Dependency and health utilities in stroke: Data to inform cost-effectiveness analyses

Cost-effectiveness of endovascular thrombectomy for acute ischemic stroke with established large infarct in Germany: a decision tree and Markov model

BACKGROUND

Recent studies, including the TENSION trial, support the use of endovascular thrombectomy (EVT) in acute ischemic stroke with large infarct (Alberta Stroke Program Early Computed Tomography Score (ASPECTS) 3-5).

OBJECTIVE

To evaluate the cost-effectiveness of EVT compared with best medical care (BMC) alone in this population from a German healthcare payer perspective.

METHODS

A short-term decision tree and a long-term Markov model (lifetime horizon) were used to compare healthcare costs and quality-adjusted life years (QALYs) between EVT and BMC. The effectiveness of EVT was reflected by the 90-day modified Rankin Scale (mRS) outcome from the TENSION trial. QALYs were based on published mRS-specific health utilities (EQ-5D-3L indices). Long-term healthcare costs were calculated based on insurance data. Costs (reported in 2022 euros) and QALYs were discounted by 3% annually. Cost-effectiveness was assessed using incremental cost-effectiveness ratios (ICERs). Deterministic and probabilistic sensitivity analyses were performed to account for parameter uncertainties.

RESULTS

Compared with BMC, EVT yielded higher lifetime incremental costs (€24 257) and effects (1.41 QALYs), resulting in an ICER of €17 158/QALY. The results were robust to parameter variation in sensitivity analyses (eg, 95% probability of cost-effectiveness was achieved at a willingness to pay of >€22 000/QALY). Subgroup analyses indicated that EVT was cost-effective for all ASPECTS subgroups.

CONCLUSIONS

EVT for acute ischemic stroke with established large infarct is likely to be cost-effective compared with BMC, assuming that an additional investment of €17 158/QALY is deemed acceptable by the healthcare payer.

Cost and Utility Estimates per Modified Rankin Scale Score up to 2 Years Post Stroke: Data to Inform Economic Evaluations From a Societal Perspective

OBJECTIVES

Model-based health economic evaluations of ischemic stroke are in need of cost- and utility estimates related to relevant outcome measures. This study aims to describe societal cost- and utility estimates per modified Rankin Scale (mRS)-score at different time points within 2 years post stroke.

METHODS

Included patients had a stroke between 3 months and 2.5 years ago. mRS and EQ-5D-5L were scored during a telephone interview. Based on the interview date, records were categorized into a time point: 3 months (3M; 3-6 months), 1 year (Y1; 6-18 months), or 2 years (Y2; 18-30 months). Patients completed a questionnaire on healthcare utilization and productivity losses in the previous 3 months. Initial stroke hospitalization costs were assessed. Mean costs and utilities per mRS and time point were derived with multiple imputation nested in bootstrapping. Cost at 3 months post stroke were estimated separately for endovascular treatment (EVT)-/non-EVT-patients.

RESULTS

1106 patients were included from 18 Dutch centers. At each time point, higher mRS-scores were associated with increasing average costs and decreasing average utility. Mean societal costs at 3M ranged from €11 943 (mRS 1, no EVT) to €55 957 (mRS 5, no EVT). For Y1, mean costs in the previous 3 months ranged from €885 (mRS 0) to €23 215 (mRS 5), and from €1655 (mRS 0) to €22 904 (mRS 5) for Y2. Mean utilities ranged from 0.07 to 0.96, depending on mRS and time point.

CONCLUSIONS

The mRS-score is a major determinant of costs and utilities at different post-stroke time points. Our estimates may be used to inform future model-based health economic evaluations.

Software with artificial intelligence-derived algorithms for analysing CT brain scans in people with a suspected acute stroke: a systematic review and cost-effectiveness analysis

Background

Artificial intelligence-derived software technologies have been developed that are intended to facilitate the review of computed tomography brain scans in patients with suspected stroke.

Objectives

To evaluate the clinical and cost-effectiveness of using artificial intelligence-derived software to support review of computed tomography brain scans in acute stroke in the National Health Service setting.

Methods

Twenty-five databases were searched to July 2021. The review process included measures to minimise error and bias. Results were summarised by research question, artificial intelligence-derived software technology and study type. The health economic analysis focused on the addition of artificial intelligence-derived software-assisted review of computed tomography angiography brain scans for guiding mechanical thrombectomy treatment decisions for people with an ischaemic stroke. The de novo model (developed in R Shiny, R Foundation for Statistical Computing, Vienna, Austria) consisted of a decision tree (short-term) and a state transition model (long-term) to calculate the mean expected costs and quality-adjusted life-years for people with ischaemic stroke and suspected large-vessel occlusion comparing artificial intelligence-derived software-assisted review to usual care.

Results

A total of 22 studies (30 publications) were included in the review; 18/22 studies concerned artificial intelligence-derived software for the interpretation of computed tomography angiography to detect large-vessel occlusion. No study evaluated an artificial intelligence-derived software technology used as specified in the inclusion criteria for this assessment. For artificial intelligence-derived software technology alone, sensitivity and specificity estimates for proximal anterior circulation large-vessel occlusion were 95.4% (95% confidence interval 92.7% to 97.1%) and 79.4% (95% confidence interval 75.8% to 82.6%) for Rapid (iSchemaView, Menlo Park, CA, USA) computed tomography angiography, 91.2% (95% confidence interval 77.0% to 97.0%) and 85.0 (95% confidence interval 64.0% to 94.8%) for Viz LVO (Viz.ai, Inc., San Fransisco, VA, USA) large-vessel occlusion, 83.8% (95% confidence interval 77.3% to 88.7%) and 95.7% (95% confidence interval 91.0% to 98.0%) for Brainomix (Brainomix Ltd, Oxford, UK) e-computed tomography angiography and 98.1% (95% confidence interval 94.5% to 99.3%) and 98.2% (95% confidence interval 95.5% to 99.3%) for Avicenna CINA (Avicenna AI, La Ciotat, France) large-vessel occlusion, based on one study each. These studies were not considered appropriate to inform cost-effectiveness modelling but formed the basis by which the accuracy of artificial intelligence plus human reader could be elicited by expert opinion. Probabilistic analyses based on the expert elicitation to inform the sensitivity of the diagnostic pathway indicated that the addition of artificial intelligence to detect large-vessel occlusion is potentially more effective (quality-adjusted life-year gain of 0.003), more costly (increased costs of £8.61) and cost-effective for willingness-to-pay thresholds of £3380 per quality-adjusted life-year and higher.

Limitations and conclusions

The available evidence is not suitable to determine the clinical effectiveness of using artificial intelligence-derived software to support the review of computed tomography brain scans in acute stroke. The economic analyses did not provide evidence to prefer the artificial intelligence-derived software strategy over current clinical practice. However, results indicated that if the addition of artificial intelligence-derived software-assisted review for guiding mechanical thrombectomy treatment decisions increased the sensitivity of the diagnostic pathway (i.e. reduced the proportion of undetected large-vessel occlusions), this may be considered cost-effective.

Future work

Large, preferably multicentre, studies are needed (for all artificial intelligence-derived software technologies) that evaluate these technologies as they would be implemented in clinical practice.

Study registration

This study is registered as PROSPERO CRD42021269609.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Evidence Synthesis programme (NIHR award ref: NIHR133836) and is published in full in Health Technology Assessment; Vol. 28, No. 11. See the NIHR Funding and Awards website for further award information.

International Systematic Review of Utility Values Associated with Cardiovascular Disease and Reflections on Selecting Evidence for a UK Decision-Analytic Model

PURPOSE

Evaluating interventions for cardiovascular disease (CVD) requires estimates of its effect on utility. We aimed to 1) systematically review utility estimates for CVDs published since 2013 and 2) critically appraise UK-relevant estimates and calculate corresponding baseline utility multipliers.

METHODS

We searched MEDLINE and Embase (April 22, 2021) using CVD and utility terms. We screened results for primary studies reporting utility distributions for people with experience of heart failure, myocardial infarction, peripheral arterial disease, stable angina, stroke, transient ischemic attack, or unstable angina. We extracted characteristics from studies included. For UK estimates based on the EuroQoL 5-dimension (EQ-5D) measure, we assessed risk of bias and applicability to a decision-analytic model, pooled arms/time points as appropriate, and estimated baseline utility multipliers using predicted utility for age- and sex- matched populations without CVD. We sought utility sources from directly applicable studies with low risk of bias, prioritizing plausibility of severity ordering in our base-case model and highest population ascertainment in a sensitivity analysis.

