State Transition Model Research Articles

Development and validation of a chronic kidney disease progression model using patient-level simulations

Chronic disease progression models are available for several highly prevalent conditions. For chronic kidney disease (CKD), the scope of existing progression models is limited to the risk of kidney failure and major cardiovascular (CV) events. The aim of this project was to develop a comprehensive CKD progression model (CKD-PM) that simulates the risk of CKD progression and a broad range of complications in patients with CKD. A series of literature reviews informed the selection of risk factors and identified existing risk equations/algorithms for kidney replacement therapy (KRT), CV events, other CKD-related complications, and mortality. Risk equations and transition probabilities were primarily sourced from publications produced by large US and international CKD registries. A patient-level, state-transition model was developed with health states defined by the Kidney Disease Improving Global Outcomes categories. Model validation was performed by comparing predicted outcomes with observed outcomes in the source cohorts used in model development (internal validation) and other cohorts (external validation). The CKD-PM demonstrated satisfactory modeling properties. Accurate prediction of all-cause and CV mortality was achieved without calibration, while prediction of CV events through CKD-specific equations required implementation of a calibration factor to balance time-dependent versus baseline risk. Predicted annual changes in estimated glomerular filtration rate (eGFR) and urine albumin-creatinine ratio were acceptable in comparison to external values. A flexible eGFR threshold for KRT equations enabled accurate prediction of these events. This CKD-PM demonstrated reliable modeling properties. Both internal and external validation revealed robust outcomes.

Improving Health Outcomes Through Treatment Sequencing Optimization in Multiple Myeloma: A Simulation Model in Transplant-Ineligible Patients.

Patients with multiple myeloma often require multiple treatment lines. The order in which treatments are sequenced has impact on clinical outcomes. This study aimed to estimate progression-free survival (PFS) and overall survival (OS) with common treatment sequences used in Portugal and the incremental benefit of an optimal sequence in transplant-ineligible patients with multiple myeloma. A state-transition sequential model with a five-health state conceptual structure was developed to simulate and compare survival outcomes between treatment sequences up to four lines of treatments. Data sources included randomized clinical trials and indirect treatment comparisons. A panel of Portuguese hematologists listed four most common treatment sequences and optimal sequence of choice in transplant-ineligible patients. Our simulation estimated an OS between 6.1 and 7.8 years using the most common sequences, with VMP + DRd + Pd + Kd as the most effective (7.8 years). Optimal sequence of choice (DRd + PVd + Kd + Vd) achieved OS of 9.8 years and may extend OS in 2.0-3.7 years vs. most common sequences (26%-61% increase). This benefit was mostly explained by extended PFS in the first line of treatment. Model results demonstrate that choosing the most effective treatment upfront is crucial in delaying disease progression thus yielding better survival outcomes in transplant-ineligible patients. There was a clear survival benefit in using daratumumab-based regimens in first line. This modelling exercise highlights the need to raise awareness around the impact of sequencing strategies to improve patient's outcomes.

Long-Term Health Outcomes of Huntington Disease and the Impact of Future Disease-Modifying Treatments: A Decision-Modeling Analysis.

