The Health Economic Value of Changes in Glycaemic Control, Weight and Rates of Hypoglycaemia in Type 1 Diabetes Mellitus

Adverse drug events in cost-effectiveness models of pharmacological interventions for diabetes, diabetic retinopathy, and diabetic macular edema: a scoping review

OBJECTIVE

The objective of this review was to examine the role of adverse drug events (ADEs) caused by pharmacological interventions in cost-effectiveness models for diabetes mellitus, diabetic retinopathy, and diabetic macular edema.

INTRODUCTION

Guidelines for economic evaluation recognize the importance of including ADEs in the analysis, but in practice, consideration of ADEs in cost-effectiveness models seem to be vague. Inadequate inclusion of these harmful outcomes affects the reliability of the results, and the information provided by economic evaluation could be misleading. Reviewing whether and how ADEs are incorporated in cost-effectiveness models is necessary to understand the current practices of economic evaluation.

INCLUSION CRITERIA

Studies included were published between 2011-2022 in English, representing cost-effectiveness analyses using modeling framework for pharmacological interventions in the treatment of diabetes mellitus, diabetic retinopathy, or diabetic macular edema. Other types of analyses and other types of conditions were excluded.

METHODS

The databases searched included MEDLINE (PubMed), CINAHL (EBSCOhost), Scopus, Web of Science Core Collection, and NHS Economic Evaluation Database. Gray literature was searched via the National Institute for Health and Care Excellence, European Network for Health Technology Assessment, the National Institute for Health and Care Research, and the International Network of Agencies for Health Technology Assessment. The search was conducted on January 1, 2023. Titles and abstracts were screened for inclusion by 2 independent reviewers. Full-text review was conducted by 3 independent reviewers. A data extraction form was used to extract and analyze the data. Results were presented in tabular format with a narrative summary, and discussed in the context of existing literature and guidelines.

RESULTS

A total of 242 reports were extracted and analyzed in this scoping review. For the included analyses, type 2 diabetes was the most common disease (86%) followed by type 1 diabetes (10%), diabetic macular edema (9%), and diabetic retinopathy (0.4%). The majority of the included analyses used a health care payer perspective (88%) and had a time horizon of 30 years or more (75%). The most common model type was a simulation model (57%), followed by a Markov simulation model (18%). Of the included cost-effectiveness analyses, 26% included ADEs in the modeling, and 13% of the analyses excluded them. Most of the analyses (61%) partly considered ADEs; that is, only 1 or 2 ADEs were included. No difference in overall inclusion of ADEs between the different conditions existed, but the models for diabetic retinopathy and diabetic macular edema more often omitted the ADE-related impact on quality of life compared with the models for diabetes mellitus. Most analyses included ADEs in the models as probabilities (55%) or as a submodel (40%), and the most common source for ADE incidences were clinical trials (65%).

CONCLUSIONS

The inclusion of ADEs in cost-effectiveness models is suboptimal. The ADE-related costs were better captured than the ADE-related impact on quality of life, which was most pronounced in the models for diabetic retinopathy and diabetic macular edema. Future research should investigate the potential impact of ADEs on the results, and identify the criteria and policies for practical inclusion of ADEs in economic evaluation.

Estimating the value of sodium-glucose cotransporter-2 inhibitors within the context of contemporary guidelines and the totality of evidence

AIMS

To comprehensively estimate the cost-effectiveness of sodium glucose cotransporter-2 (SGLT2) inhibitor usage in the management of type 2 diabetes mellitus (T2DM) at established clinical review points, incorporating the totality of proven health benefits.

MATERIALS AND METHODS

This study considered the cardio- and reno-protective effects of SGLT2 inhibitors using the Cardiff type 2 diabetes model. Conventional cost-effectiveness evaluations were undertaken for eligible populations at relevant intensification points reflecting the 2022 guidelines versus the 2015 National Institute of Health and Care Excellence (NICE) guidelines; incremental cost-effectiveness ratio lifetime trajectories and timepoints for complete cost-offset were estimated for each pathway. Treatment effects, utility decrements and costs (applied additively and discounted at 3.5%) were sourced from the published literature.

RESULTS

For all subpopulations on treatment pathways reflecting the NG28-2022 guidelines, SGLT2 inhibitor introduction was cost-effective, becoming cost-saving between 2 and 16 years post-initiation. Despite increases in pharmacy costs, predicted lifetime costs were lower than for pathways reflecting the NG28-2015 guidelines, driven by a reduction in heart failure hospitalization and chronic kidney disease costs. Incremental gains in quality-adjusted life years (ranging from 0.58-1.12) resulted in dominance for the updated NG28-2022 guidance in all scenarios.

CONCLUSIONS

Our results show that SGLT2 inhibitors have the potential to lower healthcare costs while improving health outcomes in eligible patient subpopulations.

