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

A Cost-Utility Analysis of Add-On Cannabidiol Versus Usual Care Alone for the Treatment of Seizures Associated with Tuberous Sclerosis Complex in England and Wales

OBJECTIVES

The aim of this study was to evaluate the cost effectiveness of plant-derived highly purified cannabidiol (Epidyolex® in the UK; 100 mg/mL oral solution) as an add-on treatment to usual care for the management of treatment-refractory seizures associated with tuberous sclerosis complex (TSC) in patients aged ≥ 2 years.

METHODS

A cohort-based model was developed using a National Health Service perspective and lifetime horizon. Health states were based on weekly seizure frequency and seizure-free days, utilizing patient-level data from the GWPCARE6 trial (ClinicalTrials.gov identifier: NCT02544763). Two independent regression models were applied to individual patient-level data to predict seizure-free days and seizure frequency. Healthcare resource utilization data were sourced from a Delphi panel, and patient and caregiver health-related quality of life values were elicited using vignettes valued by the general public. Outcomes relating to TSC-associated neuropsychiatric disorders were modeled with costs and quality-adjusted life-years sourced from published literature.

RESULTS

In the base case, compared with usual care alone, 12 mg/kg/day cannabidiol was associated with an incremental cost-effectiveness ratio (ICER) of £23,797. The National Institute for Health and Care Excellence disease severity modifier reduced the ICER to £19,831. Probabilities of cost effectiveness at willingness-to-pay thresholds of £20,000 and £30,000 were 30% and 52%, respectively, for the base case and 39% and 66%, respectively, for the disease severity modifier. Results were robust to sensitivity and scenario analyses.

CONCLUSIONS

At 12 mg/kg/day and an ICER threshold of £20,000-£30,000, we provide evidence for the cost effectiveness of add-on cannabidiol treatment for patients with TSC-associated seizures aged ≥ 2 years who are refractory to current treatment.

Work productivity, quality of life, and care needs: An unfolding epilepsy burden revealed in the Australian Epilepsy Project pilot study

OBJECTIVE

Epilepsy is a common and serious neurological disorder. This cross-sectional analysis addresses the burden of epilepsy at different stages of the disease.

METHODS

This pilot study is embedded within the Australian Epilepsy Project (AEP), aiming to provide epilepsy support through a national network of dedicated sites. For this analysis, adults aged 18-65 years with first unprovoked seizure (FUS), newly diagnosed epilepsy (NDE), or drug-resistant epilepsy (DRE) were recruited between February-August 2022. Baseline clinicodemographic data were collected from the participants who completed questionnaires to assess their quality of life (QOLIE-31, EQ-5D-5L), work productivity (Work Productivity and Activity Impairment [WPAI]), and care needs. Univariate analysis and multivariate regression was performed.

RESULTS

172 participants formed the study cohort (median age 34, interquartile range [IQR]: 26-45), comprising FUS (n = 44), NDE (n = 53), and DRE (n = 75). Mean QOLIE-31 score was 56 (standard deviation [SD] ± 18) and median EQ-5D-5L score was 0.77 (IQR: 0.56-0.92). QOLIE-31 but not EQ-5D-5L scores were significantly lower in the DRE group compared to FUS and NDE groups (p < 0.001). Overall, 64.5% of participants participated in paid work, with fewer DRE (52.0%) compared with FUS (76.7%) and NDE (72.5%) (p < 0.001). Compared to those not in paid employment, those in paid employment had significantly higher quality of life scores (p < 0.001). Almost 5.8% of participants required formal care (median 20 h/week, IQR: 12-55) and 17.7% required informal care (median 16 h/week, IQR: 7-101).

SIGNIFICANCE

Epilepsy is associated with a large burden in terms of quality of life, productivity and care needs.

PLAIN LANGUAGE SUMMARY

This is a pilot study from the Australian Epilepsy Project (AEP). It reports health economic data for adults of working age who live with epilepsy. It found that people with focal drug-resistant epilepsy had lower quality of life scores and were less likely to participate in paid employment compared to people with new diagnosis epilepsy. This study provides important local data regarding the burden of epilepsy and will help researchers in the future to measure the impact of the AEP on important personal and societal health economic outcomes.

Effectiveness of Seizure Dogs for People With Severe Refractory Epilepsy: Results From the EPISODE Study

BACKGROUND AND OBJECTIVES

The aim of this study was to evaluate whether people living with severe medically refractory epilepsy (PSRE) benefit from a seizure dog.

