A computer simulation model for cost-effectiveness analysis of mass screening for Type 2 diabetes mellitus

Risk preferences over health: Empirical estimates and implications for medical decision-making

Mainstream health economic theory implies that an expected gain in health-related quality of life (HRQoL) produces the same value for consumers, regardless of baseline health. Several strands of recent research call this implication into question. Generalized Risk-Adjusted Cost-Effectiveness (GRACE) demonstrates theoretically that baseline health status influences value, so long as consumers are not risk-neutral over health. Prior empirical literature casts doubt on risk-neutral expected utility-maximization in the health domain. We estimate utility over HRQoL in a nationally representative U.S. population and use our estimates to measure risk preferences over health. We find that individuals are risk-seeking at low levels of health, become risk-averse at health equal to 0.485 (measured on a 0-1 scale), and are most risk-averse at perfect health (coefficient of relative risk aversion = 4.51). We develop the resulting implications for medical decision making, cost-effectiveness analyses, and the proper theory of health-related decision making under uncertainty.

A systematic review of diabetic retinopathy screening intervals

The current evidence on whether annual diabetic retinopathy (DR) screening intervals can be extended was reviewed. A systematic review protocol was followed (PROSPERO ID: CRD42022359590). Original longitudinal articles that specifically assessed DR screening intervals were in English and collected data after 2000 were included. Two reviewers independently conducted the search and reviewed the articles for quality and relevant information. The heterogeneity of the data meant that a meta-analysis was not appropriate. Twelve publications were included. Studies were of good quality and many used data from DR screening programs. Studies fit into three categories; those that assessed specific DR screening intervals, those that determined optimal DR screening intervals and those that developed/assessed DR screening risk equations. For those with type 2 diabetes, extending screening intervals to 3- to 4-yearly in those with no baseline DR appeared safe. DR risk equations considered clinical factors and allocated those at lower risk of DR progression screening intervals of up to five years. Those with baseline DR or type 1 diabetes appeared to have a higher risk of progression to STDR and needed more frequent screening. DR screening intervals can be extended to 3-5 yearly in certain circumstances. These include patients with type 2 diabetes and no current DR, and those who have optimal management of other risk factors such as glucose and blood pressure.

Cost-effectiveness and cost-utility analysis of type-2 diabetes screening in pharmacies in Iran

Background and purpose

Several studies have shown the effectiveness of screening programs in decreasing the costs and disutility of type-2 diabetes and related complications. As there is a growth in the incidence of type-2 diabetes amongst the Iranian population, the cost-effectiveness of performing type-2 diabetes screening tests in community pharmacies of Iran was evaluated in this study from the payer's perspective. The target population consisted of two hypothetical cohorts of 1000 people 40 years of age without a prior diagnosis of diabetes, for the intervention (screening test) and no-screening groups.

Experimental approach

A Markov model was developed to evaluate the cost-effectiveness and cost-utility of a type-2 diabetes screening test in community pharmacies in Iran. A 30-year time horizon was considered in the model. Three screening programs with 5-year intervals were considered for the intervention group. The evaluated outcomes were quality-adjusted life-years (QALYs) for cost-utility-analysis and life-years-gained (LYG) for cost-effectiveness-analysis. To examine the robustness of the results, one-way and probabilistic-sensitivity analyses were applied to the model.

Findings/Results

The screening test represented both more effects and higher costs. The incremental effects in the base-case scenario (no-discounting) were estimated to be 0.017 and 0.0004 (approximately 0) for QALYs and LYG, respectively. The incremental cost was estimated to be 2.87 USD/patient. The estimated incremental-cost-effectiveness ratio was 164.77 USD/QALY.

Conclusion and implications

This study indicated that screening for type-2 diabetes in community pharmacies of Iran could be considered highly cost-effective, as it meets the WHO criteria of the annual GDP per capita ($2757 in 2020).

Modeling Chronic Kidney Disease in Type 2 Diabetes Mellitus: A Systematic Literature Review of Models, Data Sources, and Derivation Cohorts

INTRODUCTION

As novel therapies for chronic kidney disease (CKD) in type 2 diabetes mellitus (T2DM) become available, their long-term benefits should be evaluated using CKD progression models. Existing models offer different modeling approaches that could be reused, but it may be challenging for modelers to assess commonalities and differences between the many available models. Additionally, the data and underlying population characteristics informing model parameters may not always be evident. Therefore, this study reviewed and summarized existing modeling approaches and data sources for CKD in T2DM, as a reference for future model development.

METHODS

This systematic literature review included computer simulation models of CKD in T2DM populations. Searches were implemented in PubMed (including MEDLINE), Embase, and the Cochrane Library, up to October 2021. Models were classified as cohort state-transition models (cSTM) or individual patient simulation (IPS) models. Information was extracted on modeled kidney disease states, risk equations for CKD, data sources, and baseline characteristics of derivation cohorts in primary data sources.