A Review of Economic Models Submitted to NICE's Technology Appraisal Programme, for Treatments of T1DM & T2DM

Background: In the UK, 4.7 million people are currently living with diabetes. This is projected to increase to 5 million by 2025. The direct and indirect costs of T1DM and T2DM are rising, and direct costs already account for approximately 10% of the National Health Service (NHS) budget.

Objective: The aim of this review is to assess the economic models used in the context of NICE’s Technology Appraisals (TA) Programme of T1DM and T2DM treatments, as well as to examine their compliance with the American Diabetes Association’s (ADA) guidelines on computer modelling.

Methods: A review of the economic models used in NICE’s TA programme of T1DM and T2DM treatments was undertaken. Relevant TAs were identified through searching the NICE website for published appraisals completed up to April 2021. The review also examined the associated Evidence Review Group (ERG) reports and Final Appraisal Documents (FAD), which are publicly accessible. ERG reports were scrutinised to identify major issues pertaining to the economic modelling. The FAD documents were then examined to assess how these issues reflected on NICE recommendations.

Results: Overall, 10 TAs pertaining to treatments of T1DM and T2DM were identified. Two TAs were excluded as they did not use economic models. Seven of the 8 included TAs related to a novel class of oral antidiabetic drugs (OADs), gliflozins, and one to continuous subcutaneous insulin infusion (CSII) devices. There is a lack of recent, robust data informing risk equations to enable the derivation of transition probabilities. Despite uncertainty surrounding its clinical relevance, bodyweight/BMI is a key driver in many T2DM-models. HbA1c’s reliability as a predictor of hard outcomes is uncertain, chiefly for macrovascular complications. The external validity of T1DM is even less clear. There is an inevitable trade-off between the sophistication of models’ design, their transparency and practicality.

Conclusion: Economic models are essential tools to support decision-making in relation to market access and ascertain diabetes technologies’ cost effectiveness. However, key structural and methodological issues exist. Models’ shortcomings should be acknowledged and contextualised within the framework of technology appraisals. Diabetes medications and other technologies should also be subject to regular and consistent re-appraisal to inform disinvestment decisions. Artificial intelligence could potentially enhance models’ transparency and practicality.

Cost-effectiveness of dapagliflozin as an adjunct to insulin for the treatment of type 1 diabetes mellitus in the United Kingdom

AIMS

To assess the cost-effectiveness of dapagliflozin, a sodium-glucose co-transporter-2 (SGLT2) inhibitor, as an adjunct to insulin in adults with type 1 diabetes mellitus (T1DM) inadequately controlled by insulin alone in the UK setting.

METHODS

A cost-utility analysis was conducted to compare dapagliflozin (5 mg or 10 mg) added to insulin versus insulin monotherapy (standard of care) over a lifetime horizon. Treatment efficacy and safety data were obtained from 52-week results of the DEPICT-1 and DEPICT-2 trials and a network meta-analysis of SGLT2 inhibitors in T1DM. Direct healthcare costs, life-years, and quality-adjusted life-years (QALYs) were estimated from a UK payer perspective and discounted at 3.5% annually, using the Cardiff T1DM Model. Sensitivity analyses assessed uncertainty in estimated incremental cost-effectiveness ratios (ICERs).

RESULTS

Dapagliflozin 5 mg was associated with gains of 0.23 life-years and 0.42 QALYs, at an additional cost of £4240 per person; corresponding to an ICER of £10 143 versus standard of care. For dapagliflozin 10 mg, incremental life-years, QALYs and costs were 0.24, 0.49 and £2964, respectively; corresponding to an ICER of £6103 versus standard of care. In probabilistic sensitivity analysis, ICER estimates fell below £20 000/QALY in 78% to 90% of simulations. Cost-effectiveness results were sensitive to changes in baseline patient characteristics and treatment effects on glycated haemoglobin; however, ICERs remained below £20 000.

CONCLUSIONS

At cost-effectiveness thresholds conventionally applied in the UK, dapagliflozin as an adjunct to insulin appears to be a cost-effective treatment option for people with T1DM inadequately controlled by insulin alone.

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.

Artificial Pancreas as an Effective and Safe Alternative in Patients with Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis

INTRODUCTION

Insulin injection is the main treatment in patients with type 1 diabetes mellitus (T1DM). Even though continuous glucose monitoring has significantly improved the conditions of these patients, limitations still exist. To further enhance glucose control in patients with T1DM, an artificial pancreas has been developed. We aimed to systematically compare artificial pancreas with its control group during a 24-h basis in patients with T1DM.

METHODS

Electronic databases were carefully searched for English publications comparing artificial pancreas with its control group. Overall daytime and nighttime glucose parameters were considered as the endpoints. Data were evaluated by means of weighted mean differences (WMDs) and 95% confidence intervals (CIs) generated by RevMan 5.3 software.

