Continuous relationships between non-diabetic hyperglycaemia and both cardiovascular disease and all-cause mortality: the Australian Diabetes, Obesity, and Lifestyle (AusDiab) study

Associations of fasting plasma glucose with all-cause mortality and cardiovascular events in older Chinese diabetes patients: A population-based cohort study

AIMS/INTRODUCTION

Our aim was to investigate the optimal fasting glucose (FPG) range in Chinese older adults with type 2 diabetes, and to clarify whether the optimal range varies according to the control of risk factors.

MATERIALS AND METHODS

The baseline survey for the cohort study began in 2018, with follow up ending in 2022. Our study enrolled 59,030 older diabetes patients with no history of cardiovascular disease (CVD). Participants were divided into nine groups based on their baseline glycemic status. The association between FPG and the risk of adverse outcomes was mainly estimated by multivariate Cox proportional risk models and restricted spline analysis.

RESULTS

During the 4-year follow-up period, a total of 5,637 deaths and 4,904 CVD events occurred. The associations of FPG with mortality and CVD events showed J-shaped curves. Among all-cause deaths, the hazard ratios for FPG ≤4.50 and >11.50 mmol/L were 1.50 (95% confidence interval [CI] 1.31-1.71) and 1.84 (95% CI 1.67-2.02). Among CVD, the hazard ratios for FPG ≤4.50 and >11.50 mmol/L were 1.31 (95% CI 1.13-1.53) and 1.71 (95% CI 1.54-1.89), respectively. The optimal FPG ranges of all-cause mortality and CVD were 5.50-7.50 and 4.50-7.50 mmol/L, respectively. For participants with at least two risk factors, the optimal FPG levels were higher than those with fewer risk factors.

CONCLUSIONS

In older Chinese diabetes patients, the FPG ranges related to the minimum death and CVD event rates were 5.50-7.50 and 4.50-7.50 mmol/L, respectively. Patients with more cardiovascular risk factors had higher optimal blood glucose ranges than those with fewer risk factors.

HbA1c and fasting plasma glucose levels are equally related to incident cardiovascular risk in a high CVD risk population without known diabetes

OBJECTIVES

Type 2 diabetes (T2DM) is associated with increased risk for cardiovascular disease (CVD). Whether screen-detected T2DM, based on fasting plasma glucose (FPG) or on HbA1c, are associated with different risks of incident CVD in high-risk populations and which one is preferable for diabetes screening in these populations, remains unclear.

METHODS

8,274 high-risk CVD participants were included from the UCC-SMART cohort. Participants were divided into groups based on prior T2DM diagnosis, and combinations of elevated/non-elevated FPG and HbA1c (cut-offs at 7 mmol/L and 48 mmol/mol, respectively): Group 0: known T2DM; group 1: elevated FPG/HbA1c; group 2: elevated FPG, non-elevated HbA1c; group 3: non-elevated FPG, elevated HbA1c; group 1 + 2: elevated FPG, regardless of HbA1c; group 1 + 3: elevated HbA1c, regardless of FPG; and group 4 (reference), non-elevated FPG/HbA1c.

RESULTS

During a median follow-up of 6.3 years (IQR 3.3-9.8), 712 cardiovascular events occurred. Compared to the reference (group 4), group 0 was at increased risk (HR 1.40; 95 % CI 1.16-1.68), but group 1 (HR 1.16; 95 % CI 0.62-2.18), 2 (HR 1.18; 95 % CI 0.84-1.67), 3 (HR 0.61; 95 % CI 0.15-2.44), 1 + 2 (HR 1.17; 95 % CI 0.86-1.59) and 1 + 3 (HR 1.01; 95 % CI 0.57-1.79) were not. However, spline interpolation showed a linearly increasing risk with increasing HbA1c/FPG, but did not allow for identification of other cut-off points.

CONCLUSIONS

Based on current cut-offs, FPG and HbA1c at screening were equally related to incident CVD in high-risk populations without known T2DM. Hence, neither FPG, nor HbA1c, is preferential for diabetes screening in this population with respect to risk of incident CVD.

The associations of risk of cardiovascular disease with development stages of diabetes in Chinese population: findings from a retrospective cohort study in QuZhou city

BACKGROUND

Risk analysis is an important area of research in diabetes and cardiovascular disease (CVD), both of which have significant global health burdens. Although there is evidence that patients with prediabetes and diabetes mellitus may have an increased risk of CVD, few studies have been conducted in mainland China.

METHODS

This retrospective cohort study utilized data from the Quzhou City Resident Health Information System and the Zhejiang Province Chronic Disease Surveillance System in China. Prediabetes and diabetes mellitus were the exposure interests, and the outcome event was defined as the onset of cardiovascular and cerebrovascular disease (including coronary heart disease and stroke). The start date of the study was January 1, 2015, and the follow-up deadline was December 31, 2020. Multivariate Cox proportional hazard model were used to assess the associations among prediabetes, diabetes, and CVD risk. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. Our study used follow-up time as the time scale, while adjusting for age, sex, physical activity, smoking, alcohol consumption, BMI in the models Sensitivity analyses were conducted to assess the stability of the results, by excluding participants who smoked and drank alcohol, participants who developed CVD in the first year of follow-up.

RESULTS

In total, 138,970 participants were included in our study, with a mean follow-up of 5.8 years. The mean age of the participants was 58.82 ± 14.44 years, with 42.79% (n = 59,466) males and 57.21% (n = 79,504) females. During the study period 4357 cases of CVD were recorded. Participants with prediabetes (P = 0.003) and diabetes (P < 0.001) had a higher risk of CVD than those who were Normal (HR [95% CI]: 1.14 [1.05-1.24]; 1.68 [1.55-1.81], respectively). Prediabetes and patients living with diabetes had a 14% and 68% increased risk of CVD, respectively. The results of the sensitivity analyses were consistent with those of the main analyses after excluding those who developed CVD within one year of follow-up and those who were concurrent smokers or alcohol drinkers.

CONCLUSIONS

Our research found that prediabetes is significantly associated with the risk of diabetes and CVD.

Trends in cardiovascular risk factors control among US adults by glycemic statuses, 2007-2018

AIMS

Understanding the national trends in cardiovascular risk factors control of individuals with prediabetes and diabetes is critical for diabetes prevention and management. Our study aims to estimate how cardiovascular risk factors changed in US adults with different glycemic statuses between 2007-2008 and 2017-2018.

METHODS AND RESULTS

This was a serial cross-sectional study based on the National Health and Nutrition Examination Surveys (between 2007-2008 and 2017-2018 cycle). Non-pregnant American participants aged 20 years or older were included. Cardiovascular risk factors including weight, blood pressure, plasma cholesterol, and smoking by glycemic statuses were estimated. A total of 33 040 American adults were included. From 2007-2008 to 2017-2018, the age-adjusted proportions of individuals who reached weight control (body mass index <30 kg/m2) of both normoglycemia group and prediabetes group had a significant decrease over the study period, while the trend in participants with diabetes was not significant (mean difference: -5.34%, 95% confidence interval: -15.28%, 4.59%; P for trend = 0.298). The age-adjusted means of total cholesterol of all three groups decreased during the study decade (P for trend < 0.010), with participants with diabetes maintaining the lowest level. Individuals with high total cholesterol were more likely to receive statin therapy in the diabetes group. Notably, prediabetes participants had the highest level of total cholesterol and low-density lipoprotein cholesterol and were less likely to achieve lipid control with statin therapy. Sensitivity analysis with the second definition of prediabetes and diabetes resulted in a consistent trend.

CONCLUSIONS

In this nationally representative cross-sectional study, we systematically estimated the cardiovascular risk factors control in American adults and found poor weight control in the normoglycemia and prediabetes group. Despite the significant decrease trend of plasma total cholesterol in all groups, the high cholesterol level in the prediabetes group deserves special concern.

Progression from different blood glucose states to cardiovascular diseases: a prospective study based on multi-state model

AIMS

To quantify the trajectories from normoglycaemia to pre-diabetes, subsequently to type 2 diabetes mellitus (T2DM), cardiovascular diseases (CVD), and cardiovascular death, and the effects of risk factors on the rates of transition.

METHODS AND RESULTS

We used data from the Jinchang Cohort of 42 585 adults aged 20-88 free of coronary heart disease (CHD) and stroke at baseline. A multistate model was applied for analysing the progression of CVD and its relation to various risk factors. During a median follow-up of 7 years, 7498 participants developed pre-diabetes, 2307 developed T2DM, 2499 developed CVD, and 324 died from CVD. Among 15 postulated transitions, transition from comorbid CHD and stroke to cardiovascular death had the highest rate (157.21/1000 person-years), followed by transition from stroke alone to cardiovascular death (69.31/1000 person-years) and transition from pre-diabetes to normoglycaemia (46.51/1000 person-years). Pre-diabetes had a sojourn time of 6.77 years, and controlling weight, blood lipids, blood pressure, and uric acid within normal limits may promote reversion to normoglycaemia. Among transitions to CHD alone and stroke alone, transition from T2DM had the highest rate (12.21/1000 and 12.16/1000 person-years), followed by transition from pre-diabetes (6.81/1000 and 4.93/1000 person-years) and normoglycaemia (3.28/1000 and 2.39/1000 person-years). Age and hypertension were associated with an accelerated rate for most transitions. Overweight/obesity, smoking, dyslipidaemia, and hyperuricaemia played crucial but different roles in transitions.

