Microsimulation Model Research Articles

Cost-utility analysis of a flash continuous glucose monitoring system in the management of people with type 2 diabetes mellitus on basal insulin therapy-An Italian healthcare system perspective.

To assess the cost-utility of the FreeStyle Libre flash continuous glucose monitoring (CGM) system from an Italian healthcare system perspective, when compared with self-monitoring of blood glucose (SMBG) in people living with type 2 diabetes mellitus (T2DM) receiving basal insulin. A patient-level microsimulation model was run using Microsoft Excel for 10 000 patients over a lifetime horizon, with 3.0% discounting for costs and utilities. Inputs were based on clinical trials and real-world evidence, with patient characteristics reflecting Italian population data. The effect of flash CGM was modelled as a persistent 0.8% reduction in glycated haemoglobin versus SMBG. Costs (€ 2023) and disutilities were applied to glucose monitoring, diabetes complications, severe hypoglycaemia, and diabetic ketoacidosis. The health outcome was measured as quality-adjusted life-years (QALYs). Direct costs were €5338 higher with flash CGM than with SMBG. Flash CGM was associated with 0.51 more QALYs than SMBG, giving an incremental cost-effectiveness ratio (ICER) of €10 556/QALY. Scenario analysis ICERs ranged from €3825/QALY to €26 737/QALY. In probabilistic analysis, flash CGM was 100% likely to be cost effective at willingness-to-pay thresholds > €20 000/QALY. From an Italian healthcare system perspective, flash CGM is cost effective compared with SMBG for people living with T2DM on basal insulin.

Emulator-Based Bayesian Calibration of the CISNET Colorectal Cancer Models.

To calibrate Cancer Intervention and Surveillance Modeling Network (CISNET)'s SimCRC, MISCAN-Colon, and CRC-SPIN simulation models of the natural history colorectal cancer (CRC) with an emulator-based Bayesian algorithm and internally validate the model-predicted outcomes to calibration targets. We used Latin hypercube sampling to sample up to 50,000 parameter sets for each CISNET-CRC model and generated the corresponding outputs. We trained multilayer perceptron artificial neural networks (ANNs) as emulators using the input and output samples for each CISNET-CRC model. We selected ANN structures with corresponding hyperparameters (i.e., number of hidden layers, nodes, activation functions, epochs, and optimizer) that minimize the predicted mean square error on the validation sample. We implemented the ANN emulators in a probabilistic programming language and calibrated the input parameters with Hamiltonian Monte Carlo-based algorithms to obtain the joint posterior distributions of the CISNET-CRC models' parameters. We internally validated each calibrated emulator by comparing the model-predicted posterior outputs against the calibration targets. The optimal ANN for SimCRC had 4 hidden layers and 360 hidden nodes, MISCAN-Colon had 4 hidden layers and 114 hidden nodes, and CRC-SPIN had 1 hidden layer and 140 hidden nodes. The total time for training and calibrating the emulators was 7.3, 4.0, and 0.66 h for SimCRC, MISCAN-Colon, and CRC-SPIN, respectively. The mean of the model-predicted outputs fell within the 95% confidence intervals of the calibration targets in 98 of 110 for SimCRC, 65 of 93 for MISCAN, and 31 of 41 targets for CRC-SPIN. Using ANN emulators is a practical solution to reduce the computational burden and complexity for Bayesian calibration of individual-level simulation models used for policy analysis, such as the CISNET CRC models. In this work, we present a step-by-step guide to constructing emulators for calibrating 3 realistic CRC individual-level models using a Bayesian approach. We use artificial neural networks (ANNs) to build emulators that surrogate complex individual-based models to reduce the computational burden in the Bayesian calibration process.ANNs showed good performance in emulating the CISNET-CRC microsimulation models, despite having many input parameters and outputs.Using ANN emulators is a practical solution to reduce the computational burden and complexity for Bayesian calibration of individual-level simulation models used for policy analysis.This work aims to support health decision scientists who want to quantify the uncertainty of calibrated parameters of computationally intensive simulation models under a Bayesian framework.

Projected Health and Economic Burden of Comorbid Gout and Chronic Kidney Disease in a Virtual US Population: A Microsimulation Study.

