Performance of the UK Prospective Diabetes Study Outcomes Model 2 in a Contemporary UK Type 2 Diabetes Trial Cohort

Glucose Lowering through Weight management (GLoW): a randomised controlled trial of the clinical and cost effectiveness of a diabetes education and behavioural weight management programme vs a diabetes education programme in adults with a recent diagnosis of type 2 diabetes

AIMS/HYPOTHESIS

UK standard care for type 2 diabetes is structured diabetes education, with no effects on HbA1c, small, short-term effects on weight and low uptake. We evaluated whether remotely delivered tailored diabetes education combined with commercial behavioural weight management is cost-effective compared with current standard care in helping people with type 2 diabetes to lower their blood glucose, lose weight, achieve remission and improve cardiovascular risk factors.

METHODS

We conducted a pragmatic, randomised, parallel two-group trial. Participants were adults (≥18 years) with overweight or obesity (BMI≥25 kg/m2) and recently diagnosed with type 2 diabetes (≤3 years), recruited from 159 primary care practices in England. We randomised participants to a tailored diabetes education and behavioural weight management programme (DEW; delivered by Weight Watchers) or to current standard care diabetes education (DE; Diabetes Education and Self Management for Ongoing and Newly Diagnosed [DESMOND] programme), using a computer-generated randomisation sequence in a 1:1 allocation stratified by gender and diabetes duration, unknown to those collecting and analysing the data. Participants could not be blinded due to the nature of the interventions. Participants completed assessments at 0, 6 and 12 months. The primary outcome was 12 month change from baseline in HbA1c. We also assessed bodyweight, blood pressure, cholesterol (total, HDL, LDL), glucose-lowering medication, behavioural measures (physical activity, food intake), psychosocial measures (eating behaviour, diabetes-related quality of life, wellbeing) and within-trial and modelled lifetime cost effectiveness.

RESULTS

We randomised 577 participants (DEW: 289, DE: 288); 398 (69%) completed 12 month follow-up. We found no evidence for an intervention effect on change in HbA1c from baseline to 12 months (difference: -0.84 [95% CI -2.99, 1.31] mmol/mol, p=0.44) or 6 months (-1.83 [-4.05, 0.40] mmol/mol). We found an intervention effect on weight at 6 (-1.77 [-2.86, -0.67] kg) and 12 months (-1.38 [-2.56, -0.19] kg). Participants in DEW had a higher likelihood of achieving diabetes remission than participants in DE (6 months: RR 2.10 [95% CI 1.03, 4.47]; 12 months: RR 2.53 [1.30, 5.16]). DEW was cost-effective compared with DE in within-trial and lifetime analyses, in the latter generating an incremental cost effectiveness ratio of £2290 per quality-adjusted life year gained.

CONCLUSIONS/INTERPRETATION

A commercial behavioural weight management programme combined with remote dietary counselling after diagnosis of type 2 diabetes did not improve HbA1c up to 12 months post intervention in this trial. The intervention could help people achieve weight loss and be cost-effective compared with current standard National Health Service care.

TRIAL REGISTRATION

ISRCTN 18399564 FUNDING: National Institute for Health and Care Research (NIHR; RP-PG-0216-20010), Medical Research Council (MC_UU_00006/6), NIHR Cambridge Biomedical Research Centre (NIHR203312).

The Long-Term Cost-Effectiveness of Oral Semaglutide Versus Lower-Cost Liraglutide in the UK

INTRODUCTION

Glucagon-like peptide-1 (GLP-1) receptor agonists represent efficacious therapies for treating type 2 diabetes. Oral semaglutide is the only orally administered GLP-1 receptor agonist currently available and has been associated with reductions in glycated hemoglobin and body weight versus once-daily injectable liraglutide after 52 weeks in the PIONEER 4 clinical trial. As lower-cost liraglutide formulations have recently been developed, the present analysis evaluated the long-term cost-effectiveness of oral semaglutide 14 mg versus liraglutide 1.8 mg at lower acquisition costs in the UK.

METHODS

The published and validated PRIME Type 2 Diabetes Model was used to project clinical and cost outcomes over patient lifetimes. Baseline cohort characteristics, as well as treatment-specific changes in physiological parameters and hypoglycemia rates, were sourced from PIONEER 4. Patients were modeled to receive oral semaglutide or liraglutide until HbA1c exceeded 8.0% (64 mmol/mol), after which treatment was intensified to basal insulin. Annual disutilities associated with treatment administration were applied to capture the differential impact of a once-daily oral versus once-daily injectable medication on quality of life. Costs, expressed in 2022 pounds sterling (GBP), were calculated from a National Health Service (NHS) perspective. The acquisition cost of liraglutide was reduced by up to 50% at increments of 5% across a range of scenarios.