METHODS

An individual-level stepped-wedge randomized controlled trial was conducted. The study was conducted in the Netherlands among adults with daily to weekly seizures. All participants were included simultaneously (on June 1, 2019) while receiving usual care. Then, during the 36-month follow-up, they received a seizure dog in a randomized sequence. Participants kept a seizure diary and completed 3-monthly surveys. Seizure frequency was the primary outcome. Secondary outcomes included seizure-free days, seizure severity, health-related quality of life (HRQoL), and well-being. Data were analyzed using generalized linear mixed modeling (GLMM). The models assumed a delayed intervention effect, starting when the seizure dog reached an advanced stage of training. Effects were calculated as changes per 28-day period with the intervention.

RESULTS

Data were collected from 25 participants, of whom 20 crossed over to the intervention condition. The median follow-up was 19 months with usual care and 12 months with the intervention. On average, participants experienced 115 (SD 164) seizures per 28-day period in the usual care condition and 73 (SD 131) seizures in the intervention condition. Seven participants achieved a reduction of 50% or more at the end of follow-up. GLMM indicated a 3.1% decrease in seizure frequency for each consecutive 28-day period with the intervention (0.969, 95% CI 0.960-0.977). Furthermore, an increase in the number of seizure-free days was observed (1.012, 95% CI 1.009, 1.015), but no effect on seizure severity measured with the NHS3. Generic HRQoL scores improved, as reflected in the decrease in EQ-5D-5L utility decrement (0.975, 95% CI 0.954-0.997). Smaller improvements were observed on overall self-rated HRQoL, epilepsy-specific HRQoL, and well-being, measured with the EQ VAS, QOLIE-31-P, and ICECAP-A, respectively.

DISCUSSION

Seizure dogs reduce seizure frequency, increase the number of seizure-free days, and improve the quality of life of PSRE. The magnitude of the effect on generic HRQoL indicates that seizure dogs benefit PSRE beyond the impact on seizure frequency alone. Early discontinuation of seizure dog partnerships suggests that this intervention is not suitable for all PSRE and requires further study.

TRIAL REGISTRATION INFORMATION

This study was registered in the Dutch Trial Register (NL6682) on November 28, 2017. Participants were enrolled on June 1, 2019.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that seizure dogs are associated with a decrease in seizure frequency in adult patients with medically refractory epilepsy.

Determinants of quality of life in adults with epilepsy: a multicenter, cross-sectional study from Germany

BACKGROUND

Assessment of quality of life (QoL) has become an important indicator for chronic neurological diseases. While these conditions often limit personal independence and autonomy, they are also associated with treatment-related problems and reduced life expectancy. Epilepsy has a tremendous impact on the QoL of patients and their families, which is often underestimated by practitioners. The aim of this work was to identify relevant factors affecting QoL in adults with epilepsy.

METHODS

This cross-sectional, multicenter study was conducted at four specialized epilepsy centers in Germany. Patients diagnosed with epilepsy completed a standardized questionnaire focusing on QoL and aspects of healthcare in epilepsy. Univariate regression analyses and pairwise comparisons were performed to identify variables of decreased QoL represented by the overall Quality of Life in Epilepsy Inventory (QOLIE-31) score. The variables were then considered in a multivariate regression analysis after multicollinearity analysis.

RESULTS

Complete datasets for the QOLIE-31 were available for 476 patients (279 [58.6%] female, 197 [41.4%] male, mean age 40.3 years [range 18-83 years]). Multivariate regression analysis revealed significant associations between low QoL and a high score on the Liverpool Adverse Events Profile (LAEP; beta=-0.28, p < 0.001), Hospital Anxiety and Depression Scale - depression subscale (HADS-D; beta=-0.27, p < 0.001), Neurological Disorders Depression Inventory in Epilepsy (NDDI-E; beta=-0.19, p < 0.001), revised Epilepsy Stigma Scale (beta=-0.09, p = 0.027), or Seizure Worry Scale (beta=-0.18, p < 0.001) and high seizure frequency (beta = 0.14, p < 0.001).

CONCLUSION

Epilepsy patients had reduced QoL, with a variety of associated factors. In addition to disease severity, as measured by seizure frequency, the patient's tolerability of anti-seizure medications and the presence of depression, stigma, and worry about new seizures were strongly associated with poor QoL. Diagnosed comorbid depression was underrepresented in the cohort; therefore, therapeutic decisions should always consider individual psychobehavioral and disease-specific aspects. Signs of drug-related adverse events, depression, fear, or stigmatization should be actively sought to ensure that patients receive personalized and optimized treatment.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS00022024; Universal Trial Number: U1111-1252-5331).

Burden of migraine in patients attending Belgian headache specialists: real-world evidence from the BECOME study

INTRODUCTION

Migraine is a primary headache disorder, which imposes a major burden on the sufferers. The BECOME study (Burden of migrainE in specialist headache Centers treating patients with prOphylactic treatMent failurE) attempted to characterize and assess the prevalence, burden and healthcare resource utilization of migraine patients presenting in specialized headache centers in Europe and Israel. In this paper, we will describe the patient characteristics of the Belgian headache centers.