Gout, a common comorbidity of chronic kidney disease (CKD), is associated with high morbidity and healthcare utilization. However, a large proportion of gout remains undermanaged or untreated which may lead to worse patient outcomes and greater healthcare costs. This study estimates the present and future health and economic burden of controlled and uncontrolled gout in a virtual United States (US) CKD population. A validated microsimulation model was used to project the burden of gout in patients with CKD in the USA through 2035. Databases were utilized to build a virtual CKD population of "individuals" with controlled or uncontrolled gout. Modelling assumptions were made on the basis of the literature, which was sparse in some cases. Health and economic outcomes with the current care (baseline) scenario were evaluated, along with potential benefits of urate-lowering intervention scenarios. The prevalence of comorbid gout and CKD in the USA was projected to increase by 29%, from 7.9 million in 2023 to 9.6 million in 2035 in the baseline scenario. Gout flares, tophi, and comorbidity development were also projected to increase markedly through 2035, with the economic burden of gout in the CKD population subsequently increasing from $38.9 billion in 2023 to $47.3 billion in 2035. An increased use of oral urate-lowering therapies in undermanaged patients, and pegloticase use in patients refractory to oral urate-lowering therapies were also project to result in 744,000 and 353,000 fewer uncontrolled gout cases, respectively, by 2035. Marked reductions in complications and costs ensued. This study projected a substantial increase in comorbid gout and CKD. However, improved use of urate-lowering interventions could mitigate this growth and reduce the health and economic burdens of gout.

Lifetime Health and Economic Outcomes of Biparametric Magnetic Resonance Imaging as First-Line Screening for Prostate Cancer : A Decision Model Analysis.

Contemporary prostate cancer (PCa) screening uses first-line prostate-specific antigen (PSA) testing, possibly followed by multiparametric magnetic resonance imaging (mpMRI) for men with elevated PSA levels. First-line biparametric MRI (bpMRI) screening has been proposed as an alternative. To evaluate the comparative effectiveness and cost-effectiveness of first-line bpMRI versus PSA-based screening. Decision analysis using a microsimulation model. Surveillance, Epidemiology, and End Results database; randomized trials. U.S. men aged 55 years with no prior screening or PCa diagnosis. Lifetime. U.S. health care system. Biennial screening to age 69 years using first-line PSA testing (test-positive threshold, 4 µg/L) with or without second-line mpMRI or first-line bpMRI (test-positive threshold, PI-RADS [Prostate Imaging Reporting and Data System] 3 to 5 or 4 to 5), followed by biopsy guided by MRI or MRI plus transrectal ultrasonography. Screening tests, biopsies, diagnoses, overdiagnoses, treatments, PCa deaths, quality-adjusted and unadjusted life-years saved, and costs. For 1000 men, first-line bpMRI versus first-line PSA testing prevented 2 to 3 PCa deaths and added 10 to 30 life-years (4 to 11 days per person) but increased the number of biopsies by 1506 to 4174 and the number of overdiagnoses by 38 to 124 depending on the biopsy imaging scheme. At conventional cost-effectiveness thresholds, first-line PSA testing with mpMRI followed by either biopsy approach for PI-RADS 4 to 5 produced the greatest net monetary benefits. First-line PSA testing remained more cost-effective even if bpMRI was free, all men with low-risk PCa underwent surveillance, or screening was quadrennial. Performance of first-line bpMRI was based on second-line mpMRI data. Decision analysis suggests that comparative effectiveness and cost-effectiveness of PCa screening are driven by false-positive results and overdiagnoses, favoring first-line PSA testing with mpMRI over first-line bpMRI. National Cancer Institute.

The gender gap in lifetime earnings: A microsimulation approach

AbstractTo obtain a more complete understanding of the persisting gender earnings gap in Germany, this paper investigates both the cross‐sectional and lifetime dimension of gender inequalities. Based on a dynamic microsimulation model, we analyse how gender differences accumulate over work lives to examine the lifetime dimension of the gender gap. We estimate an average gender gap in lifetime earnings of 51.5 per cent for birth cohorts 1964–72. We show that this unadjusted gender lifetime earnings gap increases strongly with the number of children, ranging from 17.3 per cent for childless women to 68.0 per cent for women with three or more children. Results from a counterfactual analysis approach show an adjusted gender gap in lifetime earnings of around 10 per cent, suggesting that the gender gap in lifetime earnings is rather driven by gender differences in observable characteristics than by differences in rewards.

