Burden of cardiovascular risk factors and disease among patients with type 1 diabetes: results of the Australian National Diabetes Audit (ANDA)

Evaluating the Cost-Utility of Continuous Glucose Monitoring in Individuals with Type 1 Diabetes: A Systematic Review of the Methods and Quality of Studies Using Decision Models or Empirical Data

INTRODUCTION

This review presents a critical appraisal of differences in the methodologies and quality of model-based and empirical data-based cost-utility studies on continuous glucose monitoring (CGM) in type 1 diabetes (T1D) populations. It identifies key limitations and challenges in health economic evaluations on CGM and opportunities for their improvement.

METHODS

The review and its documentation adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews. Searches for articles published between January 2000 and January 2023 were conducted using the MEDLINE, Embase, Web of Science, Cochrane Library, and Econlit databases. Published studies using models and empirical data to evaluate the cost utility of all CGM devices used by T1D patients were included in the search. Two authors independently extracted data on interventions, populations, model settings (e.g., perspectives and time horizons), model types and structures, clinical outcomes used to populate the model, validation, and uncertainty analyses. They subsequently met to confirm consensus. Quality was assessed using the Philips checklist for model-based studies and the Consensus Health Economic Criteria (CHEC) checklist for empirical studies. Model validation was assessed using the Assessment of the Validation Status of Health-Economic decision models (AdViSHE) checklist. The extracted data were used to generate summary tables and figures. The study protocol is registered with PROSPERO (CRD42023391284).

RESULTS

In total, 34 studies satisfied the selection criteria, two of which only used empirical data. The remaining 32 studies applied 10 different models, with a substantial majority adopting the CORE Diabetes Model. Model-based studies often lacked transparency, as their assumptions regarding the extrapolation of treatment effects beyond available evidence from clinical studies and the selection and processing of the input data were not explicitly stated. Initial scores for disagreements concerning checklists were relatively high, especially for the Philips checklist. Following their resolution, overall quality scores were moderate at 56%, whereas model validation scores were mixed. Strikingly, costing approaches differed widely across studies, resulting in little consistency in the elements included in intervention costs.

DISCUSSION AND CONCLUSION

The overall quality of studies evaluating CGM was moderate. Potential areas of improvement include developing systematic approaches for data selection, improving uncertainty analyses, clearer reporting, and explaining choices for particular modeling approaches. Few studies provided the assurance that all relevant and feasible options had been compared, which is required by decision makers, especially for rapidly evolving technologies such as CGM and insulin administration. High scores for disagreements indicated that several checklists contained questions that were difficult to interpret consistently for quality assessment. Therefore, simpler but comprehensive quality checklists may be needed for model-based health economic evaluation studies.

Non-coronary arterial outcomes in people with type 1 diabetes mellitus: a Swedish retrospective cohort study

Background

Observational studies on long-term trends, risk factor association and importance are scarce for type 1 diabetes mellitus and peripheral arterial outcomes. We set out to investigate trends in non-coronary complications and their relationships with cardiovascular risk factors in persons with type 1 diabetes mellitus compared to matched controls.

Methods

34,263 persons with type 1 diabetes mellitus from the Swedish National Diabetes Register and 164,063 matched controls were included. Incidence rates of extracranial large artery disease, aortic aneurysm, aortic dissection, lower extremity artery disease, and diabetic foot syndrome were analyzed using standardized incidence rates and Cox regression.

Findings

Between 2001 and 2019, type 1 diabetes mellitus incidence rates per 100,000 person-years were as follows: extracranial large artery disease 296.5-84.3, aortic aneurysm 0-9.2, aortic dissection remained at 0, lower extremity artery disease 456.6-311.1, and diabetic foot disease 814.7-77.6. Persons with type 1 diabetes mellitus with cardiometabolic risk factors at target range did not exhibit excess risk of extracranial large artery disease [HR 0.83 (95% CI, 0.20-3.36)] or lower extremity artery disease [HR 0.94 (95% CI, 0.30-2.93)], compared to controls. Persons with type 1 diabetes with all risk factors at baseline, had substantially elevated risk for diabetic foot disease [HR 29.44 (95% CI, 3.83-226.04)], compared to persons with type 1 diabetes with no risk factors. Persons with type 1 diabetes mellitus continued to display a lower risk for aortic aneurysm, even with three cardiovascular risk factors at baseline [HR 0.31 (95% CI, 0.15-0.67)]. Relative importance analyses demonstrated that education, glycated hemoglobin (HbA1c), duration of diabetes and lipids explained 54% of extracranial large artery disease, while HbA1c, smoking and systolic blood pressure explained 50% of lower extremity artery disease and HbA1c alone contributed to 41% of diabetic foot disease. Income, duration of diabetes and body mass index explained 66% of the contribution to aortic aneurysm.

Interpretation

Peripheral arterial complications decreased in persons with type 1 diabetes mellitus, except for aortic aneurysm which remained low. Besides glycemic control, traditional cardiovascular risk factors were associated with incident outcomes. Risk of these outcomes increased with additional risk factors present. Persons with type 1 diabetes mellitus exhibited a lower risk of aortic aneurysm compared to controls, despite presence of cardiovascular risk factors.

