Implications of alternative definitions of prediabetes for prevalence in U.S. adults

International Diabetes Federation Position Statement on the 1-hour post-load plasma glucose for the diagnosis of intermediate hyperglycaemia and type 2 diabetes

Many individuals with intermediate hyperglycaemia (IH), including impaired fasting glycaemia (IFG) and impaired glucose tolerance (IGT), as presently defined, will progress to type 2 diabetes (T2D). There is confirmatory evidence that T2D can be prevented by lifestyle modification and/or medications, in people with IGT diagnosed by 2-h plasma glucose (PG) during a 75-gram oral glucose tolerance test (OGTT). Over the last 40 years, a wealth of epidemiological data has confirmed the superior value of 1-h plasma glucose (PG) over fasting PG (FPG), glycated haemoglobin (HbA1c) and 2-h PG in populations of different ethnicity, sex and age in predicting diabetes and associated complications including death. Given the relentlessly rising prevalence of diabetes, a more sensitive, practical method is needed to detect people with IH and T2D for early prevention or treatment in the often lengthy trajectory to T2D and its complications. The International Diabetes Federation (IDF) Position Statement reviews findings that the 1-h post-load PG ≥ 155 mg/dL (8.6 mmol/L) in people with normal glucose tolerance (NGT) during an OGTT is highly predictive for detecting progression to T2D, micro- and macrovascular complications, obstructive sleep apnoea, cystic fibrosis-related diabetes mellitus, metabolic dysfunction-associated steatotic liver disease, and mortality in individuals with risk factors. The 1-h PG of 209 mg/dL (11.6 mmol/L) is also diagnostic of T2D. Importantly, the 1-h PG cut points for diagnosing IH and T2D can be detected earlier than the recommended 2-h PG thresholds. Taken together, the 1-h PG provides an opportunity to avoid misclassification of glycaemic status if FPG or HbA1c alone are used. The 1-h PG also allows early detection of high-risk people for intervention to prevent progression to T2D which will benefit the sizeable and growing population of individuals at increased risk of T2D. Using a 1-h OGTT, subsequent to screening with a non-laboratory diabetes risk tool, and intervening early will favourably impact the global diabetes epidemic. Health services should consider developing a policy for screening for IH based on local human and technical resources. People with a 1-h PG ≥ 155 mg/dL (8.6 mmol/L) are considered to have IH and should be prescribed lifestyle intervention and referred to a diabetes prevention program. People with a 1-h PG ≥ 209 mg/dL (11.6 mmol/L) are considered to have T2D and should have a repeat test to confirm the diagnosis of T2D and then referred for further evaluation and treatment. The substantive data presented in the Position Statement provides strong evidence for redefining current diagnostic criteria for IH and T2D by adding the 1-h PG.

Prediabetes and Cardiometabolic Risk: The Need for Improved Diagnostic Strategies and Treatment to Prevent Diabetes and Cardiovascular Disease

The progression from prediabetes to type-2 diabetes depends on multiple pathophysiological, clinical, and epidemiological factors that generally overlap. Both insulin resistance and decreased insulin secretion are considered to be the main causes. The diagnosis and approach to the prediabetic patient are heterogeneous. There is no agreement on the diagnostic criteria to identify prediabetic subjects or the approach to those with insufficient responses to treatment, with respect to regression to normal glycemic values or the prevention of complications. The stratification of prediabetic patients, considering the indicators of impaired fasting glucose, impaired glucose tolerance, or HbA1c, can help to identify the sub-phenotypes of subjects at risk for T2DM. However, considering other associated risk factors, such as impaired lipid profiles, or risk scores, such as the Finnish Diabetes Risk Score, may improve classification. Nevertheless, we still do not have enough information regarding cardiovascular risk reduction. The sub-phenotyping of subjects with prediabetes may provide an opportunity to improve the screening and management of cardiometabolic risk in subjects with prediabetes.

The prognostic effect of prediabetes defined by different criteria in patients with stable coronary artery disease: a prospective cohort study in Asia

AIMS

To evaluate the impact of prediabetes identified by different glycemic thresholds (according to ADA or WHO/IEC criteria) and diagnostic tests (fasting plasma glucose [FPG] or hemoglobin A1c [HbA1c]) on clinical outcomes in patients with stable coronary artery disease (CAD).