Disease-modifying treatments (DMTs) such as gene therapy are currently under investigation as a potential treatment for Huntington disease (HD). Our objective was to estimate the long-term natural history of HD progression and explore the potential efficacy impacts and value of a hypothetical DMT using a decision-analytic modeling framework. We developed a health state transition model that separately analyzed 40-year-old individuals with prefunctional decline (PFD, HD Integrated Staging System [HD-ISS] stage <3, total functional score [TFC] 13), active functional decline Shoulson and Fahn category 1 (SF1, HD-ISS stage 3, TFC 13-11), and SF2 (HD-ISS stage 3, TFC 10-7). Three-year outcomes from the TRACK-HD longitudinal study were linearly extrapolated to estimate the long-term health outcomes and costs of each population. For PFD individuals, we used the HD-ISS to predict the onset of functional decline. HD costs and quality-adjusted life years (QALYs) were estimated over a lifetime horizon by applying health state-specific costs and utilities derived from a related HD burden-of-illness study. We then estimated the long-term health impacts of hypothetical DMTs that slowed or delayed onset of functional decline. We conducted sensitivity analyses to assess model uncertainties. The expected life years for 40-year-old PFD, SF1, and SF2 populations were 20.46 (95% credible range [CR]: 19.05-22.30), 13.93 (10.82-19.08), and 10.99 (8.28-22.07), respectively. The expected QALYs for PFD, SF1, and SF2 populations were 15.93 (14.91-17.44), 8.29 (6.36-11.79), and 5.79 (4.14-12.91), respectively. The lifetime costs of HD were $508,200 ($310,300 to $803,700) for the PFD population, $1.15 million ($684,500 to $1.89 million) for SF1 individuals, and $1.07 million ($571,700 to $2.26 million) for SF2 individuals. Although hypothetical DMTs led to cost savings in the PFD population by delaying the cost burdens of functional decline, they increased costs in SF1 and SF2 populations by prolonging time spent in expensive progressive HD states. Our novel HD-modeling framework estimates HD progression over a lifetime and the associated costs and QALYs. Our approach can be used for future cost-effectiveness models as positive DMT clinical trial evidence becomes available.

Cost-effectiveness analysis of microwave ablation versus robot-assisted partial nephrectomy for patients with small renal masses in Australia

ObjectivesMicrowave ablation (MWA) has gained attention as a minimally invasive and safe alternative to surgical intervention for patients with small renal masses; however, its cost-effectiveness in Australia remains unclear. This study conducted a cost-effectiveness analysis to evaluate the relative clinical and economic merits of MWA compared to robotic-assisted partial nephrectomy (RA-PN) in the treatment of small renal masses. MethodsA Markov state-transition model was constructed to simulate the progression of Australian patients with small renal masses treated with MWA versus RA-PN over a 10-year horizon. Transition probabilities and utility data were sourced from comprehensive literature reviews, and cost data were estimated from the Australian health system perspective. Life-years, quality-adjusted life-years (QALYs), and lifetime costs were estimated. Modelled uncertainty was assessed using both deterministic and probabilistic sensitivity analyses. A willingness-to-pay (WTP) threshold of $50,000 per QALY was adopted. All costs are expressed in 2022 Australian dollars and discounted at 3% annually. To assess the broader applicability of our findings, a validated cost-adaptation method was employed to extend the analysis to 8 other high-income countries. ResultsBoth the base case and cost-adaptation analyses revealed that MWA dominated RA-PN, producing both lower costs and greater effectiveness over 10 years. The cost-effectiveness outcome was robust across all model parameters. Probabilistic sensitivity analyses confirmed that MWA was dominant in 98.3% of simulations at the designated WTP threshold, underscoring the reliability of the model under varying assumptions. ConclusionFor patients with small renal masses in Australia and comparable healthcare settings, MWA is the preferred strategy to maximize health benefits per dollar, making it a highly cost-effective alternative to RA-PN.

Cost-effectiveness of sodium-glucose cotransporter-2 inhibitors in the treatment of diabetic nephropathy in Japan.

To assess the cost-effectiveness of diabetic nephropathy treatment with sodium-glucose cotransporter-2 (SGLT2) inhibitors in Japanese clinical practice, considering diabetes-related complications. A population-based Monte Carlo simulation was used to estimate the cost-effectiveness for people with diabetic nephropathy who initiated pharmacotherapy with an SGLT2 inhibitor plus conventional treatment or conventional treatment alone, based on quality-adjusted life-years (QALYs) and healthcare costs. The Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation study (CREDENCE) and the Japanese Society for Dialysis Research statistical survey were the primary sources of probability and mortality, while Japanese Health Insurance Claims Data were the cost source. The state transition model included diabetic nephropathy, hospitalization due to cardiovascular disease, dialysis, and death. One-way and probabilistic sensitivity analyses were used to explore model uncertainty. Using the threshold of JPY 5 000 000 per QALY, SGLT2 inhibitor plus conventional treatment was more cost-effective than conventional treatment alone, with an incremental cost-effectiveness ratio of JPY 654 309 per QALY. Treating 100 000 people, SGLT2 inhibitor plus conventional treatment prevented 2234 deaths and reduced 5793 fewer heart failure cases, 3967 fewer myocardial infarctions and stroke events. Sensitivity analysis affirmed the robustness of these results for patients aged under 70 years. The SGLT2 inhibitor treatment appeared to be cost-effective for the overall population of our study and particularly for younger patients (<70 years old). For older patients (≥70 years old), the cost-effectiveness was less clear and may require further evaluation. Decision-makers should consider this age-based heterogeneity when making recommendations about SGLT2 inhibitor treatment.

