The Effects of Diagnostic Definitions in Claims Data on Healthcare Cost Estimates: Evidence from a Large-Scale Panel Data Analysis of Diabetes Care in Japan

The Long-Term Cost-Effectiveness of Tirzepatide 5 mg versus Dulaglutide 0.75 mg for the Treatment of People with Type 2 Diabetes in Japan

INTRODUCTION

This analysis aimed to evaluate the long-term cost-effectiveness of tirzepatide 5 mg versus dulaglutide 0.75 mg (both administered once weekly) in people not achieving glycemic control on metformin, based on the results of the head-to-head SURPASS J-mono trial from a Japanese healthcare payer perspective.

METHODS

A cost-utility analysis was performed over a 50-year time horizon using an implementation of the UKPDS Outcomes Model 2 developed in Microsoft Excel. Baseline cohort characteristics, treatment effects and adverse event rates were sourced from the SURPASS J-mono trial. Simulated patients were assumed to receive either tirzepatide 5 mg or dulaglutide 0.75 mg until HbA1c exceeded 8.0%, at which point treatment was discontinued and basal insulin was initiated. Direct costs were derived from the Japan Medical Data Center claims database. Future costs and clinical benefits were discounted at 2% annually.

RESULTS

In this cost-utility modeling analysis, tirzepatide 5 mg was associated with lower diabetes-related complication rates, improved life expectancy, improved quality-adjusted life expectancy and higher direct costs versus dulaglutide 0.75 mg. This resulted in an incremental cost-effectiveness ratio (ICER) of JPY (Japanese yen) 1,302,240 per quality-adjusted life year (QALY) gained for tirzepatide 5 mg versus dulaglutide 0.75 mg (JPY 140 = USD 1). Tirzepatide remained cost-effective versus dulaglutide over a range of sensitivity analyses.

CONCLUSIONS

In this analysis, tirzepatide 5 mg was associated with an ICER below the commonly quoted willingness-to-pay threshold of JPY 5,000,000 per QALY gained, suggesting that tirzepatide is a cost-effective treatment option for adult patients with type 2 diabetes mellitus, compared with dulaglutide 0.75 mg.

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

AIM

To assess the cost-effectiveness of diabetic nephropathy treatment with sodium-glucose cotransporter-2 (SGLT2) inhibitors in Japanese clinical practice, considering diabetes-related complications.

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Cost-effectiveness of behavioural counselling intervention compared with non-intervention for adult patients with metabolic syndrome to prevent cardiovascular diseases and type 2 diabetes in Japan: a microsimulation modelling study

OBJECTIVES

Nationwide lifestyle intervention-specific health guidance (SHG) in Japan-employs counselling and education to change unhealthy behaviours that contribute to metabolic syndrome, especially obesity or abdominal obesity. We aimed to perform a model-based economic evaluation of SHG in a low participation rate setting.

DESIGN

A hypothetical population, comprised 50 000 Japanese aged 40 years who met the criteria of the SHG, used a microsimulation using the Markov model to evaluate SHG's cost-effectiveness compared with non-SHG. This hypothetical population was simulated over a 35-year time horizon.

SETTING

SHG is conducted annually by all Japanese insurers.

OUTCOME MEASURES

Model parameters, such as costs and health outcomes (including quality-adjusted life-years, QALYs), were based on existing literature. Incremental cost-effectiveness ratios were estimated from the healthcare payer's perspective. Deterministic and probabilistic sensitivity analyses (PSA) were conducted to evaluate the uncertainty around the model input parameters.

RESULTS

The simulation revealed that the total costs per person in the SHG group decreased by JPY53 014 (US$480) compared with that in the non-SHG group, and the QALYs increased by 0.044, wherein SHG was considered the dominant strategy despite the low participation rates. PSA indicated that the credibility intervals (2.5th-97.5th percentile) of the incremental costs and the incremental QALYs with the SHG group compared with the non-SHG group were -JPY687 376 to JPY85 197 (-US$6226 to US$772) and -0.009 to 0.350 QALYs, respectively. Each scenario analysis indicated that programmes for improving both blood pressure and blood glucose levels among other risk factors for metabolic syndrome are essential for improving cost-effectiveness.

CONCLUSIONS

This study suggests that even small effects of counselling and education on behavioural modification may lead to the prevention of acute life-threatening events and chronic diseases, in addition to the reduction of medication resulting from metabolic syndrome, which results in cost savings.

Developing a health economic model for Asians with type 2 diabetes based on the Japan Diabetes Complications Study and the Japanese Elderly Diabetes Intervention Trial

INTRODUCTION

Cost-effectiveness analyses are becoming increasingly important in Japan following the introduction of a health technology assessment scheme. The study objective was to develop an economic model to evaluate the cost-effectiveness of two interventions for type 2 diabetes in a Japanese population.