Funding

Swedish Governmental and the county support of research and education of doctors, the Swedish Heart and Lung Foundation, Sweden and Åke-Wibergs grant.

Patient perceptions of cardiovascular risk, lipid management and statins in type 1 diabetes

Lipid-lowering reduces cardiovascular risk in type 1 diabetes (T1D), but dyslipidaemia remains under-recognised and under-treated. Through patient surveys, barriers to lipid management in T1D were identified, including lack of awareness of cardiovascular risk and cholesterol levels, preference for managing glycaemia over lipids, preference for lifestyle modification over pharmacotherapy, and statin side-effect concerns.

Comparison of coronary artery calcium score and cardiovascular risk-stratification by European Society of Cardiology Guidelines and Steno Type 1 Risk Engine in statin-naïve adults with type 1 diabetes

BACKGROUND

Coronary artery calcium (CAC) is a marker of atherosclerotic cardiovascular disease (CVD). However, for patients with type 1 diabetes (T1D), its relationship with T1D-specific cardiovascular (CV) risk-stratification tools is unknown.

AIMS

Assess prevalence of CAC and evaluate relationship between CAC and T1D-specific CV risk-stratification methods in T1D.

METHODS

Cross-sectional study of adults with T1D age 20-60 years, statin-naïve and no history of CVD. Data was obtained from electronic medical records and by interview. Presence of CAC was assessed using non-contrast cardiac computed tomography and quantified by Agatston Units (AU). CV risk-stratification was assessed using the 2019 European Society of Cardiology (ESC) Guidelines and the Steno T1 Risk Engine (ST1RE).

RESULTS

85 patients were included with mean age 35.4 ± 10.3 years, HbA1c 8.3 ± 1.5 % and T1D duration 17.0 ± 10.1 years. 67 patients (78.9 %) had a CAC score of 0 AU, 17 (20.0 %) >0-100 AU, and one (1.2 %) >100 AU. Duration of T1D (p = 0.009), body mass index (p = 0.029), neuropathy (p = 0.016) and low-density lipoprotein cholesterol levels (p = 0.016) were independently associated with a positive CAC score on multivariate analysis. Positive predictive value for a positive CAC score was 85.7 % for the ST1RE high risk category and 31.3 % for the 2019 ESC Guidelines very high risk category.

CONCLUSIONS

One-fifth of this T1D cohort had a positive CAC score. The ST1RE was superior in identifying positive CAC compared to the 2019 ESC Guidelines. Further studies are required to elucidate the role of CAC in personalising CV risk-stratification and statin initiation in T1D.

Lipid-lowering therapies and cardiovascular risk-stratification strategies in adults with type 1 diabetes

PURPOSE OF REVIEW

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of mortality in adults with type 1 diabetes (T1D). Although dyslipidaemia is a modifiable and prevalent risk factor in individuals with T1D, determining when to initiate lipid-lowering therapy for primary prevention of ASCVD can be challenging. In this article, recommendations for lipid-lowering therapy from updated clinical guidelines over the last 5 years, additional risk-stratification methods, hypertriglyceridaemia management and potential barriers to optimal care in adults with T1D are discussed.

RECENT FINDINGS

Low-density lipoprotein cholesterol (LDL-C) is the primary target for lipid-lowering. However, international guidelines recommend differing approaches to ASCVD risk-stratification, lipid-lowering, and LDL-C goals in individuals with diabetes, predominantly reflecting evidence from studies in type 2 diabetes. Despite guideline recommendations, several studies have demonstrated that statins are underused, and LDL-C goals are not attained by many individuals with T1D. Additional risk-stratification methods including T1D-specific ASCVD risk calculators, coronary artery calcium scoring, and lipoprotein(a) may provide additional information to define when to initiate lipid-lowering therapy.

SUMMARY

Clinical trial evidence for lipid-lowering therapies in T1D is lacking, and further studies are needed to inform best practice. Optimization and harmonization of ASCVD risk-stratification and lipid management in individuals with T1D is required.

Mapping care provision for type 1 diabetes throughout Australia: a protocol for a mixed-method study

INTRODUCTION

Type 1 diabetes (T1D) is a chronic and incurable autoimmune disease, diagnosed in early childhood and managed initially in paediatric healthcare services. In many countries, including Australia, national audit data suggest that management and care of T1D, and consequently glycaemic control, are consistently poor. This can lead to adverse outcomes such as cardiovascular disease and nephropathy. T1D treatment is complex, multidisciplinary, multiagency and life-long and should involve patient-centred, developmentally appropriate care. Although an emerging body of literature describes T1D models of care, their components, implementation determinants and associated outcomes are poorly understood.

OBJECTIVES

To provide a study protocol to describe methods to map existing models of care for children and young adults living with T1D. It will identify the gaps and needs in care delivery as viewed by healthcare providers and by children, young people and their families accessing care in metropolitan and rural or remote regions throughout Australia.