CONCLUSION

Pre-diabetes was the optimal intervention stage in the disease trajectory. The derived transition rates, sojourn time, and influence factors could provide scientific support for the primary prevention of both T2DM and CVD.

Enhancing cardiometabolic health through physical activity and breakfast manipulations in children and adolescents: good for humans, good for the planet

The human health benefits of cardiometabolic disease prevention can be accompanied by planetary co-benefits. Focusing efforts towards young people, including children and adolescents, is conducive to disease prevention. In the context of cardiometabolic disease prevention, this review paper critically summarises the available literature on the acute cardiometabolic responses to physical activity and breakfast manipulations among young people. Given the seriousness of global climate change, which will disproportionally affect our younger generations, this review paper offers new insights into the inherent interactions between child-adolescent behaviour and cardiometabolic health from an environmental sustainability perspective to aid climate change mitigation efforts, including exploring future research avenues. A growing evidence base suggests acute moderate- to high-intensity exercise bouts can attenuate postprandial plasma glucose, insulin and triacylglycerol concentrations for up to 24-48 h in young people. Whether accumulating physical activity throughout the day with short, frequent bouts promotes cardiometabolic risk marker attenuations is unclear. Breakfast consumption may enhance free-living physical activity and reduce glycaemic responses to subsequent meals for a possible additive impact. If repeated habitually, attenuations in these cardiometabolic risk factors would be conducive to disease prevention, reducing the greenhouse gas emissions associated with disease diagnosis and treatment. To progress current understanding with high public health and planetary relevance, research among samples of 'at risk' young people that span cellular-level responses to ecologically valid settings and address human and planetary health co-benefits is needed. Indeed, certain physical activity opportunities, such as active travel to school, offer important direct co-benefits to humans and planetary health.

A randomized clinical trial comparing low-fat with precision nutrition-based diets for weight loss: impact on glycemic variability and HbA1c

BACKGROUND

Recent studies have demonstrated considerable interindividual variability in postprandial glucose response (PPGR) to the same foods, suggesting the need for more precise methods for predicting and controlling PPGR. In the Personal Nutrition Project, the investigators tested a precision nutrition algorithm for predicting an individual's PPGR.

OBJECTIVE

This study aimed to compare changes in glycemic variability (GV) and HbA1c in 2 calorie-restricted weight loss diets in adults with prediabetes or moderately controlled type 2 diabetes (T2D), which were tertiary outcomes of the Personal Diet Study.

METHODS

The Personal Diet Study was a randomized clinical trial to compare a 1-size-fits-all low-fat diet (hereafter, standardized) with a personalized diet (hereafter, personalized). Both groups received behavioral weight loss counseling and were instructed to self-monitor diets using a smartphone application. The personalized arm received personalized feedback through the application to reduce their PPGR. Continuous glucose monitoring (CGM) data were collected at baseline, 3 mo and 6 mo. Changes in mean amplitude of glycemic excursions (MAGEs) and HbA1c at 6 mo were assessed. We performed an intention-to-treat analysis using linear mixed regressions.

RESULTS

We included 156 participants [66.5% women, 55.7% White, 24.1% Black, mean age 59.1 y (standard deviation (SD) = 10.7 y)] in these analyses (standardized = 75, personalized = 81). MAGE decreased by 0.83 mg/dL per month for standardized (95% CI: 0.21, 1.46 mg/dL; P = 0.009) and 0.79 mg/dL per month for personalized (95% CI: 0.19, 1.39 mg/dL; P = 0.010) diet, with no between-group differences (P = 0.92). Trends were similar for HbA1c values.

CONCLUSIONS

Personalized diet did not result in an increased reduction in GV or HbA1c in patients with prediabetes and moderately controlled T2D, compared with a standardized diet. Additional subgroup analyses may help to identify patients who are more likely to benefit from this personalized intervention. This trial was registered at clinicaltrials.gov as NCT03336411.

Association of cardiovascular health score trajectory and risk of subsequent cardiovascular disease in non-diabetic population: a cohort study

BACKGROUND

Diabetes is an important risk factor for cardiovascular disease (CVD), but in the non-diabetic population, high glucose values within the normal range are also positively associated with CVD risk. There is a lack of concern for people without diabetes and evidence is lacking regarding the association between changes in cardiovascular health score (CVHS) and CVD risk in the non-diabetic population.

METHODS

The current study included 37,970 non-diabetic participants free of CVD events in or before 2010 from the Kailuan Study and calculated CVHS according to the overall status of 7 cardiovascular health metrics between the 2006 and 2010 waves. Latent mixture models were used to explore the subgroups with different development trends included in the context of the Kailuan non-diabetic population and to identify the trajectory of each subgroup. The outcomes of the current study were CVD events, including myocardial infarction and stroke. CVHS trajectory was developed to predict subsequent CVD risk from 2010 to 2020. The Cox proportional hazard model was established to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) of CVD across different trajectory patterns.

RESULTS

Five distinct CVHS trajectory patterns were identified, including low-stable pattern (n = 2835), moderate-increasing pattern (n = 3492), moderate-decreasing pattern (n = 7526), high-stable I pattern (n = 17,135), and high-stable II pattern (n = 6982). Compared with the low-stable pattern, participants with the high-stable II pattern had a lower subsequent risk of CVD (HR = 0.22, 95%CI = 0.18-0.28); In stratification analysis, the lower risk for CVD was observed in females (HR = 0.10, 95%CI = 0.05-0.23, P for interaction < 0.05) and those aged < 60 years (HR = 0.16, 95%CI = 0.11 to 0.22, P for interaction < 0.05).

CONCLUSIONS

CVHS trajectory patterns were associated with an altered CVD risk in the non-diabetic population. When stratified by age and sex, the association was stronger in young adults and females.

Diagnosis and Management of Prediabetes: A Review

Importance

Prediabetes, an intermediate stage between normal glucose regulation and diabetes, affects 1 in 3 adults in the US and approximately 720 million individuals worldwide.

Observations

Prediabetes is defined by a fasting glucose level of 100 to 125 mg/dL, a glucose level of 140 to 199 mg/dL measured 2 hours after a 75-g oral glucose load, or glycated hemoglobin level (HbA1C) of 5.7% to 6.4% or 6.0% to 6.4%. In the US, approximately 10% of people with prediabetes progress to having diabetes each year. A meta-analysis found that prediabetes at baseline was associated with increased mortality and increased cardiovascular event rates (excess absolute risk, 7.36 per 10 000 person-years for mortality and 8.75 per 10 000 person-years for cardiovascular disease during 6.6 years). Intensive lifestyle modification, consisting of calorie restriction, increased physical activity (≥150 min/wk), self-monitoring, and motivational support, decreased the incidence of diabetes by 6.2 cases per 100 person-years during a 3-year period. Metformin decreased the risk of diabetes among individuals with prediabetes by 3.2 cases per 100 person-years during 3 years. Metformin is most effective for women with prior gestational diabetes and for individuals younger than 60 years with body mass index of 35 or greater, fasting plasma glucose level of 110 mg/dL or higher, or HbA1c level of 6.0% or higher.

Conclusions and Relevance

Prediabetes is associated with increased risk of diabetes, cardiovascular events, and mortality. First-line therapy for prediabetes is lifestyle modification that includes weight loss and exercise or metformin. Lifestyle modification is associated with a larger benefit than metformin.

Association between breakfast frequency and insulin resistance in Korean adults with prediabetes: A nationwide population-based cross-sectional study

AIMS

This study aimed to investigate the association between breakfast frequency and insulin resistance using the triglyceride and glucose (TyG) index in Korean adults with prediabetes.

METHODS

This study used data from the 2016-2018 Korea National Health and Nutrition Examination Survey (KNHANES). A total of 16,925 participants were included in this study. Breakfast frequency was classified as 0 times, 1-4 times, and 5-7 times per week. High insulin resistance was defined as a TyG index of ≥8.5. A multivariate logistic regression analysis was performed.

RESULTS

Compared with the group whose breakfast frequency was 5-7 times per week, the odds ratio for high insulin resistance was 1.39 times (95% confidence interval (CI), 1.21-1.59) and 1.17 times (95% CI, 1.04-1.32) higher in the group whose breakfast frequency was 0 times and 1-4 times per week, respectively.

CONCLUSIONS

This study revealed that a lower frequency of breakfast consumption was significantly associated with a higher risk of insulin resistance in Korean adults with prediabetes. In the future, a large-scale prospective longitudinal study is required to establish the causal relationship between breakfast frequency and insulin resistance.

Diabetes incidence in subjects with PREDIABetes from ReUNion Island: the PREDIABRUN observational cohort study protocol

INTRODUCTION

Improved knowledge of prediabetic subjects' profile and their risk of developing type 2 diabetes mellitus (T2DM) would enhance secondary prevention. The primary objective is to describe factors associated with incident T2DM in subjects with pre-diabetes diagnosed in primary care.