RESEARCH DESIGN AND METHODS

The Japan Diabetes Complications Study/Japanese Elderly Diabetes Intervention Trial risk engine (JJRE) Cost-Effectiveness Model (JJCEM) was developed, incorporating validated risk equations in Japanese patients with type 2 diabetes from the JJRE. Weibull regression models were developed for progression of the model outcomes, and a targeted literature review was performed to inform default values for utilities and costs. To illustrate outcomes, two simulated analyses were performed in younger (aged 40 years) and older (aged 80 years) Japanese populations, comparing a hypothetical treatment with placebo.

RESULTS

The model considers a population based on user-defined values for 11 baseline characteristic parameters and simulates rates of diabetic complications over a defined time horizon. Costs, quality-adjusted life years, and an incremental cost-effectiveness ratio are estimated. The model provides disaggregated results for two competing interventions, allowing visualization of the key drivers of cost and utility. A scatterplot of simulations and cost-effectiveness acceptability curve are generated for each analysis.

CONCLUSIONS

This is the first cost-effectiveness model for East Asian patients with type 2 diabetes, developed using Japan-specific risk equations. This population constitutes the largest share of the global population with diabetes, making this model highly relevant. The model can be used to evaluate the cost-effectiveness of anti-diabetic interventions in patients with type 2 diabetes in Japan and other East Asian populations.

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.

Current trends in diabetes mellitus database research in Japan

With the widespread use of electronic medical records and administrative claims databases, analytic results from so-called real-world data have become increasingly important in healthcare decision-making. Diabetes mellitus is a heterogeneous condition that involves a broad spectrum of patients. Real-world database studies have been recognised as a powerful tool to understand the impact of current practices on clinical courses and outcomes, such as long-term glucose control, development of microvascular or macro-vascular diseases, and mortality. Diabetes is also a major global health issue and poses a significant social and economic burden worldwide. Therefore, it is critical to understand the epidemiology, clinical course, treatment reality, and long-term outcomes of diabetes to determine realistic solutions to a variety of disease-related issues that we are facing. In the present review, we summarise the healthcare system and large-scale databases currently available in Japan, introduce the results from recent database studies involving Japanese patients with diabetes, and discuss future opportunities and challenges for the use of databases in the management of diabetes.

Prevalence and effects of suicidal ideation diagnosis code position in claims on readmission rate estimates

BACKGROUND

Suicidal ideation (SI) is a major health concern in children, adolescents, and young adults (CAYA) population. Inaccurate estimates of SI-related hospital readmission rates may contribute to inappropriate allocation of resources for the prevention of future readmissions. The estimation of these readmission rates using claims data may be sensitive to the diagnosis code position used to establish analytic cohorts.

OBJECTIVE

To examine the prevalence and effects of SI diagnosis code position in claims on 30-day readmission rates using the Nationwide Readmissions Database (NRD).

METHODS

This was a cross-sectional study using the NRD (2010-2015). We established six cohorts of hospitalized CAYA (5-24 years old) with a diagnosis of SI based on different combinations of SI diagnosis code (ICD-9 code V62.84) positions in claims. Thirty-day hospital readmission rates following an index SI discharge were estimated for each cohort. We tested the null hypothesis that hospital readmission rates following an index SI discharge are not sensitive to diagnosis code positions using a test for equality of proportions between the predefined SI cohorts.

RESULTS

The prevalence of SI diagnosis codes increased yearly from 2.9% in 2010 to 5.8% in 2015. SI hospital readmission rates ranged from 0 to 41.1 per 1000 index events based on cohort definitions (i.e. diagnosis code positions). We rejected the null hypothesis that SI-related readmission rates are not sensitive to diagnosis code positions.

CONCLUSION

SI-related readmission rate estimates are sensitive to SI diagnosis code positions. Determining appropriate diagnostic positions can further improve readmission analyses for SI and its applications in healthcare policies.

Characteristics, Treatment Patterns, and Economic Outcomes of Patients Initiating Injectable Medications for Management of Type 2 Diabetes Mellitus in Japan: Results from a Retrospective Claims Database Analysis

INTRODUCTION

This study's objective was to describe characteristics, treatment patterns, and economic outcomes of type 2 diabetes mellitus (T2DM) patients initiating injectable antidiabetic medications in Japan.

METHODS

Adults (≥ 18 years) with T2DM, ≥ 2 claims for injectable antidiabetics between 1 August 2011 and 31 July 2015 (first claim = index date), no evidence of type 1 diabetes mellitus, ≤ 1 claim for insulin, no claims for GLP-1RA before index, and continuous enrollment for 6 months before (baseline) and 12 months after index (follow-up) were selected from the Japan Medical Center Database. Patient characteristics and outcomes during the baseline and follow-up periods were described overall and by provider, using the proxy setting of index medication [hospital (including outpatient departments) for specialists; clinic for general practitioner (GP)].