METHODS

The BECOME study was a prospective, non-interventional, cross-sectional study consisting of two parts. In the first part of the study, data were collected from subjects with a diagnosis of migraine. Subsequently, patients with ≥ 4 monthly migraine days (MMD) and ≥ 1 prior preventive treatment failure (PPTF) filled out validated questionnaires to assess the burden of disease.

RESULTS

In part 1 of the Belgian study population (N = 806), 45% of patients reported ≥ 8 MMD and 25% had failed ≥ 4 preventive treatments. In part 2 (N = 90), more than 90% of patients reported having severe impact of headache on daily life and having severe migraine-related disability. The impact was the highest for patients with ≥ 15 MMD, however, even within the patient population with < 8 MMD, the burden was significant. Almost 40% of the study population suffered from anxiety.

CONCLUSIONS

These findings in the Belgian sample of the BECOME study demonstrate the substantial burden and unmet need for the management of difficult-to-treat migraine.

Mapping Studies to Estimate Health-State Utilities From Nonpreference-Based Outcome Measures: A Systematic Review on How Repeated Measurements are Taken Into Account

OBJECTIVES

Mapping algorithms are developed using data sets containing patient responses to a preference-based questionnaire and another health-related quality-of-life questionnaire. When data sets include repeated measurements from the same individuals over time, the assumption of observations' independence, required by standard models, is violated, and standard errors are underestimated. This review aimed to identify how studies deal with methodological challenges of repeated measurements, provide an overview of practice to date, and potential implications for future work.

METHODS

We conducted a systematic literature search of MEDLINE, Cumulative Index to Nursing and Allied Health Literature, specialized databases, and previous systematic reviews. A data template was used to extract, among others, start and target instruments if the data set(s) used for estimation and validation had repeated measurements per patient, used regression techniques, and which (if any) adjustments were made for repeated measurements.

RESULTS

We identified 278 publications developing at least 1 mapping algorithm. Of the 278 publications, 121 used a data set with repeated measurements, among which 92 used multiple time points for estimation, and 39 selected specific time points to have 1 observation per participant. A total of 36 studies did not account for repeated measurements. An adjustment was conducted using cluster-robust standard errors (21), random-effects models (30), generalized estimating equations (7), and other methods (7).

CONCLUSIONS

The inconsistent use of methods to account for interdependent observations in the literature indicates that mapping guidelines should include recommendations on how to deal with repeated measurements, and journals should update their guidelines accordingly.

Cost-effectiveness of cenobamate for focal seizures in people with drug-resistant epilepsy

OBJECTIVE

This study was undertaken to estimate the cost-effectiveness of add-on cenobamate in the UK when used to treat drug-resistant focal seizures in adults who are not adequately controlled with at least two prior antiseizure medications, including at least one used adjunctively.

METHODS

We estimated the cost per quality-adjusted life-year (QALY) for cenobamate compared to brivaracetam, eslicarbazepine, lacosamide, and perampanel in the UK National Health Service over a lifetime time horizon. We used a Markov cohort structure to determine response to treatment, using pooled data from three long-term studies of cenobamate. A network meta-analysis informed the likelihood of response to therapy with brivaracetam, eslicarbazepine, lacosamide, and perampanel relative to cenobamate. Once individuals discontinued treatment, they transitioned to subsequent treatment health states, including other antiseizure medicines, surgery, and vagus nerve stimulation. Costs included treatment, administration, routine monitoring, event management, and adverse events. Published evidence and expert opinion informed the likelihood of response to subsequent treatments, associated adverse events, and costs. Utility data were based on Short-Form six-dimension form utility. Discounting was applied at 3.5% per annum as per National Institute for Health and Care Excellence guidance. Uncertainty was explored through deterministic and probabilistic sensitivity analyses.

RESULTS

In the base case, cenobamate led to cost savings of £51 967 (compared to brivaracetam), £21 080 (compared to eslicarbazepine), £33 619 (compared to lacosamide), and £28 296 (compared to perampanel) and increased QALYs of 1.047 (compared to brivaracetam), 0.598 (compared to eslicarbazepine), 0.776 (compared to lacosamide), and 0.703 (compared to perampanel) per individual over a lifetime time horizon. Cenobamate also dominated the four drugs across most sensitivity analyses. Differences were due to reduced seizure frequency with cenobamate relative to comparators.

SIGNIFICANCE

Cenobamate improved QALYs and was less costly than brivaracetam, eslicarbazepine, lacosamide, and perampanel. Therefore, cenobamate may be considered as a cost-effective adjunctive antiseizure medication for people with drug-resistant focal seizures.