Genicular Artery Embolization, Radiofrequency Ablation, and Corticosteroid Therapy for Knee Osteoarthritis: A Cost-Effectiveness Analysis Using Randomized Clinical Trial Data.

Background: Many patients with symptomatic knee osteoarthritis (KOA) are refractory to traditional nonsurgical treatments such as intraarticular corticosteroid (CS) injection but are not yet eligible for or decline surgery. Genicular artery embolization (GAE) and radiofrequency ablation (RFA) are emerging adjunctive or alternative minimally invasive treatments. Objective: To perform a cost-effectiveness analysis (CEA) comparing CS, GAE, and RFA, for treatment of symptomatic KOA using a Markov model based on a de novo network meta-analysis (NMA) of randomized control trials. Methods: CEA was conducted to compare GAE and RFA to CS using a Markov cohort state-transition model from a U.S. Medicare payer's perspective over a 4-year time horizon. The model incorporated each treatment's success and attrition rates, costs, and utility benefit. Utility benefit values were derived at short-term (0.5-3 months) and long-term (6-12 months) posttreatment follow-up from NMA of published RCTs using an outcome of improved knee pain and/or function. Analyses were conducted at a willingness-to-pay threshold of $100,000 per quality-adjusted life year (QALY). Sensitivity analyses were performed, including when simulating various cost setting scenarios (i.e., office vs hospital outpatient treatment). Results: RFA demonstrated larger treatment effect than GAE, more pronounced at short-term [standardized mean difference (SMD), -1.6688, 95% CI [-2.7806; -0.5571], p=.003] than long-term (SMD -0.3822, 95% CI [-1.9743; 1.2100], p=.64) follow-up. Across cost setting scenarios, incremental cost-effectiveness ratios relative to CS were $561-1563/QALY for GAE versus $76-429/QALY for RFA (not counting scenarios in which RFA was dominated by CS). GAE demonstrated higher cost-effectiveness probability compared to RFA (41.6-54.8% vs. 18.4-29.2%, respectively). GAE was more cost-effective than RFA when the GAE clinical success rate and post-GAE utility value exceeded 32.1-51.0% and 0.562-0.617, respectively, and when the GAE quarterly attrition rate was less than 8.8-17.4%. RFA was more cost-effective when baseline pre-treatment utility values exceeded 0.695-0.713. Neither GAE costs nor RFA costs were sensitive parameters. Conclusion: Across scenarios, GAE was consistently the most likely cost-effective treatment option compared to RFA and CS, although clinical success rates, attrition rates, and utility values impact its cost-effectiveness. Clinical Impact: GAE is likely to be more cost-effective than RFA or CS for treatment of symptomatic KOA.

Destination and time-series inference of moving objects via conditionally Markov process

AbstractThis paper presents a destination and time-series inference algorithm for tracking moving targets. The destination of the object is considered the intent, and inference and state estimation are performed in the Bayesian framework. To describe the destination-aware target motion, we construct the state transition model using a conditionally Markov process. We introduce a multiple model to achieve simultaneous intent and time-series inferences. Given finite destination candidates, the maximum a posteriori hypothesis is chosen as the destination. For time-series inference, local estimates obtained from Kalman filters are fused to yield target state estimates. To address unspecified terminal conditions, the proposed algorithm incorporates parameter correction techniques based on relative geometry. Numerical simulations are performed to validate the proposed inference algorithm.

Estimating the Economically Justifiable Price of Limited-Duration Treatment with Donanemab for Early Symptomatic Alzheimer's Disease in the United States.