RESULTS

Oral semaglutide was associated with improved quality-adjusted life expectancy of 0.18 quality-adjusted life years versus liraglutide 1.8 mg due to a reduced incidence of diabetes-related complications and a reduced treatment-administration burden. Direct, per-person complication costs were estimated to be GBP 187 lower with oral semaglutide. Oral semaglutide remained dominant or cost-effective in the majority of scenarios, even with liraglutide price reductions of 50% applied.

CONCLUSIONS

Oral semaglutide 14 mg was projected to be cost-effective versus lower-cost liraglutide 1.8 mg in the UK.

Using QALYs as an Outcome for Assessing Global Prediction Accuracy in Diabetes Simulation Models

OBJECTIVES

(1) To demonstrate the use of quality-adjusted life-years (QALYs) as an outcome measure for comparing performance between simulation models and identifying the most accurate model for economic evaluation and health technology assessment. QALYs relate directly to decision making and combine mortality and diverse clinical events into a single measure using evidence-based weights that reflect population preferences. (2) To explore the usefulness of Q2, the proportional reduction in error, as a model performance metric and compare it with other metrics: mean squared error (MSE), mean absolute error, bias (mean residual), and R2.

METHODS

We simulated all EXSCEL trial participants (N = 14,729) using the UK Prospective Diabetes Study Outcomes Model software versions 1 (UKPDS-OM1) and 2 (UKPDS-OM2). The EXSCEL trial compared once-weekly exenatide with placebo (median 3.2-y follow-up). Default UKPDS-OM2 utilities were used to estimate undiscounted QALYs over the trial period based on the observed events and survival. These were compared with the QALYs predicted by UKPDS-OM1/2 for the same period.

RESULTS

UKPDS-OM2 predicted patients' QALYs more accurately than UKPDS-OM1 did (MSE: 0.210 v. 0.253; Q2: 0.822 v. 0.786). UKPDS-OM2 underestimated QALYs by an average of 0.127 versus 0.150 for UKPDS-OM1. UKPDS-OM2 predictions were more accurate for mortality, myocardial infarction, and stroke, whereas UKPDS-OM1 better predicted blindness and heart disease. Q2 facilitated comparisons between subgroups and (unlike R2) was lower for biased predictors.

CONCLUSIONS

Q2 for QALYs was useful for comparing global prediction accuracy (across all clinical events) of diabetes models. It could be used for model registries, choosing between simulation models for economic evaluation and evaluating the impact of recalibration. Similar methods could be used in other disease areas.

HIGHLIGHTS

Diabetes simulation models are currently validated by examining their ability to predict the incidence of individual events (e.g., myocardial infarction, stroke, amputation) or composite events (e.g., first major adverse cardiovascular event).We introduce Q2, the proportional reduction in error, as a measure that may be useful for evaluating and comparing the prediction accuracy of econometric or simulation models.We propose using the Q2 or mean squared error for QALYs as global measures of model prediction accuracy when comparing diabetes models' performance for health technology assessment; these can be used to select the most accurate simulation model for economic evaluation and to evaluate the impact of model recalibration in diabetes or other conditions.

Cost-utility analysis of once-weekly insulin icodec and once-daily insulin glargine in patients with type 2 diabetes receiving basal-bolus insulin therapy in China

OBJECTIVE

The purpose of this study is to explore the rational pricing range for the once-weekly administration of insulin icodec in the treatment of type 2 diabetes patients in China who have already received basal insulin therapy.

METHODS

The data foundation of this study originates from the ONWARDS 4 clinical trial and research materials on Chinese type 2 diabetes patients. By comprehensively applying cost-utility analysis methods and binary search techniques, the appropriate price positioning of insulin icodec was determined from the perspective of China's healthcare system.

RESULTS

In the long-term treatment simulation, we found that insulin icodec and insulin glargine performed similarly in terms of quality-adjusted life years (QALYs), with 10.15 and 10.07 years, respectively. Although the annual cost of insulin icodec was initially assumed to be equivalent to that of insulin glargine, in-depth analysis revealed that insulin icodec may have higher cost-effectiveness potential. Further price sensitivity analysis indicated that the reasonable cost range of insulin icodec lies between $851.95 and $1358.25. After fine-tuning through univariate sensitivity analysis, this cost range was revised to $784.90 to $1145.96, a conclusion that was robustly validated in subsequent probabilistic sensitivity analysis and scenario simulations.