METHODS AND RESULTS

In this prospective cohort study, we consecutively enrolled 4088 stable CAD non-diabetic patients with a median follow-up period of 3.2 years. Prediabetes was defined according to ADA criteria as FPG 5.6∼6.9 mmol/L and/or HbA1c 5.7∼6.4%, and WHO/IEC criteria as FPG 6.1∼6.9 mmol/L and/or HbA1c 6.0∼6.4%. The primary endpoint was major adverse cardiovascular event (MACE), including all-cause death, myocardial infarction, or stroke. The prevalence of prediabetes defined according to ADA criteria (67%) was double that of WHO/IEC criteria (34%). Compared with patients with normoglycaemia, those with WHO/IEC-defined prediabetes were significantly associated with higher risk of MACE [adjusted hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.10-2.06], mainly driven by the higher incidence of events in individuals with HbA1c-defined prediabetes. However, this difference was not found in patients with ADA-defined prediabetes and normoglycaemia (adjusted HR 1.17, 95% CI 0.81-1.68). Although FPG was not associated with cardiovascular events, HbA1c improved the risk prediction for MACE in a model of traditional risk factors. Furthermore, the optimal cutoff value of HbA1c for predicting MACE was 5.85%, which was close to the threshold recommended by IEC.

CONCLUSION

This study supports the use of WHO/IEC criteria for the identification of prediabetes in stable CAD patients. Haemoglobin A1c, rather than FPG, should be considered as a useful marker for risk stratification in this population.

REGISTRATION

Not applicable.

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.

DMF scores in patients with diabetes mellitus: A systematic review and meta-analysis of observational studies

OBJECTIVE

The aim of this systematic review(SR) is to comprehensively and critically summarise and synthesise the available scientific evidence from observational studies that use the decayed-missed-filled(DMF) index to determine caries experiences among adult patients with diabetes mellitus  (DM) as compared to individuals without DM(non-DM).

DATA

Indices that present examinations of decayed-filled-surfaces(DFS), decayed-missed-filled-surfaces(DMFS), and decayed-missed-filled-teeth(DMFT) established from observational studies were considered.

SOURCES

MEDLINE-PubMed and Cochrane Central databases were searched through 1 February 2023 to identify studies that evaluate DMF indices for adult patients with DM compared to non-DM. The reference lists of the selected studies were reviewed to identify additional potentially relevant studies.

STUDY SELECTION

All studies were independently screened by two reviewers. Included papers were critically appraised using pre-designed forms, and the risk of bias was assessed. Data as means and standard deviations were extracted. A descriptive data presentation was used for all studies. If quantitative methods were feasible, then a meta-analysis was performed. It was decided 'a priori' to perform a sub-analysis on type of DM(I or II). The quality of the studies was assessed.

RESULTS

Initially 932 studies were found, and screening resulted in 13 eligible observational studies. The total number of subjects included in this SR is 21,220. A descriptive analysis of the comparisons demonstrated that eight studies provided data and demonstrated higher DFS (1/2), DMFS (2/3) and DMFT (5/8). This was confirmed by the meta-analysis difference of means(DiffM), which was 3.01([95%CI:1.47,4.54],p=0.0001) for DMFT and 10.30([95% CI:8.50,12.11],p<0.00001) for DMFS. Subgroup analysis showed that this difference is irrespective to the type of DM(DiffM=3.09;[95%CI:2.09,4.09],p<0.00001).

CONCLUSION

There is moderate certainty for a higher DMF index score in DM patients as compared to those without DM disease.

CLINICAL SIGNIFICANCE

This SR indicates a higher DMF index in DM patients. Oral disease prevention should be the focus of the dental care practitioner in this patient category.

The prediabetes conundrum: striking the balance between risk and resources

The current definition of prediabetes is controversial and subject to continuous debate. Nonetheless, prediabetes is a risk factor for type 2 diabetes, is highly prevalent and is associated with diabetic complications and mortality. Thereby, it has the potential to become a huge strain on healthcare systems in the future, necessitating action from legislators and healthcare providers. But how do we best reduce its associated burden on health? As a compromise between differing opinions in the literature and among the authors of this article, we suggest stratifying individuals with prediabetes according to estimated risk and only offering individual-level preventive interventions to those at high risk. At the same time, we argue to identify those with prediabetes and already established diabetes-related complications and treat them as we would treat individuals with established type 2 diabetes.