RESULTS

Most of the 403 studies identified used EQ-5D (n = 217) and most assessed Organisation for Economic Co-operation and Development populations (n = 262), although measures and countries varied widely. UK studies using EQ-5D (n = 29) produced very heterogeneous baseline utility multipliers for each type of CVD, precluding meta-analysis and implying different possible severity orderings. We could find sources that provided a plausible ordering of utilities while adequately representing health states.

CONCLUSIONS

We cataloged international CVD utility estimates and calculated UK-relevant baseline utility multipliers. Modelers should consider unreported sources of heterogeneity, such as population differences, when selecting utility evidence from reviews.

HIGHLIGHTS

Published systematic reviews have summarized estimates of utility associated with cardiovascular disease published up to 2013.We 1) reviewed utility estimates for 7 types of cardiovascular disease published since 2013, 2) critically appraised UK-relevant studies, and 3) estimated the effect of each cardiovascular disease on baseline utility.Our review 1) recommends a consistent and reliable set of baseline utility multipliers for 7 types of cardiovascular disease and 2) provides systematically identified reference information for researchers seeking utility evidence for their own context.

Cost-utility of direct transfer to angiography suite (DTAS) bypassing conventional imaging for patients with acute ischemic stroke in Spain: results from the ANGIOCAT trial

BACKGROUND

The ANGIOCAT trial showed a clinical benefit of direct to angiography suite (DTAS) for patients with large vessel occlusion (LVO) stroke admitted within 6 hours after symptom onset in decreased hospital workflow time and improved clinical outcome. However, the impact of DTAS implementation on hospital costs is unknown. This economic evaluation aims to assess the cost-utility of DTAS from the provider (hospital) perspective.

METHODS

A cost-utility analysis was applied to compare DTAS with the standard direct to CT (DTCT) suite approach using direct cost and health outcomes data. The time horizon was 90 days. One-way sensitivity analysis as well as probabilistic sensitivity analysis was performed, varying the model parameters by ±25%. Measures included costs, quality-adjusted life years, and incremental cost-effectiveness ratios. Health outcomes, classified according to the modified Rankin Scale, were obtained from the ANGIOCAT trial. Respective utilities were obtained from the literature.

RESULTS

DTAS is the dominant strategy. The incremental cost-effectiveness ratio is -€89 110 (-$97 600) with cost saving per patient of -€2848 (-$3120). The improved clinical outcome is directly related with a decrease in costs for the hospital, mainly due to the decrease in costs of hospital stay, improved clinical outcome and fewer complications.

CONCLUSIONS

For patients with LVO admitted within 6 hours after symptom onset, the DTAS not only improves clinical outcome but also decreases the costs (dominant option) compared with the standard DTCT. Multicentric international randomized clinical trials are ongoing to determine the replicability of our findings.

A systematic review and meta-analysis of health utility values among patients with ischemic stroke

Purpose

Ischemic stroke (IS) has a considerable impact on the health-related quality of life (HRQoL) of patients. A systematic review was conducted to summarize and synthesize the HRQoL reported from IS patients.

Methods

An electronic search was performed in PubMed, Web of Science, ScienceDirect, Embase, and Cochrane Library databases from inception to February 2022 for studies measuring utility values in IS patients. Basic information about the studies, patient characteristics, measurement of the utility values, and utility values were extracted and summarized. Utility values were pooled according to the time of evaluation, and disease severity was classified with modified Rankin Scale (mRS) scores. The quality of the studies was assessed according to key criteria recommended by the National Institute for Health and Care Excellence.

Results

A total of 39 studies comprising 30,853 participants were included in the study. Measured with EQ-5D-3L, the pooled utility values were 0.42 [95% confidential interval (CI): 0.13 to 0.71], 0.55 (95% CI: 0.43 to 0.68), 0.65 (95% CI: 0.52 to 0.78), 0.60 (95% CI: 0.43 to 0.78), and 0.67 (95% CI: 0.60 to 0.74) for patients diagnosed with IS within 1, 3, 6, 12, and 24 months or above among poststroke patients. Four studies reported utility values classified by mRS scores where synthesized estimates stratified by mRS scores ranged from 0.91 (95% CI: 0.85 to 0.97) for patients with an mRS score of 1 to-0.04 (95% CI:-0.18 to 0.11) for those with an mRS score of 5. As for the health dimension profiles, usual activity was the most impacted dimension, while self-care was the least impacted one.

Conclusion

This study indicated that the utility values in IS patients kept increasing from stroke onset and became relatively stabilized at 6 months poststroke. Health utility values decreased significantly as mRS scores increased. These results facilitate economic evaluations in utility retrieval and selection. Further exploration was required regarding the factors that affect the HRQoL of IS patients.

Cost-effectiveness of tenecteplase versus alteplase for acute ischemic stroke

INTRODUCTION

Alteplase is widely used as an intravenous thrombolytic drug in acute ischemic stroke (AIS). Recently however, tenecteplase, a modified form of tissue plasminogen activator, has been shown to increase early recanalization rate and has proven to be non-inferior with a similar safety profile compared to alteplase. This study aims to evaluate the cost-effectiveness of 0.25 mg/kg tenecteplase versus 0.9 mg/kg alteplase for intravenous thrombolysis in AIS patients from the Dutch healthcare payer perspective.

METHODS

A Markov decision-analytic model was constructed to assess total costs, total quality-adjusted life year (QALY), an incremental cost-effectiveness ratio, and incremental net monetary benefit (INMB) of two treatments at willingness-to-pay (WTP) thresholds of €50,000/QALY and €80,000/QALY over a 10-year time horizon. One-way sensitivity analysis, probabilistic sensitivity analysis, and scenario analysis were conducted to test the robustness of results. Clinical data were obtained from large randomized controlled trials and real-world data.

RESULTS

Treatment with tenecteplase saved €21 per patient while gaining 0.05 QALYs, resulting in INMB of €2381, clearly rendering tenecteplase cost-effective compared to alteplase. Importantly, tenecteplase remained the cost-effective alternative in all scenarios, including AIS patients due to large vessel occlusion (LVO). Probabilistic sensitivity analysis proved tenecteplase to be cost-effective with a 71.0% probability at a WTP threshold of €50,000/QALY.

CONCLUSIONS

Tenecteplase treatment was cost-effective for all AIS patients (including AIS patients with LVO) compared to alteplase. The finding supports the broader use of tenecteplase in acute stroke care, as health outcomes improve at acceptable costs while having practical advantages, and a similar safety profile.

Cost-benefit analysis of stroke rehabilitation in Iran

BACKGROUND

The economic evaluation of medication interventions for stroke has been the subject of much economic research. This study aimed to examine the cost-benefit of multidisciplinary rehabilitation services for stroke survivors in Iran.

METHODS

This economic evaluation was conducted from the payer's perspective with a lifetime horizon in Iran. A Markov model was designed and Quality-adjusted life years (QALYs) were the final outcomes. First, to evaluate the cost-effectiveness, the incremental cost-effectiveness ratio (ICER) was calculated. Then, using the average net monetary benefit (NMB) of rehabilitation, the average Incremental Net Monetary Benefit (INMB) per patient was calculated. The analyses were carried out separately for public and private sector tariffs.

RESULTS

While considering public tariffs, the rehabilitation strategy had lower costs (US$5320 vs. US$ 6047) and higher QALYs (2.78 vs. 2.61) compared to non-rehabilitation. Regarding the private tariffs, the rehabilitation strategy had slightly higher costs (US$6,698 vs. US$6,182) but higher QALYs (2.78 vs. 2.61) compared to no rehabilitation. The average INMB of rehabilitation vs non-rehabilitation for each patient was estimated at US$1518 and US$275 based on Public and private tariffs, respectively.

CONCLUSION

Providing multidisciplinary rehabilitation services to stroke patients was cost-effective and has positive INMBs in public and private tariffs.

