveness of the intervention has not recently been evaluated. The study objective is to estimate costs and quality-adjusted life-years (QALYs) associated with using VNS as an adjunct to ongoing ASM therapy, compared to the strategy of using only ASMs in the treatment of people with DRE, from an English National Health Service perspective.

METHODS

A cohort state transition model was developed in Microsoft Excel to simulate costs and QALYs of the VNS + ASM and ASM only strategies. Patients could transition between five health states, using a 3-month cycle length. Health states were defined by an expected percentage reduction in seizure frequency, derived from randomized control trial data. Costs included the VNS device as well as its installation, setup, and removal; ASM therapy; adverse events associated with VNS (dyspnea, hoarseness, and cough); and health-state costs associated with epilepsy including hospitalizations, emergency department visits, neurologist visits, and primary care visits. A range of sensitivity analyses, including probabilistic sensitivity analysis, were run to assess the impact of parameter and structural uncertainty.

RESULTS

In the base case, VNS + ASM had an estimated incremental cost-effectiveness ratio (ICER) of £17,771 per QALY gained compared to ASMs alone. The cost-effective ICER was driven by relative reductions in expected seizure frequency and the differences in health care resource use associated therewith. Sensitivity analyses found that the amount of resource use per epilepsy-related health state was a key driver of the cost component.

CONCLUSIONS

VNS is expected to be a cost-effective intervention in the treatment of DRE in the English National Health Service.

Psychosocial profiles and their predictors in epilepsy using patient-reported outcomes and machine learning

OBJECTIVE

To apply unsupervised machine learning to patient-reported outcomes to identify clusters of epilepsy patients exhibiting unique psychosocial characteristics.

METHODS

Consecutive outpatients seen at the Calgary Comprehensive Epilepsy Program outpatient clinics with complete patient-reported outcome measures on quality of life, health state valuation, depression, and epilepsy severity and disability were studied. Data were acquired at each patient's first clinic visit. We used k-means++ to segregate the population into three unique clusters. We then used multinomial regression to determine factors that were statistically associated with patient assignment to each cluster.

RESULTS

We identified 462 consecutive patients with complete patient-reported outcome measure (PROM) data. Post hoc analysis of each cluster revealed one reporting elevated measures of psychosocial health on all five PROMs ("high psychosocial health" cluster), one with intermediate measures ("intermediate" cluster), and one with poor overall measures of psychosocial health ("poor psychosocial health" cluster). Failing to achieve at least 1 year of seizure freedom (relative risk [RR] = 4.34, 95% confidence interval [CI] = 2.13-9.09) predicted placement in the "intermediate" cluster relative to the "high" cluster. In addition, failing to achieve seizure freedom, social determinants of health, including the need for partially or completely subsidized income support (RR = 6.10, 95% CI = 2.79-13.31, P < .001) and inability to drive (RR = 4.03, 95% CI = 1.6-10.00, P = .003), and a history of a psychiatric disorder (RR = 3.16, 95% CI = 1.46-6.85, P = .003) were associated with the "poor" cluster relative to the "high" cluster.

SIGNIFICANCE

Seizure-related factors appear to drive placement in the "intermediate" cluster, with social determinants driving placement in the "poor" cluster, suggesting a threshold effect. Precision intervention based on cluster assignment, with an initial emphasis on improving social support and careful titration of medications for those reporting the worst psychosocial health, could help optimize health for patients with epilepsy.

Testing the validity and responsiveness of a new cancer-specific health utility measure (FACT-8D) in relapsed/refractory mantle cell lymphoma, and comparison to EQ-5D-5L

BACKGROUND

The FACT-8D is a new cancer-specific, preference-based measure (PBM) of health, derived from the Functional Assessment of Cancer Therapy - General (FACT-G) questionnaire. The FACT-8D's measurement properties have not been tested to date. We assessed it's validity and responsiveness in relapsed/refractory mantle cell lymphoma (RR MCL) and compared the results to the EQ-5D-5L.

METHODS

Blinded analysis of pooled data from a phase 3 clinical trial. FACT-8D baseline and follow-up data (weeks 4, 7, 16, 31) were scored using Australian preference weights, the first available value-set. Convergent validity was assessed by estimating baseline correlations with the FACT-Lym total score, Trial Outcome Index (TOI), FACT-Lym lymphoma-specific sub-scale (LymS), EQ-5D Visual Analog Scale (VAS), and haemoglobin (HgB). Relevant clinical variables were used to categorise patients to test known groups' validity and responsiveness was investigated using data from baseline (n = 250) and week 31 (n = 130). Results were compared with EQ-5D-5L, scored using the UK 3L crosswalk and the 5L England value-sets.