The goal of this economic model is to estimate an economically justifiable price (EJP) for using donanemab for the treatment of early symptomatic Alzheimer's disease (AD) in the United States based on clinical data from the phase 3 TRAILBLAZER-ALZ 2 trial (NCT04437511). We adapted an AD Markov state-transition model developed by the Institute for Clinical and Economic Review to estimate the EJP for donanemab at different willingness-to-pay (WTP) thresholds from the health care system perspective and the societal perspective as co-base cases. Assuming a WTP threshold of $150,000 per quality-adjusted life-year (QALY) gained, the model estimates a 1-year (13-dose) EJP for donanemab of $80,538 from the health care system perspective and $91,126 from the societal perspective; at a WTP threshold of $100,000 per QALY gained, the model estimates a 1-year (13-dose) EJP for donanemab of $44,691 from the health care system perspective and $55,419 from the societal perspective. Mean total treatment costs per patient at the $150,000 per QALY gained EJP derived from the health care system perspective were estimated at $77,812 based on the average number of doses of donanemab patients received in the co-base case analysis. One-way sensitivity analysis (OWSA) indicated that treatment efficacy, disease severity at the time of treatment initiation, and duration of treatment effect were the main drivers of the potential EJP. Results from this modeling simulation informed by the TRAILBLAZER-ALZ 2 study support an EJP for limited-duration treatment with donanemab that exceeds per-dose list prices for currently available amyloid-targeting therapies, implying potentially lower lifetime costs and better value for money.

Cost-effectiveness analysis of tislelizumab plus chemotherapy versus standard chemotherapy in first-line treatment for extensive-stage small cell lung cancer: perspectives from the United States and China.

Tislelizumab combined with chemotherapy has shown significant clinical benefits in improving overall survival compared to chemotherapy alone for patients with extensive-stage small-cell lung cancer (ES-SCLC). This study aimed to evaluate the cost-effectiveness of tislelizumab plus chemotherapy versus standard chemotherapy as a first-line treatment for ES-SCLC from the US payer perspective and the perspective of the Chinese healthcare system. We conducted an economic evaluation using a Markov state-transition model, reflecting the US payer perspective and the perspective of the Chinese healthcare system. Baseline patient characteristics and essential clinical data were obtained from the RATIONALE-312 trial. The costs and utilities were derived from open-access databases and published literature. The primary outcomes measured included quality-adjusted life years (QALYs), incremental cost-effectiveness ratio (ICER), incremental net health benefit (INHB), and incremental net monetary benefit (INMB). Uncertainties in the model were addressed by probabilistic sensitivity analysis (PSA) and one-way sensitivity analysis (OWSA). In the base-case analysis, the addition of tislelizumab to chemotherapy provided an incremental gain of 0.16 QALYs at an additional cost of $7430.73, resulting in an ICER of $46,132.33 per QALY. Although above the willingness-to-pay (WTP) threshold of China of $38,042.49 per QALY, the cost-effectiveness was marginal, with an INHB of - 0.03 QALYs and an INMB of $- 1303.06. In the US, despite a slightly higher effectiveness gain of 0.28 QALYs, the increased cost of $45,157.35 resulted in an unfavorable ICER of $163,885.06 per QALY, exceeding the US WTP threshold of $150,000.00. PSA showed probabilities of cost-effectiveness of tislelizumab plus chemotherapy at 17.18% in China and 40.41% in the US. Tislelizumab combined with chemotherapy was not a cost-effective first-line treatment option for ES-SCLC in China or the US; however, the margin of cost-effectiveness was narrow.