METHODS AND ANALYSIS

A mixed-method study that includes provider and consumer-specific surveys and interviews about current T1D care provisions. Data will be analysed thematically (qualitative) and statistically (quantitative) and synthesised to describe the key characteristics of effective and sustainable models of care for T1D and to identify gaps.

ETHICS AND DISSEMINATION

Ethics approval was granted by the Macquarie University Human Research Ethics Committee in July 2022 (#520221154439676). Results will be disseminated via publication in peer-reviewed journals and at relevant conferences.

ANDA-Evaluating Facilitated Feedback Enhancement - a Cluster randomised Trial (ANDA-EFFECT): protocol for a cluster randomised trial of audit feedback augmented with education and support, compared to feedback alone, on acceptability, utility and health outcomes in diabetes centres in Australia

BACKGROUND

People living with diabetes must manage a range of factors for optimal control of glycaemia and to minimise the risk of diabetes-related complications. Diabetes practitioners are expected to follow guidelines for the key process of care and clinical outcomes, to help people living with diabetes achieve clinical targets. In Australia, the performance of diabetes centres against guidelines is evaluated by the Australian National Diabetes Audit, an annual clinical audit and feedback activity. Previous work has identified areas for improvement in the feedback provided to participating diabetes centres and suggested additional educational and support resources to assist in using audit feedback for the development of quality improvement activities. This cluster randomised trial will test the acceptability, utility and impact on selected clinical outcomes of the developed study intervention (audit feedback and a tailored educational and peer support cointervention).

METHODS

Two-armed cluster randomised trial with Australian Diabetes Centres that participated in the Australian National Diabetes Audit in 2021 as the clusters, stratified by location and type of centre. We aim to recruit 35 diabetes centres in each arm. Both the intervention and control arms will receive an augmented feedback report, accompanied by a partially pre-populated slide deck. In addition, the intervention arm will receive a tailored theory-based intervention designed to address identified, modifiable barriers to utilising and implementing the recommendations from diabetes audit feedback. The co-primary outcomes are (1) HbA1c at the patient level, measured at 6 months after delivery of the intervention, and (2) the acceptability and utility of the augmented feedback and cointerventions at the practitioner level, measured at 3 months after delivery of the intervention.

DISCUSSION

This trial aims to test the effects of systematic development and implementation of theory and evidence-informed changes to the audit feedback delivered to diabetes centres participating in an established national clinical diabetes audit. Potential benefits of improved audit feedback include more optimal engagement with the feedback by end clinical users which, ultimately, may lead to improvements in care for people living with diabetes.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry ACTRN12621000765820. Prospectively registered on June 21, 2021.

Nationally Subsidized Continuous Glucose Monitoring: A Cost-effectiveness Analysis

OBJECTIVE

The Continuous Glucose Monitoring (CGM) Initiative recently introduced universal subsidized CGM funding for people with type 1 diabetes under 21 years of age in Australia. We thus aimed to evaluate the cost-effectiveness of this CGM Initiative based on national implementation data and project the economic impact of extending the subsidy to all age-groups.

RESEARCH DESIGN AND METHODS

We used a patient-level Markov model to simulate disease progression for young people with type 1 diabetes and compared government-subsidized access to CGM with the previous user-funded system. Three years of real-world clinical input data were sourced from analysis of the Australasian Diabetes Data Network and National Diabetes Services Scheme registries. Costs were considered from the Australian health care system's perspective. An annual discount rate of 5% was applied to future costs and outcomes. Uncertainty was evaluated with probabilistic and deterministic sensitivity analyses.

RESULTS

Government-subsidized CGM funding for young people with type 1 diabetes compared with a completely user-funded model resulted in an incremental cost-effectiveness ratio (ICER) of AUD 39,518 per quality-adjusted life-year (QALY) gained. Most simulations (85%) were below the commonly accepted willingness-to-pay threshold of AUD 50,000 per QALY gained in Australia. Sensitivity analyses indicated that base-case results were robust, though strongly impacted by the cost of CGM devices. Extending the CGM Initiative throughout adulthood resulted in an ICER of AUD 34,890 per QALY gained.

CONCLUSIONS

Providing subsidized access to CGM for people with type 1 diabetes was found to be cost-effective compared with a completely user-funded model in Australia.