RESULTS

The review identified 49 models (21 IPS, 28 cSTM). A five-state structure was standard among state-transition models, comprising one kidney disease-free state, three kidney disease states [frequently including albuminuria and end-stage kidney disease (ESKD)], and one death state. Five models captured CKD regression and three included cardiovascular disease (CVD). Risk equations most commonly predicted albuminuria and ESKD incidence, while the most predicted CKD sequelae were mortality and CVD. Most data sources were well-established registries, cohort studies, and clinical trials often initiated decades ago in predominantly White populations in high-income countries. Some recent models were developed from country-specific data, particularly for Asian countries, or from clinical outcomes trials.

CONCLUSION

Modeling CKD in T2DM is an active research area, with a trend towards IPS models developed from non-Western data and single data sources, primarily recent outcomes trials of novel renoprotective treatments.

Economic evaluation of population-based type 2 diabetes mellitus screening at different healthcare settings in Vietnam

Introduction

Few economic evaluations have assessed the cost-effectiveness of screening type-2 diabetes mellitus (T2DM) in different healthcare settings. This study aims to evaluate the value for money of various T2DM screening strategies in Vietnam.

Methods

A decision analytical model was constructed to compare costs and quality-adjusted life years (QALYs) of T2DM screening in different health care settings, including (1) screening at commune health station (CHS) and (2) screening at district health center (DHC), with no screening as the current practice. We further explored the costs and QALYs of different initial screening ages and different screening intervals. Cost and utility data were obtained by primary data collection in Vietnam. Incremental cost-effectiveness ratios were calculated from societal and payer perspectives, while uncertainty analysis was performed to explore parameter uncertainties.

Results

Annual T2DM screening at either CHS or DHC was cost-effective in Vietnam, from both societal and payer perspectives. Annual screening at CHS was found as the best screening strategy in terms of value for money. From a societal perspective, annual screening at CHS from initial age of 40 years was associated with 0.40 QALYs gained while saving US$ 186.21. Meanwhile, one-off screening was not cost-effective when screening for people younger than 35 years old at both CHS and DHC.

Conclusions

T2DM screening should be included in the Vietnamese health benefits package, and annual screening at either CHS or DHC is recommended.

Cost-effectiveness analysis for HbA1c test intervals to screen patients with type 2 diabetes based on risk stratification

BACKGROUND

The best HbA1c test interval strategy for detecting new type 2 diabetes mellitus (T2DM) cases in healthy individuals should be determined with consideration of HbA1c test characteristics, risk stratification towards T2DM and cost effectiveness.

METHODS

State transition models were constructed to investigate the optimal screening interval for new cases of T2DM among each age- and BMI-stratified health individuals. Age was stratified into 30-44-, 45-59-, and 60-74-year-old age groups, and BMI was also stratified into underweight, normal, overweight and obesity. In each model, different HbA1c test intervals were evaluated with respect to the incremental cost-effectiveness ratio (ICER) and costs per quality-adjusted life year (QALY). Annual intervals (Japanese current strategy), every 3 years (recommendations in US and UK) and intervals which are tailored to each risk stratification group were compared. All model parameters, including costs for screening and treatment, rates for complications and mortality and utilities, were taken from published studies. The willingness-to-pay threshold in the cost-effectiveness analysis was set to US $50,000/QALY.

RESULTS

The HbA1c test interval for detecting T2DM in healthy individuals varies by age and BMI. Three-year intervals were the most cost effective in obesity at all ages-30-44: $15,034/QALY, 45-59: $11,849/QALY, 60-74: $8685/QALY-compared with the other two interval strategies. The three-year interval was also the most cost effective in the 60-74-year-old age groups-underweight: $11,377/QALY, normal: $18,123/QALY, overweight: $12,537/QALY-and in the overweight 45-59-year-old group; $18,918/QALY. In other groups, the screening interval for detecting T2DM was found to be longer than 3 years, as previously reported. Annual screenings were dominated in many groups with low BMI and in younger age groups. Based on the probability distribution of the ICER, results were consistent among any groups.

CONCLUSIONS

The three-year screening interval was optimal among elderly at all ages, the obesity at all ages and the overweight in 45-59-year-old group. For those sin the low-BMI and younger age groups, the optimal HbA1c test interval could be longer than 3 years. Annual screening to detect T2DM was not cost effective and should not be applied in any population.

How valid are projections of the future prevalence of diabetes? Rapid reviews of prevalence-based and Markov chain models and comparisons of different models' projections for England

OBJECTIVES

To examine validity of prevalence-based models giving projections of prevalence of diabetes in adults, in England and the UK, and of Markov chain models giving estimates of economic impacts of interventions to prevent type 2 diabetes (T2D).

METHODS

Rapid reviews of both types of models. Estimation of the future prevalence of T2D in England by Markov chain models; and from the trend in the prevalence of diabetes, as reported in the Quality and Outcomes Framework (QOF), estimated by ordinary least squares regression analysis.

SETTING

Adult population in England and UK.