Historical review of the diagnosis of prediabetes/intermediate hyperglycemia: Case for the international criteria

In 1997, the ADA recommended an IFG criterion for diagnosing prediabetes/intermediate hyperglycemia of FPG concentrations of 6.1-6.9 mmol/L (110-125 mg/dL). In 2003, they lowered it to 5.6-6.9 mmol/L (100-125 mg/dL) to equalize developing diabetes between IGT and IFG. International organizations accepted the first IFG criterion but not the second. The ADA subsequently recommended HbA1c levels for diagnosing prediabetes/intermediate hyperglycemia of 39-47 mmol/mol (5.7-6.4%) based on a model that utilized the composite risk of developing diabetes and CVD. However, the evidence that the intermediate hyperglycemia that defines prediabetes is independently associated with CVD is weak. Rather, the other risk factors for CVD in the metabolic syndrome are responsible. The WHO opined that prediabetes/intermediate hyperglycemia could not be diagnosed by HbA1c levels but the Canadians and Europeans recommended its diagnosis by values of 42-47 mmol/mol (6.0-6.4%). With the ADA criteria, approximately one-half of people are normal on re-testing, one-third spontaneously revert to normal over time and two-thirds never develop diabetes in their lifetimes. The international criteria for prediabetes/intermediate hyperglycemia increase the risk of developing diabetes and might motivate these individuals to more seriously undertake lifestyle interventions as a preventive measure.

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.

Efficacy of lifestyle intervention in adults with impaired glucose tolerance with and without impaired fasting plasma glucose: A post hoc analysis of Da Qing Diabetes Prevention Outcome Study

AIMS

The extent that pre-diabetic fasting plasma glucose (FPG) levels influence the effectiveness of lifestyle interventions in preventing type 2 diabetes (T2DM) is uncertain. We aimed to determine if the outcome of lifestyle intervention in people with impaired glucose tolerance (IGT) differs in those with normal or impaired FPG levels.

MATERIALS AND METHODS

Data were used from the Da Qing Diabetes Prevention Outcome Study, which was a 30-year follow-up of a 6-year randomized trial of lifestyle intervention in 576 people with IGT. We then conducted a post-hoc analysis to compare the efficacy of intervention to reduce the incidence of T2DM and its complications in those with baseline FPG <100 mg/dL and FPG ≥100 mg/dL.

RESULTS

Lifestyle intervention reduced the cumulative incidence of T2DM by 37%-46% in those with baseline FPG <100 mg/dL and by 47%-51% in those with FPG ≥100 mg/dL. The FPG <100 mg/dL group had a lower cumulative incidence of diabetes and 6.41 years median delay in its onset compared with 2.21 years delay in the FPG ≥100 mg/dL group. In those with FPG <100 mg/dL intervention was associated with at least as great a reduction in cardiovascular disease and all-cause mortality as in the FPG ≥100 mg/dL group.

CONCLUSIONS

Lifestyle intervention reduced the incidence of T2DM in people with IGT regardless of baseline FPG levels, and in those with FPG <100 mg/dL led to a substantial delay in its onset. All persons with IGT, with normal or impaired FPG levels, may benefit from lifestyle intervention to delay its onset and mitigate the incidence of T2DM.

The prevalence and correlates of pre-diabetes in middle- to older-aged Irish adults using three diagnostic methods

BACKGROUND AND OBJECTIVES

Type 2 diabetes is a leading cause of death and disability worldwide and pre-diabetes is a strong predictor of diabetes development. To date, studies estimating the prevalence of pre-diabetes in the Irish population are sparse and conflicting. Monitoring the prevalence of pre-diabetes and a knowledge of associated factors is required to inform policies and to prevent development of type 2 diabetes. Therefore, this research examined the prevalence and correlates of pre-diabetes in a sample of middle- to older-aged Irish adults using three different methods for diagnosis.

MATERIALS AND METHODS

The Mitchelstown Cohort Rescreen (2016/17) was a follow-up, cross-sectional study of the Mitchelstown Cohort Study (2010/11). 1,378 participants were recruited from a random sample of patients attending a single primary care centre. Pre-diabetes was defined using three diagnostic criteria: American Diabetes Association (ADA) glycated haemoglobin A1c (HbA1c) cut-offs between 5.7%-6.4% (39-46 mmol/mol), World Health Organization International Expert Committee (WHO-IEC) HbA1c cut-offs between 6.0%-6.4% (42-46 mmol/mol) and ADA fasting plasma glucose (FPG) cut-offs between 5.6-6.9 mmol/l. Univariate and multivariable logistic regression analyses were used to determine factors associated with pre-diabetes.