The preventable productivity burden of sleep apnea in Australia: a lifetime modelling study

Obstructive sleep apnea (OSA) is a common disorder. OSA is associated with cardiovascular disease (CVD), type 2 diabetes mellitus (T2DM) and depression, among other comorbidities. We aim to determine the productivity burden of OSA in Australia using productivity-adjusted life-years (PALYs). Using life table modelling, we built a multistate Markov model to estimate the impact of moderate to severe OSA on the whole working-age Australian population in 2021 (aged 20-65 years) with OSA until retirement (aged 66 years). The model also captured the impact of OSA on CVD, T2DM, depression, and vehicle-related accidents. Data for OSA and comorbidities and Australian specific labour data, were extracted from published sources. A second cohort was then modelled to test the effect of a hypothetical intervention, assuming a 10% reduction in OSA prevalence and a 10% reduction in comorbidities in patients with OSA. The primary outcome of interest were PALYs accrued. All outcomes were discounted 5% annually. Over a lifetime, the Australian population with OSA accrued 193,713,441 years of life lived and 182,737,644 PALYs. A reduction of 10% in OSA prevalence and comorbidities would result in 45,401 extra years of life lived and 150,950 extra PALYs. This resulted in more than AU$25 billion of gained gross domestic product over the lifetime of the working population. Our study highlights the substantial burden of OSA on the Australian population and the need to tailor interventions at the population level to reduce the health and economic impacts.

Cost-Effectiveness of SAPIEN 3 Transcatheter Aortic Valve Implantation Versus Surgical Aortic Valve Replacement in German Severe Aortic Stenosis Patients at Low Surgical Mortality Risk

INTRODUCTION

In the randomized PARTNER 3 trial, transcatheter aortic valve implantation (TAVI) with the SAPIEN 3 device significantly reduced a composite of all-cause death, stroke, and rehospitalization, compared with surgical aortic valve replacement (SAVR), in patients with severe symptomatic aortic stenosis and low risk of surgical mortality. Furthermore, TAVI has been shown to be cost-effective in low-risk patients, compared with SAVR, in a number of countries. This study aimed to determine the cost-effectiveness of TAVI with SAPIEN 3 versus SAVR in Germany.

METHODS

A previously published two-stage Markov-based model that captured clinical outcomes from the PARTNER 3 trial was adapted for the German context using the German Statutory Health Insurance perspective. The model had a lifetime horizon. The cost-utility analysis estimated changes in direct healthcare costs as well as survival and health-related quality of life using TAVI with SAPIEN 3 compared with SAVR.

RESULTS

TAVI with SAPIEN 3 increased quality-adjusted life years (QALYs) by + 0.72 at an increased cost of €8664 per patient. The incremental cost-effectiveness/QALY ratio was €12,037, which fell below that of other cardiovascular interventions in use in Germany. The cost-effectiveness of TAVI over SAVR remained robust across multiple challenging scenarios and was driven by lower longer-term management costs compared with SAVR.

CONCLUSIONS

TAVI with SAPIEN 3 appears to be a clinically meaningful, cost-effective treatment option over SAVR for patients with severe symptomatic aortic stenosis and low risk for surgical mortality in Germany.

CLINICAL TRIAL REGISTRATION NUMBER

www.

CLINICALTRIALS

gov identifier: NCT02675114.

Cost-effectiveness of rhythm control strategy: Ablation versus antiarrhythmic drugs for treating atrial fibrillation in Korea based on real-world data

Background

Ablation-based treatment has emerged as an alternative rhythm control strategy for symptomatic atrial fibrillation (AF). Recent studies have demonstrated the cost-effectiveness of ablation compared with medical therapy in various circumstances. We assessed the economic comparison between ablation and medical therapy based on a nationwide real-world population.

Methods and findings

For 192,345 patients with new-onset AF (age ≥ 18 years) identified between August 2015 and July 2018 from the Korean Health Insurance Review and Assessment Service (HIRA) database, medical resource use data were collected to compare AF patients that underwent ablation (N = 2,131) and those administered antiarrhythmic drugs (N = 8,048). Subsequently, a Markov chain Monte Carlo model was built. The patients had at least one risk factor for stroke, and the base-case used a 20-year time horizon, discounting at 4.5% annually. Transition probabilities and costs were estimated using the present data, and utilities were derived from literature review. The costs were converted to US $ (2019). Sensitivity analyses were performed using probabilistic and deterministic methods. The net costs and quality-adjusted life years (QALY) for antiarrhythmic drugs and ablation treatments were $37,421 and 8.8 QALYs and $39,820 and 9.3 QALYs, respectively. Compared with antiarrhythmic drugs, incremental cost-effectiveness ratio of ablation was $4,739/QALY, which is lower than the willingness-to-pay (WTP) threshold of $32,000/QALY.

Conclusion

In symptomatic AF patients with a stroke risk under the age of 75 years, ablation-based rhythm control is potentially a more economically attractive option compared with antiarrhythmic drug-based rhythm control in Korea.

Conceptual Framework for Optimised Proxy Value Set Selection Through Supra-National Value Set Development for the EQ-5D Instruments

BACKGROUND

Preference differences between countries and populations justify the use of country-specific value sets for the EQ-5D instruments. There are no clear criteria based on which the selection of value sets for countries without a national value set should be made. As part of the European PECUNIA project, this study aimed to identify factors contributing to differences in preference-based valuations and develop supra-national value sets for homogenous country clusters in Europe.

METHODS

A literature review was conducted to identify factors relevant to variations in the EQ-5D-3L/5L health state valuations across countries. Factors fulfilling the pre-specified criteria of validity, reliability, international feasibility and comparability were used to group 27 European Union member states, the European Free Trade Association countries and the UK. Clusters of countries were developed based on the frequency of their appearance in the same grouping. The supra-national value sets were estimated for these clusters from the coefficients of existing published valuation studies using the ordinary least-squares model.

RESULTS

Ten factors were identified from 69 studies. From these, five grouping variables: (1) culture and religion; (2) linguistics; (3) healthcare system typology; (4) healthcare system financing; and (5) sociodemographic aspects were derived to define the groups of homogenous countries. Frequency-based grouping revealed five cohesive clusters: English-speaking, Nordic, Central-Western, Southern and Eastern European.

CONCLUSIONS

European countries were clustered considering variables that may relate to differences in health state valuations. Supra-national value sets provide optimised proxy value set selection in the lack of a national value set and/or for regional decision making.

Cost-Effectiveness of Cilostazol Added to Aspirin or Clopidogrel for Secondary Prevention After Noncardioembolic Stroke

Background The objective of the study was to assess the cost-effectiveness of cilostazol (a selective phosphodiesterase 3 inhibitor) added to aspirin or clopidogrel for secondary stroke prevention in patients with noncardioembolic stroke. Methods and Results A Markov model decision tree was used to examine lifetime costs and quality-adjusted life years (QALYs) of patients with noncardioembolic stroke treated with either aspirin or clopidogrel or with additional cilostazol 100 mg twice daily. Cohorts were followed until all patients died from competing risks or ischemic or hemorrhagic stroke. Probabilistic sensitivity analysis using Monte Carlo simulation was used to model 10 000 cohorts of 10 000 patients. The addition of cilostazol to aspirin or clopidogrel is strongly cost saving. In all 10 000 simulations, the cilostazol strategy resulted in lower health care costs compared with aspirin or clopidogrel alone (mean $13 488 cost savings per patient; SD, $8087) and resulted in higher QALYs (mean, 0.585 more QALYs per patient lifetime; SD, 0.290). This result remained robust across a variety of sensitivity analyses, varying cost inputs, and treatment effects. At a willingness-to-pay threshold of $50 000/QALY, average net monetary benefit from the addition of cilostazol was $42 743 per patient over their lifetime. Conclusions Based on the best available data, the addition of cilostazol to aspirin or clopidogrel for secondary prevention following noncardioembolic stroke results in significantly reduced health care costs and a gain in lifetime QALYs.

Cost-Utility Analysis of Dabigatran and Warfarin for Stroke Prevention Among Patients With Nonvalvular Atrial Fibrillation in India

OBJECTIVES

Dabigatran has a better safety profile and requires less monitoring, but is costlier than warfarin. This study evaluated the cost-utility of dabigatran relative to warfarin for preventing stroke in nonvalvular atrial fibrillation (NVAF) in India.