Predictive Value of the Advanced Lipoprotein Profile and Glycated Proteins on Diabetic Retinopathy

This study aimed to assess whether the advanced characteristics of serum lipoprotein subclasses could better predict the risk of developing diabetic retinopathy (DR) and its severity compared to other established risk factors in subjects with type 1 (T1D) and type 2 (T2D) diabetes. This observational, cross-sectional substudy analyzed DR-related data from 309 T1D and 264 T2D subjects. The advanced lipoprotein and glycoprotein profile was determined by nuclear magnetic resonance (NMR) spectroscopy (Liposcale test). NMR analysis of lipoproteins revealed that T1D subjects with DR showed standard non-HDL particles, despite higher IDL lipid concentrations. Notably, IDL lipids were elevated in T1D subjects with worsened DR. VLDL and LDL were smaller, whereas HDL triglycerides were increased in DR compared with non-DR. On the other hand, the T2D subjects with DR showed altered characteristics in the LDL fraction, mainly revealed by a significant decrease in smaller LDL and a reduction in LDL-C. Moreover, the glycoprotein profile did not reveal significant changes among DR groups, regardless of the type of diabetes. However, lipoprotein characteristics and glycoproteins unveiled by NMR analysis did not improve the predictive value of conventional lipids or other traditional, well-established biomarkers of DR in our cohorts.

The Cost of Control: Cost-effectiveness Analysis of Hybrid Closed-Loop Therapy in Youth

OBJECTIVE

Hybrid closed-loop (HCL) therapy is an efficacious management strategy for young people with type 1 diabetes. However, high costs prevent equitable access. We thus sought to evaluate the cost-effectiveness of HCL therapy compared with current care among young people with type 1 diabetes in Australia.

RESEARCH DESIGN AND METHODS

A patient-level Markov model was constructed to simulate disease progression for young people with type 1 diabetes using HCL therapy versus current care, with follow-up from 12 until 25 years of age. Downstream health and economic consequences were compared via decision analysis. Treatment effects and proportions using different technologies to define "current care" were based primarily on data from an Australian pediatric randomized controlled trial. Transition probabilities and utilities for health states were sourced from published studies. Costs were considered from the Australian health care system's perspective. An annual discount rate of 5% was applied to future costs and outcomes. Uncertainty was evaluated with probabilistic and deterministic sensitivity analyses.

RESULTS

Use of HCL therapy resulted in an incremental cost-effectiveness ratio of Australian dollars (AUD) $32,789 per quality-adjusted life year (QALY) gained. The majority of simulations (93.3%) were below the commonly accepted willingness-to-pay threshold of AUD $50,000 per QALY gained in Australia. Sensitivity analyses indicated that the base-case results were robust.

CONCLUSIONS

In this first cost-effectiveness analysis of HCL technologies for the management of young people with type 1 diabetes, HCL therapy was found to be cost-effective compared with current care in Australia.

Early Markers of Cardiovascular Disease Associated with Clinical Data and Autosomal Ancestry in Patients with Type 1 Diabetes: A Cross-Sectional Study in an Admixed Brazilian Population

Patients with type 1 diabetes (T1D) have a higher risk of developing cardiovascular disease (CVD), which is a major cause of death in this population. This study investigates early markers of CVD associated with clinical data and autosomal ancestry in T1D patients from an admixed Brazilian population. A cross-sectional study was conducted with 99 T1D patients. The mean age of the study sample was 27.6 years and the mean duration of T1D was 14.4 years. The frequencies of abnormalities of the early markers of CVD were 19.6% in the ankle-brachial index (ABI), 4.1% in the coronary artery calcium score (CACS), and 5% in the carotid Doppler. A significant percentage of agreement was observed for the comparison of the frequency of abnormalities between CACS and carotid Doppler (92.2%, p = 0.041). There was no significant association between the level of autosomal ancestry proportions and early markers of CVD. The ABI was useful in the early identification of CVD in asymptomatic young patients with T1D and with a short duration of disease. Although CACS and carotid Doppler are non-invasive tests, carotid Doppler is more cost-effective, and both have limitations in screening for CVD in young patients with a short duration of T1D. We did not find a statistically significant relationship between autosomal ancestry proportions and early CVD markers in an admixed Brazilian population.

Exploring HbA1c variation between Australian diabetes centres: The impact of centre-level and patient-level factors

Background

Increasing global diabetes incidence has profound implications for health systems and for people living with diabetes. Guidelines have established clinical targets but there may be variation in clinical outcomes including HbA1c, based on location and practice size. Investigating this variation may help identify factors amenable to systemic improvement interventions. The aims of this study were to identify centre-specific and patient-specific factors associated with variation in HbA1c levels and to determine how these associations contribute to variation in performance across diabetes centres.

Methods

This cross-sectional study analysed data for 5,872 people with type 1 (n = 1,729) or type 2 (n = 4,143) diabetes mellitus collected through the Australian National Diabetes Audit (ANDA). A linear mixed-effects model examined centre-level and patient-level factors associated with variation in HbA1c levels.

Results

Mean age was: 43±17 years (type 1), 64±13 (type 2); median disease duration: 18 years (10,29) (type 1), 12 years (6,20) (type 2); female: 52% (type 1), 45% (type 2). For people with type 1 diabetes, volume of patients was associated with increases in HbA1c (p = 0.019). For people with type 2 diabetes, type of centre was associated with reduction in HbA1c (p <0.001), but location and patient volume were not. Associated patient-level factors associated with increases in HbA1c included past hyperglycaemic emergencies (type 1 and type 2, p<0.001) and Aboriginal and Torres Strait Islander status (type 2, p<0.001). Being a non-smoker was associated with reductions in HbA1c (type 1 and type 2, p<0.001).