Generating EQ-5D-5L health utility scores from BASDAI and BASFI: a mapping study in patients with axial spondyloarthritis using longitudinal UK registry data

BACKGROUND

Preference-based health-state utility values (HSUVs), such as the EuroQol five-dimensional questionnaire (EQ-5D-5L), are needed to calculate quality-adjusted life-years (QALYs) for cost-effectiveness analyses. However, these are rarely used in clinical trials of interventions in axial spondyloarthritis (axSpA). In these cases, mapping can be used to predict HSUVs.

OBJECTIVE

To develop mapping algorithms to estimate EQ-5D-5L HSUVs from the Bath Ankylosing Disease Activity Index (BASDAI) and the Bath Ankylosing Spondylitis Functional Index (BASFI).

METHODS

Data from the British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) provided 5122 observations with complete BASDAI, BASFI, and EQ-5D-5L responses covering the full range of disease severity. We compared direct mapping using adjusted limited dependent variable mixture models (ALDVMMs) and optional inclusion of the gap between full health and the next feasible value with indirect response mapping using ordered probit (OPROBIT) and generalised ordered probit (GOPROBIT) models. Explanatory variables included BASDAI, BASFI, and age. Metrics to assess model goodness-of-fit and performance/accuracy included Akaike and Bayesian information criteria (AIC/BIC), mean absolute error (MAE) and root mean square error (RMSE), plotting predictive vs. observed estimates across the range of BASDAI/BASFI and comparing simulated data with the original data set for the preferred/best model.

RESULTS

Overall, the ALDVMM models that did not formally include the gap between full health and the next feasible value outperformed those that did. The four-component mixture models (with squared terms included) performed better than the three-component models. Response mapping using GOPROBIT (no squared terms included) or OPROBIT (with squared terms included) offered the next best performing models after the three-component ALDVMM (with squared terms). Simulated data of the preferred model (ALDVMM with four-components) did not significantly underestimate uncertainty across most of the range of EQ-5D-5L values, however the proportion of data at full health was underrepresented, likely due in part to model fitting on a small number of observations at this point in the actual data (4%).

CONCLUSIONS

The mapping algorithms developed in this study enabled the generation of EQ-5D-5L utilities from BASDAI/BASFI. The indirect mapping equations reported for the EQ-5D-5L facilitate the calculation of the EQ-5D-5L utility scores using other UK and country-specific value sets.

Burden of illness in people with medically refractory epilepsy who suffer from daily to weekly seizures: 12-month follow-up of participants in the EPISODE study

BACKGROUND

A small group of people with epilepsy suffers from frequent seizures despite the available pharmacological and non-pharmacological interventions. The impact of epilepsy on these people extends beyond health-related quality of life (HRQoL), impacting a person's broader well-being and ability to participate in society. This study describes the burden of medically refractory epilepsy in people who suffer from daily to weekly seizures, in terms of HRQoL, well-being, and societal costs.

METHODS

Data from the EPISODE study on (cost-) effectiveness of seizure dogs for adults with severe medically refractory epilepsy were used, collected in 25 patients during the first 12 months before they were partnered with a certified seizure dog. Data comprised seizure diaries covering 365 days and five three-monthly surveys, including the EQ-5D-5L, QOLIE-31-P, and ICECAP-A to measure HRQoL and well-being. A societal perspective was applied to estimate costs using the iMCQ and iPCQ questionnaires about healthcare use, informal care, and productivity losses.

RESULTS

Daily seizure frequency and survey data were collected in 25 patients. A minimum of 114 observations was available for each instrument included in the survey. A total of 80% of participants experienced seizures on three or more days per week, with a median ranging from 1 to 17 seizures per seizure day. The mean EQ-5D-5L utility score was 0.682 (SD 0.235), which is considerably lower than the age-adjusted general population average. The mean QOLIE-31-P and ICECAP-A scores were 55.8 (SD 14.0) and 0.746 (SD 0.172), respectively. The average annual total cost amounted to €39,956 (range €3,804-€132,64). Informal care accounted for the largest share of costs (50%); those who received informal care reported, on average, 26 h per week (SD 30).

CONCLUSIONS

Severe medically refractory epilepsy is associated with a considerable burden of illness at the patient and societal level. People with this condition have significantly reduced HRQoL and well-being and are limited in their ability to work while having substantial medical costs and a strong dependency on informal care.

Mapping analysis to predict SF-6D utilities from health outcomes in people with focal epilepsy

BACKGROUND

Focal-onset seizures (FOS) are commonly experienced by people with epilepsy and have a significant impact on quality of life (QoL). This study aimed to develop a mapping algorithm to predict SF-6D values in adults with FOS for use in economic evaluations of a new treatment, cenobamate.

METHODS

An online survey, including questions on disease history, SF-36, and an epilepsy-specific measure (QOLIE-31-P) was administered to people with FOS in the UK, France, Italy, Germany, and Spain. A range of regression models were fitted to SF-6D scores including direct and response mapping approaches.