METHODS AND ANALYSIS

The study is based on Reunion Island, a French overseas region that experiences a particularly high disease burden of T2DM. This is an observational, non-randomised prospective cohort study conducted in primary care in which private general practitioner (GP) investigators recruit participants with pre-diabetes from their practices regardless of the initial motive for consultation. Pre-diabetes is defined by WHO criteria, that is, fasting plasma glucose between 1.10 g/L and 1.25 g/L and/or plasma glucose 2 hours after ingestion of 75 g of glucose (2-hour post load plasma glucose) between 1.40 g/L and 1.99 g/L. The design is based on an annual follow-up by the GP (according to French National Health Authority recommendations) with collection of clinical and laboratory data and specific lifestyle questionnaires answered by telephone at three time points: inclusion, and at 2-year and 5-year follow-up visits. Follow-up clinical and laboratory data are collected by the investigating GP as part of the study, and study-specific laboratory collections (serum, DNA and urine) will be obtained 2 and 5 years after inclusion. The primary outcome is transition to T2DM.

ETHICS AND DISSEMINATION

This protocol has been approved by the research ethics committee of Saint Etienne (CPP Saint Etienne reference number: 2019-03). Enrolment began in August 2019. Results will be disseminated in at least three papers published in peer-reviewed medical journals, one oral communication and a large-scale communication to the local population and healthcare policymakers.

TRIAL REGISTRATION NUMBER

NCT04463160 and ID-RCB 2018-A03106-49.

Vascular complications in prediabetes and type 2 diabetes: a continuous process arising from a common pathology

The term, "prediabetes", describes a state of hyperglycaemia that is intermediate between true normoglycaemia and the diagnostic cut-offs for indices of glycaemia that are used to diagnose type 2 diabetes. The presence of prediabetes markedly increases the risk of developing type 2 diabetes. Numerous randomized, controlled evaluations of various agents have demonstrated significant prevention or delay of the onset of type 2 diabetes in subjects with prediabetes. Intensive lifestyle interventions and metformin have been studied most widely, with the lifestyle intervention being more effective in the majority of subjects. The application of therapeutic interventions at the time of prediabetes to preserve long-term outcomes has been controversial, however, due to a lack of evidence relating to the pathogenic effects of prediabetes and the effectiveness of interventions to produce a long-term clinical benefit. Recent studies have confirmed that prediabetes, however defined, is associated with a significantly increased risk of macrovascular and microvascular complications essentially identical to those of diabetes, and also with subclinical derangements of the function of microvasculature and neurons that likely signify increased risk of compilations in future. Normoglycaemia, prediabetes and type 2 diabetes appear to be part of a continuum of increased risk of adverse outcomes. Long-term (25-30 years) post-trial follow up of two major diabetes prevention trials have shown that short-term interventions to prevent diabetes lead to long-term reductions in the risk of complications. These findings support the concept of therapeutic intervention to preserve long-term health in people with prediabetes before type 2 diabetes becomes established.

1-h post-load plasma glucose for detecting early stages of prediabetes

Prediabetes is a very prevalent condition associated with an increased risk of developing diabetes and/or other chronic complications, in particular cardiovascular disorders. Early detection is therefore mandatory since therapeutic interventions may limit the development of these complications. Diagnosis of prediabetes is currently based on glycemic criteria (fasting plasma glucose (PG), and/or glycemia at 120 min during a 75 g oral glucose tolerance test (OGTT) and/or glycated hemoglobin (HbA1c). Accumulating longitudinal evidence suggests that a 1-hour PG ≥155 mg/dl (8.6 mmol/l) during the OGTT is an earlier marker of prediabetes than fasting PG, 2-h post-load PG, or HbA1c. There is substantial evidence demonstrating that the 1-h post-load PG is a more sensitive predictor of type 2 diabetes, cardiovascular disease, microangiopathy and mortality compared with conventional glucose criteria. The aim of this review is to highlight the paramount importance of detecting prediabetes early in its pathophysiological course. Accordingly, as recommended by an international panel in a recent petition, 1-h post-load PG could replace current criteria for diagnosing early stages of "prediabetes" before prediabetes evolves as conventionally defined.

Association between haemoglobin A1c and all-cause and cause-specific mortality in middle-aged and older Koreans: a prospective cohort study

Background

This study aimed to examine associations between haemoglobin A1c (HbA1c) levels over time and all-cause and cause-specific mortality in middle-aged and older Koreans.

Methods

Using 16 years of follow-up data from the Korean Genome and Epidemiology Study, we analysed 9294 individuals aged 40–69 years with no history of cardiovascular disease (CVD) or cancer. Participants were divided into a known diabetes group and five groups categorized by HbA1c levels (< 5.0%, 5.0–5.4%, 5.5–5.9%, 6.0–6.4%, and ≥ 6.5%). Hazard ratios (HRs) for all-cause and cause-specific mortality associated with HbA1c levels were calculated using a conventional and a time-dependent Cox proportional hazards model. Restricted cubic spline models were fitted to investigate the relationship between continuous HbA1c levels and mortality among people without known diabetes. Subgroup analyses were performed for age, sex, smoking, hypertension, liver diseases, and red blood cell counts.

Results

During a median follow-up period of 15.7 years, there were 944 deaths, including 185 deaths from CVD, 359 from cancer, and 125 from all external causes. Compared with participants with HbA1c levels of 5.5–5.9%, multivariate-adjusted HRs and 95% confidence intervals for all-cause death of participants with levels < 5.0%, 5.0–5.4%, 6.0–6.4%, and ≥ 6.5% and participants with known diabetes were 1.84 (1.35–2.51), 1.13 (0.95–1.34), 1.30 (1.04–1.62), 1.37 (0.97–1.93), and 2.03 (1.70–2.44), respectively. The risk of cancer mortality was significantly increased in HbA1c < 5.0% (HR, 2.21; 95% CI 1.42–3.44) and known diabetes (HR, 1.60; 95% CI 1.18–2.15). When we performed diverse subgroup analyses, low HbA1c levels at baseline were strongly associated with mortality in participants with liver diseases.

Conclusions

We found U-shaped associations between HbA1c levels at baseline and over time and all-cause mortality in middle-aged and older Koreans. Additionally, the risk of cancer mortality increased both in low and high HbA1c groups, but CVD mortality increased only in high HbA1c group. In particular, people with liver diseases and low HbA1c levels had a high risk of all-cause mortality. Therefore, more careful management of these groups is suggested to identify any deteriorating health conditions.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00682-4.

Cardiovascular events and atherosclerosis in patients with type 2 diabetes and impaired glucose tolerance -What are the medical treatments to prevent cardiovascular events in such patients?

Type 2 diabetes mellitus (T2DM) and impaired glucose tolerance (IGT) significantly induce advanced coronary artery disease and systemic atherosclerosis. Thus, T2DM and IGT are traditional risk factors of cardiovascular disease (CVD). On the other hand, acute coronary syndrome is frequently caused by the rupture of coronary atherosclerotic plaques, which reduces patients' quality of life and may result in death. To date, many trials have sought to identify ways to determine the coronary plaque volume and its vulnerability, and many studies have demonstrated that some specific antihyperglycemic agents may prevent coronary or carotid plaque progression, decrease plaque volume, induce plaque stability, and improve clinical outcomes in patients with T2DM and IGT. This article reviews i) the association between coronary or carotid plaques and abnormal glucose tolerance, including T2DM; and ii) the effects of oral antihyperglycemic drugs to improve clinical outcomes and stabilize atherosclerotic plaques in patients with T2DM and IGT.

Prediabetes and What It Means: The Epidemiological Evidence

Prediabetes is an intermediate stage between normal glycemia and diabetes and is highly prevalent, especially in older age groups and obese individuals. Five different definitions of prediabetes are used in current practice, which are based on different cut points of HbA_1C, fasting glucose, and 2-h glucose. A major challenge for the field is a lack of guidance on when one definition might be preferred over another. Risks of major complications in persons with prediabetes, including diabetes, cardiovascular disease, kidney disease, and death, also vary depending on the prediabetes definition used. Randomized clinical trials have demonstrated that lifestyle and pharmacologic interventions can be cost-effective, prevent diabetes, and improve cardiovascular risk factors in adults with prediabetes. However, the practical implementation of lifestyle modification or the use of metformin for treating prediabetes is inadequate and complicated by a lack of agreement on how to define the condition. Establishing consensus definitions for prediabetes should be a priority and will help inform expansion of insurance coverage for lifestyle modification and improve current screening and diagnostic practices.

Prediabetes Defined by First Measured HbA1c Predicts Higher Cardiovascular Risk Compared With HbA1c in the Diabetes Range: A Cohort Study of Nationwide Registries

OBJECTIVE

To assess the risk of major adverse cardiovascular events (MACE), all-cause mortality, and initiation of medical treatment in subjects with prediabetes according to first-time measured HbA_1c.

RESEARCH DESIGN AND METHODS

Through registry databases, we identified 326,305 Danish patients with a first HbA_1c between 40 and 51 mmol/mol (5.8-6.8%) from 2011 to 2017. After exclusion of patients with prior disease, 84,678 patients were followed 12 months after first HbA_1c measurement. Cox regression models were used to estimate hazard ratios (HRs) of MACE and standardized absolute risks. Cumulative incidences were used to analyze initiation of glucose-lowering, antihypertensive, cholesterol-lowering, and antithrombotic medication.