RESULTS

The prevalence of pre-diabetes was found to be 43.9% (95% CI: 41.2%─46.5%), 14.5% (95% CI: 12.7%─16.5%) and 15.8% (95% CI: 13.9%─17.8%) according to HbA1c ADA, HbA1c WHO-IEC and FPG ADA definitions, respectively. Depending on diagnostic method, factors associated with pre-diabetes in univariate analyses included sex, age, marital status, health rating, education and poor diet quality. In multivariable analysis, subjects classified by the FPG ADA pre-diabetes criterion displayed the least optimal metabolic profile defined by overweight and obesity (OR = 2.88, 95% CI: 1.53-5.43), hypertension (OR = 2.27, 95% CI: 1.51-3.40) and low high-density lipoprotein cholesterol concentrations (OR = 1.75, 95% CI: 1.07-2.87).

CONCLUSIONS

The discordance between prevalence estimates according to method of diagnosis is concerning. A National Diabetes Prevention Programme is currently being developed in Ireland. Monitoring the prevalence of pre-diabetes over time will be important to assess the effectiveness of this programme. This study will inform national decision-makers on which definition of pre-diabetes to use for monitoring purposes.

Emerging Diabetic Novel Biomarkers of the 21st Century

Diabetes is a growing epidemic with estimated prevalence of infected to reach ~592 million by the year 2035. An effective way to approach is to detect the disease at a very early stage to reduce the complications and improve lifestyle management. Although several traditional biomarkers including glucated hemoglobin, glucated albumin, fructosamine, and 1,5-anhydroglucitol have helped in ease of diagnosis, there is lack of sensitivity and specificity and are inaccurate in certain clinical settings. Thus, search for new and effective biomarkers is a continuous process with an aim of accurate and timely diagnosis. Several novel biomarkers have surged in the present century that are helpful in timely detection of the disease condition. Although it is accepted that a single biomarker will have its inherent limitations, combining several markers will help to identify individuals at high risk of developing prediabetes and eventually its progression to frank diabetes. This review describes the novel biomarkers of the 21st century, both in type 1 and type 2 diabetes mellitus, and their present potential for assessing risk stratification due to insulin resistance that will pave the way for improved clinical outcome.

The risk of hip fractures in individuals over 50 years old with prediabetes and type 2 diabetes - A longitudinal nationwide population-based study

BACKGROUND

The present study aimed to investigate the association between type 2 diabetes mellitus (T2DM) and hip fractures using a large-scale nationwide population-based cohort that is representative of the Republic of Korea. We determined the risks of hip fractures in individuals with prediabetes and T2DM with different diabetes durations, and compared them with the risks of hip fractures in individuals without T2DM.

METHODS

A total of 5,761,785 subjects over 50 years old who underwent the National Health Insurance Service medical checkup in 2009-2010 were included. Subjects were classified into 5 groups based on the diabetes status; Normal, Prediabetes, Newly-diagnosed T2DM, T2DM less than 5 years, and T2DM more than 5 years. They were followed from the date of the medical checkup to the end of 2016. The endpoint was a new development of hip fracture during follow-up. The hazard ratios (HRs) and 95% confidence intervals (CIs) of hip fractures for each group were analyzed using Cox proportional hazard regression models after adjusting for age, sex, smoking, alcohol drinking, regular exercise, body mass index, hypertension, dyslipidemia, and chronic kidney disease.

RESULTS

The HRs of hip fractures were 1 in the Normal group, 1.032 (95% CI: 1.009, 1.056) in the Prediabetes group, 1.168 (95% CI: 1.113, 1.225) in the Newly-diagnosed T2DM2, 1.543 (95% CI: 1.495, 1.592) in the T2DM less than 5 years and 2.105 (95% CI: 2.054, 2.157) in the T2DM more than 5 years. The secular trend of the HRs of hip fractures according to the duration of T2DM was statistically significant (P < .001). Subgroup analyses also showed the same increasing pattern of the HRs of hip fractures according to the duration of T2DM in both sexes and all age groups (50-64 years, 65-74 years, over 75 years).

CONCLUSIONS

In summary, this large-scale, retrospective, longitudinal, nationwide population-based cohort study of 5,761,785 subjects demonstrated that the risks of hip fractures started to increase in prediabetes and was associated linearly with the duration of T2DM. The secular trend of risks of hip fractures according to the duration of T2DM was consistent in both sexes and all age groups.

Evidence and Challenges for Translation and Population Impact of the Diabetes Prevention Program

PURPOSE OF REVIEW

Type 2 diabetes is common, burdensome, and preventable. Landmark trials such as the Diabetes Prevention Program (DPP) demonstrated that resource-intensive lifestyle support interventions resulting in modest weight loss via healthy diet changes and physical activity can lower the rate of diabetes development by 58%. We performed a review of efforts to translate and implement DPP-like programs throughout the USA to identify challenges and opportunities for improvement.