The conceptualisation of cardiometabolic disease policy model in the UK

BackgroundDecision models are increasingly used to inform policy-making processes, and there is a need to improve their credibility. The estimation of health and economic outcomes generated from decision models is influenced by the development process itself. This paper aims to present the conceptual model development process of cardiometabolic disease (CMD) policy models in the UK setting.MethodsThis conceptual model followed the International Society of Pharmacoeconomics and Outcomes Research-Society of Medical Decision Making (ISPOR-SMDM) Modelling Good Research Practices Task Force-2.ResultsFirst, for the conceptualisation of the problem, the CMD disease staging, progression and current clinical guidelines were summarised, followed by a systematic review of published policy models. We critically appraised policy models such as cardiovascular disease and type 2 diabetes. Key messages from the review emphasised the importance of understanding various determinants influencing model development, including risk factors, model structure, models’ parameters, data utilisation, economic perspective, equality/equity consideration, transparency and validation process. Second, as a sequential process, is model conceptualisation, to determine which modelling types and their attributes best represent the defined problem. Expert opinions, including a clinician and experienced modellers, provided input on the state transition model to ensure the structure is clinically relevant. From this stage, the consideration and agreement to establish a disease state in a state transition model was discussed.ConclusionThis conceptual model serves as a basis for representing the systematic process for structuring a CMD policy model to enhance its transparency and credibility.

AnophelesModel: An R package to interface mosquito bionomics, human exposure and intervention effects with models of malaria intervention impact.

In recent decades, field and semi-field studies of malaria transmission have gathered geographic-specific information about mosquito ecology, behaviour and their sensitivity to interventions. Mathematical models of malaria transmission can incorporate such data to infer the likely impact of vector control interventions and hence guide malaria control strategies in various geographies. To facilitate this process and make model predictions of intervention impact available for different geographical regions, we developed AnophelesModel. AnophelesModel is an online, open-access R package that quantifies the impact of vector control interventions depending on mosquito species and location-specific characteristics. In addition, it includes a previously published, comprehensive, curated database of field entomological data from over 50 Anopheles species, field data on mosquito and human behaviour, and estimates of vector control effectiveness. Using the input data, the package parameterizes a discrete-time, state transition model of the mosquito oviposition cycle and infers species-specific impacts of various interventions on vectorial capacity. In addition, it offers formatted outputs ready to use in downstream analyses and by other models of malaria transmission for accurate representation of the vector-specific components. Using AnophelesModel, we show how the key implications for intervention impact change for various vectors and locations. The package facilitates quantitative comparisons of likely intervention impacts in different geographical settings varying in vector compositions, and can thus guide towards more robust and efficient malaria control recommendations. The AnophelesModel R package is available under a GPL-3.0 license at https://github.com/SwissTPH/AnophelesModel.

Cost-effectiveness and health impact of screening and treatment of Mycobacterium tuberculosis infection among formerly incarcerated individuals in Brazil: a Markov modelling study

Individuals who were formerly incarcerated have high tuberculosis incidence, but are generally not considered among the risk groups eligible for tuberculosis prevention. We investigated the potential health impact and cost-effectiveness of Mycobacterium tuberculosis infection screening and tuberculosis preventive treatment (TPT) for individuals who were formerly incarcerated in Brazil. Using published evidence for Brazil, we constructed a Markov state transition model estimating tuberculosis-related health outcomes and costs among individuals who were formerly incarcerated, by simulating transitions between health states over time. The analysis compared tuberculosis infection screening and TPT, to no screening, considering a combination of M tuberculosis infection tests and TPT regimens. We quantified health effects as reductions in tuberculosis cases, tuberculosis deaths, and disability-adjusted life-years (DALYs). We assessed costs from a tuberculosis programme perspective. We report intervention cost-effectiveness as the incremental costs per DALY averted, and tested how results changed across subgroups of the target population. Compared with no intervention, an intervention incorporating tuberculin skin testing and treatment with 3 months of isoniazid and rifapentine would avert 31 (95% uncertainty interval 14-56) lifetime tuberculosis cases and 4·1 (1·4-5·8) lifetime tuberculosis deaths per 1000 individuals, and cost US$242 per DALY averted. All test and regimen combinations were cost-effective compared with no screening. Younger age, longer incarceration, and more recent prison release were each associated with significantly greater health benefits and more favourable cost-effectiveness ratios, although the intervention was cost-effective for all subgroups examined. M tuberculosis infection screening and TPT for individuals who were formerly incarcerated appears cost-effective, and would provide valuable health gains. National Institutes of Health. For the Portuguese translation of the abstract see Supplementary Materials section.