MAIN OUTCOME MEASURE

Prevalence of T2D in England and UK in 2025.

RESULTS

The prevalence-based models reviewed use sample estimates of past prevalence rates by age and sex and projected population changes. Three most recent models, including that of Public Health England (PHE), neither take account of increases in obesity, nor report Confidence Intervals (CIs). The Markov chain models reviewed use transition probabilities between states of risk and death, estimated from various sources. None of their accounts give the full matrix of transition probabilities, and only a minority report tests of validation. Their primary focus is on estimating the ratio of costs to benefits of preventive interventions in those with hyperglycaemia, only one reported estimates of those developing T2D in the absence of a preventive intervention in the general population.Projections of the prevalence of T2D in England in 2025 were (in millions) by PHE, 3.95; from the QOF trend, 4.91 and by two Markov chain models, based on our review, 5.64 and 9.07.

CONCLUSIONS

To inform national policies on preventing T2D, governments need validated models, designed to use available data, which estimate the scale of incidence of T2D and survival in the general population, with and without preventive interventions.

Economic Modelling of Chronic Kidney Disease: A Systematic Literature Review to Inform Conceptual Model Design

BACKGROUND

Chronic kidney disease (CKD) is a progressive condition that leads to irreversible damage to the kidneys and is associated with an increased incidence of cardiovascular events and mortality. As novel interventions become available, estimates of economic and clinical outcomes are needed to guide payer reimbursement decisions.

OBJECTIVE

The aim of the present study was to systematically review published economic models that simulated long-term outcomes of kidney disease to inform cost-effectiveness evaluations of CKD treatments.

METHODS

The review was conducted across four databases (MEDLINE, Embase, the Cochrane library and EconLit) and health technology assessment agency websites. Relevant information on each model was extracted. Transition and mortality rates were also extracted to assess the choice of model parameterisation on disease progression by simulating patient's time with end-stage renal disease (ESRD) and time to ESRD/death. The incorporation of cardiovascular disease in a population with CKD was qualitatively assessed across identified models.

RESULTS

The search identified 101 models that met the criteria for inclusion. Models were classified into CKD models (n = 13), diabetes models with nephropathy (n = 48), ESRD-only models (n = 33) and cardiovascular models with CKD components (n = 7). Typically, published models utilised frameworks based on either (estimated or measured) glomerular filtration rate (GFR) or albuminuria, in line with clinical guideline recommendations for the diagnosis and monitoring of CKD. Generally, two core structures were identified, either a microsimulation model involving albuminuria or a Markov model utilising CKD stages and a linear GFR decline (although further variations on these model structures were also identified). Analysis of parameter variability in CKD disease progression suggested that mean time to ESRD/death was relatively consistent across model types (CKD models 28.2 years; diabetes models with nephropathy 24.6 years). When evaluating time with ESRD, CKD models predicted extended ESRD survival over diabetes models with nephropathy (mean time with ESRD 8.0 vs. 3.8 years).

DISCUSSION

This review provides an overview of how CKD is typically modelled. While common frameworks were identified, model structure varied, and no single model type was used for the modelling of patients with CKD. In addition, many of the current methods did not explicitly consider patient heterogeneity or underlying disease aetiology, except for diabetes. However, the variability of individual patients' GFR and albuminuria trajectories perhaps provides rationale for a model structure designed around the prediction of individual patients' GFR trajectories. Frameworks of future CKD models should be informed and justified based on clinical rationale and availability of data to ensure validity of model results. In addition, further clinical and observational research is warranted to provide a better understanding of prognostic factors and data sources to improve economic modelling accuracy in CKD.

Systematic literature review of the health economic implications of early detection by screening populations at risk for type 2 diabetes

BACKGROUND

Undetected/uncontrolled diabetes is associated with substantial morbidity and mortality and consequent costs. Early detection through screening identifies patients at risk, allowing for earlier treatment initiation.

OBJECTIVES

To determine the economic impact of screening for type 2 diabetes (T2DM).

DATA SOURCES

We systematically reviewed health economic analyses of screening programs for T2DM/pre-diabetes.

STUDY ELIGIBILITY CRITERIA

Published between 2000 and 2015 in any language. Articles must have reported costs of screening, test/patient outcomes and cost-effectiveness.

PARTICIPANTS AND INTERVENTIONS

Any type of screening (universal, targeted, opportunistic) was accepted.

METHODS

Data were extracted from Scopus/Medline/Embase, then tabulated.

RESULTS

There were 137 studies identified, 108 rejected; 29 were analyzed. Screening types included 18 universal, 8 targeted and 8 opportunistic. One study screened for pre-diabetes, 16 for T2DM and 12 examined both. Fourteen (48%) reported costs of screening only, 9 (31%) costs of screening combined with interventions and 6 (21%) presented all costs separately. Screening was compared to no screening in 13 studies (45%); screening was cost-effective in 8 (62%), not cost-effective in 4 (31%) and neither in 1 (8%). When comparing different screening methods, 6 found targeted screening was cost-effective compared with universal screening (none found the opposite), 2 found opportunistic superior to universal. Sensitivity analyses generally confirmed primary findings. Cost drivers included prevalence of T2DM/pre-diabetes, type of blood test used and uptake of testing. For optimal cost-effectiveness, screening for both T2DM and pre-diabetes should be initiated around age 45-50, with repeated testing every 5 years.