Simulation-based economic evaluation of the Wolbachia method in Brazil: a cost-effective strategy for dengue control

Dengue virus (DENV) is an arbovirus transmitted by Aedes aegypti mosquitoes, which can cause severe conditions such as hemorrhagic fever and dengue shock syndrome. These conditions are associated with adverse social, clinical, and economic consequences in Brazil. Herein, the Wolbachia mosquito replacement method is a promising dengue control strategy. We estimated the economic impact of implementing the Wolbachia mosquito replacement method in seven Brazilian cities. A mathematical microsimulation model tracked nearly 23 million inhabitants over a 20-year period, considering the transitions between five different health states (susceptible, inapparent, outpatient, hospitalised and death). Direct costs included local dengue control programs, Wolbachia implementation and dengue care. Indirect costs related to death and productivity loss, as well as disability-adjusted life-years (DALY) averted were also considered. Without Wolbachia, the model projected 1,762,688 reported dengue cases over 20 years. Implementing the Wolbachia method would avert at least 1,295,566 dengue cases, resulting in lower costs and greater effectiveness in all simulated cities. On average, for every 1000 inhabitants followed for 20 years, the Wolbachia method yielded a cost difference of USD 538,233.68 (BRL 2,691,168.40) and averted 5.56 DALYs. Net monetary benefits (NMB) were positive in all seven cities, ranging from USD 110.72 (BRL 553.59) to USD 1399.19 (BRL 6995.95) per inhabitant. Alternative scenarios have also shown a favourable return on investment with a positive benefit-cost ratio (BCR). Wolbachia is likely a cost-effective strategy in the Brazilian context, consistent with international studies. Sensitivity analysis and alternative scenarios confirmed the robustness of the results. This study was funded by the Wellcome Trust under a grant (224459/Z/21/Z).

Strategies to accelerate the elimination of cervical cancer in British Columbia, Canada: a modelling study.

To eliminate cervical cancer in Canada by 2040, defined as an annual age-standardized incidence rate (ASIR) lower than 4.0 per 100 000 women, the Canadian Partnership Against Cancer (CPAC) identified 3 priorities for action: increasing human papillomavirus (HPV) vaccine coverage, implementing HPV-based screening and increasing screening participation, and improving follow-up after abnormal screen results. Our objective was to explore the impact of these priorities on the projected time to elimination of cervical cancer in British Columbia. We used OncoSim-Cervical, a microsimulation model led and supported by CPAC and developed by Statistics Canada that simulates HPV transmission and the natural history of cervical cancer for the Canadian population. We updated model parameters to reflect BC's historical participation rates and program design. We simulated the transition to HPV-based screening and developed scenarios to explore the additional impact of achieving 90% vaccination coverage, 95% screening recruitment, 90% ontime screening, and 95% follow-up compliance. We projected cervical cancer incidence, ASIR, and year of elimination for the population of BC for 2023-2050. HPV-based screening at current vaccination, participation, and follow-up rates can eliminate cervical cancer by 2034. Increasing on-time screening and follow-up compliance could achieve this target by 2031. Increasing vaccination coverage has a small impact over this time horizon. With the implementation of HPV-based screening, cervical cancer can be eliminated in BC before 2040. Efforts to increase screening participation and follow-up through this transition could potentially accelerate this timeline, but the transition from cytology- to HPV-based screening is fundamental to achieving this goal.

Tobacco smoking, smoking cessation and life expectancy among people with HIV on antiretroviral therapy in South Africa: a simulation modelling study.