RESULTS

The FACT-8D showed good convergent validity and responsiveness; baseline Pearson correlation coefficients between FACT-8D Index scores and other PRO measures were moderate to very strong (range: 0.49 for the EQ-VAS to 0.79 for FACT TOI) and the size of the change in FACT-8D Index scores at week 31 differed significantly (p < 0.005) between patients categorised as improved, worsened or stable using the FACT-Lym total score, LymS, and HgB. However, when assessing known groups' validity, FACT-8D failed to discriminate between patients categorised by health status on four of the seven variables analysed. Overall, FACT-8D and EQ-5D-5L performed similarly, although EQ-5D-5L showed better known groups' validity.

CONCLUSIONS

This is the first investigation into the psychometric properties of the FACT-8D. In this RR MCL trial dataset, it showed good convergent validity and responsiveness, but poorer known groups' validity, and EQ-5D performed as well or better on the tests conducted. The FACT-8D may offer an alternative method to generate utilities for the cost-effectiveness analysis of cancer treatments but needs further testing in other types of cancer patients. Evaluation of utility gains may have been limited by high baseline performance status in this RR MCL trial sample.

Economic Value of Adjunctive Brivaracetam Treatment Strategy for Focal Onset Seizures in Finland

Introduction

There is an unmet need for well-tolerated antiepileptic drugs (AEDs) that effectively control focal onset seizures. This study aimed to evaluate the economic value of new AEDs in the treatment of focal onset seizure, with or without secondary generalization, in Finnish adults and adolescents with epilepsy, comparing brivaracetam with perampanel as adjunctive AEDs.

Methods

Economic value was assessed using cost-utility analysis. Periods of AED initiation, titration, response assessment (seizure freedom, ≥ 50% reduction, no response), switching in no response or treatment-emergent adverse events (TEAEs), and death were simulated using a discrete-event simulation model. Responses and switching were simulated based on a comprehensive Bayesian network meta-analysis. The primary modeled outcome was the 3%/year discounted incremental cost-effectiveness ratio (ICER). Discounted quality-adjusted life-years (QALYs), payer costs (year 2017 Euro) per patient, and net monetary benefit (NMB) were secondary outcomes. Probabilistic and comprehensive deterministic sensitivity analyses were conducted.

Results

Brivaracetam was more efficacious and had fewer TEAEs than perampanel and other AEDs. Modeled average 5-year QALYs and costs were 3.671 and €28,297 for brivaracetam and 3.611 and €27,979 for perampanel, respectively. The resulting ICER for brivaracetam versus perampanel was only €5345/QALY gained in a deterministic base case scenario. Brivaracetam had a positive NMB and high probability of cost-effectiveness of €1190 and 71% or €1944 and 80% with the assumed willingness to pay of €25,358 or €38,036/QALY gained, respectively. The primary result was robust, with a positive NMB persistent in all sensitivity analysis scenarios. When switching from brivaracetam to perampanel was excluded from the modeling or switching from perampanel to brivaracetam was included, brivaracetam was cost-saving and more effective than perampanel (dominant).

Conclusion

These simulated comparisons demonstrated that brivaracetam was more effective and potentially also more affordable than perampanel. Thus, brivaracetam is likely a cost-effective and net beneficial alternative to perampanel for treatment of focal onset seizures.

Plain Language Summary

Plain language summary available for this article.

Electronic supplementary material

The online version of this article (10.1007/s12325-019-01155-6) contains supplementary material, which is available to authorized users.

A feasibility assessment of functioning and quality-of-life patient-reported outcome measures in adult epilepsy clinics: A systematic review

OBJECTIVE

The objective of the study was to identify functioning and quality-of-life (QOL) patient-reported outcome measurements (PROMs) feasible for use in the waiting room of adult epilepsy clinics.

MATERIAL AND METHODS

We searched PubMed and Web of Science for articles on in English, Spanish, Portuguese, Italian, and French published by the end of February 15th, 2019. We screened retrieved titles and abstracts looking for publications that reported the use of PROMs to measure functioning and QOL in epilepsy. The authors, clinical experts, and patient advocates from the Epilepsy Foundation of America conceptualized a set of desirable feasibility attributes for PROMs implementation in the waiting room of adult epilepsy clinics. These attributes included brief time for completion (i.e., ≤3 min), free cost, coverage of four minimum QOL domains and respective facets, and good evidence of psychometric properties. We defined QOL domains according to the World Health Organization's classification and created psychometric appraisal criteria based on the Food and Drug Administration's (FDA) Guidance.