RESULTS

361 individuals were included in the analysis. In the previous 28 days, the mean number of FOS experienced was 3, (range 0-43) and the mean longest period of consecutive days without experiencing a seizure was 14 days (range 1-28 days or more). Mean responses on all SF-36 dimensions were lower than general population norms. Mean SF-6D and QOLIE-31-P scores were 0.584 and 45.72, respectively. The best performing model was the ordinary least squares (OLS), with root mean squared error and mean absolute error values of 0.0977 and 0.0742, respectively. Explanatory variables which best predicted SF-6D included seizure frequency, severity, freedom, and age.

CONCLUSION

People with uncontrolled FOS have poor QoL. The mapping algorithm enables the prediction of SF-6D values from clinical outcomes in people with FOS. It can be applied to outcome data from clinical trials to facilitate cost-utility analysis.

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.

Patient and Caregiver Health State Utilities in Tuberous Sclerosis Complex

BACKGROUND

Tuberous sclerosis complex (TSC) is a rare multisystem disorder often associated with treatment-resistant epilepsy. Cost-effectiveness analysis for new antiseizure medications typically requires health state utilities (HSUs) that reflect the burden of a given condition.

OBJECTIVE

This study aimed to estimate HSUs, with a focus on valuing the impact of seizure type and seizure frequency on health-related quality of life (HRQL) for patients with TSC and their caregivers.

METHODS

A targeted literature review and qualitative research with healthcare professionals and caregivers informed the development of health state vignettes describing the experience of living with TSC or caring for a child with TSC. Vignettes were evaluated in interviews with the UK general population using the time trade-off (TTO) method.

RESULTS

Sixteen vignettes were developed describing patient HRQL (n = 8) and caregiver HRQL (n = 8). Two hundred interviews were conducted via online video calls due to COVID-19 pandemic restrictions. Two hundred participants evaluated the patient (n = 100) and caregiver (n = 100) health state vignettes. Estimated utility scores varied consistently according to seizure type and seizure frequency. Patient TTO utility scores ranged between -0.234 (highest seizure frequency and multiple seizure types) and 0.725 (seizure-free state). Caregiver TTO utility scores ranged from 0.221 to 0.905.

CONCLUSIONS

Findings highlight the substantial burden of living with TSC and caring for a child with TSC. Patient and caregiver burden was greater for generalised versus focal seizures. The burden was greatest for a combination of both seizure types and worsened with increasing seizure frequency.

Patient and Caregiver Health State Utilities in Lennox-Gastaut Syndrome and Dravet Syndrome

PURPOSE

Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) are rare, treatment-resistant forms of epilepsy characterized by childhood onset of seizures. Cost-effectiveness analysis for new antiseizure medications typically requires health state utilities (HSUs) that reflect the patient and caregiver burden of the relevant conditions. This study aimed to estimate HSUs for LGS and DS. Focus was placed on valuing the impact of seizure frequency and seizure-free days on health-related quality of life (HRQL) for patients and caregivers.

METHODS

Health state vignettes that described the experience of living with and caring for a child with LGS or DS were developed based on a targeted literature review and feedback from interviews with LGS and DS clinical experts and DS caregivers. Vignettes varied by the number of seizures and seizure-free days per month. Twenty-four vignettes were developed that described patient HRQL (6 per condition) and caregiver HRQL (6 per condition) for LGS or DS. Vignettes were evaluated via interviews from the general population in the United Kingdom and Sweden using a visual analog scale and time trade-off (TTO) method. Participants were recruited by interviewers based in different regions of the United Kingdom and Sweden using convenience sampling.

FINDINGS

Two hundred interviews were conducted by video call from March to April 2020. One hundred participants evaluated each of the 6 patient and 6 caregiver vignettes for LGS; a different 100 participants evaluated each of the DS vignettes. The estimated utility values vary consistently according to seizure frequency and number of seizure-free days. Patient TTO utility values range from -0.186 (highest seizure frequency and fewest seizure-free days) to 0.754 (seizure-free state) for LGS and from 0.171 to 0.778 for DS. The caregiver TTO utility values range from 0.032 to 0.810 and 0.510 to 0.881 for LGS and DS, respectively. Fewer seizures and additional seizure-free days are associated with better patient and caregiver HRQL.

IMPLICATIONS

This study estimated utility values for patients with LGS or DS and their caregivers using visual analog scale and TTO valuation among a general public sample. These utility values can be used in cost-effectiveness assessments of new antiseizure medications. The findings indicate the importance of seizure-free days as well as seizure frequency in patient and caregiver HRQL, which may inform the design of future clinical trials.

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.

Mapping of the World Health Organization's Disability Assessment Schedule 2.0 to disability weights using the Multi-Country Survey Study on Health and Responsiveness

OBJECTIVES

To develop and test an internationally applicable mapping function for converting WHODAS-2.0 scores to disability weights, thereby enabling WHODAS-2.0 to be used in cost-utility analyses and sectoral decision-making.