As access to effective antiretroviral therapy (ART) has improved globally, tobacco-related illnesses, including cardiovascular disease, cancer and chronic respiratory conditions, account for a growing proportion of deaths among people with HIV (PWH). We estimated the impact of tobacco smoking and smoking cessation on life expectancy among PWH in South Africa. In a microsimulation model, we simulated 18 cohorts of PWH with virologic suppression, each homogenous by sex, initial age (35y/45y/55y) and smoking status (current/former/never). Input parameters were from data sources published between 2008 and 2022. We used South African data to estimate age-stratified mortality hazard ratios: 1.2-2.3 (females)/1.1-1.9 (males) for people with current versus never smoking status; and 1.0-1.3 (females)/1.0-1.5 (males) for people with former versus never smoking status, depending on age at cessation. We assumed smoking status remains unchanged during the simulation; people who formerly smoked quit at model start. Simulated PWH face a monthly probability of disengagement from care and virologic non-suppression. In sensitivity analysis, we varied smoking-associated and HIV-associated mortality risks. Additionally, we estimated the total life-years gained if a proportion of all virologically suppressed PWH stopped smoking. Forty-five-year-old females/males with HIV with virologic suppression who smoke lose 5.3/3.7 life-years compared to PWH who never smoke. Smoking cessation at age 45y adds 3.4/2.4 life-years. Simulated PWH who continue smoking lose more life-years from smoking than from HIV (females, 5.3 vs. 3.0 life-years; males, 3.7 vs. 2.6 life-years). The impact of smoking and smoking cessation increase as smoking-associated mortality risks increase and HIV-associated mortality risks, including disengagement from care, decrease. Model results are most sensitive to the smoking-associated mortality hazard ratio; varying this parameter results in 1.0-5.1 life-years gained from cessation at age 45y. If 10-25% of virologically suppressed PWH aged 30-59y in South Africa stopped smoking now, 190,000-460,000 life-years would be gained. Among virologically suppressed PWH in South Africa, tobacco smoking decreases life expectancy more than HIV. Integrating tobacco cessation interventions into HIV care, as endorsed by the World Health Organization, could substantially improve life expectancy.

Cost-effectiveness of short-course radiotherapy versus long-course chemoradiation in organ preservation for locally advanced rectal cancer.

11089 Background: Short-course radiation therapy (SCRT) has previously been found to be cost-effective compared to long-course chemoradiation (LCRT) for patients with locally advanced rectal cancer undergoing operative management. However, non-operative management protocols have recently become a standard treatment option for patients diagnosed with locally advanced rectal cancer achieving a complete clinical response after total neoadjuvant therapy (TNT) as surgery has significant impacts on quality of life. Recent data suggests higher rates of local regrowth and a correspondingly lower rate of organ preservation with SCRT-TNT compared to LCRT-TNT. With this study, we evaluated the cost-effectiveness of SCRT versus LCRT in the setting of non-operative management for locally advanced rectal cancer. Methods: We built a microsimulation model to simulate 5-year outcomes for 1 million hypothetical patients aged 65 years with locally advanced rectal cancer treated with TNT including either SCRT or LCRT. Patients achieving a complete clinical response with TNT opted for a non-operative management approach, undergoing surgery only with subsequent local progression. Patients not achieving a complete clinical response went directly to surgery. The model incorporated costs, quality of life (measured by health utility), and probabilities of disease progression and death. We extracted probabilities of disease progression and death and health utilities from published literature. We assessed costs from the healthcare payer perspective. We measured cost-effectiveness with incremental cost-effectiveness ratio (ICER), with ICERs under $100,000 per quality-adjusted life-year (QALY) considered cost-effective. One way and probabilistic sensitivity analyses were used to test model uncertainty. Results: We found that compared to SCRT, LCRT increased overall cost by $10,457 and improved effectiveness by 0.16 QALYs resulting in an ICER of $67,200/QALY. The model was most sensitive to assumptions about risks of local recurrence in the non-operative setting, the health utility of non-operative management, and the costs of LCRT and SCRT. The model was not sensitive to assumptions about costs of diagnostic evaluation (i.e. flexible sigmoidoscopy) and probability of distant recurrence. Probabilistic sensitivity analysis demonstrated that LCRT was cost-effective in 91% of iterations. Conclusions: Long-course chemoradiation could represent a cost-effective strategy compared with short-course radiotherapy in the non-operative management of patients with locally advanced rectal cancer. The ongoing ACO/ARO/AIO-18.1 trial testing the hypothesis that LCRT-TNT will increase organ preservation rates relative to SCRT-TNT will help confirm these findings.