RESULTS

Eighteen candidate instruments were identified and compared with respect to desirable attributes for use in adult epilepsy clinics. We found that the Quality-of-life in epilepsy (QOLIE)-10 and Patient-Reported Outcome Measurement Information System-10 (PROMIS-10) were the most feasible PROMs for implementation in adult epilepsy clinics based on our criteria. The QOLIE-10 and PROMIS-10 still lack ideal evidence of responsiveness in people with epilepsy.

CONCLUSION

This is the first systematic review that aimed to assess feasibility properties of available functioning and QOL PROMs. The QOLIE-10 and PROMIS-10 are potentially feasible instruments for implementation in the waiting room of adult epilepsy clinics. Further studies assessing the responsiveness of these PROMs are needed and will contribute to the selection of the most appropriate instrument for longitudinal use in adult epilepsy clinical practice.

Comparisons of direct and indirect utilities in adult epilepsy populations: A systematic review

OBJECTIVE

Epilepsy is common and carries substantial morbidity, and therefore identifying cost-effective health interventions is essential. Cost-utility analysis is a widely used method for such analyses. For this, health conditions are rated in terms of utilities, which provide a standardized score to reflect quality of life. Utilities are obtained either indirectly using quality of life questionnaires, or directly from patients or the general population. We sought to describe instruments used to estimate utilities in epilepsy populations, and how results differ according to methods used.

METHODS

We undertook a systematic review of studies comparing at least two instruments for obtaining utilities in epilepsy populations. MEDLINE, Embase, ScienceDirect, Cochrane Library, Google Scholar, and gray literature were searched from inception to June 2019. Mean utilities were recorded and compared for each method.

RESULTS

Of the 38 unique records initially identified, eight studies met inclusion criteria. Utilities were highest for direct "tradeoff" methods, obtained via instruments including standard gamble (0.93) and time tradeoff (0.92), compared to indirect methods, obtained via instruments including EuroQoL five-dimensional form (range = 0.72-0.86) and Health Utilities Index Mark 3 (range = 0.52-0.71). Visual analog scale (VAS), a direct "nontradeoff" instrument, provided equal or lower utilities (range = 68.0-79.8) compared to indirect instruments.

SIGNIFICANCE

Direct methods, with the important exception of VAS, may provide higher utilities than indirect methods. More studies are needed to identify the most appropriate utility instruments for epilepsy populations, and to investigate whether there is variation between utilities for different types of epilepsy and other patient- and disease-specific factors.

Comparison of EQ-5D-5L and SPVU-5D for measuring quality of life in patients with venous leg ulcers in an Australian setting

PURPOSE

Given the importance of measuring health-related quality of life (HRQoL) for cost-utility studies, this study aimed to determine the validity and responsiveness of two preference-based HRQoL instruments, the EuroQol-five dimensions-five levels questionnaire (EQ-5D-5L) and the Sheffield Preference-based Venous Ulcer questionnaire (SPVU-5D) in patients with venous leg ulcers (VLUs) in an Australian setting.

METHODS

This study analysed de-identified data collected from 80 patients with VLUs recruited by a prospective study in Brisbane, Queensland, Australia. Patients were asked to complete EQ-5D-5L and SPVU-5D surveys at baseline, 1-month, 3-month and 6-month follow-up as part of the prospective study. Baseline data and follow-up data were pooled to test the construct validity and level of agreement of the two instruments. Follow-up data were used to test the responsiveness.

RESULTS

The ceiling effects were negligible for EQ-5D-5L and SPVU-5D utility scores. Both instruments were able to discriminate between healed VLU and unhealed VLU and showed great responsiveness when healing status changed over time. Weak to strong correlations were found between dimensions of EQ-5D-5L and SPVU-5D. The utility scores produced from EQ-5D-5L were generally lower.

CONCLUSIONS

This study found that both EQ-5D-5L and SPVU-5D were valid and responsive in detecting change of VLU healing status among a small Australian population. Both instruments may be used in economic evaluation studies that involve patients with healed or unhealed VLUs. However, given the limitations presented in this study, further research is necessary to make sound recommendations on the preferred instrument in economic evaluation of VLU-related interventions.

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.

A comparison of the responsiveness of EQ-5D-5L and the QOLIE-31P and mapping of QOLIE-31P to EQ-5D-5L in epilepsy

OBJECTIVE

To investigate the responsiveness of and correlation between the EQ-5D-5L and the QOLIE-31P in patients with epilepsy, and develop a mapping function to predict EQ-5D-5L values based on the QOLIE-31P for use in economic evaluations.

METHODS

The dataset was derived from two clinical trials, the ZMILE study in the Netherlands and the SMILE study in the UK. In both studies, patients' quality of life using the EQ-5D-5L and QOLIE-31P was measured at baseline and 12 months follow-up. Spearman's correlations, effect sizes (EF) and standardized response means (SRM) were calculated for both the EQ-5D-5L and QOLIE-31P domains and sub scores. Mapping functions were derived using ordinary least square (OLS) and censored least absolute deviations models.