METHODS

Data from 14 countries were used from the WHO Multi-Country Survey Study on Health and Responsiveness, administered among nationally representative samples of respondents aged 18+ years who were non-institutionalized and living in private households. For the combined total of 92,006 respondents, available WHODAS-2.0 items (for both 36-item and 12-item versions) were mapped onto disability weight estimates using a machine learning approach, whereby data were split into separate training and test sets; cross-validation was used to compare the performance of different regression and penalized regression models. Sensitivity analyses considered different imputation strategies and compared overall model performance with that of country-specific models.

RESULTS

Mapping functions converted WHODAS-2.0 scores into disability weights; R-squared values of 0.700-0.754 were obtained for the test data set. Penalized regression models reached comparable performance to standard regression models but with fewer predictors. Imputation had little impact on model performance. Model performance of the generic model on country-specific test sets was comparable to model performance of country-specific models.

CONCLUSIONS

Disability weights can be generated with good accuracy using WHODAS 2.0 scores, including in national settings where health state valuations are not directly available, which signifies the utility of WHODAS as an outcome measure in evaluative studies that express intervention benefits in terms of QALYs gained.

Psychometric properties of the EQ-5D-5L: a systematic review of the literature

PURPOSE

Although the EQ-5D has a long history of use in a wide range of populations, the newer five-level version (EQ-5D-5L) has not yet had such extensive experience. This systematic review summarizes the available published scientific evidence on the psychometric properties of the EQ-5D-5L.

METHODS

Pre-determined key words and exclusion criteria were used to systematically search publications from 2011 to 2019. Information on study characteristics and psychometric properties were extracted: specifically, EQ-5D-5L distribution (including ceiling and floor), missing values, reliability (test-retest), validity (convergent, known-groups, discriminate) and responsiveness (distribution, anchor-based). EQ-5D-5L index value means, ceiling and correlation coefficients (convergent validity) were pooled across the studies using random-effects models.

RESULTS

Of the 889 identified publications, 99 were included for review, representing 32 countries. Musculoskeletal/orthopedic problems and cancer (n = 8 each) were most often studied. Most papers found missing values (17 of 17 papers) and floor effects (43 of 48 papers) to be unproblematic. While the index was found to be reliable (9 of 9 papers), individual dimensions exhibited instability over time. Index values and dimensions demonstrated moderate to strong correlations with global health measures, other multi-attribute utility instruments, physical/functional health, pain, activities of daily living, and clinical/biological measures. The instrument was not correlated with life satisfaction and cognition/communication measures. Responsiveness was addressed by 15 studies, finding moderate effect sizes when confined to studied subgroups with improvements in health.

CONCLUSIONS

The EQ-5D-5L exhibits excellent psychometric properties across a broad range of populations, conditions and settings. Rigorous exploration of its responsiveness is needed.

Factors influencing short-term effectiveness and efficiency of the care provided by Dutch general practice mental health professionals

Introduction

This study examined whether factors related to general practice mental health professionals (GP-MHPs), that is, characteristics of the professional, the function, and the care provided, were associated with short-term effectiveness and efficiency of the care provided by GP-MHPs to adults in Dutch general practice.

Methods

A prospective cohort study was conducted among 320 adults with anxiety or depressive symptoms who had an intake consultation with GP-MHPs (n = 64). Effectiveness was measured in terms of change in quality-adjusted life years (QALYs) 3 months after intake; and efficiency in terms of net monetary benefit (NMB) at 3-month follow-up. A range of GP-MHP-related predictors and patient-related confounders was considered.

Results

Patients gained on average 0.022 QALYs at 3-month follow-up. The mean total costs per patient during the 3-month follow-up period (€3,864; 95% confidence interval [CI]: €3,196-€4,731) decreased compared to that during the 3 months before intake (€5,220; 95% CI: €4,639-€5,925), resulting largely from an increase in productivity. Providing mindfulness and/or relaxation exercises was associated with QALY decrement. Having longer work experience as a GP-MHP (≥2 years) and having 10-20 years of work experience as a mental health care professional were negatively associated with NMB. Furthermore, a higher number of homework exercises tended to be related to less efficient care. Finally, being self-employed and being seconded from an organization in which primary care and mental health care organizations collaborate were related to a positive NMB, while being seconded from a mental health organization tended towards such a relationship.

Conclusions

Findings seem to imply that the care provided by GP-MHPs contributes to improving patients' functioning. Some GP-MHP-related characteristics appear to influence short-term effectiveness and efficiency of the care provided. Further research is needed to confirm and better explain these findings and to examine longer-term effects.