US cost-utility model of lenacapavir plus optimized background regimen (OBR) vs fostemsavir plus OBR and ibalizumab plus OBR for people with HIV with multidrug resistance.

Heavily treatment-experienced (HTE) people with HIV (PWH) have limited treatment options owing to multidrug resistance (MDR). Lenacapavir (LEN) is indicated, in combination with other antiretrovirals, for the treatment of adults with MDR HIV-1 experiencing failure of their current antiretroviral regimen because of resistance, intolerance, or safety considerations. To evaluate the cost-utility of LEN in combination with an optimized background regimen (OBR) vs alternative recently approved treatments for HTE PWH, fostemsavir (FTR)+OBR and ibalizumab (IBA)+OBR, for the treatment of PWH with MDR, from a mixed US health care payer perspective. A Markov state-transition model with a lifetime time horizon was developed. Transition probabilities between viral load categories were based on individual participant data from the CAPELLA trial for LEN+OBR and on relative efficacy parameters obtained from indirect treatment comparisons for comparators. Health state utilities were sourced from the literature. Costs included drug acquisition costs, drug administration costs, disease management costs, adverse event costs, AIDS-related event costs, and treatment switching costs and were sourced from red book costs, Medicare and Medicaid fees, and the literature. Costs and outcomes were discounted at 3% annually. The model was used to estimate total and incremental costs, life-years (LYs), quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. A deterministic and a probabilistic sensitivity analysis, as well as scenario analyses, were performed to address elements of uncertainty in the model and to explore the robustness of the results. Over a lifetime time horizon, LEN+OBR was associated with the highest absolute QALYs (9.41) and the greatest number of LYs (12.09) compared with FTR+OBR (QALYs: 8.75; LYs: 11.26) and IBA+OBR (QALYs: 8.36; LYs: 10.78). LEN+OBR was also associated with the lowest total lifetime costs of the 3 interventions (LEN+OBR: $1,441,122 [US dollars]; FTR+OBR: $1,504,986; IBA+OBR: $1,524,396) and therefore was dominant over both comparators in the base case. LEN+OBR remained dominant vs FTR+OBR and IBA+OBR across the range of scenarios tested and LEN+OBR had a 99% probability of being cost-effective compared with FTR+OBR and IBA+OBR in the probabilistic sensitivity analysis at a willingness-to-pay threshold of $50,000/QALY. This economic evaluation demonstrated that LEN+OBR provides meaningful increases in QALYs and LYs, and is dominant over a lifetime time horizon, compared with FTR+OBR and IBA+OBR for the treatment of PWH with MDR in the United States.

O27 DEVELOPMENT OF A CONCEPTUAL EVALUATION MODEL AND TESTING ITS PERFORMANCE IN HYPOTHETICAL PAY-FOR-PERFORMANCE INTERVENTIONS TO IMPROVE HYPERTENSION CONTROL

Background and Objective: Hypertension is a growing concern, particularly in low- and middle-income countries. Financial incentives, such as pay-for-performance, have shown promise in improving non-hypertension outcomes. However, their efficacy and cost-effectiveness in hypertension management, especially in low-resource contexts, remain uncertain. Our objectives were to 1) document studies exploring health financial interventions for hypertension management 2) develop a conceptual model which can facilitate future research on health financing approaches for hypertension management, and 3) assess the model's performance in hypothetical pay-for-performance interventions. Methods: Our literature review identified few studies evaluating finance interventions on hypertension management with somewhat more evidence for pay-for-performance strategies. Thus, we developed a conceptual model and assessed its performance in hypothetical scenarios of pay-for-performance schemes to enhance public hypertension care in Bangladesh. Using a state-transition modeling framework, we estimated the incentive costs and impact on cardiovascular disease burden in 18 scenarios with varying intervention coverage, blood pressure effects, and incentive rates (Figure 1). Key model inputs were derived from the 2019 Global Burden of Disease Study, the 2018 WHO STEPS survey, and WHO-CHOICE. Our primary outcome was incentive costs per health-adjusted life year (HALY) gained. Results: Based on our model, the incentive costs per HALY gained depended on the intervention coverage, intervention effect and incentive rate (Figure). If only currently treated patients were included, the most optimistic scenario (i.e., the largest blood pressure reduction with the lowest incentive rate) was estimated to cost 11,043 USD in incentives per HALY gained (Figure). If the intervention also included new, previously untreated patients while maintaining the same total incentives, the estimated incentive costs per HALY gained was 5,515 USD. Conclusions: Our model suggests that pay-for-performance interventions for hypertension care may demand substantial financial resources, but that the intervention could become more favorable with increased treatment coverage. While more studies on the impact of financial interventions in hypertension care are necessary, our model can guide planning and designing such a study.