RESULTS

A total of 509 patients were included in this study. Low to moderately strong significant correlations were found between both instruments. The EQ-5D-5L showed high ceiling effects and small EFs and SRMs, whereas the QOLIE-31P did not show ceiling effects and also showed small to moderate EFs and SRMs. Results of the different mapping functions indicate that the highest adjusted R ² we were able to regress was 0.265 using an OLS model with squared terms, leading to a mean absolute error of 0.103.

CONCLUSIONS

Results presented in this study emphasize the shortcomings of the EQ-5D-5L in epilepsy and the importance of the development of condition-specific preference-based instruments which can be used within the QALY framework. In addition, the usefulness of the constructed mapping function in economic evaluations is questionable.

EQ-5D-based utilities and healthcare utilization in Thai adults with chronic epilepsy

Quality of life and resource use are key parameters that justify economic values in treatments for epilepsy. Health profiles and service utilization were assessed in 224 adults with 15.7years of epilepsy in two super-tertiary care facilities in Thailand. The European Quality of Life, 5-Dimension (EQ-5D)-based utilities and subsequent outpatient (OP) visits and hospitalizations were determined with respect to seizure control outcomes that were assessed by neurologists. Mean utility and visual analogue scale (VAS) scores were respectively higher in 67 patients who are seizure-free (0.82 and 78.9) than in 157 patients who had uncontrolled or persistent seizures, which were divided into seizure reduction (0.79 and 75.5) and no improvement in seizure frequency (0.72 and 73.5). Controlling for patient characteristics, those who are seizure-free had significantly higher utility and VAS scores than those with no improvement by 0.10 (95% confidence interval (CI): 0.03-0.17) and 6.25 (95% CI: 0.09-12.41), respectively. Seizure-free patients were less likely to report pain or discomfort, as compared with patients with seizure reduction (odds ratio (OR): 0.41, 95% CI: 0.19-0.90) and patients with no improvement (OR: 0.32, 95% CI: 0.13-0.75). Over a six-month period, mean OP visits were significantly lower in seizure-free patients (2.27 times) than in those with seizure reduction (3.00 times) and those with no improvement (4.08 times). Mean hospitalizations over 12months among the three groups were 0.03, 0.24, and 0.14 times, respectively. For persistent seizures, 50% received only conventional antiepileptic drugs (AEDs). When epilepsy treatments are considered for their costs and effectiveness, utilities and healthcare use, conditional on seizure control status, can be applied for further analyses.

Health-related quality of life in patients with poststroke epilepsy

BACKGROUND

Lesional epilepsy is an important long-term sequela of stroke. Data on health-related quality of life (HrQoL) in patients with poststroke epilepsy are limited. We investigated HrQoL in patients with epilepsy after ischemic stroke and identified independent HrQoL-determinants.

METHODS AND PATIENTS

All patients with acute ischemic stroke, who were permanent residents in the district Marburg-Biedenkopf (Hessia, Germany, reference population 240,000 inhabitants) were recruited within 12months in the population-based Marburg Stroke Register (MARSTREG). Follow-up visits were performed after 6, 12, and 24months, and patients who developed poststroke epilepsy were identified. Data on demographics, antiepileptic drugs (AEDs), stroke severity (National Institute of Heath Stroke Scale (NIHSS), Barthel-Index, modified Rankin Scale), depression (Geriatric Depression Scale), and HrQoL (EQ-5D and EQ VAS) were collected. A multiple regression analysis was performed to identify HrQoL-determinants.

RESULTS

Among the study participants (n=374), 23 (6.1%) developed poststroke epilepsy. The HrQoL of patients with poststroke epilepsy was reduced in comparison with patients without seizures (24-month follow-up: EuroQol Visual Analogue Scale (EuroQol-VAS): 55.3±10.7 versus 64.2±11.4, p=0.03). Seizure frequency, depression, and functional impairment (Barthel-Index) were identified as independent determinants of HrQoL. The adjustment of AEDs between 6-month and 24-month follow-ups resulted in decrease of seizure frequency by 40% and reduction of complications (dizziness by 27.8%, nausea by 52.2%, fatigue by 84.2%).

CONCLUSION

Lesional epilepsy is associated with decreased HrQoL in patients with stroke. We identified HrQoL-determinants, which would improve the management of patients with poststroke epilepsy. These determinants include proper adjustment of AEDs with reduction of seizure frequency, treatment of depression, and focused rehabilitation programs for poststroke epilepsy.