Effect of multi-cancer early detection screening on late-stage cancers: A modeling study.

11076 Background: Emerging blood-based multi-cancer early detection (MCED) tests can revolutionize early cancer detection. We evaluated the potential impact of MCED screening in reducing risk of late-stage diagnosis of 12 specific cancers which represent 70% of all cancer incidence in the US. Methods: We developed Simulation Model for MCED (SiMCED), a microsimulation model of 12 solid tumor cancer types: breast, colorectal, endometrial, esophageal, gastric, kidney, liver, lung, ovarian, pancreatic, prostate, and urinary bladder. Transitions between cancer stages (I-IV) were driven by cancer type- and stage-specific dwell times, which were synthesized from published literature and empirical estimates. MCED test sensitivity was derived from the PRE-ASCEND study on average-risk American adults. The model was calibrated to reproduce yearly observed cancer incidence diagnosed symptomatically or through screening as captured in the Surveillance, Epidemiology, and End Results (SEER) database, while accounting for unobserved cancer incidence by age, sex, and cancer type and stage. Using a 50-year time horizon, we simulated 100,000 individuals aged 50 to 84 years. Diagnosis of cancer could arise from usual care (UC) or annual MCED screening. Results: Over the 50-year horizon, MCED screening of 100,000 individuals resulted in 1,323 fewer Stage IV (24%) diagnoses relative to UC, with 38% of Stage IV reductions attributed to non-screening-detectable cancer types (i.e., those without recommended screening guidelines). The table displays absolute and percentage reductions in Stage IV diagnoses for the 8 cancer types with the highest absolute reduction in Stage IV diagnoses. The percentage of Stage IV reduction was 21% for screening-detectable cancers and 29% for non-screening-detectable cancers. Conclusions: Our study suggests that MCED screening could be effective for reducing the incidence of Stage IV cancer, which is associated with the worst survival and quality of life. Of note, MCED has the potential to reduce Stage IV cancer incidence for cancers without recommended screening guidelines. However, the real-world impact of MCED tests and their cost-effectiveness require further investigation. [Table: see text]

Can primary health care mitigate the effects of economic crises on child health in Latin America? An integrated multicountry evaluation and forecasting analysis

Latin American and Caribbean countries are dealing with the combined challenges of pandemic-induced socicoeconomic stress and increasing public debt, potentially leading to reductions in welfare and health-care services, including primary care. We aimed to evaluate the impact of primary health-care coverage on child mortality in Latin America over the past two decades and to forecast the potential effects of primary health-care mitigation during the current economic crisis. This multicountry study integrated retrospective impact evaluations in Brazil, Colombia, Ecuador, and Mexico from 2000 to 2019 with forecasting models covering up to 2030. We estimated the impact of coverage of primary health care on mortality rates in children younger than 5 years (hereafter referred to as under-5 mortality) across different age groups and causes of death, adjusting for all relevant demographic, socioeconomic, and health-care factors, with fixed-effects multivariable negative binomial models in 5647 municipalities with an adequate quality of vital statistics. We also performed several sensitivity and triangulation analyses. We integrated previous longitudinal datasets with validated dynamic microsimulation models and projected trends in under-5 mortality rates under alternative policy response scenarios until 2030. High primary health-care coverage was associated with substantial reductions in post-neonatal mortality rates (rate ratio [RR] 0·72, 95% CI 0·71-0·74), toddler (ie, aged between 1 year and <5 years) mortality rates (0·75, 0·73-0·76), and under-5 mortality rates (0·81, 0·80-0·82), preventing 305 890 (95% CI 251 826-360 517) deaths of children younger than 5 years over the period 2000-19. High primary health-care coverage was also associated with lower under-5 mortality rates from nutritional deficiencies (RR 0·55, 95% CI 0·52-0·58), anaemia (0·64, 0·57-0·72), vaccine-preventable and vaccine-sensitive conditions (0·70, 0·68-0·72), and infectious gastroenteritis (0·78, 0·73-0·84). Considering a scenario of moderate economic crisis, a mitigation response strategy implemented in the period 2020-30 that increases primary health-care coverage could reduce the under-5 mortality rate by up to 23% (RR 0·77, 95% CI 0·72-0·84) when compared with a fiscal austerity response, and this strategy would avoid 142 285 (95% CI 120 217-164 378) child deaths by 2030 in Brazil, Colombia, Ecuador, and Mexico. The improvement in primary health-care coverage in Brazil, Colombia, Ecuador, and Mexico over the past two decades has substantially contributed to improving child survival. Expansion of primary health-care coverage should be considered an effective strategy to mitigate the health effects of the current economic crisis and to achieve Sustainable Development Goals related to child health. UK Medical Research Council. For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