RESULTS

The 12-month risk of MACE and all-cause mortality increased gradually with increasing HbA_1c until 47 mmol/mol (6.5%). In comparisons of subjects with HbA_1c 40-41 mmol/mol (5.8-5.9%), subjects with HbA_1c 46-47 mmol/mol (6.4-6.5%) had a 0.79% (95% CI 0.33-1.24) higher standardized absolute risk and an HR of 2.21 (95% CI 1.67-2.92) of MACE. Patients with HbA_1c 48-49 mmol/mol (6.5-6.6%) had a 0.09% (95% CI -0.35 to 0.52) lower absolute risk and an HR of 1.33 (95% CI 0.87-2.05) of MACE. Initiation of medication was significantly lower among patients with HbA_1c of 46-47 mmol/mol (6.4-6.5%) than among patients with HbA_1c of 48-49 mmol/mol (6.5-6.6%).

CONCLUSIONS

In the Danish population screened for diabetes with HbA_1c, the highest risk of MACE and all-cause mortality was found in subjects with HbA_1c just below the diagnostic threshold for diabetes. Our results highlight the need for increased focus on the treatment of cardiovascular risk factors for subjects with prediabetes.

Left ventricular myocardial performance index in prediabetic patients without coronary artery disease

Background

Prediabetes is considered a major risk factor for diabetes mellitus (DM), leading to microvascular and cardiovascular disorders. Myocardial performance index (MPI) is a non-invasive Doppler method for the determination of global ventricular activity. We have not enough knowledge about the effect of prediabetes on the left ventricular (LV) function. We aimed to assess the MPI in prediabetic patients without coronary artery disease (CAD) utilizing echocardiography tissue Doppler imaging (TDI).

Results

We conducted a randomized controlled study that included fifty prediabetic patients and fifty healthy participants as the control group. All the participants were subjected to laboratory tests and echocardiography TDI to evaluate the LV systolic and diastolic functions

We found that the isovolumic relaxation time (IVRT) and MPI values were significantly increased in the prediabetic patients compared to the control group (P < 0.001). In contrast, left ventricular ejection time (ET) was significantly longer in the control group than in prediabetic patients.

Conclusion

Prediabetes may adversely affect the LV function as assessed by MPI. Screening for prediabetes and early intervention is required for the prevention of cardiovascular morbidity and mortality.

Time in Range Is Associated with Carotid Intima-Media Thickness in Type 2 Diabetes

Background: Time in range (TIR) is an emerging metric of glycemic control and is reported to be associated with microvascular complications of diabetes. We sought to investigate the association of TIR obtained from continuous glucose monitoring (CGM) with carotid intima-media thickness (CIMT) as a surrogate marker of cardiovascular disease (CVD). Methods: Data from 2215 patients with type 2 diabetes were cross-sectionally analyzed. TIR of 3.9-10.0 mmol/L was evaluated with CGM. CIMT was measured using high-resolution B-mode ultrasonography and abnormal CIMT was defined as a mean CIMT ≥1.0 mm. Logistic regression models were used to examine the independent association of TIR with CIMT. Results: Compared with patients with normal CIMT, those with abnormal CIMT had significantly lower TIR (P < 0.001). The prevalence of abnormal CIMT progressively decreased across the categories of increasing TIR (P for trend <0.001). In a fully adjusted model controlling for traditional risk factor of CVD, each 10% increase in TIR was associated with 6.4% lower risk of abnormal CIMT. Stratifying the data by sex revealed that TIR was significantly associated with CIMT in males but not in females. In a subset of patients (n = 612) with complete data on diabetic retinopathy and albuminuria, we found that the relationship between TIR and CIMT remained to be significant, regardless of the status of microvascular complications. Conclusions: TIR is associated with CIMT in a large sample of patients with type 2 diabetes, suggesting a link between TIR and macrovascular disease.

Elevated 1-h postload plasma glucose levels identify coronary heart disease patients with greater severity of coronary artery lesions and higher risk of 1-year re-admission

OBJECTIVE

To investigate the relationship of 1-h postload plasma glucose during the oral glucose tolerance test with the severity of coronary artery lesions and risk of 1-year re-admission in coronary heart disease patients with normal glucose tolerance.

METHODS

A total of 266 consecutive coronary heart disease patients who underwent coronary angiography and had normal glucose tolerance confirmed by oral glucose tolerance test during hospitalization were prospectively enrolled and followed in two groups according to the 1-h postload plasma glucose cut-off point (1-h postload plasma glucose <155 mg/dL, n = 149 and 1-h postload plasma glucose ⩾155 mg/dL, n = 117). Angiographic severity was assessed by number of diseased vessels, lesion morphology and Gensini score. The risk of 1-year re-admission with adverse cardiovascular events after discharge was analysed.

RESULTS

Subjects with a 1-h postload plasma glucose ⩾155 mg/dL had higher incidence of multivessel disease and complex lesions, Gensini score and risk of 1-year re-admission than subjects with a 1-h postload plasma glucose <155 mg/dL (all p < 0.05). In the stepwise multivariate regression analysis, 1-h postload plasma glucose was the major determinant of the Gensini score. Subgroup analyses by sex showed that men with a 1-h postload plasma glucose ⩾155 mg/dL had higher incidence of complex lesions and risk of 1-year re-admission than men with a 1-h postload plasma glucose <155 mg/dL (all p < 0.05).

CONCLUSION

Coronary heart disease patients with normal glucose tolerance and elevated 1-h postload plasma glucose levels had a greater severity of coronary artery lesions and an increased risk of re-admission with adverse cardiovascular events, particularly in men.

Risk factor reduction in type 2 diabetes demands a multifactorial approach

Dysglycaemia (i.e. type 2 diabetes mellitus or impaired glucose tolerance) is not only common in patients with cardiovascular disease but increases the risk for future cardiovascular complications. Hyperglycaemia, the hallmark of diabetes, has since long been considered to be the link between diabetes and cardiovascular disease. Diabetes is, however, a complex, multifactorial disorder to which, for example, insulin resistance, endothelial dysfunction and factors such as increased thrombogenicity, hypertension and dyslipidaemia contribute. Thus, treatment needs to be multifactorial and to take cardiovascular aspects into account. Life-style adjustments are, together with blood pressure, lipid and glucose control, important parts of such management. Recent trial data reveal a beneficial effect on cardiovascular prognosis and mortality of blood glucose lowering agents belonging to the classes: sodium-glucose-transporter 2 inhibitors and glucagon-like peptide 1 agonists. The precise mechanisms by which certain sodium-glucose-transporter 2 inhibitors and glucagon-like peptide receptor agonists lead to these beneficial effects are only partly understood. An important impact of the benefits of sodium-glucose-transporter 2 inhibitors is a reduction in heart failure while glucagon-like peptide receptor agonists may retard the development of atherosclerotic vascular disease or stabilising plaques. Although there has been a considerable improvement in the prognosis for people with atherosclerotic diseases over the last decades there is still a gap between those with dysglycaemia, who are at higher risk, than those without dysglycaemia. This residual risk is reasonably related to two major factors: a demand for improved management and a need for new and improved therapeutic opportunities of type 2 diabetes, both routes to an improved prognosis that are at hands. This review is a comprehensive description of the possibilities to improve the prognosis for patients with dysglycaemia by a multifactorial management according to the most recent European guidelines issued in 2019 by the European Society of Cardiology in collaboration with the European Association for the Study of Diabetes.

Fasting Blood Glucose and HbA1c Correlate With Severity of Coronary Artery Disease in Elective PCI Patients With HbA1c 5.7% to 6.4

Diabetes mellitus, and even prediabetes, has been shown to be independently associated with cardiovascular disease. Our study explored whether the combination of glycosylated hemoglobin (HbA_1c) and fasting blood glucose (FBG) can better assess the severity of coronary heart disease (CHD) in elective percutaneous coronary intervention (PCI) patients. We consecutively enrolled 1006 prediabetic patients with HbA_1c 5.7% to 6.4% who underwent elective PCI. Patients were divided into 2 groups: a normal fasting glucose (NFG) group (FBG <6.1 mmol/L) and an impaired fasting glucose (IFG) group (6.1 ≤FBG<7.0 mmol/L) with defined values. Baseline characteristics and angiography data of the 2 groups were compared. The prevalence of 3-vessel disease (P = .002), the GENSINI (the score is named after a professor) score (P = .002), and the SYNTAX (SYNergy between PCI with TAXUS™ and Cardiac Surgery) score (P = .002) of the IFG group was significantly higher compared to the NFG group. After multiple regression analysis, FBG was found to be independently associated with prevalence of 3-vessel disease (adjusted odds ratio: 1.62; 95% confidence interval: 1.21-2.36; P = .013), the GENSINI score (standardized β = .138, P = .008), and the SYNTAX score (standardized β = .145, P = .005). In addition, HbA_{1 c} was independently associated with the prevalence of 3-vessel disease, the GENSINI, score, and the SYNTAX score (P < .05). Both FBG and HbA_1c are independently correlated with the severity of CHD in prediabetic patients with HbA_1c 5.7% to 6.4%.

Association of Concurrent Changes in Metabolic Health and Weight on Cardiovascular Disease Risk: A Nationally Representative Cohort Study

Background

The combined effect of transitions of metabolic health and weight on cardiovascular disease (CVD) remains unclear. We aimed to examine the association of concurrent changes of metabolic health and weight on CVD over time.