METHODS

A Markov decision analysis model was developed to compare dabigatran (110 or 150 mg twice a day) to warfarin titrated to target prothrombin time in patients with NVAF at high risk of stroke. Model utilities and transition probabilities were based on literature and costs on market prices. Data on out-of-pocket expenses and income lost were taken from a nationally representative survey. We adopted a societal perspective and discounted both costs and outcomes at 3%. Ischemic stroke, intracranial bleed, other major bleeds, and death were outcomes of NVAF. The model projected the costs, life-years, and quality-adjusted life-years (QALYs) for each intervention over a lifetime. We used gross domestic product per capita of India (US dollars [US$]1889) as the cost-effectiveness threshold. Sensitivity analyses were conducted.

RESULTS

Treatment with either dose of dabigatran was associated with gain in life-years and QALYs compared with warfarin. The discounted incremental cost-effectiveness ratios/QALYs for both doses of dabigatran (110 mg US$7519; 150 mg US$6634) were above the cost-effectiveness threshold, and the probability of being cost-effective at this threshold was low. Cost of dabigatran was an important factor in determining incremental cost-effectiveness ratio. Price reduction of 150 mg dose by 49% will make it cost-effective.

CONCLUSIONS

Dabigatran is not cost-effective in the Indian societal context. Reducing the price of dabigatran 150 mg by half will make it cost-effective.

Projected New-Onset Cardiovascular Disease by Socioeconomic Group in Australia

BACKGROUND

Socioeconomic status has an important effect on cardiovascular disease (CVD). Data on the economic implications of CVD by socioeconomic status are needed to inform healthcare planning.

OBJECTIVES

The aim of this study was to project new-onset CVD and related health economic outcomes in Australia by socioeconomic status from 2021 to 2030.

METHODS

A dynamic population model was built to project annual new-onset CVD by socioeconomic quintile in Australians aged 40-79 years from 2021 to 2030. Cardiovascular risk was estimated using the Pooled Cohort Equation (PCE) from Australian-specific data, stratified for each socioeconomic quintile. The model projected years of life lived, quality- adjusted life-years (QALYs), acute healthcare medical costs, and productivity losses due to new-onset CVD. All outcomes were discounted by 5% annually.

RESULTS

PCE estimates showed that 8.4% of people in the most disadvantaged quintile were at high risk of CVD, compared with 3.7% in the least disadvantaged quintile (p < 0.001). From 2021 to 2030, the model projected 32% more cardiovascular events in the most disadvantaged quintile compared with the least disadvantaged (127,070 in SE 1 vs. 96,222 in SE 5). Acute healthcare costs in the most disadvantaged quintile were Australian dollars (AU$) 183 million higher than the least disadvantaged, and the difference in productivity costs was AU$959 million. Removing the equity gap (by applying the cardiovascular risk from the least disadvantaged quintile to the whole population) would prevent 114,822 cardiovascular events and save AU$704 million of healthcare costs and AU$3844 million of lost earnings over the next 10 years.

CONCLUSION

Our results highlight the pressing need to implement primary prevention interventions to reduce cardiovascular health inequity. This model provides a platform to incorporate socioeconomic status into health economic models by estimating which interventions are likely to yield more benefits in each socioeconomic quintile.

Quality of life and cost consequence of delays in endovascular treatment for acute ischemic stroke in China

BACKGROUND

Although endovascular therapy (EVT) improves clinical outcomes in patients with acute ischemic stroke, the time of EVT initiation significantly influences clinical outcomes and healthcare costs. This study evaluated the impact of EVT treatment delay on cost-effectiveness in China.

METHODS

A model combining a short-term decision tree and long-term Markov health state transition matrix was constructed. For each time window of symptom onset to EVT, the probability of receiving EVT or non-EVT treatment was varied, thereby varying clinical outcomes and healthcare costs. Clinical outcomes and cost data were derived from clinical trials and literature. Incremental cost-effectiveness ratio and incremental net monetary benefits were simulated. Deterministic and probabilistic sensitivity analyses were performed to assess the robustness of the model. The willingness-to-pay threshold per quality-adjusted life-year (QALY) was set to ¥71,000 ($10,281).

RESULTS

EVT performed between 61 and 120 min after the stroke onset was most cost-effective comparing to other time windows to perform EVT among AIS patients in China, with an ICER of ¥16,409/QALY ($2376) for performing EVT at 61-120 min versus the time window of 301-360 min. Each hour delay in EVT resulted in an average loss of 0.45 QALYs and 165.02 healthy days, with an average net monetary loss of ¥15,105 ($2187).

CONCLUSIONS

Earlier treatment of acute ischemic stroke patients with EVT in China increases lifetime QALYs and the economic value of care without any net increase in lifetime costs. Thus, healthcare policies should aim to improve efficiency of pre-hospital and in-hospital workflow processes to reduce the onset-to-puncture duration in China.

Cost-effectiveness of andexanet alfa versus four-factor prothrombin complex concentrate for the treatment of oral factor Xa inhibitor-related intracranial hemorrhage in the US

AIM

To conduct a cost-effectiveness analysis (CEA) on the use of andexanet alfa for the treatment of factor Xa inhibitor-related intracranial hemorrhage (ICH) from the US third-party payer and societal perspectives.

METHODS

CEA compared andexanet alfa to prothrombin complex concentrate for the treatment of patients receiving factor Xa inhibitors admitted to hospital inpatient care with an ICH. The model comprised two linked phases. Phase 1 utilized a decision tree to model the acute treatment phase (admission of a patient with ICH into intensive care for the first 30 days). Phase 2 modeled long-term costs and outcomes using three linked Markov models comprising the six health states defined by the modified Rankin score.

RESULTS

The analysis showed that the strategy of using andexanet alfa for the treatment of factor Xa inhibitor-related ICH is cost-effective, with incremental cost-effectiveness per quality-adjusted life-year gained of $35,872 from a third-party payer perspective and $40,997 from a societal perspective over 20 years.

LIMITATIONS

(1) Absence of head-to-head trials comparing therapies included in the economic model, (2) lack of comparative long-term data on treatment efficacy, and (3) bias resulting from the study designs of published literature.

CONCLUSION

Given these results, the use of andexanet alfa for the reversal of anticoagulation in patients with factor Xa inhibitor-related ICH may improve quality of life and is likely to be cost-effective in a US context.

Cost-effectiveness analysis in patients with an unruptured cerebral aneurysm treated with observation or surgery

OBJECTIVE

The main goal of preventive treatment of unruptured intracranial aneurysms (UIAs) is to avoid the morbidity and mortality associated with aneurysmal subarachnoid hemorrhage. A comparison between the conservative approach and the surgical approach combining endovascular treatment and microsurgical clipping is currently lacking. This study aimed to conduct an updated evaluation of cost-effectiveness comparing the two approaches in patients with UIA.

METHODS

A decision tree with a Markov model was developed. Quality-adjusted life-years (QALYs) associated with living with UIA before and after treatment were prospectively collected from a cohort of patients with UIA at a tertiary center. Other inputs were obtained from published literature. Using Monte Carlo simulation for patients aged 55, 65, and 75 years, the authors modeled the conservative management in comparison with preventive treatment. Different proportions of endovascular and microsurgical treatment were modeled to reflect existing practice variations between treatment centers. Outcomes were assessed in terms of QALYs. Sensitivity analyses to assess the model's robustness and completed threshold analyses to examine the influence of input parameters were performed.

RESULTS

Preventive treatment of UIAs consistently led to higher utility. Models using a higher proportion of endovascular therapy were more cost-effective. Models with older cohorts were less cost-effective than those with younger cohorts. Treatment was cost-effective (willingness to pay < 100,000 USD/QALY) if the annual rupture risk exceeded a threshold between 0.8% and 1.9% in various models based on the proportion of endovascular treatment and cohort age. A higher proportion of endovascular treatments and younger age lowered this threshold, making the treatment of aneurysms with a lower risk of rupture more cost-effective.

CONCLUSIONS

Preventive treatment of aneurysms led to higher utility compared with conservative management. Models with a higher proportion of endovascular treatment and younger patient age were most cost-effective.