EPH178 Representing Thyroid Cancer Epidemiology in the US Over Time: A Microsimulation Modeling Approach Incorporating Temporal Differences in Thyroid Ultrasound Utilization by Sex and Age

EPH178 Representing Thyroid Cancer Epidemiology in the US Over Time: A Microsimulation Modeling Approach Incorporating Temporal Differences in Thyroid Ultrasound Utilization by Sex and Age

Scenarios of Delayed First Births and Associated Cohort Fertility Levels

Fertility rates among individuals in their 20s have fallen sharply across Europe over the past 50 years. The implications of delayed first births for fertility levels in modern family regimes remain little understood. Using microsimulation models of childbearing and partnership for the 1970–1979 birth cohorts in Italy, Great Britain, Sweden, and Norway, we implement fictive scenarios that reduce the risk of having a first child before age 30 and examine fertility recovery mechanisms for aggregate fertility indicators (the proportion of women with at least one, two, three, or four children; cohort completed fertility rate). Exposure to a first birth increases systematically in the ages following the simulated reduction in first-birth risks, leading to a structural recovery in childbearing that varies across countries according to their fertility and partnership regimes. Full recovery requires an increase in late first-birth risks, with greater increases in countries where late family formation is uncommon and average family sizes are larger: in scenarios where early fertility declines substantially (a linear decline from 50% at age 15 to 0% at age 30), first-birth risks above age 30 would have to increase by 54% in Great Britain, 40% in Norway and Sweden, and 20% in Italy to keep completed fertility constant.

Reframing policy responses to population aging in Iran

Iran is aging rapidly and is expected to see negative population growth rates later this century. This change is generating significant concern for policymakers, whose response is to seek ‘demographic solutions’ to these issues: raise the fertility rate, decrease the divorce rate, and promote marriage among young people. Part of these policies has entailed curtailing access to free family planning services. This ‘call and response’ approach is unlikely to succeed in its stated aim, as it over-simplifies the real challenges of population aging as well as the multiple dimensions of population change. Such policies derive from simple representations of demographic change, most notably using the old-age dependency ratio. Using a microsimulation model, this paper suggests that increasing Iran’s currently low female labor force participation and translating educational gains into rising productivity is a more effective means of responding to the challenges of population aging, even under low fertility conditions. The advancement on previous such microsimulation exercises lies in the fact that this study explicitly considers the comparison between raising fertility and increasing female economic empowerment to offset population aging in a setting characterized by an overt pronatalist policy system. In tandem with reforming stressed institutional systems (such as the pension system), releasing the full potential of Iran’s existing (and future) human capital—especially of its women—is a far more effective policy direction than fertility-promoting policies.

Private Wealth Over the Life Cycle: A Meeting Between Microsimulation and Structural Approaches

AbstractThis paper embeds a structural model of private wealth accumulation over the life cycle within a dynamic microsimulation model designed for long‐run projections of pensions. In such an environment, the optimal savings path results from consumption smoothing and bequests motives, on top of the mortality risk. Preferences are estimated based on a longitudinal wealth survey through a method of simulated moments. Simulations issued from these estimations replicate quite well a private wealth that is more concentrated than labor income. They enable us to compute “augmented” standards of living including capital income, hence to quantify both the countervailing role played by private wealth to earnings dropout after retirement and the impact of the mortality risk in this regard.

A structural microsimulation model for demand-side cost-sharing in healthcare

Demand-side cost-sharing reduces moral hazard in healthcare but increases exposure to out-of-pocket expenditure. We introduce a structural microsimulation model to evaluate both total and out-of-pocket expenditure for different cost-sharing schemes. We use a Bayesian mixture model to capture the healthcare expenditure distributions across different age–gender categories. We estimate the model using Dutch data and simulate outcomes for a number of policies. The model suggests that for a deductible of 300 euros shifting the starting point of the deductible away from zero to 400 euros leads to an average 4% reduction in healthcare expenditure and 47% lower out-of-pocket payments.