Comparison of clinical efficacy of oxcarbazepine and lamotrigine combined with escitalopram, and impact on prognostic quality of life in treating patients with epilepsy and depressive disorder

This study aimed to investigate the clinical efficacy of oxcarbazepine and lamotrigine combined with escitalopram in treating patients with epilepsy and depressive disorder, and their influence on the prognostic quality of life. A total of 108 patients with epilepsy and depression were selected as research participants. Among them, 53 patients were treated by oxcarbazepine combined with escitalopram (group A) and 55 patients were treated by lamotrigine combined with escitalopram (group B). Following six-month treatment, efficacy, epilepsy frequency and duration, Hamilton Depression Rating (HAMD) and Montgomery-Asberg Depression Rating (MADRS) scores, adverse reactions, improvement of electroencephalogram (EEG) epileptic discharge, quality of life, 1-year drug retention rate and withdrawal reasons of the two groups were compared. There was no remarkable difference in the total efficacy rate between both groups. The number and duration of epileptic seizures, improvement of EEG epileptic discharge and quality of life in the two groups significantly improved after treatment, with no marked difference. HAMD and MADRS scores of patients from group B were significantly lower after treatment compared with those of patients from group A. The incidence rate of adverse reactions in group B was dramatically lower compared with group A, and the 1-year drug retention rate of group B was dramatically higher compared with that in group A. Both oxcarbazepine and lamotrigine combined with escitalopram exhibited good efficacy in patients with epilepsy and depressive disorder, and they may effectively improve the prognostic quality of life of patients. Lamotrigine combined with escitalopram presented with a better antidepressant effect and safety, with higher patient tolerance.

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.

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.

Cost-utility, cost-effectiveness, and budget impact of Internet-based cognitive behavioral therapy for breast cancer survivors with treatment-induced menopausal symptoms

Purpose

Internet-based cognitive behavioral therapy (iCBT), with and without therapist support, is effective in reducing treatment-induced menopausal symptoms and perceived impact of hot flushes and night sweats (HF/NS) in breast cancer survivors. The aim of the current study was to evaluate the cost-utility, cost-effectiveness, and budget impact of both iCBT formats compared to a waiting list control group from the Dutch healthcare perspective.

Methods

A Markov model was constructed with a 5-year time horizon. Costs and health outcomes were measured alongside a randomized controlled clinical trial and included quality-adjusted life years (QALYs), overall levels of menopausal symptoms, and perceived impact of HF/NS. Uncertainty was examined using probabilistic and deterministic sensitivity analyses, together with a scenario analysis incorporating a different perspective.

Results

iCBT was slightly more expensive than the waiting list control, but also more effective, resulting in incremental cost-utility ratios of €23,331/QALY and €11,277/QALY for the guided and self-managed formats, respectively. A significant reduction in overall levels of menopausal symptoms or perceived impact of HF/NS resulted in incremental costs between €1460 and €1525 for the guided and €500–€753 for the self-managed format. The estimated annual budget impact for the Netherlands was €192,990 for the guided and €74,592 for the self-managed format.

Conclusion

Based on the current trial data, the results indicate that both guided and self-managed iCBT are cost-effective with a willingness-to-pay threshold of well below €30,000/QALY. Additionally, self-managed iCBT is the most cost-effective strategy and has a lower impact on healthcare budgets.

An Updated Systematic Review of Studies Mapping (or Cross-Walking) Measures of Health-Related Quality of Life to Generic Preference-Based Measures to Generate Utility Values

BACKGROUND

Mapping is an increasingly common method used to predict instrument-specific preference-based health-state utility values (HSUVs) from data obtained from another health-related quality of life (HRQoL) measure. There have been several methodological developments in this area since a previous review up to 2007.

OBJECTIVE

To provide an updated review of all mapping studies that map from HRQoL measures to target generic preference-based measures (EQ-5D measures, SF-6D, HUI measures, QWB, AQoL measures, 15D/16D/17D, CHU-9D) published from January 2007 to October 2018.

DATA SOURCES

A systematic review of English language articles using a variety of approaches: searching electronic and utilities databases, citation searching, targeted journal and website searches.

STUDY SELECTION

Full papers of studies that mapped from one health measure to a target preference-based measure using formal statistical regression techniques.

DATA EXTRACTION

Undertaken by four authors using predefined data fields including measures, data used, econometric models and assessment of predictive ability.

RESULTS

There were 180 papers with 233 mapping functions in total. Mapping functions were generated to obtain EQ-5D-3L/EQ-5D-5L-EQ-5D-Y (n = 147), SF-6D (n = 45), AQoL-4D/AQoL-8D (n = 12), HUI2/HUI3 (n = 13), 15D (n = 8) CHU-9D (n = 4) and QWB-SA (n = 4) HSUVs. A large number of different regression methods were used with ordinary least squares (OLS) still being the most common approach (used ≥ 75% times within each preference-based measure). The majority of studies assessed the predictive ability of the mapping functions using mean absolute or root mean squared errors (n = 192, 82%), but this was lower when considering errors across different categories of severity (n = 92, 39%) and plots of predictions (n = 120, 52%).