CONCLUSIONS/IMPLICATIONS

Targeted screening appears to be cost-effective compared to universal screening.

Long-term effect of population screening for diabetes on cardiovascular morbidity, self-rated health, and health behavior

PURPOSE

There is limited trial evidence concerning the long-term effects of screening for type 2 diabetes on population morbidity. We examined the effect of a population-based diabetes screening program on cardiovascular morbidity, self-rated health, and health-related behaviors.

METHODS

We conducted a pragmatic, parallel-group, cluster-randomized controlled trial of diabetes screening (the ADDITION-Cambridge study) including 18,875 individuals aged 40 to 69 years at high risk of diabetes in 32 general practices in eastern England (27 practices randomly allocated to screening, 5 to no-screening for control). Of those eligible for screening, 466 (2.9%) were diagnosed with diabetes. Seven years after randomization, a random sample of patients was sent a postal questionnaire: 15% from the screening group (including diabetes screening visit attenders and non-attenders) and 40% from the no-screening control group. Self-reported cardiovascular morbidity, self-rated health (using the SF-8 Health Survey and EQ-5D instrument), and health behaviors were compared between trial groups using an intention-to-screen analysis.

RESULTS

Of the 3,286 questionnaires mailed out, 1,995 (61%) were returned, with 1,945 included in the analysis (screening: 1,373; control: 572). At 7 years, there were no significant differences between the screening and control groups in the proportion of participants reporting heart attack or stroke (OR = 0.90, 95% CI, 0.71-1.15); SF-8 physical health summary score as an indicator of self-rated health status (β -0.33, 95% CI, -1.80 to 1.14); EQ-5D visual analogue score (β: 0.80, 95% CI, -1.28 to 2.87); total physical activity (β 0.50, 95% CI, -4.08 to 5.07); current smoking (OR 0.97, 95% CI, 0.72 to 1.32); and alcohol consumption (β 0.14, 95% CI, -1.07 to 1.35).

CONCLUSIONS

Invitation to screening for type 2 diabetes appears to have limited impact on population levels of cardiovascular morbidity, self-rated health status, and health behavior after 7 years.

Community health awareness of diabetes (CHAD): description of a community-wide diabetes awareness demonstration program and its feasibility

OBJECTIVE

This article describes the Community Health Awareness Diabetes (CHAD) program and its feasibility. Developing and testing the feasibility of strategies to detect diabetes in the community is an important primary care issue. The CHAD program was designed to be a feasible and reproducible, low-cost community program to identify high-risk individuals for subsequent diabetes screening by their family doctors.

METHODS

Participants from Grimsby, Ontario, older than age 40, were invited to self-risk-assess for diabetes using a validated questionnaire and 2 near-patient blood tests (capillary blood glucose and glycosylated hemoglobin). Some participants were self-selected, having seen advertising for the program, others were invited by a letter from their family doctor. None of the participants had pre-existing diabetes. Numbers and characteristics of participants, numbers found at risk and satisfaction of participants were examined.

RESULTS

There were 588 participants in CHAD. Of these, the majority had received invitation letters, the majority of participants were seniors and were females, 526 did not have pre-existing diabetes and 16% of participants (n=84 of 526) were identified as being at high risk for diabetes. Participants at high risk of diabetes had significantly more modifiable risk factors, including higher fat, fast food and salt intake, and higher systolic blood pressure. Satisfaction with the program was high.

CONCLUSIONS

The CHAD program was feasible and participants were satisfied with it. Participants had a large number of modifiable risk factors. This program could be repeated in other communities and modified to suit the infrastructure of the area.

An economic evaluation for prevention of diabetes mellitus in a developing country: a modelling study

BACKGROUND

The serious consequences of diabetes mellitus, and the subsequent economic burden, call for urgent preventative action in developing countries. This study explores the clinical and economic outcomes of strategies that could potentially prevent diabetes based on Chinese circumstances. It aims to provide indicators for the long-term allocation of healthcare resources for authorities in developing countries.

METHODS

A representative sample of Chinese adults was used to create a simulated population of 20,000 people aged 25 years and above. The hybrid decision tree Markov model was developed to compare the long-term clinical and economic outcomes of four simulated diabetes prevention strategies with a control group, where no prevention applied. These preventive strategies were the following: (i) one-off screening for undiagnosed diabetes and impaired glucose tolerance (IGT), with lifestyle interventions on diet, (ii) on exercise, (iii) on diet combined exercise (duo-intervention) respectively in those with IGT, and (iv) one-off screening alone. Independent age-specific models were simulated based on diverse incidences of diabetes, mortalities and health utilities. The reported outcomes were the following: the remaining survival years, the quality-adjusted life years (QALYs) per diabetes or IGT subjects, societal costs per simulated subject and the comparisons between preventions and control over 40 years. Sensitivity analyses were performed based on variations of all assumptions, in addition to the performance and the compliance of screening.