Methods and Results

The study population consisted of 205 394 from the Korean National Health Insurance Service. Metabolic health was determined by fasting serum glucose, total cholesterol, and blood pressure levels, while obesity was determined by body mass index. All participants were divided into either metabolically healthy nonobese (MHNO), metabolically healthy obese, metabolically unhealthy nonobese, or metabolically unhealthy obese for each of the first (2002–2003) and second (2004–2005) health screening periods, after which participants were followed‐up for CVD from 2006 to 2015. Cox proportional hazards regression was used to determine adjusted hazard ratios (aHRs) and 95% CIs. Among initial MHNO participants, those who became metabolically healthy obese (aHR, 1.25; 95% CI, 1.10–1.41), metabolically unhealthy nonobese (aHR, 1.23; 95% CI, 1.15–1.31), and metabolically unhealthy obese (aHR, 1.34; 95% CI, 1.12–1.61) had elevated risk for CVD compared with those who remained MHNO. Conversely, improving metabolic health and obesity were associated with reduced CVD risk among initially metabolically unhealthy nonobese to secondary MHNO (aHR, 0.79; 95% CI, 0.73–0.84), metabolically unhealthy obese to MHNO (aHR, 0.68; 95% CI, 0.58–0.81), and metabolically unhealthy obese to metabolically healthy obese (aHR, 0.73; 95% CI, 0.66–0.80) participants.

Conclusions

Changes toward metabolically unhealthy or obese states resulted in increased CVD risk. Improving metabolic health along with reducing weight may lead to decreased risk of CVD.

Predictive Value of Fasting Glucose, Postload Glucose, and Hemoglobin A1c on Risk of Diabetes and Complications in Chinese Adults

OBJECTIVE

Uncertainty remains regarding the predictive value of various glycemic measures as they relate to the risk of diabetes and its complications. Using the cutoffs recommended by the American Diabetes Association's 2010 criteria, we determined the associations of fasting plasma glucose (FPG), 2-h postload glucose (2h-PG), and HbA_1c with the outcomes.

RESEARCH DESIGN AND METHODS

Baseline medical history, FPG, 2h-PG, and HbA_1c were obtained from a population-based cohort of 193,846 adults aged ≥40 years in China during 2011-2012. A follow-up visit was conducted during 2014-2016 in order to assess incident diabetes, cardiovascular disease (CVD), cancer, and mortality.

RESULTS

We documented 8,063 cases of diabetes, 3,014 CVD-related events, 1,624 cases of cancer, and 2,409 deaths during up to 5 years of follow-up. Multivariable-adjusted risk ratios (95% CIs) of diabetes associated with prediabetes based on FPG of 100-125 mg/dL, 2h-PG of 140-199 mg/dL, or HbA_1c of 5.7-6.4% (39-47 mmol/mol) were 1.60 (1.43-1.79), 2.72 (2.43-3.04), and 1.49 (1.36-1.62), respectively. Restricted cubic spline analyses suggested J-shaped associations of FPG, 2h-PG, and HbA_1c levels with CVD, cancer, and mortality. Multivariable-adjusted hazard ratios (95% CIs) associated with untreated diabetes based on FPG ≥126 mg/dL, 2h-PG ≥200 mg/dL, or HbA_1c ≥6.5% (48 mmol/mol) were 1.18 (1.05-1.33), 1.31 (1.18-1.45), and 1.20 (1.07-1.34) for CVD; 1.10 (0.92-1.32), 1.44 (1.25-1.67), and 1.08 (0.92-1.28) for cancer; and 1.37 (1.20-1.57), 1.57 (1.41-1.76), and 1.33 (1.17-1.52) for mortality, respectively. 2h-PG remained significantly associated with outcomes in models including FPG and HbA_1c as spline terms. Furthermore, 2h-PG significantly improved the ability of the C statistic to predict diabetes, CVD, and mortality.

CONCLUSIONS

2h-PG remains independently predictive of outcomes in models including FPG and HbA_1c. Therefore, in addition to FPG and HbA_1c, routine testing of 2h-PG should be considered in order to better assess the risks of outcomes.

Fasting glucose and its association with 20-year all-cause and cause-specific mortality in Chinese general population

Objective

The aim of this study was to explore the relationship between fasting glucose levels and all-cause and cause-specific mortality in Chinese population.

Methods

The role of fasting blood glucose levels as a predictor of all-cause and cause-specific mortality was estimated in 9930 participants from four Chinese general populations with a 20-year follow-up. Multivariate Cox proportional hazard models were used to identify the relationship between fasting glucose and mortality.

Results

There were 1471 deaths after a median follow-up of 20.2 years (a total of 187,374 person-years), including 310 cardiovascular deaths, 581 cancer deaths, and 580 other-cause deaths. After adjustment for age, sex, urban or rural, northern or southern of China, types of work, education level, physical exercise, smoking status, drinking status, body mass index, systolic blood pressure, and serum total cholesterol at baseline, the hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality in the fasting blood glucose categories of <60, 60-69, 70-79, 90-99, 100-109, 110-125, and ≥126 mg/dl were 1.38 (1.04-1.84), 1.20 (1.01-1.43), 1.18 (1.03-1.36), 1.18 (0.99-1.41), 1.48 (1.16-1.88), 1.17 (0.84-1.62), and 2.23 (1.72-2.90), respectively, in contrast to the reference group (80-89 mg/dl). The HRs and 95% CIs for cardiovascular disease mortality in these groups were 2.58 (1.44-4.61), 1.41 (0.95-2.10), 1.56 (1.15-2.11), 1.29 (0.88-1.89), 1.36 (0.78-2.37), 1.05 (0.52-2.11), and 2.73 (1.64-4.56), respectively.

Conclusions

Both low and high fasting glucose were significantly associated with increased risk of all-cause and cardiovascular mortality in Chinese general population.

Risk of Cardiovascular Disease and Death in Individuals With Prediabetes Defined by Different Criteria: The Whitehall II Study

OBJECTIVE

We compared the risk of cardiovascular disease (CVD) and all-cause mortality in subgroups of prediabetes defined by fasting plasma glucose (FPG), 2-h plasma glucose (2hPG), or HbA_1c.

RESEARCH DESIGN AND METHODS

In the Whitehall II cohort, 5,427 participants aged 50-79 years and without diabetes were followed for a median of 11.5 years. A total of 628 (11.6%) had prediabetes by the World Health Organization (WHO)/International Expert Committee (IEC) criteria (FPG 6.1-6.9 mmol/L and/or HbA_1c 6.0-6.4%), and 1,996 (36.8%) by the American Diabetes Association (ADA) criteria (FPG 5.6-6.9 mmol/L and/or HbA_1c 5.7-6.4%). In a subset of 4,730 individuals with additional measures of 2hPG, 663 (14.0%) had prediabetes by 2hPG. Incidence rates of a major event (nonfatal/fatal CVD or all-cause mortality) were compared for different definitions of prediabetes, with adjustment for relevant confounders.

RESULTS

Compared with that for normoglycemia, incidence rate in the context of prediabetes was 54% higher with the WHO/IEC definition and 37% higher with the ADA definition (P < 0.001) but declining to 17% and 12% after confounder adjustment (P ≥ 0.111). Prediabetes by HbA_1c was associated with a doubling in incidence rate for both the IEC and ADA criteria. However, upon adjustment, excess risk was reduced to 13% and 17% (P ≥ 0.055), respectively. Prediabetes by FPG or 2hPG was not associated with an excess risk in the adjusted analysis.

CONCLUSIONS

Prediabetes defined by HbA_1c was associated with a worse prognosis than prediabetes defined by FPG or 2hPG. However, the excess risk among individuals with prediabetes is mainly explained by the clustering of other cardiometabolic risk factors associated with hyperglycemia.

Higher serum albumin was related with diabetes incidence and the impact of BMI changes: Based on cohort study of 18,384 Chinese male elderly

AIMS

Albumin (ALB) was a useful marker of nutrition and general health status. However, the conclusion about the association between ALB and diabetes was inconsistent, and little information was known about the elderly.

METHODS

A cohort study based on 18,384 army cadres was conducted Beijing, from 2009 to 2013.

RESULTS

The mean age of the total 18,384 participants was 71±14years, and the mean ALB concentration was 44.33±3.94g/L at baseline. Diabetes incident showed an increasing trend according to the four ALB concentration groups, from 2.054% to 2.811% for incident. Cox regression showed that participants with higher ALB concentration were at increased HRs for diabetes incident. The HRs of ALB (per SD) and ALB concentration for diabetes were 1.125 (95% CI: 1.024-1.231) and 1.029 (95% CI: 1.007-1.051) respectively in the adjusted model. Also the HRs were closely related with BMI changes. For those who had a BMI changes<-1.00kg/m², the HRs were lower and not statistically significant, and for those with increasing BMI during an average of 4years' follow-up, the HRs were higher.

CONCLUSION

There was a positive and independent association between baseline ALB concentrations with diabetes incident among Chinese male elderly, and this association was closely related with BMI changes.