Cost-Effectiveness of Magnetic Resonance Imaging-Guided Thrombolysis for Patients With Stroke With Unknown Time of Onset

OBJECTIVES

Patients waking up with stroke symptoms are often excluded from intravenous thrombolysis with alteplase (IV-tpa). The WAKE-UP trial, a European multicenter randomized controlled trial, proved the clinical effectiveness of magnetic resonance imaging-guided IV-tpa for these patients. This analysis aimed to assess the cost-effectiveness of the intervention compared to placebo.

METHODS

A Markov model was designed to analyze the cost-effectiveness over a 25-year time horizon. The model consisted of an inpatient acute care phase and a rest-of-life phase. Health states were defined by the modified Rankin Scale (mRS). Initial transition probabilities to mRS scores were based on WAKE-UP data and health state utilities on literature search. Costs were based on data from the University Medical Center Hamburg-Eppendorf, literature, and expert opinion. Incremental costs and effects over the patients' lifetime were estimated. The analysis was conducted from a formal German healthcare perspective. Univariate and probabilistic sensitivity analyses were performed.

RESULTS

Treatment with IV-tpa resulted in cost savings of €51 009 and 1.30 incremental gains in quality-adjusted life-years at a 5% discount rate. Univariate sensitivity analysis revealed incremental cost-effectiveness ratio being sensitive to the relative risk of favorable outcome on mRS for placebo patients after stroke, the costs of long-term care for patients with mRS 4, and patient age at initial stroke event. In all cases, IV-tpa remained cost-effective. Probabilistic sensitivity analysis proved IV-tpa cost-effective in >95% of the simulations results.

CONCLUSIONS

Magnetic resonance imaging-guided IV-tpa compared to placebo is cost-effective in patients with ischemic stroke with unknown time of onset.

Breathing Synchronised Hypoglossal Nerve Stimulation with Inspire for Untreated Severe Obstructive Sleep Apnoea/Hypopnoea Syndrome: A Simulated Cost-Utility Analysis from a National Health Service Perspective

BACKGROUND

Hypoglossal nerve stimulation (HNS) with Inspire is a novel treatment indicated for moderate or severe obstructive sleep apnoea/hypopnoea syndrome (OSAHS), intolerant to or unable to be treated with continuous positive airway pressure (CPAP).

OBJECTIVE

The aim of this study was to assess the cost effectiveness of treating moderate or severe OSAHS, in patients intolerant to CPAP, with HNS, compared with standard care, from a National Health Service (NHS) perspective.

METHODS

A cohort state transition model was developed to compare HNS with Inspire with no treatment in UK adult patients with moderate or severe OSAHS who have previously tried and have not responded to CPAP therapy. Published literature was applied in the model to estimate incremental cost-effectiveness ratios (ICERs; 2019 Great British pounds per quality-adjusted life-year [QALY] gained), from an NHS and personal social services (PSS) perspective, over a cohort's lifetime.

RESULTS

The model base-case predicts that patients undergoing HNS will incur lifetime costs of £65,026 compared with £36,727 among untreated patients. The HNS cohort would gain 12.72 QALYs compared with 11.15 QALYs in the no-treatment arm. The ICER of treating severe OSAHS with HNS is therefore estimated to be £17,989 per QALYs gained. Probabilistic sensitivity analysis found that at a threshold of £30,000/QALY, HNS has a 69% probability of being cost effective. Limitations of the model include uncertainty around the utility data that were not sourced directly from HNS clinical trials. There is further uncertainty in the relationship between change in the Apnoea-Hypopnoea Index (AHI) and reduction in ischaemic heart disease and stroke because of difficulty capturing the reduction in risk over a long time horizon in studies.

CONCLUSIONS

Over a patient's lifetime, HNS with Inspire is expected to be cost effective when compared with no treatment in patients with severe OSAHS who have tried and have not responded to CPAP, from an NHS perspective.

From Three-Months to Five-Years: Sustaining Long-Term Benefits of Endovascular Therapy for Ischemic Stroke

Background and Purpose: During the months and years post-stroke, treatment benefits from endovascular therapy (EVT) may be magnified by disability-related differences in morbidity/mortality or may be eroded by recurrent strokes and non-stroke-related disability/mortality. Understanding the extent to which EVT benefits may be sustained at 5 years, and the factors influencing this outcome, may help us better promote the sustenance of EVT benefits until 5 years post-stroke and beyond.

Methods: In this review, undertaken 5 years after EVT became the standard of care, we searched PubMed and EMBASE to examine the current state of the literature on 5-year post-stroke outcomes, with particular attention to modifiable factors that influence outcomes between 3 months and 5 years post-EVT.

Results: Prospective cohorts and follow-up data from EVT trials indicate that 3-month EVT benefits will likely translate into lower 5-year disability, mortality, institutionalization, and care costs and higher quality of life. However, these group-level data by no means guarantee maintenance of 3-month benefits for individual patients. We identify factors and associated “action items” for stroke teams/systems at three specific levels (medical care, individual psychosocioeconomic, and larger societal/environmental levels) that influence the long-term EVT outcome of a patient. Medical action items include optimizing stroke rehabilitation, clinical follow-up, secondary stroke prevention, infection prevention/control, and post-stroke depression care. Psychosocioeconomic aspects include addressing access to primary care, specialist clinics, and rehabilitation; affordability of healthy lifestyle choices and preventative therapies; and optimization of family/social support and return-to-work options. High-level societal efforts include improving accessibility of public/private spaces and transportation, empowering/engaging persons with disability in society, and investing in treatments/technologies to mitigate consequences of post-stroke disability.

Conclusions: In the longtime horizon from 3 months to 5 years, several factors in the medical and societal spheres could negate EVT benefits. However, many factors can be leveraged to preserve or magnify treatment benefits, with opportunities to share responsibility with widening circles of care around the patient.

Cost Burden and Cost-Effective Analysis of the Nationwide Implementation of the Quality in Acute Stroke Care Protocol in Australia

OBJECTIVES

The Quality in Acute Stroke Care (QASC) protocol is a multidisciplinary approach to implement evidence-based treatment after acute stroke that reduces death and disability. This study sought to evaluate the cost-effectiveness of implementing the QASC protocol across Australia, from a healthcare and a societal perspective.

MATERIALS AND METHODS

A decision-analytic model was constructed to reflect one-year outcomes post-stroke, aligned with the stroke severity categories of the modified Rankin scale (mRS). Decision analysis compared outcomes following implementation of the QASC protocol versus no implementation. Population data were extracted from Australian databases and data inputs regarding stroke incidence, costs, and utilities were drawn from published sources. The analysis assumed a progressive uptake and efficacy of the QASC protocol over five years. Health benefits and costs were discounted by 5% annually. The cost of each year lived by an Australian, from a societal perspective, was based on the Australian Government's 'value of statistical life year' (AUD 213,000).

RESULTS

Over five years, the model predicted 263,722 strokes among the Australian population. The implementation of the QASC protocol was predicted to prevent 1,154 deaths and yield a gain of 876 years of life (0.003 per stroke), and 3,180 quality-adjusted life years (QALYs) (0.012 per stroke). There was an estimated net saving of AUD 65.2 million in healthcare costs (AUD 247 per stroke) and AUD 251.7 million in societal costs (AUD 955 per stroke).

CONCLUSIONS

Implementation of the QASC protocol in Australia represents both a dominant (cost-saving) strategy, from a healthcare and a societal perspective.

Challenges of Outcome Prediction for Acute Stroke Treatment Decisions

Physicians often base their decisions to offer acute stroke therapies to patients around the question of whether the patient will benefit from treatment. This has led to a plethora of attempts at accurate outcome prediction for acute ischemic stroke treatment, which have evolved in complexity over the years. In theory, physicians could eventually use such models to make a prediction about the treatment outcome for a given patient by plugging in a combination of demographic, clinical, laboratory, and imaging variables. In this article, we highlight the importance of considering the limits and nuances of outcome prediction models and their applicability in the clinical setting. From the clinical perspective of decision-making about acute treatment, we argue that it is important to consider 4 main questions about a given prediction model: (1) what outcome is being predicted, (2) what patients contributed to the model, (3) what variables are in the model (considering their quantifiability, knowability at the time of decision-making, and modifiability), and (4) what is the intended purpose of the model? We discuss relevant aspects of these questions, accompanied by clinically relevant examples. By acknowledging the limits of outcome prediction for acute stroke therapies, we can incorporate them into our decision-making more meaningfully, critically examining their contents, outcomes, and intentions before heeding their predictions. By rigorously identifying and optimizing modifiable variables in such models, we can be empowered rather than paralyzed by them.