CONCLUSIONS

The last 10 years has seen a substantial increase in the number of mapping studies and some evidence of advancement in methods with consideration of models beyond OLS and greater reporting of predictive ability of mapping functions.

Self-Management education for adults with poorly controlled epILEpsy [SMILE (UK)]: a randomised controlled trial

BACKGROUND

Epilepsy is a common neurological condition resulting in recurrent seizures. Research evidence in long-term conditions suggests that patients benefit from self-management education and that this may improve quality of life (QoL). Epilepsy self-management education has yet to be tested in a UK setting.

OBJECTIVES

To determine the effectiveness and cost-effectiveness of Self-Management education for people with poorly controlled epILEpsy [SMILE (UK)].

DESIGN

A parallel pragmatic randomised controlled trial.

SETTING

Participants were recruited from eight hospitals in London and south-east England.

PARTICIPANTS

Adults aged ≥ 16 years with epilepsy and two or more epileptic seizures in the past year, who were currently being prescribed antiepileptic drugs.

INTERVENTION

A 2-day group self-management course alongside treatment as usual (TAU). The control group received TAU.

MAIN OUTCOME MEASURES

The primary outcome is QoL in people with epilepsy at 12-month follow-up using the Quality Of Life In Epilepsy 31-P (QOLIE-31-P) scale. Other outcomes were seizure control, impact of epilepsy, medication adverse effects, psychological distress, perceived stigma, self-mastery and medication adherence. Cost-effectiveness analyses and a process evaluation were undertaken.

RANDOMISATION

A 1 : 1 ratio between trial arms using fixed block sizes of two.

BLINDING

Participants were not blinded to their group allocation because of the nature of the study. Researchers involved in data collection and analysis remained blinded throughout.

RESULTS

The trial completed successfully. A total of 404 participants were enrolled in the study [SMILE (UK), n = 205; TAU, n = 199] with 331 completing the final follow-up at 12 months [SMILE (UK), n = 163; TAU, n = 168]. In the intervention group, 61.5% completed all sessions of the course. No adverse events were found to be related to the intervention. At baseline, participants had a mean age of 41.7 years [standard deviation (SD) 14.1 years], and had epilepsy for a median of 18 years. The mean QOLIE-31-P score for the whole group at baseline was 66.0 out of 100.0 (SD 14.2). Clinically relevant levels of anxiety symptoms were reported in 53.6% of the group and depression symptoms in 28.0%. The results following an intention-to-treat analysis showed no change in any measures at the 12-month follow-up [QOLIE-31-P: SMILE (UK) mean: 67.4, SD 13.5; TAU mean: 69.5, SD 14.8]. The cost-effectiveness study showed that SMILE (UK) was possibly cost-effective but was also associated with lower QoL. The process evaluation with 20 participants revealed that a group course increased confidence by sharing with others and improved self-management behaviours.

CONCLUSIONS

For people with epilepsy and persistent seizures, a 2-day self-management education course is cost-saving, but does not improve QoL after 12-months or reduce anxiety or depression symptoms. A psychological intervention may help with anxiety and depression. Interviewed participants reported attending a group course increased their confidence and helped them improve their self-management.

FUTURE WORK

More research is needed on self-management courses, with psychological components and integration with routine monitoring.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN57937389.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 21. See the NIHR Journals Library website for further project information.

Assessment of components included in published societal perspective or QALY outcome economic analyses for antiepileptic drug treatment in chronic epilepsy

INTRODUCTION

Antiepileptic drug (AED) treatments seek to control seizures with minimal or no adverse effects, effects which can substantially impact costs and outcomes for patients, caregivers, and third party payers. The First and Second Panel on Cost-Effectiveness in Health and Medicine recommend inclusion of a societal reference case, even in studies conducted from a healthcare sector perspective, for comparability of findings across studies. Cost and outcome evaluation components include direct medical, non-direct medical-related (e.g. patient-time and transportation costs for treatment) and non-healthcare sectors (e.g. lost productivity).

AREAS COVERED

Guided by Second Panel recommendations, this review developed an overall impact inventory and detailed adverse effect impact inventory to assess the scope and methods in published economic evaluations of AED treatments for adults with chronic epilepsy. Societal perspective evaluations or evaluations that utilized quality-adjusted life-years (QALYs) as an outcome were reviewed. The majority of reviewed articles were healthcare sector perspective studies, methods for estimating QALYs varied widely, and a minority considered specific AED treatment adverse effects.

EXPERT COMMENTARY

Only considering a healthcare sector perspective fails to provide full information for patients on AED treatments. Using an impact inventory to guide study scope and design will facilitate full reporting of costs and benefits.