CONCLUSION

The conclusion drawn from this study is that, with insulin glargine as the cost reference, the economic cost of insulin icodec for Chinese type 2 diabetes patients is expected to range from $784.90 to $1145.96, providing a reference basis for clinical decision-making and healthcare policy formulation.

Adaptation of risk prediction equations for cardiovascular outcomes among patients with type 2 diabetes in real-world settings: a cross-institutional study using common data model approach

OBJECTIVE

To adapt risk prediction equations for myocardial infarction (MI), stroke, and heart failure (HF) among patients with type 2 diabetes in real-world settings using cross-institutional electronic health records (EHRs) in Taiwan.

METHODS

The EHRs from two medical centers, National Cheng Kung University Hospital (NCKUH; 11,740 patients) and National Taiwan University Hospital (NTUH; 20,313 patients), were analyzed using the common data model approach. Risk equations for MI, stroke, and HF from UKPDS-OM2, RECODe, and CHIME models were adapted for external validation and recalibration. External validation was assessed by (1) discrimination, evaluated by the area under the receiver operating characteristic curve (AUROC) and (2) calibration, evaluated by calibration slopes and intercepts and the Greenwood-Nam-D'Agostino (GND) test. Recalibration was conducted for unsatisfactory calibration (p-value of GND test < 0.05) by adjusting the baseline hazards of original equations to address variations in patients' cardiovascular risks across institutions.

RESULTS

The CHIME risk equations had acceptable discrimination (AUROC: 0.71-0.79) and better calibration than that for UKPDS-OM2 and RECODe, although the calibration remained unsatisfactory. After recalibration, the calibration slopes/intercepts of the CHIME-MI, CHIME-stroke, and CHIME-HF risk equations were 0.9848/- 0.0008, 1.1003/- 0.0046, and 0.9436/0.0063 in the NCKUH population and 1.1060/- 0.0011, 0.8714/0.0030, and 1.0476/- 0.0016 in the NTUH population, respectively. All the recalibrated risk equations showed satisfactory calibration (p-values of GND tests ≥ 0.05).

CONCLUSIONS

We provide valid risk prediction equations for MI, stroke, and HF outcomes in Taiwanese type 2 diabetes populations. A framework for adapting risk equations across institutions is also proposed.

Bariatric Surgery for Adults With Class I Obesity and Difficult-to-Manage Type 2 Diabetes: A Health Technology Assessment

Background

Many individuals with type 2 diabetes are classified as either overweight or obese. A patient may be described as having difficult-to-manage type 2 diabetes if their HbA1c levels remain above recommended target levels, despite efforts to treat it with lifestyle changes and pharmacotherapy. Bariatric surgery refers to procedures that modify the gastrointestinal tract. In patients with class II or III obesity, bariatric surgery has resulted in substantial weight loss, improved quality of life, reduced mortality risk, and resolution of type 2 diabetes. There is some evidence suggesting these outcomes may also be possible for patients with class I obesity as well. We conducted a health technology assessment of bariatric surgery for adults with class I obesity and difficult-to-manage type 2 diabetes, which included an evaluation of effectiveness, safety, cost-effectiveness, the budget impact of publicly funding bariatric surgery, and patient preferences and values.

Methods

We performed a systematic clinical literature review. We assessed the risk of bias of each included study, using the Cochrane Risk of Bias tool for randomized controlled trials, the Risk of Bias in Non-randomized Studies - of Interventions (ROBINS-I) tool for cohort studies, and the Risk of Bias in Systematic Reviews (ROBIS) tool for systematic reviews; we assessed the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic economic literature review and conducted a cost-utility analysis of bariatric surgery in comparison with nonsurgical usual care over a lifetime horizon from a public payer perspective. We also analyzed the budget impact of publicly funding bariatric surgery for adults with class I obesity and difficult-to-manage type 2 diabetes in Ontario. To contextualize the potential value of bariatric surgery, we spoke with people with obesity and type 2 diabetes who had undergone or were considering this procedure.