Optimal timing of a colonoscopy screening schedule depends on adenoma detection, adenoma risk, adherence to screening and the screening objective: A microsimulation study.

Colonoscopy-based screening provides protection against colorectal cancer (CRC), but the optimal starting age and time intervals of screening colonoscopies are unknown. We aimed to determine an optimal screening schedule for the US population and its dependencies on the objective of screening (life years gained or incidence, mortality, or cost reduction) and the setting in which screening is performed. We used our established open-source microsimulation model CMOST to calculate optimized colonoscopy schedules with one, two, three or four screening colonoscopies between 20 and 90 years of age. A single screening colonoscopy was most effective in reducing life years lost from CRC when performed at 55 years of age. Two, three and four screening colonoscopy schedules saved a maximum number of life years when performed between 49-64 years; 44-69 years; and 40-72 years; respectively. However, for maximum incidence and mortality reduction, screening colonoscopies needed to be scheduled 4-8 years later in life. The optimum was also influenced by adenoma detection efficiency with lower values for these parameters favoring a later starting age of screening. Low adherence to screening consistently favored a later start and an earlier end of screening. In a personalized approach, optimal screening would start earlier for high-risk patients and later for low-risk individuals. In conclusion, our microsimulation-based approach supports colonoscopy screening schedule between 45 and 75 years of age but the precise timing depends on the objective of screening, as well as assumptions regarding individual CRC risk, efficiency of adenoma detection during colonoscopy and adherence to screening.

Cost-Utility Analysis of Berberine Chemoprevention for Colorectal Cancer After Polypectomy.

Background Chemoprevention, such as berberine, has been developed as an alternative or complementary strategy to colonoscopy surveillance and has shown promise in reducing the morbidity and mortality of colorectal cancer. This study aims to evaluate the cost-effectiveness of berberine for postpolypectomy patients from the US third-party payer. Methods A Markov microsimulation model was developed to compare the cost and efficacy of berberine to no intervention, colonoscopy, and the combination of berberine and colonoscopy in postpolypectomy patients. Results After simulating 1 million patients, the study found that colonoscopy alone had a mean cost of $16,391 andmean quality-adjusted life-years (QALYs) of 16.03 per patient, whereas adding berberine slightly reduced the mean cost to $15,609 with a mean QALY of 16.05, making it a dominant strategy. Berberine therapy alone was less effective than colonoscopy alone, with a higher mean cost of $37,480 and a mean QALY of 15.32 per patient. However, berberine therapy was found to be a dominant strategy over no intervention. Conclusions Adding berberine to colonoscopy is the most cost-saving and effective approach for postpolypectomy patients. For patients who refuse or have limited access to colonoscopy, berberine alone is likely to be a dominant strategy compared to no intervention.

#2766 Impact of CKD screening in high-risk populations and guideline-directed therapy on CV event occurrence and costs in Europe: an IMPACT CKD analysis