Future burden of cardiovascular disease in Australia: impact on health and economic outcomes between 2020 and 2029

AIMS

To estimate the health and economic burden of new and established cardiovascular disease from 2020 to 2029 in Australia.

METHODS AND RESULTS

A two-stage multistate dynamic model was developed to predict the burden of the incident and prevalent cardiovascular disease, for Australians 40-90 years old from 2020 to 2029. The model captured morbidity, mortality, years of life lived, quality-adjusted life years, healthcare costs, and productivity losses. Cardiovascular risk for the primary prevention population was derived using Australian demographic data and the Pooled Cohort Equation. Risk for the secondary prevention population was derived from the REACH registry. Input data for costs and utilities were extracted from published sources. All outcomes were annually discounted by 5%. A number of sensitivity analyses were undertaken to test the robustness of the study. Between 2020 and 2029, the model estimates 377 754 fatal and 991 375 non-fatal cardiovascular events. By 2029, 1 061 756 Australians will have prevalent cardiovascular disease (CVD). The population accrued 8 815 271 [95% uncertainty interval (UI) 8 805 083-8 841 432] years of life lived with CVD and 5 876 975 (5 551 484-6 226 045) QALYs. The total healthcare costs of CVD were projected to exceed Australian dollars (AUD) 61.89 (61.79-88.66) billion, and productivity losses will account for AUD 78.75 (49.40-295.25) billion, driving the total cost to surpass AUD 140.65 (123.13-370.23) billion.

CONCLUSION

Cardiovascular disease in Australia has substantial impacts in terms of morbidity, mortality, and lost revenue to the healthcare system and the society. Our modelling provides important information for decision making in relation to the future burden of cardiovascular disease.

Cost-effectiveness of antithrombotic agents for atrial fibrillation in older adults at risk for falls: a mathematical modelling study

BACKGROUND

Antithrombotic drugs decrease stroke risk in patients with atrial fibrillation, but they increase bleeding risk, particularly in older adults at high risk for falls. We aimed to determine the most cost-effective antithrombotic therapy in older adults with atrial fibrillation who are at high risk for falls.

METHODS

We conducted a mathematical modelling study from July 2019 to March 2020 based on the Ontario, Canada, health care system. We derived the base-case age, sex and fall risk distribution from a published cohort of older adults at risk for falls, and the bleeding and stroke risk parameters from an atrial fibrillation trial population. Using a probabilistic microsimulation Markov decision model, we calculated quality-adjusted life years (QALYs), total cost and incremental cost-effectiveness ratios (ICERs) for each of acetylsalicylic acid (ASA), warfarin, apixaban, dabigatran, rivaroxaban and edoxaban. Cost data were adjusted for inflation to 2018 values. The analysis used the Ontario public payer perspective with a lifetime horizon.

RESULTS

In our model, the most cost-effective antithrombotic therapy for atrial fibrillation in older patients at risk for falls was apixaban, with an ICER of $8517 per QALY gained (5.86 QALYs at $92 056) over ASA. It was a dominant strategy over warfarin and the other antithrombotic agents. There was moderate uncertainty in cost-effectiveness ranking, with apixaban as the preferred choice in 66% of model iterations (given willingness to pay of $50 000 per QALY gained); edoxaban, 30 mg, was preferred in 31% of iterations. Sensitivity analysis across ranges of age, bleeding risk and fall risk still favoured apixaban over the other medications.

INTERPRETATION

From a public payer perspective, apixaban is the most cost-effective antithrombotic agent in older adults at high risk for falls. Health care funders should implement strategies to encourage use of the most cost-effective medication in this population.

Lifetime quality of life and cost consequences of delays in endovascular treatment for acute ischaemic stroke: a cost-effectiveness analysis from a Singapore healthcare perspective

OBJECTIVES

Endovascular therapy (EVT) significantly improves clinical outcomes in patients with acute ischaemic stroke (AIS), while the time of EVT initiation after stroke onset influences both patient clinical outcomes and healthcare costs. This study determined the impact of EVT treatment delay on cost effectiveness of EVT in the Singapore healthcare setting.

DESIGN

A short-term decision tree and long-term Markov health state transition model was constructed. For each time window of symptom onset to EVT, the probability of receiving EVT or non-EVT treatment was varied, thereby varying clinical outcomes (modified Rankin Scale scores), short-term costs and long-term modelled (lifetime) costs; all of which were used in calculating an incremental cost-effectiveness ratio of EVT vs non-EVT treatment. Clinical outcomes and cost data were derived from clinical trials, literature, expert opinion, electronic medical records and community-based surveys from Singapore. Deterministic one-way and probabilistic sensitivity analyses were performed to assess the uncertainty of the model. The willingness to pay for per quality-adjusted life-year (QALY) was set to Singapore $50 000 (US$36 500).

SETTING

Singapore healthcare perspective.

PARTICIPANTS

The model included patients with AIS in Singapore.

INTERVENTIONS

EVT performed within 6 hours of stroke onset.

OUTCOME MEASURES

The model estimated incremental cost-effectiveness ratios (ICERs) and net monetary benefits (NMB) for EVT versus non-EVT treatment, varied by time from symptom onset to time of treatment.

RESULTS

EVT performed between 61 min and 120 min after the stroke onset was most cost-effective time window to perform EVT in the Singapore population, with an ICER of Singapore $7197 per QALY (US$5254) for performing EVT at 61-120 min versus 121-180 min. The resulting incremental NMB associated with receipt of EVT at the earlier time point is Singapore $39 827 (US$29 074) per patient at the willingness-to-pay threshold of Singapore $50 000. Each hour delay in EVT resulted in an average loss of 0.54 QALYs and 195.35 healthy days, with an average net monetary loss of Singapore $26 255 (US$19 166).

CONCLUSIONS

From the Singapore healthcare perspective, although EVT is more expensive than alternative treatments in the short term, the lifetime ICER is below the willingness-to-pay threshold. Thus, healthcare policies and procedures should aim to improve efficiency of pre-hospital and in-hospital workflow processes to reduce the onset-to-puncture duration.

Utility-Weighted Modified Rankin Scale Scores for the Assessment of Stroke Outcome: Pooled Analysis of 20 000+ Patients

BACKGROUND AND PURPOSE

Patient-centered care prioritizes patient beliefs and values towards wellbeing. We aimed to map functional status (modified Rankin Scale [mRS] scores) and health-related quality of life on the European Quality of Life 5-dimensional questionnaire (EQ-5D) to derive utility-weighted (UW) stroke outcome measures and test their statistical properties and construct validity.

METHODS

UW-mRS scores were derived using linear regression, with mRS as a discrete ordinal explanatory response variable in 8 large international acute stroke trials. Linear regression models were used to validate UW-mRS scores by assessing differences in mean UW-mRS scores between the treatment groups of each trial. To explore the variability in EQ-5D between individual mRS categories, we generated receiver operator characteristic curves for EQ-5D to differentiate between sequential mRS categories and misclassification matrix to classify individual patients into a matched mRS category based on the closest UW-mRS value to their observed individual EQ-5D value.

RESULTS

Among 22 946 acute stroke patients, derived UW-mRS across mRS scores 0 to 6 were 0.96, 0.83, 0.72, 0.54, 0.22, -0.18, and 0, respectively. Both UW-mRS and ordinal mRS scores captured divergent treatment effects across all 8 acute stroke trials. The sample sizes required to detect the treatment effects using UW-mRS scores as a continuous variable were almost half that required in trials for a binary cut point on the mRS. Area under receiver operator characteristic curves based on EQ-5D utility values varied from 0.66 to 0.81. Misclassification matrix showed moderate agreement between actual and matched mRS scores (kappa, 0.68 [95% CI, 0.67-0.68]).