Results

We included 14 studies in the clinical evidence review. There were large increases in diabetes remission rates (GRADE: Low to Very low) and large reductions in body mass index (GRADE: Low to Very low) with bariatric surgery than with medical management. Bariatric surgery may also reduce the use of medications for type 2 diabetes (GRADE: Low) and may improve quality of life for people with class I obesity and difficult-to-manage type 2 diabetes compared with medical management. (GRADE: Low)Our economic evidence review included 5 cost-effectiveness studies; none were conducted in a Canadian setting, and 4 were considered partially applicable to our research question. Most studies found bariatric surgery to be cost-effective compared to standard care for patients with class I obesity and type 2 diabetes; however, the applicability of these results to the Ontario context is uncertain due to potential differences in clinical practice, resource utilization, and unit costs.Our primary economic evaluation found that over a lifetime horizon, bariatric surgery was more costly (incremental cost: $8,151 per person) but also more effective than current usual care (led to a 0.339 quality-adjusted life-year [QALY] gain per person). The cost increase was driven by costs associated with surgery (before, after, and during surgery), and the QALY gain was due to life-years gained. Results were sensitive to the bariatric surgery cost and assumptions regarding its long-term benefits with respect to weight loss and diabetes remission.Publicly funding 50 bariatric surgeries in year 1, and gradually increasing to 250 surgeries in year 5, for people with class I obesity and difficult-to-manage type 2 diabetes would lead to budget increases of $0.55 million in year 1 to $2.45 million in year 5, for a total of $7.63 million over 5 years.The people with obesity and type 2 diabetes with whom we spoke reported that bariatric surgery was generally seen as a positive treatment option, and those who had undergone the procedure reported positively on its value as a treatment to manage their weight and diabetes.

Conclusions

For adults with class I obesity and difficult-to-manage type 2 diabetes, bariatric surgery may be more clinically effective and cost-effective than medical management. Compared with medical management in people with class I obesity and difficult-to-manage type 2 diabetes, bariatric surgery may result in large increases in diabetes remission rates, large reductions in BMI, and reduced medication use for type 2 diabetes, improved quality of life. Over a lifetime horizon, bariatric surgery led to a cost increase and QALY gain. Bariatric surgery can result in postsurgical complications that are not faced by those receiving medical management. The cost-effectiveness of bariatric surgery depends on its long-term impacts on obesity-related and diabetes-related complications, which could be uncertain.Our budget impact analysis suggests that publicly funding bariatric surgery in Ontario for people with class I obesity and difficult-to-manage type 2 diabetes would lead to a budget increase of $7.63 million over 5 years.For people with obesity and type 2 diabetes, bariatric surgery was seen as a potential positive treatment option to manage their weight and diabetes.

Prognostic models for heart failure in patients with type 2 diabetes: a systematic review and meta-analysis

OBJECTIVE

To provide a systematic review, critical appraisal, assessment of performance and generalisability of all the reported prognostic models for heart failure (HF) in patients with type 2 diabetes (T2D).

METHODS

We performed a literature search in Medline, Embase, Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and Scopus (from inception to July 2022) and grey literature to identify any study developing and/or validating models predicting HF applicable to patients with T2D. We extracted data on study characteristics, modelling methods and measures of performance, and we performed a random-effects meta-analysis to pool discrimination in models with multiple validation studies. We also performed a descriptive synthesis of calibration and we assessed the risk of bias and certainty of evidence (high, moderate, low).

RESULTS

Fifty-five studies reporting on 58 models were identified: (1) models developed in patients with T2D for HF prediction (n=43), (2) models predicting HF developed in non-diabetic cohorts and externally validated in patients with T2D (n=3), and (3) models originally predicting a different outcome and externally validated for HF (n=12). RECODe (C-statistic=0.75 95% CI (0.72, 0.78), 95% prediction interval (PI) (0.68, 0.81); high certainty), TRS-HFDM (C-statistic=0.75 95% CI (0.69, 0.81), 95% PI (0.58, 0.87); low certainty) and WATCH-DM (C-statistic=0.70 95% CI (0.67, 0.73), 95% PI (0.63, 0.76); moderate certainty) showed the best performance. QDiabetes-HF demonstrated also good discrimination but was externally validated only once and not meta-analysed.

CONCLUSIONS

Among the prognostic models identified, four models showed promising performance and, thus, could be implemented in current clinical practice.