RESULTS

Of the 2683 patients included (mean age: 50 years, 67% male), 1879 (70%) initiated injectable antidiabetics with specialists and 804 (30%) with GPs. The specialist cohort had a significantly greater comorbidity burden, but lower HbA1c levels during baseline, and was more likely to receive intensified treatment at index than the GP cohort. Almost 40% of patients (almost 30% of GP cohort) did not use antidiabetics during baseline; the remaining patients received oral medications, primarily from GPs. During follow-up, patients used the index medication for approximately 7 months. Independent of specialist vs. GP setting, patients received antidiabetics and medications for T2DM-related comorbidities and complications during the baseline and follow-up periods from the same provider, primarily GPs. The overall average healthcare costs were ¥350,404 during baseline and ¥1,856,727 during follow-up.

CONCLUSIONS

In Japan, most T2DM patients initiated injectable antidiabetics with specialists vs. GPs. There were considerable differences in characteristics of patients treated by specialists vs. GPs. After initiation, injectable antidiabetics were largely prescribed by GPs. Future research should evaluate the factors associated with different provider practices and communication channels between specialists and GPs to improve patient management.

FUNDING

Eli Lilly and Co.

Cost-effectiveness of a New Opportunistic Screening Strategy for Walk-in Fingertip HbA1c Testing at Community Pharmacies in Japan

OBJECTIVE

A new opportunistic community-based strategy was launched in Japan in April 2014 to detect lifestyle-related diseases, including diabetes, by creating Specimen Measurement Offices (SMOs). SMOs offer walk-in fingertip HbA_1c testing. This article aimed to assess the value-for-money of HbA_1c testing services at SMOs by conducting a cost-effectiveness analysis.

RESEARCH DESIGN AND METHODS

We compared two scenarios: 1) status quo, defined as HbA_1c testing that is available only through conventional screening, and 2) HbA_1c testing available at SMOs as a complement to the status quo scenario. The model consisted of a screening module with a decision tree and a disease progression module with a Markov model. We calculated incremental cost-effectiveness ratios (i.e., cost per quality-adjusted life-years [QALYs]) over the lifetime analytic horizon as the primary end point of the cost-effectiveness analysis. In this model, we assumed the participant cohort to be people 40-74 years of age who sought walk-in fingertip HbA_1c testing at SMOs on the premises of community pharmacies. Costs and outcomes were discounted at a rate of 3%. The cost-effectiveness was analyzed from a societal perspective.

RESULTS

The incremental cost per individual for those 40-74 years of age was estimated to be -527 U.S. dollars (USD) (-52,722 Japanese yen [JPY]) for HbA_1c testing at SMOs compared with the status quo. Incremental effectiveness was estimated to be 0.0203 QALYs for HbA_1c testing at SMOs compared with the status quo. Therefore, this cost-effectiveness analysis showed that compared with the status quo, HbA_1c testing at SMOs was more effective and had lower cost for the population studied.

CONCLUSIONS

We consider our results to be robust because most simulations were under the threshold of USD 50,000 (JPY 5,000,000) per QALYs gained, by sensitivity analysis. These results will be useful to managers of pharmacies or other health institutions and/or policy makers in local government.

The cost-effectiveness of dulaglutide versus insulin glargine for the treatment of type 2 diabetes mellitus in Japan

AIMS

Dulaglutide is a new once weekly glucagon-like peptide-1 (GLP-1) receptor agonist administered via a disposable auto-injection pen for the management of type 2 diabetes mellitus (T2DM). The objective of this study was to estimate the cost-effectiveness of dulaglutide vs insulin glargine for the management of T2DM from a Japanese healthcare perspective, in accordance with recently approved Japanese Cost-Effectiveness Guidelines.

METHODS

The IQVIA CORE Diabetes Model (version 9) was used to estimate the long-term costs and effects of treatment with dulaglutide and insulin glargine. Direct comparative data from the Araki 2015 trial (NCT01584232) was used to inform the analysis. Costs associated with treatment and complications were derived from Japanese sources wherever possible and inflated to 2015 Japanese Yen (JPY). Utilities were based upon a European systematic review of diabetes utilities and adjusted for use in a Japanese population. One-way and probabilistic sensitivity analyses (OWSA and PSA) were conducted on all inputs and key modeling assumptions.

RESULTS

Dulaglutide 0.75 mg was associated with higher quality-adjusted life years (QALYs), life years (LYs), and total costs, compared to insulin glargine, resulting in an incremental cost-effectiveness ratio (ICER) of 416,280 JPY/QALY gained. Treatment with dulaglutide increased the time alive and free from diabetes-related complications by 4 months. OWSA and PSA indicated that results were robust to plausible variations in input parameters and modeling assumptions.

LIMITATIONS

Key limitations of this study are similar to other cost-utility analyses of diabetes, including the extrapolation of short-term clinical trial data into lifelong durations. In addition, due to the lack of robust published Japanese data, some values were derived from non-Japanese sources.

CONCLUSIONS

This analysis suggests that dulaglutide 0.75 mg may be a cost-effective treatment alternative to insulin glargine for patients with T2DM in Japan.