Effect of post-cessation hyperglycemia on cardiovascular disease and mortality among middle-aged men: an eight-year longitudinal study

Smoking cessation reduces the risk of cardiovascular disease (CVD), but also elevates fasting serum glucose (FSG) levels. The effect of post-cessation hyperglycemia on cardiovascular disease is unknown. The study population consisted of 127,066 men without type 2 diabetes from the Korean National Health Insurance System – Health Screening Cohort database. Change in smoking habits and FSG was determined by the difference in smoking status and FSG levels from the first (2002 and 2003) and second (2004 and 2005) health examinations. Continual smokers, quitters, ex-smokers, and never smokers were stratified according to FSG elevation. The study participants were followed-up for CVD and CVD-related death from 2006 to 2013. Compared to continual smokers, quitters had decreased risk of CVD among those without FSG elevation (hazard ratio, HR, 0.76, 95% confidence interval, CI, 0.66–0.86) and with FSG elevation (HR 0.83, 95% CI 0.72–0.96). Similarly, quitters had a tendency towards reduced risk of CVD-related death among those without FSG elevation (HR 0.74, 95% CI 0.51–1.09) and with FSG elevation (HR 0.68, 95% CI 0.46–1.03). Post-cessation hyperglycemia did not attenuate the beneficiary risk-reducing effects of quitting on CVD and CVD-related death.

Predictors of all-cause mortality among 514,866 participants from the Korean National Health Screening Cohort

Background

There is not enough evidence regarding how information obtained from general health check-ups can predict individual mortality based on long-term follow-ups and large sample sizes. This study evaluated the applicability of various health information and measurements, consisting of self-reported data, anthropometric measurements and laboratory test results, in predicting individual mortality.

Methods

The National Health Screening Cohort included 514,866 participants (aged 40–79 years) who were randomly selected from the overall database of the national health screening program in 2002–2003. Death was determined from causes of death statistics provided by Statistics Korea. We assessed variables that were collected at baseline and repeatedly measured for two consecutive years using traditional and time-variant Cox proportional hazards models in addition to random forest and boosting algorithms to identify predictors of 10-year all-cause mortality. Participants’ age at enrollment, lifestyle factors, anthropometric measurements and laboratory test results were included in the prediction models. We used c-statistics to assess the discriminatory ability of the models, their external validity and the ratio of expected to observed numbers to evaluate model calibration. Eligibility of Medicaid and household income levels were used as inequality indexes.

Results

After the follow-up by 2013, 38,031 deaths were identified. The risk score based on the selected health information and measurements achieved a higher discriminatory ability for mortality prediction (c-statistics = 0.832, 0.841, 0.893, and 0.712 for Cox model, time-variant Cox model, random forest and boosting, respectively) than that of the previous studies. The results were externally validated using the community-based cohort data (c-statistics = 0.814).

Conclusions

Individuals’ health information and measurements based on health screening can provide early indicators of their 10-year death risk, which can be useful for health monitoring and related policy decisions.

Can Cardiovascular Epidemiology and Clinical Trials Close the Risk Management Gap Between Diabetes and Prediabetes?

PURPOSE OF REVIEW

We reviewed published literature to determine the relationship between A1c and cardiovascular disease (CVD) and summarize the need and implications for CVD risk reduction with interventions, focusing in the prediabetic A1c range (<6.5%).

RECENT FINDINGS

Strong evidence supports a continuous relationship between A1c and CVD-even below the current levels of A1c-defined prediabetes and after adjustment for known risk factors for CVD. Clinical trials have demonstrated a reduction in CV morbidity and/or mortality when interventions are invoked in the prediabetic A1c range. Guidelines advocating CV risk factor management in prediabetes have not been widely adopted, subsequently leading to comparable coronary heart disease risk between people with prediabetes (HR = 1.9, 95% CI 1.7-2.1 vs normoglycemia) and diabetes itself (HR=2.0, 95% CI 1.8-2.2 vs no diabetes). This review highlights the missed opportunity to utilize multiple risk factor interventions to reduce CVD in high-risk people with prediabetes.

The Prognostic Value of Fasting Plasma Glucose, Two-Hour Postload Glucose, and HbA1c in Patients With Coronary Artery Disease: A Report From EUROASPIRE IV: A Survey From the European Society of Cardiology

OBJECTIVE

Three tests are recommended for identifying dysglycemia: fasting glucose (FPG), 2-h postload glucose (2h-PG) from an oral glucose tolerance test (OGTT), and glycated hemoglobin A1c (HbA1c). This study explored the prognostic value of these screening tests in patients with coronary artery disease (CAD).

RESEARCH DESIGN AND METHODS

FPG, 2h-PG, and HbA1c were used to screen 4,004 CAD patients without a history of diabetes (age 18-80 years) for dysglycemia. The prognostic value of these tests was studied after 2 years of follow-up. The primary end point included cardiovascular mortality, nonfatal myocardial infarction, stroke, or hospitalization for heart failure and a secondary end point of incident diabetes.

RESULTS

Complete information including all three glycemic parameters was available in 3,775 patients (94.3%), of whom 246 (6.5%) experienced the primary end point. Neither FPG nor HbA1c predicted the primary outcome, whereas the 2h-PG, dichotomized as <7.8 vs. ≥7.8 mmol/L, was a significant predictor (hazard ratio 1.38, 95% CI 1.07-1.78; P = 0.01). During follow-up, diabetes developed in 78 of the 2,609 patients (3.0%) without diabetes at baseline. An FPG between 6.1 and 6.9 mmol/L did not predict incident diabetes, whereas HbA1c 5.7-6.5% and 2h-PG 7.8-11.0 mmol/L were both significant independent predictors.

CONCLUSIONS

The 2h-PG, in contrast to FPG and HbA1c, provides significant prognostic information regarding cardiovascular events in patients with CAD. Furthermore, elevated 2h-PG and HbA1c are significant prognostic indicators of an increased risk of incident diabetes.

HbA1c in relation to incident diabetes and diabetes-related complications in non-diabetic adults at baseline

AIMS

We compared the utility of glycated hemoglobin (HbA_1c) and oral glucose tolerance (oGTT) in non-diabetic patients for identifying incident diabetes; all-cause mortality; cardiovascular disease (CVD) mortality; CVD, coronary heart disease (CHD), and ischemic stroke events; and diabetes microvascular complications.

METHODS

Data from a New Zealand community setting were prospectively linked to hospitalization, mortality, pharmaceutical and laboratory test results data. After applying exclusion criteria (prior laboratory diagnosis or history of drug treatment for diabetes or hospitalization for diabetes or CVD event), there were 31,148 adults who had an HbA_1c and 2-h 75g oGTT. HbA_1c was measured by ion-exchange high-performance liquid chromatography, and glucose using a commercial enzymatic method. We compared glycemic measures and outcomes using multivariable Cox proportional hazards regression.

RESULTS

The median follow-up time was 4years (range 0 to 13). The mean age was 57·6years and 53·0% were male. After adjusting for other glycemic measures (fasting glucose, 2-h glucose and/or HbA_1c where relevant) in addition to age, sex, ethnicity and smoking habit, the hazard ratios for incident diabetes and diabetes complications of retinopathy and nephropathy were highest for 2-h glucose levels, followed by HbA_1c and lastly by fasting glucose. However, all-cause mortality and CHD were significantly associated with HbA_1c concentrations only, and ischemic stroke and CVD events with 2-h glucose only. Circulatory complications showed a stronger association with HbA_1c.

CONCLUSION

Apart from neuropathy, HbA_1c showed stronger associations with outcomes compared to fasting glucose and provides a convenient alternative to an oGTT.

Nutritional intervention and impact of polyphenol on glycohemoglobin (HbA1c) in non-diabetic and type 2 diabetic subjects: Systematic review and meta-analysis

Polyphenols have been extensively studied for their antioxidant and anti-inflammatory properties. Recently, their antiglycative actions by oxidative stress modulation have been linked to the prevention of diabetes and associated complications. This article assesses the evidence for polyphenol interventions on glycohemoglobin (HbA1c) in non-diabetic, pre-diabetic, and type 2 diabetes mellitus (T2DM) subjects. A systematic review of polyphenols' clinical trials on HbA1c in humans was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis. Thirty-six controlled randomized trials with HbA1c values were included. Polyphenols (extracts, supplements, and foods) were supplemented (28 mg to 1.5 g) for 0.7 to 12 months. Combining all subjects (n = 1954, mean baseline HbA1c = 7.03%, 53 mmol/mol), polyphenol supplementation significantly (P < 0.001) lowered HbA1c% by -0.53 ± 0.12 units (-5.79 ± 0.13 mmol/mol). This reduction was significant (P < 0.001) in T2DM subjects, specifically (n = 1426, mean baseline HbA1c = 7.44%, 58 mmol/mol), with HbA1c% lowered by -0.21 ± 0.04 units (-2.29 ± 0.4 mmol/mol). Polyphenol supplementation had no significant effect (P > 0.21) in the non-diabetic (n = 258, mean baseline HbA1c = 5.47%, 36 mmol/mol) and the pre-diabetic subjects (n = 270, mean baseline HbA1c = 6.06%, 43 mmol/mol) strata: -0.39 ± 0.27 HbA1c% units (-4.3 ± 0.3 mmol/mol), and -0.38 ± 0.31 units (-4.2 ± 0.31 mmol/mol), respectively. In conclusion, polyphenols can successfully reduce HbA1c in T2DM without any intervention at glycemia, and could contribute to the prevention of diabetes complications.