The challenges and pitfalls of incorporating evidence from cardiovascular outcomes trials in health economic modelling of type 2 diabetes

The clinical evidence base for evaluating modern type 2 diabetes interventions has expanded greatly in recent years, with numerous efficacious treatment options available (including dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter-2 inhibitors). The cardiovascular safety of these interventions has been assessed individually versus placebo in numerous cardiovascular outcomes trials (CVOTs), statistically powered to detect differences in a composite endpoint of major adverse cardiovascular events. There have been growing calls to incorporate these data in the long-term modelling of type 2 diabetes interventions because current diabetes models were developed prior to the conduct of the CVOTs and therefore rely on risk equations developed in the absence of these data. However, there are numerous challenges and pitfalls to avoid when using data from CVOTs. The primary concerns are around the heterogeneity of the trials, which have different study durations, inclusion criteria, rescue medication protocols and endpoint definitions; this results in significant uncertainty when comparing two or more interventions evaluated in separate CVOTs, as robust adjustment for these differences is difficult. Analyses using CVOT data inappropriately can dilute clear evidence from head-to-head clinical trials, and blur healthcare decision making. Calibration of existing models may represent an approach to incorporating CVOT data into diabetes modelling, but this can only offer a valid comparison of one intervention versus placebo based on a single CVOT. Ideally, model development should utilize patient-level data from CVOTs to prepare novel risk equations that can better model modern therapies for type 2 diabetes.

The WISDOM self-management intervention: A cost-effectiveness analysis to support the transformation of type 2 diabetes care in England

OBJECTIVES

To assess the cost-effectiveness of the WISDOM self-management intervention for type 2 diabetes compared with care as usual.

DESIGN

We performed a difference-in-differences analysis to estimate differences in risk factors for diabetes complications between people in the WISDOM group (n = 25, 276) and a control group (n = 15, 272) using GP records. A decision analytic model was then used to extrapolate differences in risk factors into costs and outcomes in the long term.

SETTING

Participating GP practices in West Hampshire and Southampton, UK.

PARTICIPANTS

All people diagnosed with type 2 diabetes between January 1990 and March 2020 (n = 40,548).

OUTCOMES

Diabetes-related complications, quality-adjusted life years (QALYs) and costs to the English National Health Service at 5 years and lifetime.

INTERVENTIONS

The WISDOM intervention included risk stratification, self-management education programme to professionals and people with type 2 diabetes, and monitoring of key treatment targets.

RESULTS

WISDOM was associated with less atrial fibrillation [p = 0.001], albuminuria [p = 0.002] and blood pressure [p = 0.098]. Among all people in the intervention group, WISDOM led to 51 [95%CI: 25; 76] QALYs gained and saved £278,036 [95%CI: -631,900; 176,392] in the first 5 years after its implementation compared with care as usual. During those people' lifetime, WISDOM led to 253 [95%CI: 75; 404] QALYs gained and cost saving of £126,380 [95%CI: -1,466,008; 1,339,628]. The gains in QALYs were a result of reduced diabetes-related complications through improved management of the associated risk factors.

CONCLUSIONS

The WISDOM risk-stratification and education intervention for type 2 diabetes appear to be cost-effective compared to usual care by reducing diabetes complications.

Insulin degludec/liraglutide versus its monotherapy on T2D patients: A lifetime cost-utility analysis in China

Introduction: IDegLira (brand name Xultophy) is a novel fixed ratio combination of insulin degludec and liraglutide for type 2 diabetes (T2D) patients. This study aimed to investigate the lifetime cost-effective value of IDegLira compared with its single component (Degludec or Liraglutide) and to explore the suitable annual cost of IDegLira if necessary. Methods: UKPDS OM2 was applied to determine the long-term quality-adjusted life years (QALYs) and total costs. The efficacy data that were inputted into the model were synthesized from 6 randomized clinical trials (RCTs) that directly assessed the clinical benefit of IDegLira and its components in the treatment of uncontrolled T2D patients. The economic results were examined by one-way sensitivity analysis (OSA) and probabilistic sensitivity analysis (PSA). Further price reduction of IDegLira was investigated by binary search. Results: The IDegLira, IDeg, and Lira yielded 11.79 QALYs, 11.62 QALYs, and 11.73 QALYs and total cost of $20281.61, $3726.76, and $11941.26, respectively. The incremental cost-utility ratio (ICUR) of IDegLira versus IDeg was $99464.12/QALYs, and the ICUR of IDegLira versus Lira was $143348.26/QALYs, which indicated that IDegLira was not a cost-effective therapy for T2D patients compared with its components at the current price from a Chinese national healthcare system perspective. Base case results were robust to OSA and PSA. A further binary search showed that IDegLira appears to only be cost-effective if the annual cost of IDegLira is decreased by 58% when IDeg is considered as a reference, or by 30.57% when Lira is considered as a reference. Conclusion: In conclusion, IDegLira appears to not be cost-effective when compared with the current prices of IDeg or Lira for T2D patients in China. However, after the binary search, IDegLira appears to only be cost-effective if the annual cost of IDegLira is decreased 58% when IDeg is considered as a reference, or by 30.57% when Lira is considered as a reference.