Conclusions

Centre-level and patient-level factors were associated with variation in HbA1c, but patient-level factors had greater impact. Interventions targeting patient-level factors conducted at a centre level including sick-day management, smoking cessation programs and culturally appropriate diabetes education for and Aboriginal and Torres Strait Islander peoples may be more important for improving glycaemic control than targeting factors related to the Centre itself.

Cardiovascular disease in patients with type 1 diabetes: Early evaluation, risk factors and possible relation with cardiac autoimmunity

Cardiovascular disease now is the leading cause of mortality among patients with type 1 diabetes (T1D). The risk of death from cardiovascular events in subjects with T1D is 2-10 times higher than the general population, depending on blood glucose control. Although complications of cardiovascular disease occur in middle and old age, pathological processes begin in childhood. Some methods used to evaluate subclinical cardiovascular disease, such as carotid intima-media thickness and pulse wave velocity, can detect early cardiovascular abnormalities in adolescence. The effect of risk factors including hypertension, dyslipidemia and diabetic nephropathy on cardiovascular disease has been well studied. According to the current clinical practice recommendations from the American Diabetes Association, cardiovascular risk factors should be systematically assessed at least annually and treated as recommended. And yet, the effects of intensive insulin therapy on cardiovascular risk, as well as the mechanisms of cardiac autoimmunity require further studying. This review concentrates on the cardiovascular risk in type 1 diabetes in order to provide a comprehensive outlook of its epidemiology, early assessment, risk factors and possible relations with cardiac autoimmunity, aiming to propose promising therapeutic strategies.

Cardiovascular health in emerging adults with type 1 diabetes

AIMS

Individuals with type 1 diabetes (T1D) face increased risk for cardiovascular disease (CVD). Controlling individual cardiovascular risk factors can prevent or slow the onset of CVD. Ideal cardiovascular health is associated with a lower incidence of CVD. Identifying areas of suboptimal cardiovascular health can help guide CVD prevention interventions. To assess cardiovascular health and explore the barriers and facilitators to achieving ideal cardiovascular health in a sample of young adults with T1D.

METHODS AND RESULTS

We used a sequential mixed-method design to assess the seven factors of cardiovascular health according to American Heart Association. Qualitative interviews, guided by Pender's Health Promotion Model, were used to discuss participant's cardiovascular health results and the barriers and facilitators to achieving ideal cardiovascular health. We assessed the frequency of ideal levels of each factor. The qualitative data were analysed using content analysis. Qualitative and quantitative data were integrated in the final analysis phase. The sample (n = 50) was majority female (70%), White (86%), with a mean age of 22 ± 2.4 and diabetes duration of 10.7 ± 5.5 years. Achievement of the seven factors of cardiovascular health were: non-smoking (96%); cholesterol <200 mg/dL (76%); body mass index <25 kg/m2 (54%); blood pressure <120/<80 mmHg (46%); meeting physical activity guidelines (38%); haemoglobin A1c <7% (40%); and healthy diet (14%). Emerging qualitative themes related to the perceived benefits of action, interpersonal influences on their diabetes self-management, and perceived self-efficacy.

CONCLUSION

We found areas of needed improvement for cardiovascular health. However, these young adults expressed a strong interest in healthy habits which can be supported by their healthcare providers.

What Gets Measured Gets Improved-Setting Standards and Accreditation for Quality Improvement for Diabetes Services in Australia

The purpose of this article is to illustrate that setting standards of care is the cornerstone for excellence in diabetes management. This is underpinned by 3 activities: a standards and accreditation process, an audit and benchmarking program and a linked quality improvement plan. While there are many examples of local auditing and quality improvement programs, there are very few that are at a national level. The National Association of Diabetes Centres (NADC) was formed by the Australian Diabetes Society and the Australian Diabetes Educators Association to set standards of diabetes care in Australia. A rigorous accreditation process was put in place to recognize primary, secondary, and tertiary level diabetes centers that meet these standards. The NADC accreditation process is underpinned by a quality improvement plan, which must be submitted for accreditation to be granted and is informed by the Australian National Diabetes Audit (ANDA). ANDA is conducted annually to gather information about treatments, complications, self-care practices and quality of life outcomes and provides a national as well as an individual report to the participating center that is used to benchmark against other like centers. The ANDA reports are important to inform national policy and advocacy for diabetes care and to also provide information for quality improvement purposes for the individual participating center. We believe that the NADC Standards and Accreditation can be an exemplar for other countries to adapt and adopt to standardize diabetes care at the highest level.