Anomaly detection in cyber-physical systems using actuator state transition model

Anomaly detection in cyber-physical systems using actuator state transition model

Decision-making based on Markov decision process in integrated artificial reasoning framework—Part I: Theory

This paper presents a decision-making framework based on an integrated artificial reasoning framework and Markov decision process (MDP). The integrated artificial reasoning framework provides a physics-based approach that converts system information into state transition models, and the analysis result will be represented by the transition probabilities that can be used with an MDP to find a traceable and explainable optimal pathway. A dynamic Bayesian network (DBN) is well suited for representing the structure of an MDP. The causality information among process variables (or among subsystems) is mathematically represented in a DBN by the conditional probabilities of the node’s states provided different probabilities of the parent node’s states. To define node states in a physically understandable manner, we used multilevel flow modeling (MFM). An MFM follows the fundamental energy and mass conservation laws and supports the selection of process variables that represent the system of interest so that causal relations among process variables are properly captured. An MFM-based DBN supports developing state transition models in an MDP to capture the effect of process variables of system having physical relations. The operators of the target system can capture stochastic system dynamics as multiple subsystem state transitions based on their physical relations and uncertainties coming from component degradation or random failures. We analyzed a simplified exemplary system to illustrate an optimal operational policy using the suggested approach.

Budget impact of resmetirom for the treatment of adults with non-cirrhotic non-alcoholic steatohepatitis (NASH) with moderate to advanced liver fibrosis (consistent with stages F2 to F3 fibrosis)

Aims This study assessed the budget impact of resmetirom as a treatment for adults with non-cirrhotic non-alcoholic steatohepatitis (NASH) with moderate-to-advanced liver fibrosis and estimated total costs for a hypothetical private payer in the United States. Materials and methods A three-year budget impact analysis based on an open cohort state transition model was developed for a hypothetical one-million-member private health plan. The comparator was Standard of Care (SOC), defined as routine care for non-cirrhotic NASH patients with moderate-to-advanced liver fibrosis. Each year, the number of resmetirom treatment-eligible patients was estimated through prevalent, incident, and diagnostic rate estimates. Costs included resources incurred by the medical and pharmacy benefits of private payers, including resmetirom drug acquisition costs, diagnosis and monitoring, other medical and other prescription costs stratified by disease progression status (i.e. non-cirrhotic vs. cirrhotic/advanced liver diseases). Resmetirom adverse event management costs were included in sensitivity analysis. Drug costs were estimated based on the average wholesale acquisition cost as of March 2024. Other costs were based on published sources and inflated to 2023 US dollars. Budget impact outcomes were presented in aggregate, net, and on a per-member per-month (PMPM) basis. Results Compared with a scenario without resmetirom, the introduction of resmetirom yielded results ranging from 50 to 238 treated patients, net budget impact of $2.2 to $9.5 million, and PMPM from $0.19 to $0.80 over years one and three. Net costs excluding resmetirom declined over time. In sensitivity analyses, results were most sensitive to diagnostic and epidemiologic inputs. Limitations Market shares are based on internal forecasts, a short time horizon, average treatment effects, and other limitations common to BIMs. Conclusion The adoption of resmetirom on the formulary for the treatment of non-cirrhotic NASH with moderate-to-advanced liver fibrosis resulted in a moderate increase in budget impact with declining costs related to NASH progression.