RESULTS

Compared with the control group, all simulated screening programmes prolonged life expectancy at the initiation ages of 25 and 40 years, postponed the onset of diabetes and increased QALYs at every initiation age. Along with an assumption of six years intervention, prevention programmes were associated with cost-saving compared with the control group, especially in the population aged 25 years. The savings were at least US$2017 per subject, but no statistically significant difference was observed among the intervention strategies within each age groups. The cost savings were reduced when screening was affected by poor performance and noncompliance.

CONCLUSIONS

Developing countries have few effective strategies to manage the prevention of diabetes. One-off screening for undiagnosed diabetes and IGT, with appropriate lifestyle interventions for those with IGT are cost saving in China, especially in young adults.

How much does screening bring forward the diagnosis of type 2 diabetes and reduce complications? Twelve year follow-up of the Ely cohort

AIMS

There are continuing uncertainties about how much screening for type 2 diabetes brings forward the clinical diagnosis and the impact that earlier diagnosis has on health outcomes. We compared the duration of diabetes and health outcomes in a population invited for diabetes screening at 5-yearly intervals from 1990 (screened population) with those in a similar population not invited for screening (unscreened population).

METHODS

This was a parallel-group, cohort study of people aged 40-65 years, free of known diabetes, identified from the population register of a general practice in Ely, Cambridgeshire, UK (n = 4,936). In 1990-1992, one-third (n = 1,705), selected randomly, received an invitation for screening for diabetes and cardiovascular risk factors at 5-yearly intervals (screened population). From the remainder of the sampling frame, 1,705 randomly selected individuals were invited to diabetes screening 10 years later (unscreened population). Patients with diabetes from both populations were invited for a health assessment, including biochemical, anthropometric and questionnaire measures, and testing for the presence of diabetic complications

RESULTS

Of the 199 eligible individuals with diabetes diagnosed during follow-up, 152 (76%) attended for health assessment. The median duration of clinically recognised diabetes was significantly longer in cases arising in the screened (5.0 years) compared with the unscreened population (1.7 years; p = 0.006). Clinical measures, prescribed medication and functional status were similar between screened and unscreened populations.

CONCLUSIONS

Diabetes screening resulted in cases being identified on average 3.3 years earlier, a difference significantly shorter than previous estimates. Earlier diagnosis did not appear to impact on health outcomes. Further evidence is needed to justify the introduction of population-based screening.

Screening for type 2 diabetes and dysglycemia

Type 2 diabetes mellitus (T2DM) and dysglycemia (impaired glucose tolerance and/or impaired fasting glucose) are increasingly contributing to the global burden of diseases. The authors reviewed the published literature to critically evaluate the evidence on screening for both conditions and to identify the gaps in current understanding. Acceptable, relatively simple, and accurate tools can be used to screen for both T2DM and dysglycemia. Lifestyle modification and/or medication (e.g., metformin) are cost-effective in reducing the incidence of T2DM. However, their application is not yet routine practice. It is unclear whether diabetes-prevention strategies, which influence cardiovascular risk favorably, will also prevent diabetic vascular complications. Cardioprotective therapies, which are cost-effective in preventing complications in conventionally diagnosed T2DM, can be used in screen-detected diabetes, but the magnitude of their effects is unknown. Economic modeling suggests that screening for both T2DM and dysglycemia may be cost-effective, although empirical data on tangible benefits in preventing complications or death are lacking. Screening for T2DM is psychologically unharmful, but the specific impact of attributing the label of dysglycemia remains uncertain. Addressing these gaps will inform the development of a screening policy for T2DM and dysglycemia within a holistic diabetes prevention and control framework combining secondary and high-risk primary prevention strategies.

Age at initiation and frequency of screening to detect type 2 diabetes: a cost-effectiveness analysis

BACKGROUND

No clinical trials have assessed the effects or cost-effectiveness of sequential screening strategies to detect new cases of type 2 diabetes. We used a mathematical model to estimate the cost-effectiveness of several screening strategies.

METHODS

We used person-specific data from a representative sample of the US population to create a simulated population of 325,000 people aged 30 years without diabetes. We used the Archimedes model to compare eight simulated screening strategies for type 2 diabetes with a no-screening control strategy. Strategies differed in terms of age at initiation and frequency of screening. Once diagnosed, diabetes treatment was simulated in a standard manner. We calculated the effects of each strategy on the incidence of type 2 diabetes, myocardial infarction, stroke, and microvascular complications in addition to quality of life, costs, and cost per quality-adjusted life-year (QALY).