Cost-Effectiveness Analysis of a Hybrid Closed-Loop System Versus Multiple Daily Injections and Capillary Glucose Testing for Adults with Type 1 Diabetes

Background: Hybrid closed-loop systems may offer improved HbA1c levels, more time-in-range, and less hypoglycemia than alternative treatment strategies. However, it is unclear if glycemic improvements offset this technology's higher acquisition costs. Among adults with type 1 diabetes in Australia, we sought to evaluate the cost-effectiveness of a hybrid closed-loop system in comparison with the current standard of care, comprising insulin injections and capillary glucose testing. Methods: Cost-effectiveness analysis was performed using decision analysis in combination with a Markov model to simulate disease progression in a cohort of adults with type 1 diabetes and compare the downstream health and economic consequences of hybrid closed-loop therapy versus current standard of care. Transition probabilities and utilities were sourced from published studies. Costs were considered from the perspective of the Australian health care system. A lifetime horizon was considered, with annual discount rates of 5% applied to future costs and outcomes. Uncertainty was assessed with probabilistic and deterministic sensitivity analyses. Results: Use of a hybrid closed-loop system resulted in an incremental cost-effectiveness ratio of Australian dollars (AUD) 37,767 per quality-adjusted life year (QALY) gained. This is below the traditionally cited willingness to pay a threshold of $50,000 per QALY gained in the Australian setting. Sensitivity analyses that varied baseline glycemic control, treatment effects, technology costs, age, discount rates, and time horizon indicated the results to be robust. Conclusions: For adults with type 1 diabetes, hybrid closed-loop therapy is likely to be cost-effective compared with multiple daily injections and capillary glucose testing in Australia.

Evaluation of cardiovascular risk in adults with type 1 diabetes: poor concordance between the 2019 ESC risk classification and 10-year cardiovascular risk prediction according to the Steno Type 1 Risk Engine

BACKGROUND

Patients with type 1 diabetes (T1D) have higher mortality risk compared to the general population; this is largely due to increased rates of cardiovascular disease (CVD). As accurate CVD risk stratification is essential for an appropriate preventive strategy, we aimed to evaluate the concordance between 2019 European Society of Cardiology (ESC) CVD risk classification and the 10-year CVD risk prediction according to the Steno Type 1 Risk Engine (ST1RE) in adults with T1D.

METHODS

A cohort of 575 adults with T1D (272F/303M, mean age 36 ± 12 years) were studied. Patients were stratified in different CVD risk categories according to ESC criteria and the 10-year CVD risk prediction was estimated with ST1RE within each category.

RESULTS

Men had higher BMI, WC, SBP than women, while no difference was found in HbA1c levels between genders. According to the ESC classification, 92.5% of patients aged < 35 years and 100% of patients ≥ 35 years were at very high/high risk. Conversely, using ST1RE to predict the 10-year CVD risk within each ESC category, among patients at very high risk according to ESC, almost all (99%) had a moderate CVD risk according to ST1RE if age < 35 years; among patients aged ≥35 years, the majority (59.1%) was at moderate risk and only 12% had a predicted very high risk by ST1RE. The presence of target organ damage or three o more CV risk factors, or early onset T1D of long duration (> 20 years) alone identified few patients (< 30%) among those aged ≥35 years, who were at very high risk according to ESC, in whom this condition was confirmed by ST1RE; conversely, the coexistence of two or more of these criteria identified about half of the patients at high/very high risk also according to this predicting algorithm. When only patients aged ≥ 50 years were considered, there was greater concordance between ESC classification and ST1RE prediction, since as many as 78% of those at high/very high risk according to ESC were confirmed as such also by ST1RE.

CONCLUSIONS

Using ESC criteria, a large proportion (45%) of T1D patients without CVD are classified at very high CVD risk; however, among them, none of those < 35 years and only 12% of those ≥ 35 years could be confirmed at very high CVD risk by the ST1RE predicting algorithm. More studies are needed to characterize the clinical and metabolic features of T1D patients that identify those at very high CVD risk, in whom a very aggressive cardioprotective treatment would be justified.

Dyslipidemia in Type 1 Diabetes: AMaskedDanger

Type 1 diabetes (T1D) patients show lipid disorders which are likely to play a role in their increased cardiovascular (CV) disease risk. Quantitative abnormalities of lipoproteins are noted in T1D with poor glycemic control. In T1D with optimal glycemic control, triglycerides and LDL-cholesterol are normal or slightly decreased whereas HDL-cholesterol is normal or slightly increased. T1D patients, even with good glycemic control, show several qualitative and functional abnormalities of lipoproteins that are potentially atherogenic. An association between these abnormalities and CV disease risk has been reported in recent studies. Although the mechanisms underlying T1D dyslipidemia remain unclear, the subcutaneous route of insulin administration, that is responsible for peripheral hyperinsulinemia, is likely to be an important factor.

The relationship between carotid disease and retinopathy in diabetes: a systematic review

BACKGROUND

Since studies of the relationship between carotid disease and diabetic retinopathy (DR) have shown apparent inconsistencies, the aim of this study was to conduct a systematic review of available published data.

METHODS

Electronic databases were searched independently by two reviewers, according to an iterative protocol, for relevant articles. The search term used was "diabetes AND (carotid disease OR intima-media OR carotid plaque OR carotid stenosis OR carotid arterial disease OR carotid artery disease OR carotid atherosclerosis) AND (retinopathy OR diabetic retinopathy)".