Low fructosamine and mortality - A long term follow-up of 215,011 non-diabetic subjects in the Swedish AMORIS study

BACKGROUND AND AIMS

Both high and low fasting glucose has been associated with an increased mortality among individuals without diabetes. This J-shaped association has also been shown for HbA1c in relation to all-cause mortality. High fructosamine is associated with increased mortality. In this study we aim to evaluate if low fructosamine is also associated with increased mortality in non-diabetic subjects.

METHODS AND RESULTS

We included 215,011 subjects from the AMORIS cohort undergoing occupational health screening or primary care in Stockholm, Sweden. Cause specific mortality was obtained from the Swedish Cause-of-Death Register by record linkage. Hazard ratios for the lowest decile of fructosamine were estimated by Cox regression for all-cause (n = 41,388 deaths) and cause-specific mortality during 25 years of follow-up. We observed gradually increased mortality with lower fructosamine in a large segment of the population. In the lowest decile of fructosamine the sex, age, social class and calendar adjusted hazard ratio was 1.20 (95% CI; 1.18-1.27) compared to deciles 2-9. This increased mortality was attenuated after adjustment for six other biomarkers (HR = 1.11 (95% CI; 1.07-1.15)). Haptoglobin, an indicator of chronic inflammation, made the greatest difference in the point estimate. In sensitivity analyses we found an association between low fructosamine and smoking and adjustment for smoking further attenuated the association between low fructosamine and mortality.

CONCLUSION

Low levels of fructosamine in individuals without diabetes were found to be associated with increased mortality. Smoking and chronic inflammation seem to at least partially explain this association but an independent contribution by low fructosamine cannot be excluded.

Rationale and design of a multicenter randomized controlled study to evaluate the preventive effect of ipragliflozin on carotid atherosclerosis: the PROTECT study

BACKGROUND

Type 2 diabetes mellitus is associated strongly with an increased risk of micro- and macro-vascular complications, leading to impaired quality of life and shortened life expectancy. In addition to appropriate glycemic control, multi-factorial intervention for a wide range of risk factors, such as hypertension and dyslipidemia, is crucial for management of diabetes. A recent cardiovascular outcome trial in diabetes patients with higher cardiovascular risk demonstrated that a SGLT2 inhibitor markedly reduced mortality, but not macro-vascular events. However, to date there is no clinical evidence regarding the therapeutic effects of SGLT2 inhibitors on arteriosclerosis. The ongoing PROTECT trial was designed to assess whether the SGLT2 inhibitors, ipragliflozin, prevented progression of carotid intima-media thickness in Japanese patients with type 2 diabetes mellitus.

METHODS

A total of 480 participants with type 2 diabetes mellitus with a HbA1c between 6 and 10 % despite receiving diet/exercise therapy and/or standard anti-diabetic agents for at least 3 months, will be randomized systematically (1:1) into either ipragliflozin or control (continuation of conventional therapy) groups. After randomization, ipragliflozin (50-100 mg once daily) will be added on to the background therapy in participants assigned to the ipragliflozin group. The primary endpoint of the study is the change in mean intima-media thickness of the common carotid artery from baseline to 24 months. Images of carotid intima-media thickness will be analyzed at a central core laboratory in a blinded manner. The key secondary endpoints include the change from baseline in other parameters of carotid intima-media thickness, various metabolic parameters, and renal function. Other cardiovascular functional tests are also planned for several sub-studies.

DISCUSSION

The PROTECT study is the first to assess the preventive effect of ipragliflozin on progression of carotid atherosclerosis using carotid intima-media thickness as a surrogate marker. The study has potential to clarify the protective effects of ipragliflozin on atherosclerosis. Trial registration Unique Trial Number, JPRN/UMIN000018440 ( https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000021348 ).

Fasting plasma glucose levels and coronary artery calcification in subjects with impaired fasting glucose

BACKGROUND

Prediabetes is associated with an increased risk of cardiovascular disease (CVD). While the association of impaired glucose tolerance with CVD has been shown in many studies, the relationship between impaired fasting glucose (IFG) and CVD remains unclear.

OBJECTIVES

The purpose of this study was to compare the coronary artery calcium (CAC) scores of participants with normal fasting glucose versus those with IFG, according to fasting plasma glucose (FPG) levels, and to assess whether differences in CAC scores were independent of important confounders.

DESIGN

Retrospective study.

SETTING

Health Promotion Center of the University Hospital (Gyeonggi-do, South Korea), during the period 2010-2014.

PATIENTS AND METHODS

Participants were enrolled from the general population who visited for a medical check-up. CAC was assessed in asymptomatic individuals by multidetector computed tomography. Anthropometric parameters and metabolic profiles were also recorded. Subjects were divided into four fasting glucose groups. Participants with a history of CVD or diabetes mellitus were excluded.

MAIN OUTCOME MEASURES

Correlation between FPG and CAC scores, CAC score categories, and association between CAC score and FPG categories.

RESULTS

Of 1112 participants, 346 (34.2%) had a CAC score > 0. FPG values in the IFG patients were positively but weakly correlated with CAC scores (r=0.099, P=.001). The incidence of CAC differed according to FPG level (P < .001) and in Kruskal-Wallis test the mean CAC score differed by FPG group (P < .001). After adjustment for other factors in a multiple logistic regression analysis, those subjects with FPG >=110 mg/dL had a significantly higher risk of CAC than did subjects with normal fasting glucose (110.

Assessment of the left ventricular function in normotensive prediabetics: a tissue Doppler echocardiography study

OBJECTIVE

Several studies have shown that left ventricular (LV) dysfunction is increased in individuals with diabetes. However, there are scarce data about LV function in prediabetics. This study assessed the early changes in LV diastolic and systolic myocardial function in normotensive prediabetics using tissue Doppler echocardiography (TDE).

SUBJECTS AND METHODS

We evaluated 94 patients with prediabetes (mean age of 50.8 ± 6.9 years, 78 female) without known cardiovascular diseases and 70 healthy volunteers with similar demographic characteristics. Systolic and diastolic function of the left ventricle was evaluated with transthoracic echocardiography according to the latest consensus recommendations including TDE.

RESULTS

The mean results of septal and lateral parts of the mitral annulus Pulsed wave TDE showed that myocardial systolic wave (Sm), myocardial early diastolic wave (Em) and Em to atrial peak velocity (Am) ratio were significantly lower whereas early diastolic peak flow velocity (E) to Em ratio, myocardial isovolumetric relaxation time (IVRTm), myocardial isovolumetric contraction time (IVCTm) and myocardial performance index (MPI) values were significantly higher in patients with prediabetes (preDM). In addition, mean left atrium (LA) diameter measured with M-mode echocardiography was significantly higher in prediabetics than controls.

CONCLUSION

PreDM is associated with subclinical LV systolic and diastolic dysfunction as evaluated by TDE.

Prediction by Low Plasma HbA1c of Mortality, Cardiac and Noncardiac Disease Risk: Modulation by Diabetic Status and Sex

AIM

The aim of the study was to evaluate the predictive value of HbA(1c) for risk of overall mortality or a composite endpoint of death and nonfatal events.

METHODS

Logistic regression retrospectively assessed the longitudinal association of measured HbA(1c) with outcome in 746 middle-aged adults, recruited from a tertiary health center and stratified to absence or presence of type 2 diabetes, using the recent American Diabetes Association criteria.

RESULTS

A total of 70 deaths and additional incident nonfatal events in 82 cases were recorded at a median of 3.1-year follow-up. Multivariable linear regression revealed among nondiabetic individuals HbA(1c) to be significantly associated--independent of fasted glucose--inversely with triglycerides and high-density lipoprotein cholesterol, distinct from the diabetic sample. Sex and diabetes status differed in baseline HbA1c values with respect to the development of outcome. Nondiabetic men who subsequently died exhibited significantly lower HbA(1c), as did men and women with incident coronary heart disease. Similar difference was observed for incident hypothyroidism and nondiabetic subjects developing malignancy. In logistic regression analysis, adjusted for sex, age, and fasting glucose, each 0.7% (SD, 1) decrement of baseline HbA(1c) predicted the composite endpoint in the nondiabetic sample (risk estimates, 1.49%; 95% confidence interval, 1.07-2.04), but not in the diabetic sample, whereas overall mortality in the whole sample was increased (risk estimates, 1.51%; 95% confidence interval, 1.05-2.17).

CONCLUSIONS

Inverse association of HbA(1c) with adverse outcomes in men and nondiabetic people indicates the involvement of HbA(1c) levels in autoimmune activation. The weaker inverse association with prevalent diabetes and in women is consistent with the operation of more pronounced confounding autoimmune processes.

HbA1c levels in non-diabetic older adults - No J-shaped associations with primary cardiovascular events, cardiovascular and all-cause mortality after adjustment for confounders in a meta-analysis of individual participant data from six cohort studies

BACKGROUND

To determine the shape of the associations of HbA1c with mortality and cardiovascular outcomes in non-diabetic individuals and explore potential explanations.

METHODS

The associations of HbA1c with all-cause mortality, cardiovascular mortality and primary cardiovascular events (myocardial infarction or stroke) were assessed in non-diabetic subjects ≥50 years from six population-based cohort studies from Europe and the USA and meta-analyzed. Very low, low, intermediate and increased HbA1c were defined as <5.0, 5.0 to <5.5, 5.5 to <6.0 and 6.0 to <6.5% (equals <31, 31 to <37, 37 to <42 and 42 to <48 mmol/mol), respectively, and low HbA1c was used as reference in Cox proportional hazards models.