FINDINGS

Compared with no screening, all simulated screening strategies reduced the incidence of myocardial infarction (3-9 events prevented per 1000 people screened) and diabetes-related microvascular complications (3-9 events prevented per 1000 people), and increased the number of QALYs (93-194 undiscounted QALYs) added over 50 years. Most strategies prevented a significant number of simulated deaths (2-5 events per 1000 people). There was little or no effect of screening on incidence of stroke (0-1 event prevented per 1000 people). Five screening strategies had costs per QALY of about US$10,500 or less, whereas costs were much higher for screening started at 45 years of age and repeated every year ($15,509), screening started at 60 years of age and repeated every 3 years ($25,738), or a maximum screening strategy (screening started at 30 years of age and repeated every 6 months; $40,778). Several strategies differed substantially in the number of QALYs gained. Costs per QALY were sensitive to the disutility assigned to the state of having diabetes diagnosed with or without symptoms.

INTERPRETATION

In the US population, screening for type 2 diabetes is cost effective when started between the ages of 30 years and 45 years, with screening repeated every 3-5 years.

FUNDING

Novo Nordisk, Bayer HealthCare, [corrected] and Pfizer.

Cost-effectiveness analysis of a two-stage screening intervention for hepatocellular carcinoma in Taiwan

BACKGROUND/PURPOSE

Hepatocellular carcinoma (HCC) has been the leading cause of cancer death in Taiwan since the 1980s. A two-stage screening intervention was introduced in 1996 and has been implemented in a limited number of hospitals. The present study assessed the costs and health outcomes associated with the introduction of screening intervention, from the perspective of the Taiwanese government. The cost-effectiveness analysis aimed to assist informed decision making by the health authority in Taiwan.

METHODS

A two-phase economic model, 1-year decision analysis and a 60-year Markov simulation, was developed to conceptualize the screening intervention within current practice, and was compared with opportunistic screening alone. Incremental analyses were conducted to compare the incremental costs and outcomes associated with the introduction of the intervention. Sensitivity analyses were performed to investigate the uncertainties that surrounded the model.

RESULTS

The Markov model simulation demonstrated an incremental cost-effectiveness ratio (ICER) of NT$498,000 (US$15,600) per life-year saved, with a 5% discount rate. An ICER of NT$402,000 (US$12,600) per quality-adjusted life-year was achieved by applying utility weights. Sensitivity analysis showed that excess mortality reduction of HCC by screening and HCC incidence rates were the most influential factors on the ICERs. Scenario analysis also indicated that expansion of the HCC screening intervention by focusing on regular monitoring of the high-risk individuals could achieve a more favorable result.

CONCLUSION

Screening the population of high-risk individuals for HCC with the two-stage screening intervention in Taiwan is considered potentially cost-effective compared with opportunistic screening in the target population of an HCC endemic area.

Value of biologic therapy: a forecasting model in three disease areas

OBJECTIVE

Forecast the return on investment (ROI) for advances in biologic therapies in years 2015 and 2030, based upon impact on disease prevalence, morbidity, and mortality for asthma, diabetes, and colorectal cancer.

METHODS

A deterministic, spreadsheet-based, forecasting model was developed based on trends in demographics and disease epidemiology. 'Return' was defined as reductions in disease burden (prevalence, morbidity, mortality) translated into monetary terms; 'investment' was defined as the incremental costs of biologic therapy advances. Data on disease prevalence, morbidity, mortality, and associated costs were obtained from government survey statistics or published literature. Expected impact of advances in biologic therapies was based on expert opinion. Gains in quality-adjusted life years (QALYs) were valued at $100,000 per QALY.

RESULTS

The base case analysis, in which reductions in disease prevalence and mortality predicted by the expert panel are not considered, shows the resulting ROIs remain positive for asthma and diabetes but fall below $1 for colorectal cancer. Analysis involving expert panel predictions indicated positive ROI results for all three diseases at both time points, ranging from $207 for each incremental dollar spent on biologic therapies to treat asthma in 2030, to $4 for each incremental dollar spent on biologic therapies to treat colorectal cancer in 2015. If QALYs are not considered, the resulting ROIs remain positive for all three diseases at both time points.

CONCLUSIONS

Society may expect substantial returns from investments in innovative biologic therapies. These benefits are most likely to be realized in an environment of appropriate use of new molecules.

LIMITATIONS

The potential variance between forecasted (from expert opinion) and actual future health outcomes could be significant. Similarly, the forecasted growth in use of biologic therapies relied upon unvalidated market forecasts.