CONCLUSIONS

Medical strategies that target avoiding dependency may provide maximum benefit in terms of poststroke health-related quality of life. Despite variable differences with mRS scores, the UW-mRS provides efficiency gains as a smaller sample size is required to detect a treatment effect in acute stroke trials through use of continuous scores. Registration: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT00226096, NCT00716079, NCT01422616, NCT02162017, NCT00120003, NCT02123875. URL: http://ctri.nic.in; Unique identifier: CTRI/2013/04/003557. URL: https://www.isrctn.com; Unique identifier: ISRCTN89712435.

Weights for ordinal analyses of the modified Rankin Scale in stroke trials: A population-based cohort study

BACKGROUND

Ordinal/shift analyses of ordered measures like the modified Rankin Scale(mRS) are underused as primary trial outcomes for neurological disorders - despite statistical advantages - potentially hindered by poor clinical interpretability versus dichotomies, and by valuing state-transitions equally (linear scale). Weighted ordinal analyses incorporating step-changes at key transitions might have greater statistical validity and clinical applicability.

METHODS

In a prospective population-based cohort of ischaemic stroke (Oxford Vascular Study, recruited 2002-2014), we stratified 5-year outcomes of death, dementia, and/or institutionalization, health/social-care costs, and EuroQol-derived quality-adjusted life-expectancy(QALE) by 3-month mRS. We compared root-mean-square errors(RMSEs) from linear regressions for these outcomes with the mRS coded as a linear scale versus incorporating a spline at transitions 1-2, 2-3, or 3-4. We derived 3-month mRS weights for probability of 5-year death/dementia/institutionalization using age/sex-adjusted logistic regressions, and cost and QALE weights from 1000-bootstraps. We applied these weights to analyse recent trials of thrombectomy for acute ischaemic stroke.

FINDINGS

Among 1,607 patients, a non-linear (S-shaped) relationship was observed between 3-month mRS and each 5-year outcome, with RMSEs 18-73% lower using a spline at mRS 2-3 versus a linear representation. Age/sex-adjusted probability weights for 5-year death/dementia/institutionalization were: mRS 0=0.19; 1=0.27; 2=0.41; 3=0.73; 4=0.77; 5=0.94 (mRS 6=1 by definition). Similar trends were seen with costs; estimated 5-year QALEs were: mRS 0=3.88; 1=3.49; 2=3.01; 3=1.87; 4=1.30; 5=0.06; 6=0. Results were similar stratifying by age/sex, and excluding pre-morbidly disabled patients. Using a weighted ordinal approach, estimates of thrombectomy impact were more favourable than estimates with dichotomous approaches, 5-year cost reductions being 29% higher than with 0-2/3-6, and over three-fold higher than with 0-1/2-6 dichotomy.

INTERPRETATION

Our findings favour weighting the mRS in ordinal analyses for stroke and other neurological disorders, as state-transitions differ in clinical prognosis, quality-of-life, and costs. These weights could also be used for prognostication and cost-effectiveness analyses.

FUNDING

Wellcome Trust, Wolfson Foundation, NIHR Oxford Biomedical Research Centre, Rhodes Trust.

Health Utility Weighting of the Modified Rankin Scale: A Systematic Review and Meta-analysis

IMPORTANCE

The utility-weighted modified Rankin Scale (UW-mRS) has been proposed as a patient-centered alternative primary outcome for stroke clinical trials. However, to date, there is no clear consensus on an approach to weighting the mRS.

OBJECTIVE

To characterize the between-study variability in utility weighting of the mRS in a population of patients who experienced stroke and its implications when applied to the results of a clinical trial.

DATA SOURCES

In this systematic review and meta-analysis, MEDLINE, Embase, and PsycINFO were searched from January 1987 through May 2019 using major search terms for stroke, health utility, and mRS.

STUDY SELECTION

Original research articles published in English were reviewed. Included were studies with participants 18 years or older with ischemic or hemorrhagic stroke, transient ischemic attack, or subarachnoid hemorrhage, with mRS scores and utility weights evaluated concurrently. A total of 5725 unique articles were identified. Of these, 283 met criteria for full-text review, and 24 were included in the meta-analysis.

DATA EXTRACTION AND SYNTHESIS

PRISMA guidelines for systematic review were followed. Data extraction was performed independently by multiple researchers. Data were pooled using mixed models.

MAIN OUTCOMES AND MEASURES

The mean utility weights and 95% CIs were calculated for each mRS score and health utility scale. Geographic differences in weighting for the EuroQoL 5-dimension (EQ-5D) and Stroke Impact Scale-based UW-mRS were explored using inverse variance-weighted linear models. The results of 18 major acute stroke trials cited in current guidelines were then reanalyzed using the UW-mRS weighting scales identified in the systematic review.

RESULTS

The meta-analysis included 22 389 individuals; the mean (SD) age of participants was 65.9 (4.0) years, and the mean (SD) proportion of male participants was 58.2% (7.5%). For all health utility scales evaluated, statistically significant differences were observed between the mean utility weights by mRS score. For studies using an EQ-5D-weighted mRS, between-study variance was higher for worse (mRS 2-5) compared with better (mRS 0-1) scores. Of the 18 major acute stroke trials with reanalyzed results, 3 had an unstable outcome when using different UW-mRSs.

CONCLUSIONS AND RELEVANCE

Multiple factors, including cohort-specific characteristics and health utility scale selection, can influence mRS utility weighting. If the UW-mRS is selected as a primary outcome, the approach to weighting may alter the results of a clinical trial. Researchers using the UW-mRS should prospectively and concurrently obtain mRS scores and utility weights to characterize study-specific outcomes.

Yet another Ersatz World: The ICER Final Evidence Report for Additive Cardiovascular Therapies

Previous commentaries in the Formulary Evaluation section of INNOVATIONS in Pharmacy have pointed to the lack of credibility in modeled claims for cost-effectiveness and associated recommendations for pricing by the Institute for Clinical and Economic Review (ICER). The principal objection to ICER reports has been that their modeled claims fail the standards of normal science: they are best seen as pseudoscience. The purpose of this latest commentary is to consider the recently released ICER report for Additive Cardiovascular Disease therapies. This report should not be taken seriously in its claims for cost-effectiveness and pricing in cardiovascular disease (CVD). The analytical framework applied by ICER fails to meet the standards of normal science in demarcating science from pseudoscience. Irrespective of the value judgements and recommendations of an ICER report, these lack credibility. They were never intended to be evaluable and replicable across treatment settings. The claims made are constructed, driven by assumption, and should be put to one side by health system decision makers. In this review the focus is on to the ICER modeled estimates of utility scores in CVD, the insistence on utilizing a generic utility algorithm (the EQ-5D-3L) and the consequent quality adjusted life year (QALY) estimates. Two issues are raised that will be the subject of future commentaries: the lack of appreciation of fundamental measurement and (ii) the importance of the patient voice in benefit claims. Given the importance in the ICER methodology of QALYS, the ad hoc nature of the ordinal utilities introduced to the cardiovascular model must raise concerns over the role the ICER evidence report may play in health care decision-making. These concerns extend to the claim by ICER that, on ICER's own affordability threshold for individual new molecular entities, the anticipated uptake of these therapies may raise questions of overall affordability. Again, we are dealing with an arbitraryconstruct that may adversely impact patient access.

Direct Assessment of Health Utilities Using the Standard Gamble Among Patients With Primary Intracerebral Hemorrhage

BACKGROUND

Standard gamble (SG) directly measures patients' valuation of their health state. We compare in-hospital and day-90 SG utilities (SGU) among intracerebral hemorrhage patients and report a 3-way association between SGU, EuroQoL-5 dimension, and modified Rankin Scale at day 90.