RESULTS

Overall, 6,769 of 28,681 study participants died during a mean follow-up of 10.7 years, of whom 2,648 died of cardiovascular disease. Furthermore, 2,493 experienced a primary cardiovascular event. A linear association with primary cardiovascular events was observed. Adjustment for cardiovascular risk factors explained about 50% of the excess risk and attenuated hazard ratios (95 confidence interval) for increased HbA1c to 1.14 (1.03-1.27), 1.17 (1.00-1.37) and 1.19 (1.04-1.37) for all-cause mortality, cardiovascular mortality and cardiovascular events, respectively. The six cohorts yielded inconsistent results for the association of very low HbA1c levels with the mortality outcomes and the pooled effect estimates were not statistically significant. In one cohort with a pronounced J-shaped association of HbA1c levels with all-cause and cardiovascular mortality (NHANES), the following confounders of the association of very low HbA1c levels with mortality outcomes were identified: race/ethnicity; alcohol consumption; BMI; as well as biomarkers of iron deficiency anemia and liver function. Associations for very low HbA1c levels lost statistical significance in this cohort after adjusting for these confounders.

CONCLUSIONS

A linear association of HbA1c levels with primary cardiovascular events was observed. For cardiovascular and all-cause mortality, the observed small effect sizes at both the lower and upper end of HbA1c distribution do not support the notion of a J-shaped association of HbA1c levels because a certain degree of residual confounding needs to be considered in the interpretation of the results.

Association of 1,5-Anhydroglucitol With Cardiovascular Disease and Mortality

In diabetes, low concentrations of the biomarker 1,5-anhydroglucitol (1,5-AG) reflect hyperglycemic excursions over the prior 1-2 weeks. To the extent that hyperglycemic excursions are important in atherogenesis, 1,5-AG may provide independent information regarding cardiovascular risk. Nonetheless, few studies have evaluated associations of 1,5-AG with long-term cardiovascular outcomes in a population-based setting. We measured 1,5-AG in 11,106 participants in the Atherosclerosis Risk in Communities (ARIC) study without cardiovascular disease at baseline (1990-1992) and examined prospective associations with coronary heart disease (n = 1,159 events), ischemic stroke (n = 637), heart failure (n = 1,553), and death (n = 3,120) over 20 years of follow-up. Cox proportional hazards models were adjusted for demographic and cardiovascular risk factors. Compared with persons with 1,5-AG ≥6 μg/mL and no history of diabetes, persons with diabetes and 1,5-AG <6.0 μg/mL had an increased risk of coronary heart disease (HR 3.85, 95% CI 3.11-4.78), stroke (HR 3.48, 95% CI 2.66-4.55), heart failure (HR 3.50, 95% CI 2.93-4.17), and death (HR 2.44, 95% CI 2.11-2.83). There was a threshold effect, with little evidence for associations at "nondiabetic" concentrations of 1,5-AG (e.g., >10 μg/mL). Associations remained but were attenuated with additional adjustment for fasting glucose or HbA1c. These data add to the growing evidence for the prognostic value of 1,5-AG for long-term complications in the setting of diabetes.

Elevated HbA(1c) levels and the accumulation of differentiated T cells in CMV(+) individuals

AIMS/HYPOTHESIS

Biological ageing of the immune system, or immunosenescence, predicts poor health and increased mortality. A hallmark of immunosenescence is the accumulation of differentiated cytotoxic T cells (CD27(-)CD45RA(+/-); or dCTLs), partially driven by infection with the cytomegalovirus (CMV). Immune impairments reminiscent of immunosenescence are also observed in hyperglycaemia, and in vitro studies have illustrated mechanisms by which elevated glucose can lead to increased dCTLs. This study explored associations between glucose dysregulation and markers of immunosenescence in CMV(+) and CMV(-) individuals.

METHODS

A cross-sectional sample of participants from an occupational cohort study (n = 1,103, mean age 40 years, 88% male) were assessed for HbA(1c) and fasting glucose levels, diabetes, cardiovascular risk factors (e.g. lipids), numbers of circulating effector memory (EM; CD27(-)CD45RA(-)) and CD45RA re-expressing effector memory (EMRA; CD27(-)CD45RA(+)) T cells, and CMV infection status. Self-report and physical examination assessed anthropometric, sociodemographic and lifestyle factors.

RESULTS

Among CMV(+) individuals (n = 400), elevated HbA(1c) was associated with increased numbers of EM (B = 2.75, p < 0.01) and EMRA (B = 2.90, p < 0.01) T cells, which was robust to adjustment for age, sex, sociodemographic variables and lifestyle factors. Elevated EM T cells were also positively associated with total cholesterol (B = 0.04, p < 0.05) after applying similar adjustments. No associations were observed in CMV(-) individuals.

CONCLUSIONS/INTERPRETATION

The present study identified consistent associations of unfavourable glucose and lipid profiles with accumulation of dCTLs in CMV(+) individuals. These results provide evidence that the impact of metabolic risk factors on immunity and health can be co-determined by infectious factors, and provide a novel pathway linking metabolic risk factors with accelerated immunosenescence.

Gender- and race-specific metabolic score and cardiovascular disease mortality in adults: A structural equation modeling approach--United States, 1988-2006

OBJECTIVE

Consider all metabolic syndrome (MetS) components [systolic (SBP) and diastolic (DBP) blood pressures, waist circumference, HDL cholesterol, triglycerides (TG), and fasting glucose] and gender/race differential risk when assessing cardiovascular disease (CVD) risk.

METHODS

We estimated a gender- and race-specific continuous MetS score using structural equation modeling and tested its association with CVD mortality using data from National Health and Nutrition Examination Survey III linked with the National Death Index. Cox proportional hazard regression tested the association adjusted for sociodemographic and behavior characteristics.

RESULTS

For men, continuous MetS components associated with CVD mortality were SBP (hazard ratio = 1.50, 95% confidence interval = 1.14-1.96), DBP (1.48, 1.16-1.90), and TG (1.15, 1.12-1.16). In women, SBP (1.44, 1.27-1.63) and DBP (1.24, 1.02-1.51) were associated with CVD mortality. MetS score was not significantly associated with CVD mortality in men; but significant associations were found for all women (1.34, 1.06-1.68), non-Hispanic white women (1.29, 1.01-1.64), non-Hispanic black women (2.03, 1.12-3.69), and Mexican-American women (3.57, 2.21-5.76). Goodness-of-fit and concordance were overall better for models with the MetS score than MetS (yes/no).

CONCLUSIONS

When assessing CVD mortality risk, MetS score provided additional information than MetS (yes/no).

Visceral fat area is associated with HbA1c but not dialysate-related glucose load in nondiabetic PD patients

Factors associated with increased visceral fat area (VFA) have been well documented in the general population but rarely explored in nondiabetic individuals on peritoneal dialysis (PD). As glycosylated hemoglobin (HbA1c) is positively correlated with VFA in diabetic patients, we hypothesized that the same correlation would exist in nondiabetic PD patients. We enrolled 105 nondiabetic patients who had undergone chronic PD for more than 3 months. Each subject underwent an abdominal computed tomography (CT) scan, and the umbilicus cut was analyzed for VFA. VFA values, corrected for body mass index and subjected to natural logarithm transformations, were examined to determine whether they were correlated with HbA1c and other parameters. PD dialysates prescribed at the time of enrollment were recorded to calculate glucose load. We found that when 105 nondiabetic PD patients were classified according to tertiles of HbA1c, higher HbA1c was associated with larger VFA. Multiple linear regression analysis revealed that HbA1c was an independent determinant of VFA, while glucose load and other PD-specific factors were not. In summary, HbA1c, but not PD-related glucose load, was positively correlated with VFA in nondiabetic PD patients, suggesting clinical utility of HbA1c in the PD population.

Association Between Glycosylated Hemoglobin and Cardiovascular Events and Mortality in Older Adults without Diabetes Mellitus in the General Population: The Leiden 85-Plus Study

OBJECTIVES

To examine the association between glycosylated hemoglobin (HbA1c) and incident cardiovascular disease and mortality in 85-year-old individuals without diabetes mellitus from the general population.

DESIGN

Population-based prospective follow-up study.

SETTING

General population.

PARTICIPANTS

Individuals without known diabetes mellitus (N = 445, n = 291 female).

MEASUREMENTS

HbA1c levels were categorized into three groups (<5.0% (31 mmol/mol), 5.0-5.7% (31-39 mmol/mol; reference), 5.7-6.5% (39-48 mmol/mol)).

RESULTS

At baseline, a history of myocardial infarction (MI) was more prevalent in subjects in the highest HbA1c group (18%) than in the reference group (7%) (P = .001). Prospectively, those with the highest level of HbA1c at baseline had a risk of incident MI during the 5-year follow-up that was 3.6 (95% confidence interval = 1.5-8.3) times as great as that of the reference group. No association was found between HbA1c level and incident stroke, cardiovascular mortality, or all-cause mortality.

CONCLUSION

In individuals aged 85 and older without diabetes mellitus, higher HbA1c is associated with greater risk of MI but not with stroke and mortality.