Abstract Background and Aims Chronic kidney disease (CKD) is a growing health problem in Europe exacerbated by aging and the rise of comorbidities such as diabetes mellitus (DM) and hypertension (HTN). Patients with CKD are often multi-morbid and commonly present with cardiovascular (CV) complications. While CV events including myocardial infarction (MI), stroke, and hospitalization for heart failure (HHF) occur more often in patients with advanced CKD, patients with early-stage CKD are also at increased risk. Patients with CKD also experience an increased risk of CV-related mortality, with many patients dying from CV events prior to kidney failure and renal replacement therapy. CV events also present a significant burden to clinicians and healthcare systems due to the high costs and resource use required to manage and treat them. Despite this multidimensional burden, CKD is currently underdiagnosed in Europe, and CKD screening and treatment are rarely included in public health strategies to improve mortality and health outcomes. This study aims to explore the impact of targeted CKD screening followed by guideline-directed therapy in high-risk populations on CV event occurrence and associated treatment costs across Europe. Method The IMPACT CKD microsimulation model simulates CKD progression, CV events, and comorbidities. CKD status is assigned based on estimated glomerular filtration rate (eGFR) and urine albumin-creatinine ratio levels (UACR), and CKD progression is predicted by an annual eGFR decline rate. The model was used to compare two scenarios in four country populations (Germany, Netherlands, Spain, United Kingdom [UK]): 1) targeted screening for people with DM and/or HTN followed by optimal compliance to guideline-directed therapy and 2) current practice (no screening, underdiagnosis, low treatment rates). Annual targeted screening assumed both eGFR and UACR testing. Treatment initiation for people diagnosed with CKD was based on Kidney Disease Improving Global Outcomes guidelines with a 90% compliance assumed to approximate maximum clinical benefit. Therapies were assumed to have a multiplicative treatment effect on eGFR decline and CV events. Current practice assumed observed diagnosis rates without screening and observed treatment rates in each country. For both scenarios, the model projected incidence of CV events and associated management costs in year 10 (2032) and cumulatively over the 10 simulated years (2023-2032). Results Results compare the targeted screening followed by guideline-directed treatment scenario to continuation of current practices for Germany, Netherlands, Spain, and UK (Table 1). The timely diagnosis of patients with CKD and effective treatment was associated with a reduction of 46.7-53.3%, 38.9-41.6%, and 42.1-50.5% in the number of MI, stroke, and HHF events, respectively in 2032 across the four countries. These decreases in the number of CV events were accompanied by proportional reductions in costs to treat the events. Additionally, this policy approach resulted in declines in the cumulative 10-year CV event development and associated healthcare costs, with MI having the largest reductions (40.6-47.2%), followed by HHF (37.4-43.0%), and stroke (29.8-36.1%) across the four countries. Conclusion This study illustrated that early identification of high-risk patients with CKD coupled with guideline-directed treatment would yield substantial clinical and economic benefits from reducing CV events across all four European countries. Fewer MI, stroke, and HHF events were projected in patients with CKD in both 2032 and cumulatively from 2023 to 2032 due to delayed disease progression following effective interventions. Driven by the reduced clinical burden, lower healthcare costs for CV event management were also predicted. These findings support the need for the adoption of policies for early diagnosis and treatment of CKD to slow disease progression and mitigate the growing CV disease burden among patients with CKD and for health systems. Future studies should explore the costs associated with targeted CKD screening and the guideline-directed pharmacological therapies for CKD.

Measuring population health using health expectancy estimates from morbidity and mortality databases.

The progressive incorporation of quality of life indicators in health planning meets a critical need: The evaluation of the performance of health services, which are under stress by multiple causes, but in particular by an ageing population. In general, national health plans rely on health expectancies obtained using the Sullivan method. The Sullivan health expectancy index combines age-specific mortality rates and age-specific prevalence of healthy life, obtained from health surveys. The objective of this work is to investigate an equivalent estimation, using available information from morbidity and mortality datasets. Mortality and morbidity information, corresponding to years 2016 and 2017, was obtained for the population of the county of Baix Empordà (Catalonia), N = 91,130. Anonymized individual information on diagnoses, procedures and pharmacy consumption contained in the individual clinical record (ICD and ATC codes), were classified into health states. Based on the observed health transitions and mortality, life expectancies by health state were obtained from a multistate microsimulation model. Healthy life expectancies at birth and 65 years for females and males were respectively HLE0female = 39.94, HLE0male = 42.87, HLE65female = 2.43, HLE65male = 2.17. These results differed considerably from the Sullivan equivalents, e.g., 8.25 years less for HLE65female, 9.26 less for HLE65male. Point estimates for global life expectancies at birth and 65 years of age: LE0female = 85.82, LE0male = 80.58, LE65female = 22.31, LE65male = 18.86. Health indicators can be efficiently obtained from multistate models based on mortality and morbidity information, without the use of health surveys. This alternative method could be used for monitoring populations in the context of health planning. Life Expectancy results were consistent with the standard government reports. Due to the different approximation to the concept of health (data-based versus self-perception), healthy life expectancies obtained from multistate micro simulation are consistently lower than those calculated with the standard Sullivan method.