RESULTS

From 477 publications, 14 studies were included. There were differences in the variables used as markers of carotid disease and DR across the included studies. Ten studies used carotid disease as the dependent variable, and the remainder used DR. All but one study involved cross-sectional data. Most studies reported a statistically significant association between at least one parameter of carotid disease as assessed by ultrasound and DR presence or severity. Only four studies reported no significant association. A common limitation was the use of convenience participant sampling.

CONCLUSIONS

There appears to be an increased likelihood of DR when there is ultrasonographic evidence of carotid disease, and vice versa. The available studies suggest that there may be a direct relationship between DR and carotid macrovascular disease and/or that these complications co-exist due to shared risk factors. If carotid disease is detected, retinal assessment should be performed. If DR is identified, intensive cardiovascular disease risk management should be considered. Additional longitudinal studies are needed to assess the directionality of the association.

Microvascular complications burden (nephropathy, retinopathy and peripheral polyneuropathy) affects risk of major vascular events and all-cause mortality in type 1 diabetes: a 10-year follow-up study

BACKGROUND

Microvascular complications (MC) have been claimed to increase the risk for cardiovascular disease in diabetic subjects. However, the effect of MC burden on the risk of major vascular outcomes and all-cause mortality in type 1 diabetes is still poorly explored. We evaluated the relationship between microvascular complications burden and incidence of major cardiovascular events and all-cause mortality in subjects with type 1 diabetes.

METHODS

We recruited 774 participants with type 1 diabetes in a single-center observational study over a follow-up of 10.8 ± 2.5 years. Hazard ratios (HR) for cardiovascular outcomes and all-cause death associated with microvascular complications were determined by unadjusted and adjusted Cox regression analysis.

RESULTS

Out of 774 individuals, 54.9% had no-MC, 32.3% 1 MC, 9.7% 2 MC and 3.1% 3 MC. A total of 54 deaths (7.0%) occurred. Death rate increased from no-MC 2.1% (Ref) to 1 MC 7.2% (HR 3.54 [95% CI 1.59-7.87]), 2 MC 14.7% (HR 6.41 [95% CI 2.65-15.49]) and 3 MC 66.7% (HR 41.73 [95% CI 18.42-94.57], p < 0.0001). After adjustments, HRs were: 1 MC 2.05 (95% CI 0.88-4.76), 2 MC 1.98 (95% CI 0.75-5.21), 3 MC 7.02 (95% CI 2.44-20.20, p = 0.002). Forty-nine subjects (6.7%) had at least one cardiovascular event, and cumulative incidence went from no-MC 2.2% (Ref) to 1 MC 5.0%; (HR 2.27 [95% CI 0.96-5.38]), 2 MC 26.8% (HR 12.88 [95% CI 5.82-28.50]) and 3 MC 40.9% (HR 29.34 [95% CI 11.59-74.25], p < 0.0001). Upon adjustments, HRs were: 1 MC 1.59 (95% CI 0.65-3.88), 2 MC 4.33 (95% CI 1.75-10.74), 3 MC 9.31 (95% CI 3.18-27.25, p < 0.0001). Thirty-five individuals (4.8%) had at least one coronary event, which cumulative incidence increased with MC burden (p < 0.0001).

CONCLUSIONS

In type 1 diabetes, microvascular complications burden increases in an independent dose-dependent manner the risk of major cardiovascular outcomes and all-cause mortality. The presence and number of microvascular complications should be considered in stratifying overall cardiovascular risk in type 1 diabetes.

Risk of early mortality and cardiovascular disease in type 1 diabetes: a comparison with type 2 diabetes, a nationwide study

Background

Both type 1 and type 2 diabetes are well-established risk factors for cardiovascular disease and early mortality. However, few studies have directly compared the hazards of cardiovascular outcomes and premature death among people with type 1 diabetes to those among people with type 2 diabetes and subjects without diabetes. Furthermore, information about the hazard of cardiovascular disease and early mortality among Asians with type 1 diabetes is sparse, although the clinical and epidemiological characteristics of Asians with type 1 diabetes are unlike those of Europeans. We estimated the hazard of myocardial infarction (MI), hospitalization for heart failure (HF), atrial fibrillation (AF), and mortality during follow-up in Korean adults with type 1 diabetes compared with those without diabetes and those with type 2 diabetes.

Methods

We used Korean National Health Insurance Service datasets of preventive health check-ups from 2009 to 2016 in this retrospective longitudinal study. The hazard ratios of MI, HF, AF, and mortality during follow-up were analyzed using the Cox regression analyses according to the presence and type of diabetes in ≥ 20-year-old individuals without baseline cardiovascular disease (N = 20,423,051). The presence and type of diabetes was determined based on the presence of type 1 or type 2 diabetes at baseline.