METHODS AND RESULTS

Patients with intracerebral hemorrhage underwent in-hospital and day-90 assessments for the modified Rankin Scale, EuroQoL-5 dimension, and SG. SG provides patients a choice between their current health state and a hypothetical treatment with varying chances of either perfect health or a painless death. Higher SGU (scale, 0-1) indicates lower risk tolerance and thus higher valuation of the current health state. Logistic regression was used to estimate the likelihood of low SGU (≤0.6), and Wilcoxon paired signed-rank test compared in-hospital and day-90 SGU. In-hospital and day-90 SG was obtained from 381 and 280 patients, respectively, including 236 paired observations. Median (interquartile range) in-hospital and day-90 SGUs were 0.85 (0.40-0.98) and 0.98 (0.75-1.00; P<0.001). In-hospital SGUs were lower with advancing age (P=0.007), higher National Institutes of Health Stroke Scale, and intracerebral hemorrhage scores (P<0.001). Proxy-based assessments resulted in lower SGUs; median difference (95% CI), -0.2 (-0.33 to -0.07). After adjustment, higher National Institutes of Health Stroke Scale and proxy assessments were independently associated with lower SGU, along with an effect modification of age by race. Day-90 SGU and modified Rankin Scale were significantly correlated; however, SGUs were higher than the EuroQoL-5 dimension utilities at higher modified Rankin Scale levels.

CONCLUSIONS

Divergence between directly (SGU) and indirectly (EuroQoL-5 dimension) assessed utilities at high levels of functional disability warrant careful prognostication of intracerebral hemorrhage outcomes and should be considered in designing early end-of-life care discussions with families and patients.

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.

Measuring functional limitations after venous thromboembolism: A call to action

The main objectives of therapeutic trials in venous thromboembolism (VTE) are to prevent recurrent VTE, major bleeding and death. While these outcomes are indeed highly relevant, they are also rare and do not fully capture the overall functional outcome of VTE patients. Importantly, functional limitations after VTE are prevalent after both deep vein thrombosis and pulmonary embolism occurring in up to 50% of patients. These post-VTE syndromes are associated with a decreased quality of life, higher risk of depressive disorders, unemployment and increased utilization of healthcare resources. Because of the major impact of functional limitations on individual patients and society as a whole, development of tools able to capture functional outcomes in clinical trials are urgently needed. We anticipate that a standardized post-VTE functional status scale will aid in demarcating effective and ineffective VTE therapies on functional outcomes in trials with appropriately powered sample sizes, as well as pave the road for value-based healthcare. The scale that we have in mind covers the entire spectrum of functional outcomes ranging from no symptoms to death. Moreover, it focuses on both limitations in usual activity as well as changes in lifestyle. The scale is not meant to replace current diagnostic or prognostic scores for post-VTE syndromes, but to be used as an outcome measure to evaluate the overall consequences of VTE on functional status. This review is a call for action to the VTE community to join forces and support further development of the proposed scale, a process of which we summarize the necessary steps.

Utility-weighted modified Rankin Scale: Still too crude to be a truly patient-centric primary outcome measure?

BACKGROUND

The utility-weighted modified Rankin Scale (UW-mRS) is an outcome measure recently proposed to improve statistical efficiency and interpretability of the mRS. Statistical properties of the UW-mRS have been well investigated, but construct validity has yet to be established.

AIMS

To investigate the construct validity of the UW-mRS as a primary outcome measure by assessing variability in utility values within and between mRS categories, over time post-stroke, and by different derivation methods.

METHODS

UW-mRS was derived using assessment of quality of life (AQoL-4D) and mRS scores at 3 and 12 months (n = 2030) from a large randomized controlled trial, A Very Early Rehabilitation Trial (AVERT). Receiver operator characteristic (ROC) analysis of AQoL-4D was conducted to differentiate between sequential mRS categories. Intraclass correlation was used to explore variability in utility values over time post-stroke, UW-mRS values, and derivation methods from multiple studies.

RESULTS

UW-mRS values for mRS categories 0-6 at three months were 0.80, 0.78, 0.63, 0.37, 0.11, 0.03, and 0. Based on AQoL-4D utility values, areas under the ROC curve varied from 0.54 to 0.87. Time post-stroke explained 42%-56% of variability in AQoL-4D utility values in patients with no change in mRS between 3 and 12 months. The choice of the derivation method contributed to 25% of the variability in UW-mRS values.

CONCLUSIONS

The high variability in utility values between and within mRS categories, over time post-stroke, and using different derivation methods is not adequately reflected in the UW-mRS. These threats to construct validity warrant caution when using UW-mRS as a primary outcome measure.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN12606000185561).

The combined impact of dependency on caregivers, disability, and coping strategy on quality of life after ischemic stroke

BACKGROUND

To estimate the additional impact of coping and of being dependent on caregivers, over and above the large effects of disability on utility after ischemic stroke.

METHODS

A total of 539 patients were recruited into an observational, retrospective study when returning for a check-up between 3 and 36 months after an ischemic stroke. Patients' modified Rankin Scale (mRS), dependency on caregivers, the Brandtstädter and Renner Coping questionnaire (with summary scores: Tenacity of Goal Pursuit (TGP) and Flexible Goal Adjustment (FGA) coping styles), EQ-5D-3 L and co-morbidities were evaluated.

RESULTS

In multivariable regression, greater disability (mRS) resulted in large utility losses, between 0.06 for mRS 1 to 0.65 for mRS 5 (p < 0.0001). Dependency on caregivers caused an additional dis-utility of 0.104 (p = 0.0006) which varied by mRS (0.044, 0.060, 0.083, 0.115, 0.150 and 0.173 for mRS 0-5). The effect of coping on utility varied by coping style, by the disability level of the patient and by his or her dependency on caregivers. FGA coping was associated with additional increases in utility (p < 0.0001) over and above the effect of disability and dependency, whereas TGA had no significant impact. FGA coping was associated with larger utility changes among more disabled patients (0.018 to 0.105 additional utility, for mRS 0 to mRS 5 respectively). Dependent patients had more to gain from FGA coping than patients who function independently of caregivers: utility gains were between 0.049 and 0.072 for moderate to high levels of FGA coping. In contrast, the same positive evolution in FGA coping resulted in 0.039 and 0.057 utility gain among independent patients. Finally, we found that important stroke risk factors and co-morbidities, such as diabetes and atrial fibrillation, were not predictors of EQ-5D utility in a multivariable setting.

CONCLUSIONS

This study suggests that treatment strategies targeting flexible coping styles and decreasing dependency on caregivers may lead to significant gains in quality of life above and beyond treatment strategies that solely target disability.

Estimating costs and health outcomes of publicly funded tick-born encephalitis vaccination: A cost-effectiveness analysis

BACKGROUND

The number of notified cases of Tick-Borne Encephalitis (TBE) in Sweden has been increasing the past years despite the increased use of TBE-vaccine not subsidized by the healthcare system. Stockholm County is a high endemic area and an earlier study has shown that low-income households have lower vaccination coverage even when they are at high risk. This paper aims to determine the cost-effectiveness of a publicly funded TBE vaccination program in Stockholm.

METHODS

In three different cohorts with individuals aged 3, 40 or 50 years, long-term costs and health outcomes of an out-of-pocket strategy (53% of the cohort is vaccinated on their own expenses) and a structured vaccination program (full cohort is vaccinated covered by the publicly funded health care system), were estimated using a Markov model. The Markov model predicts the costs and effects in term of Quality-adjusted Life Years (QALYs) over a lifetime horizon using a third-party healthcare payer perspective. The primary results are presented as an incremental cost effectiveness ratio (ICER) indicating the additional cost required to achieve one additional QALY with the structured vaccination program.

RESULTS

The results show that the structured vaccination program is associated with a gain in QALYs and increased costs compared with an out-of-pocket strategy. The calculated ICERs were 27 761, 99 527 and 160 827 SEK/QALY in cohorts of age 3, 40 and 50, respectively. The sensitivity analyses showed that the results are robust when varying different parameters.

CONCLUSION

Given the setting of Stockholm county, this analysis shows a cost per QALY of a free vaccinations program, especially for children of 3 years old, below generally acceptable cost-effectiveness thresholds in Sweden.

Functional Assessment for Acute Stroke Trials: Properties, Analysis, and Application

A measure of treatment effect is needed to assess the utility of any novel intervention in acute stroke. For a potentially disabling condition such as stroke, outcomes of interest should include some measure of functional recovery. There are many functional outcome assessments that can be used after stroke. In this narrative review, we discuss exemplars of assessments that describe impairment, activity, participation, and quality of life. We will consider the psychometric properties of assessment scales in the context of stroke trials, focusing on validity, reliability, responsiveness, and feasibility. We will consider approaches to the analysis of functional outcome measures, including novel statistical approaches. Finally, we will discuss how advances in audiovisual and information technology could further improve outcome assessment in trials.