Economic evaluation of hepatocellular carcinoma surveillance in chronic hepatitis B patients with virological remission

BackgroundSubsequent risk of hepatocellular carcinoma (HCC) persists in chronic hepatitis B (CHB) patients with virological remission. We aimed to assess the cost-effectiveness of HCC surveillance in those patients and determine appropriate age to commence or discontinue surveillance.MethodsWe developed an individual-based state transition model, simulating the advancement of HCC in CHB patients with virological remission. We used this model to compare the incremental cost-effectiveness ratio (ICER) and long-term health outcomes of biannual or annual HCC surveillance for varying durations with no surveillance.ResultsFor compensated cirrhosis patients with CHB, biannual surveillance was not cost-effective for all age groups, while annual surveillance was cost-effective for patients aged 55 to 70 (ICER USD 28,076 / quality-adjusted life years [QALY] gained), which detected 176 additional early HCC cases in a 100,000-person cohort compared to no surveillance. In CHB patients with advanced fibrosis, annual surveillance for patients aged 40 to 75 was the most cost-effective strategy (ICER USD 4,984/QALY gained), which detected 289 additional early HCC per 100,000 patients.ConclusionsAnnual surveillance for patients with compensated cirrhosis or advanced fibrosis was a more cost-effective option that demonstrated substantial economic benefits, being slightly less effective than biannual surveillance at a significantly lower cost, providing insights for professionals in evaluating HCC surveillance among high-risk patients in China.

Cost-effective endoscopic screening for gastric cancer in a cohort with low Helicobacter pylori prevalence.

Periodic endoscopic screening for gastric cancer (GC) is widely performed in East Asia; however, the optimal screening strategy remains unclear. This study aimed to determine the most cost-effective endoscopic screening strategy for the detection and treatment of GC in a cohort with a low Helicobacter pylori prevalence. The following data were retrospectively extracted from participants who received screening endoscopy between April 2019 and March 2023: age, H. pylori infection status, presence of intestinal metaplasia, pathological diagnosis of GC, and the interval between the most recent endoscopies. A Markov state transition model was constructed based on the cohort data. The cost-effectiveness of 15 strategies with different starting ages (40/50/60years) and screening intervals (1/2/3/4/5years) was compared. The net monetary benefit (NMB) and incremental cost-effectiveness ratio (ICER) of quality-adjusted life-years gained by treatment were used as outcomes. A simulation model was constructed based on the cohort data of 94 137 participants (mean age 54.5years, males 57.9%; 74.4% H. pylori-naïve, 94.2% intestinal metaplasia-negative). The results of the base-case analysis showed that the screening strategy of 4-year intervals starting at the age of 40years had the highest NMB (97 401 578 yen). In both the Monte Carlo simulation and one-way sensitivity analysis with a varying probability of H. pylori infection status transition, the ICER was superior in the screening strategy every 4years, starting at age 40years. Our simulation showed that endoscopic screening at 4-year intervals starting at the age of 40years was the most cost-effective method.

Research on standardization of power transformer monitoring and early warning based on multi-source data

To meet the growing demand for integrated monitoring of complex power grid equipment, it is necessary to improve the situational awareness model of power transformers. The model is expected to assist monitoring personnel in timely identifying transformers with deteriorating trends among massive and discrete monitoring information, and to make responses in advance. However, the current transformer state awareness technology generally has the problem of single data source and poor timeliness, and still requires monitoring personnel to make artificial analysis and prediction in combination with telemetry information, which cannot fully meet the requirements of power grid equipment monitoring. This paper is based on multi-source data fusion technology, through associating and mining transformer alarm information, equipment maintenance records and power transmission and transformation online monitoring data, to extract the dimension features of transformer operation situation assessment. By constructing a multi-layer perceptron model, a transformer state transition model based on the principle of Markov chain is established, which can predict possible defects 2 h in advance and achieve good results, and determine the transformer state early warning index, providing sufficient time for monitoring personnel to deploy transformer operation and maintenance work in advance. Finally, the effectiveness of the method proposed in this paper is proved by the case of transformer crisis state in a city substation, and the method proposed in this paper has important significance for transformer state early warning.