Results

During more than 93,300,000 person-years of follow-up, there were 116,649 MIs, 135,532 AF cases, 125,997 hospitalizations for HF, and 344,516 deaths. The fully-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident MI, hospitalized HF, AF, and all-cause death within the mean follow-up of 4.6 years were higher in the type 1 diabetes group than the type 2 diabetes [HR (95% CI) 1.679 (1.490–1.893) for MI; 2.105 (1.901–2.330) for HF; 1.608 (1.411–1.833) for AF; 1.884 (1.762–2.013) for death] and non-diabetes groups [HR (95% CI) 2.411 (2.138–2.718) for MI; 3.024 (2.730–3.350) for HF; 1.748 (1.534–1.993) for AF; 2.874 (2.689–3.073) for death].

Conclusions

In Korea, the presence of diabetes was associated with a higher hazard of cardiovascular disease and all-cause death. Specifically, people with type 1 diabetes had a higher hazard of cardiovascular disease and all-cause mortality compared to people with type 2 diabetes.

Serum apolipoproteins and apolipoprotein-defined lipoprotein subclasses: a hypothesis-generating prospective study of cardiovascular events in T1D

APOB, APOC3, and APOE and apolipoprotein-defined lipoprotein subclasses (ADLSs; based on qualitative apolipoprotein complement) have been associated with dyslipidemia and CVD. Our main objective was to define associations of serum apolipoproteins and ADLSs with "any CVD" and "major atherosclerotic cardiovascular events" (MACEs) in a prospective study of T1D. Serum apolipoproteins and ADLSs (14 biomarkers in total) were measured in sera (obtained between 1997 and 2000) from a subset (n = 465) of the Epidemiology of Diabetes Interventions and Complications cohort. Prospective associations of "any CVD" (myocardial infarction, stroke, confirmed angina, silent myocardial infarction, revascularization, or congestive heart failure) and MACEs (fatal or nonfatal myocardial infarction or stroke), over 5,943 and 6,180 patient-years follow-up, respectively, were investigated using Cox proportional hazards models that were unadjusted and adjusted for risk factors. During 15 years of follow-up, 50 "any CVD" events and 24 MACEs occurred. Nominally significant positive univariate associations with "any CVD" were APOB, APOC3 and its subfractions [heparin precipitate, heparin-soluble (HS)], and ADLS-defined Lp-B. In adjusted analyses, APOC3-HS remained nominally significant. Nominally significant positive univariate associations with MACEs were APOC3 and its subfractions and Lp-B:C; those with total APOC3 and APOC3-HS persisted in adjusted analyses. However, these associations did not reach significance after adjusting for multiple testing. There were no significant associations of APOA1, APOA2, APOE, or other ADLSs with either "any CVD" or MACEs. These hypothesis-generating data suggest that total serum APOC3 and APOC3 in HDL are potentially important predictive biomarkers for any CVD and MACEs in adults with T1D.

Lower HDL-cholesterol, a known marker of cardiovascular risk, was associated with depression in type 1 diabetes: a cross sectional study

BACKGROUND

Depression, metabolic disturbances and inflammation have been linked to cardiovascular disease and mortality. Low levels of high-density lipoprotein cholesterol (HDL-cholesterol), a known marker of cardiovascular risk, have been observed in patients with major depression in psychiatric populations. Our main aim was to explore associations between depression, antidepressants, and metabolic and inflammatory variables in patients with type 1 diabetes (T1D). A secondary aim was to explore variables associated with HDL-cholesterol.

METHODS

Cross-sectional design. T1D patients (n = 292, men 55%, age18-59 years, diabetes duration ≥1 year) were consecutively recruited from one specialist diabetes clinic. Depression was defined as ≥8 points for Hospital Anxiety and Depression Scale-Depression sub scale. Blood samples, anthropometrics, blood pressure, and data regarding medication and life style were collected from electronic health records. Non-parametric tests, multiple logistic and linear regression analyses were performed.

RESULTS

The depression prevalence was 10 and 8% used antidepressants. Median (q1, q3) HDL-cholesterol (mmol/l) was for the depressed 1.3 (1.2, 1.5) and for the non-depressed 1.6 (1.3, 1.8), p = 0.001. HDL-cholesterol levels (per mmol/l) were negatively associated with depression (Adjusted odds ratio (AOR) 0.2, p = 0.007), and the use of antidepressants was positively associated with depression (AOR 8.1, p <  0.001). No other metabolic or inflammatory variables, or life style factors, were associated with depression when adjusted for antidepressants. Abdominal obesity was associated with antidepressants in women (AOR 4.6, p = 0.029). Decreasing HDL-cholesterol levels were associated with increasing triglyceride levels (p <  0.001), increasing high-sensitive C-reactive protein (hs-CRP) levels (p = 0.021), younger age (p <  0.001), male sex (p <  0.001), and depression (p = 0.045).

CONCLUSIONS

Lower HDL-cholesterol levels, known predictors of cardiovascular disease, were associated with depression in patients with T1D. The use of antidepressants was associated with abdominal obesity in women. Depression, low-grade inflammation measured as hs-CRP, higher triglycerides, male sex, and lower age were independently associated with lower HDL-cholesterol levels.