The impact of learned resourcefulness on quality of life in type II diabetic patients: a cross-sectional correlational study

It is well recognized that patients with diabetes encounter a host of daily self-care issues, including controlling blood sugar and preventing and managing complications, which impact significantly upon quality of life. Studies have indicated that learned resourcefulness has a potentially positive effect in dealing with psychosocial and health problems. The purpose of this study was to test the relationship between learned resourcefulness and quality of life in type II diabetic patients. The mediating and moderating effects of learned resourcefulness on the relationship between metabolic control and quality of life of diabetic patients was also examined. This cross-sectional and correlational study included a convenience sample of 131 type II diabetic patients recruited from three hospitals in southern Taiwan. Data were collected through questionnaires, which included the Rosenbaum's Self Control Schedule and World Health Organization's Quality of Life (Short Version). Multiple regression techniques were used to analyze outcome predictors. Study findings include identification of a mediating effect of learned resourcefulness between metabolic control and quality of life. While most DM patients were not satisfied with their health, we found that those with greater learned resourcefulness enjoyed a better quality of life. Learned resourcefulness, gender, and HbA1C explained 35.2% of variance in DM patient quality of life. Male diabetic patients enjoyed a better quality of life than females, even though levels of learned resourcefulness between the two groups were not significantly different. Results indicate that poor metabolic control of diabetic patients has a detrimental effect on quality of life, and when diabetic patients use more self-control skills, they may achieve better quality of life. Results suggest that nurses who use cognitive behavior coping strategies (resourcefulness) may help diabetic patients achieve better metabolic control and promote better quality of life.

Different strategies for screening and prevention of type 2 diabetes in adults: cost effectiveness analysis

OBJECTIVE

To compare four potential screening strategies, and subsequent interventions, for the prevention and treatment of type 2 diabetes: (a) screening for type 2 diabetes to enable early detection and treatment, (b) screening for type 2 diabetes and impaired glucose tolerance, intervening with lifestyle interventions in those with a diagnosis of impaired glucose tolerance to delay or prevent diabetes, (c) as for (b) but with pharmacological interventions, and (d) no screening.

DESIGN

Cost effectiveness analysis based on development and evaluation of probabilistic, comprehensive economic decision analytic model, from screening to death.

SETTING

A hypothetical population, aged 45 at time of screening, with above average risk of diabetes.

DATA SOURCES

Published clinical trials and epidemiological studies retrieved from electronic bibliographic databases; supplementary data obtained from the Department of Health statistics for England and Wales, the screening those at risk (STAR) study, and the Leicester division of the ADDITION study.

METHODS

A hybrid decision tree/Markov model was developed to simulate the long term effects of each screening strategy, in terms of both clinical and cost effectiveness outcomes. The base case model assumed a 50 year time horizon with discounting of both costs and benefits at 3.5%. Sensitivity analyses were carried out to investigate assumptions of the model and to identify which model inputs had most impact on the results.

RESULTS

Estimated costs for each quality adjusted life year (QALY) gained (discounted at 3.5% a year for both costs and benefits) were pound14,150 (euro17 560; $27,860) for screening for type 2 diabetes, pound6242 for screening for diabetes and impaired glucose tolerance followed by lifestyle interventions, and pound7023 for screening for diabetes and impaired glucose tolerance followed by pharmacological interventions, all compared with no screening. At a willingness-to-pay threshold of pound20,000 the probability of the intervention being cost effective was 49%, 93%, and 85% for each of the active screening strategies respectively.

CONCLUSIONS

Screening for type 2 diabetes and impaired glucose tolerance, with appropriate intervention for those with impaired glucose tolerance, in an above average risk population aged 45, seems to be cost effective. The cost effectiveness of a policy of screening for diabetes alone, which offered no intervention to those with impaired glucose tolerance, is still uncertain.

What determines the cost-effectiveness of diabetes screening?

AIMS/HYPOTHESIS

The cost-effectiveness of screening for diabetes is unknown but has been modelled previously. None of these models has taken account of uncertainty. We aimed to describe these uncertainties in a model where the outcome was CHD risk.

SUBJECTS AND METHODS

Our model used population data from the Danish Inter99 study, and simulations were run in a theoretical population of 1,000,000 individuals. CHD risk was estimated using the UK Prospective Diabetes Study (UKPDS) risk engine, and risk reduction from published randomised clinical trials. Probabilistic sensitivity analysis was used to provide confidence intervals for modelled outputs. Uncertain parameter values were independently simulated from distributions derived from existing literature and deterministic sensitivity analysis performed using multiple model runs under different strategy choices and using extreme parameter estimates.

RESULTS

In the least conservative model (low costs and multiplicative risk reduction for combined treatments), the 95% confidence interval of the incremental cost-effectiveness ratio varied from pound23,300-82,000. The major contributors to this uncertainty were treatment risk reduction model parameters: the risk reduction for hypertension treatment and UKPDS risk model intercept. Overall cost-effectiveness ratio was not sensitive to decisions about which groups to screen, nor the costs of screening or treatment. It was strongly affected by assumptions about how treatments combine to reduce risk.

CONCLUSIONS/INTERPRETATION

Our model suggests that there is considerable uncertainty about whether or not screening for diabetes would be cost-effective. The most important but uncertain parameter is the effect of treatment. In addition to directly influencing current policy decisions, health care modelling can identify important unknown or uncertain parameters that may be the target of future research.