RESULTS

A total number of 354 patients were included. Artificial pancreas significantly maintained a better mean concentration of glucose (WMD - 1.03, 95% CI - 1.32 to - 0.75; P = 0.00001). Time spent in the hypoglycemic phase was also significantly lower (WMD - 1.23, 95% CI - 1.56 to - 0.91; P = 0.00001). Daily insulin requirement also significantly favored artificial pancreas (WMD - 3.43, 95% CI - 4.27 to - 2.59; P = 0.00001). Time spent outside the euglycemic phase and hyperglycemia phase (glucose > 10.0 mmol/L) also significantly favored artificial pancreas. Also, the numbers of hypoglycemic events were not significantly different.

CONCLUSION

Artificial pancreas might be considered an effective and safe alternative to be used during a 24-h basis in patients with T1DM.

Assessing the economic value of maintained improvements in Type 1 diabetes management, in terms of HbA1c , weight and hypoglycaemic event incidence

AIMS

Insulin therapy is indicated for people with Type 1 diabetes mellitus; however, treatment-related weight gain and hypoglycaemia represent barriers to optimal glycaemic management. This study assessed the health economic value of maintained reductions in HbA_1c , BMI and hypoglycaemia incidence among the UK Type 1 diabetes population.

METHODS

The Cardiff Type 1 Diabetes Model was used to estimate lifetime costs, life-years and quality-adjusted life-years (QALYs) for individuals with Type 1 diabetes at different baseline HbA_1c , BMI and hypoglycaemic event rates. Results were discounted at 3.5%, and the net monetary benefit associated with improving Type 1 diabetes management was derived at £20 000/QALY gained. Per-person outputs were inflated to national levels using UK Type 1 diabetes prevalence estimates.

RESULTS

Modelled subjects with an HbA_1c of 86 mmol/mol (10.0%) were associated with discounted lifetime per-person costs of £23 795; £12 649 of which may be avoided by maintaining an HbA_1c of 42 mmol/mol (6.0%). Combined with estimated QALY gains of 2.80, an HbA_1c of 42 mmol/mol (6.0%) vs. 86 mmol/mol (10.0%) was associated with a £68 621 per-person net monetary benefit. Over 1 year, unit reductions in BMI produced £120 per-person net monetary benefit, and up to £197 for the avoidance of one non-severe hypoglyceamic event.

CONCLUSIONS

Maintained reductions in HbA_1c significantly alleviate the burden associated with Type 1 diabetes in the UK. Given the influence of weight and hypoglycaemia on health economic outcomes, they must also be key considerations when assessing the value of Type 1 diabetes technologies in clinical practice.

Different Methods for Modelling Severe Hypoglycaemic Events: Implications for Effectiveness, Costs and Health Utilities

BACKGROUND

Clinical trials report severe hypoglycaemic events as the number of patients with at least one event out of the total randomised or number of events for a given total exposure. Different network meta-analysis models have been used to analyse these different data types.

OBJECTIVE

This aim of this article was to establish the impact of using the different models on effectiveness, costs and health utility estimates.

METHODS

We analysed a dataset used in a recent network meta-analysis of severe hypoglycaemic events conducted to inform National Institute for Health and Care Excellence recommendations regarding basal insulin choice for patients with type 1 diabetes mellitus. We fitted a model with a binomial likelihood reporting odds ratios (using a logit link) or hazard ratios (complementary log-log link), a model with a Poisson likelihood reporting hazard ratios and a shared-parameter model combining different types of data. We compared the results in terms of relative effects and resulting cost and disutility estimates.

RESULTS

Relative treatment effects are similar regardless of which model or scale is used. Differences were seen in the probability of having an event on the baseline treatment with the logit model giving a baseline probability of 0.07, the complementary log-log 0.17 and the Poisson 0.29. These translate into differences of up to £110 in the yearly cost of a hypoglycaemic event and 0.004 in disutility.

CONCLUSION

While choice of network meta-analysis model does not have a meaningful impact on relative effects for this outcome, care should be taken to ensure that the baseline probabilities used in an economic model are accurate to avoid misrepresenting costs and effects.

Islet Microencapsulation: Strategies and Clinical Status in Diabetes

PURPOSE OF REVIEW

Type 1 diabetes mellitus (T1DM) is an autoimmune disease that results from the destruction of insulin-producing pancreatic β cells in the islets of Langerhans. Islet cell transplantation has become a successful therapy for specific patients with T1DM with hypoglycemic unawareness. The reversal of T1DM by islet transplantation is now performed at many major medical facilities throughout the world. However, many challenges must still be overcome in order to achieve continuous, long-term successful transplant outcomes. Two major obstacles to this therapy are a lack of islet cells for transplantation and the need for life-long immunosuppressive treatment. Microencapsulation is seen as a technology that can overcome both these limitations of islet cell transplantation. This review depicts the present state of microencapsulated islet transplantation.

RECENT FINDINGS

Microencapsulation can play a significant role in overcoming the need for immunosuppression and lack of donor islet cells. This review focuses on microencapsulation and the clinical status of the technology in combating T1DM.