Model-Based Evaluation of Diabetic Foot Prevention Strategies in Austria

Diabetes mellitus affects approximately 171 million individuals worldwide. The costs of the adult form of diabetic mellitus account for up to 6% of total health care expenditures in industrialized countries. About 25% of these diabetics develop disabling and most painful foot complications accounting for about 17% of the direct lifetime costs. Diabetic foot prevention programs have been recently introduced in some Austrian federal states to meet the diabetic health targets of the Austrian Health Plan and the St. Vincent Declaration. We developed a new age-group specific Markov model combined with a Monte Carlo simulation model to help policymakers analyze the cost-effectiveness of such programs compared to the status quo in terms of incremental costs per quality-adjusted life years gained (QALY). The Markov model revealed that diabetic foot prevention programs were cost saving when targeted at patients at high risk and mainly cost-effective when targeted at patients with mild symptoms. The Monte Carlo simulation showed that only large scope prevention programs would fulfill the specified reductions in the number of diabetic foot complications as defined in the Austrian Health Plan and the St. Vincent Declaration. Our results clearly indicate the enormous impact of diabetic foot prevention programs.

Controlling the diabetes epidemic: how should we screen for undiagnosed diabetes and dysglycaemia?

AIMS

To compare the detection of undiagnosed diabetes and dysglycaemia (impaired glucose tolerance, impaired fasting glucose, diabetes) using risk factors and laboratory measures of glycaemia.

METHODS

Casual blood glucose samples were taken from 1899 (69.4% of 2737 invited) European, Maori and Pacific Islands subjects aged 40-79 years from randomly selected households in South Auckland, New Zealand. Of these, 534 attended for a 75-g oral glucose tolerance test (OGTT) if an elevated result was identified [327/478 (68.4%)] or if randomly selected with a 'normal' screening result [207/308 (67.2%)].

RESULTS

Several Europeans with undiagnosed diabetes (25.0%) and dysglycaemia (31.4%) had no diabetes risk factors. Most Maori and Pacific Islanders had at least one risk factor. The area under the receiver operating curve (ROC) for the detection of undiagnosed diabetes was 0.92 (0.89-0.95) using fasting glucose, 0.86 (0.82-0.90) using HbA1c, 0.75 (0.69-0.80) using random glucose, but 0.60 (0.55-0.66) using risk factor screening. The ROC for detecting any dysglycaemia was 0.88 (0.85-0.90), 0.68 (0.64-0.71), 0.72 (0.69-0.75), 0.61 (0.58-0.65), respectively. Screening using fasting glucose (the best test) detected 90.4% of new diabetes and 78.4% of dysglycaemia; risk factor screening followed by fasting glucose detected significantly less cases [88 (82-93)% and 86 (82-89)%, respectively] with 9.2% less OGTTs.

CONCLUSIONS

Using risk factors for the identification of who should receive a blood test for dysglycaemia adds little to direct screening with the risk of missing some with significant hyperglycaemia. Screening for dysglycaemia may best be undertaken using blood tests without initial risk factor symptom screening.

Cost-effectiveness analysis of different screening procedures for type 2 diabetes: the KORA Survey 2000

OBJECTIVE

To compare the cost-effectiveness of different type 2 diabetes screening strategies using population-based data (KORA Survey; Augsburg, Germany; subjects aged 55-74 years), including participation data.

RESEARCH DESIGN AND METHODS

The decision analytic model, which had a time horizon of 1 year, used the following screening strategies: fasting glucose testing, the oral glucose tolerance test (OGTT) following fasting glucose testing in impaired fasting glucose (IFG) (fasting glucose + OGTT), OGTT only, and OGTT if HbA(1c) was >5.6% (HbA(1c) + OGTT), all with or without first-step preselection (p). The main outcome measures were costs (in Euros), true-positive type 2 diabetic cases, incremental cost-effectiveness ratios (ICERs), third-party payers, and societal perspectives.

RESULTS

After dominated strategies were excluded, the OGTT and HbA(1c) + OGTT from the perspective of the statutory health insurance remained, as did fasting glucose + OGTT and HbA(1c) + OGTT from the societal perspective. OGTTs (4.90 per patient) yielded the lowest costs from the perspective of the statutory health insurance and fasting glucose + OGTT (10.85) from the societal perspective. HbA(1c) + OGTT was the most expensive (21.44 and 31.77) but also the most effective (54% detected cases). ICERs, compared with the next less effective strategies, were 771 from the statutory health insurance and 831 from the societal perspective. In the Monte Carlo analysis, dominance relations remained unchanged in 100 and 68% (statutory health insurance and societal perspective, respectively) of simulated populations.

CONCLUSIONS

The most effective screening strategy was HbA(1c) combined with OGTT because of high participation. However, costs were lower when screening with fasting glucose tests combined with OGTT or OGTT alone. The decision regarding which is the most favorable strategy depends on whether the goal is to identify a high number of cases or to incur lower costs at reasonable effectiveness.