RECENT FINDINGS

For more than a decade, multiple stakeholders have worked to translate evidence-based principles of diabetes prevention to reach 84 million Americans with prediabetes. DPP-like programs have been delivered by over 1500 organizations, reaching almost 300,000 people, but this number represents less than 1% of the target population. Research has uncovered large gaps in efforts to diagnose, raise awareness, and provide access to DPP-like programs for adults with prediabetes, requiring further stakeholder engagement and coordination to resolve. Efforts to address prevailing gaps in diabetes prevention must address distinct and sometimes conflicting priorities and concerns of stakeholders. Our review recommends several areas of further research and action to improve type 2 diabetes prevention on a population scale.

Trends in Self-reported Prediabetes and Metformin Use in the USA: NHANES 2005-2014

BACKGROUND

The American Diabetes Association (ADA) recommends that treatment with metformin be considered for prevention of type 2 diabetes in persons with prediabetes. However, metformin use outside the setting of diagnosed diabetes in US adults is not well characterized.

OBJECTIVE

To examine trends in self-reported prediabetes and treatment with metformin. We also compared characteristics of adults self-reported prediabetes who were vs. were not taking metformin.

DESIGN

Cross-sectional analysis.

PARTICIPANTS

Adults ≥ 20 years of age who participated in the 2005-2014 National Health and Nutrition and Examination Survey (NHANES), n = 28,461.

APPROACH

We characterized trends in self-reported prediabetes and metformin use in this population. We used multiple logistic regression models to identify predictors of metformin use among adults with self-reported prediabetes. All analyses accounted for the weighted complex survey design to generate nationally representative estimates.

KEY RESULTS

The prevalence of self-reported prediabetes increased from 5.1% in 2005-2006 to 7.4% in 2013-2014 (P-for-trend < 0.001). In persons with self-reported prediabetes, metformin use increased, from 2.4 to 8.3% (P-for-trend = 0.013). Adults who were taking metformin were more likely to be obese and to report trying to lose weight in the past year.

CONCLUSIONS

Self-reported prediabetes has increased in the past decade. Metformin use in the setting of prediabetes has also increased but remains relatively uncommon at 8% in adults who self-report prediabetes, despite current clinical recommendations.

Sex and age differences in prevalence and risk factors for prediabetes in Mexican-Americans

AIMS

Over 1/3 of Americans have prediabetes, while 9.4% have type 2 diabetes. The aim of our study was to estimate the prevalence of prediabetes in Mexican Americans, with known 28.2% prevalence of type 2 diabetes, by age and sex and to identify critical socio-demographic and clinical factors associated with prediabetes.

METHODS

Data were collected between 2004 and 2017 from the Cameron County Hispanic Cohort in Texas. Weighted crude and sex- and age- stratified prevalences were calculated. Survey weighted logistic regression analyses were conducted to identify risk factors for prediabetes.

RESULTS

The prevalence of prediabetes (32%) was slightly higher than the alarmingly high rate of type 2 diabetes (28.2%). Hispanic men had the highest overall (37.8%) and highest age stratified prevalence of prediabetes. Males had higher odds of prediabetes than females 1.56 (1.19, 2.06), controlling for the effect of family history of diabetes, age, BMI, and high-density lipoprotein. Family history of diabetes was a strong independent risk factor for prediabetes in all men, and in men and women in the age group 40-64 years. Elevated triglycerides (p = 0.003) was an independent risk factor for men and women in the age group 18-39 years.

CONCLUSIONS

Despite the very high prevalence of type 2 diabetes, prediabetes prevalence among Mexican Americans is only marginally less than national prediabetes rates. This suggests that progression to type 2 diabetes is more rapid and occurs earlier than nationally. Earlier screening and interventions for prediabetes, especially for men, are necessary to slow the transition to diabetes.

Contribution of epicardial and abdominopelvic visceral adipose tissues in Chinese adults with impaired glucose regulation and diabetes

AIMS

To quantify epicardial adipose tissue (EAT) and visceral adipose tissue (VAT) in Chinese adults with impaired glucose regulation (IGR) or diabetes and compare the contributions of EAT and VAT to the occurrence of IGR and diabetes with those of traditional obesity indices.

METHODS

Cardiac and abdominopelvic noncontrast computed tomographic images of 668 individuals were used to measure EAT and VAT volume. Multivariable logistic regression and area under the receiver operating characteristic (ROC) curve were used to illustrate the contributions of these tissues.

RESULTS

Patients with IGR or diabetes had larger EAT and VAT volumes than did the controls, and the VAT volume was significantly different between the IGR and diabetic groups. In multivariable models, higher EAT or VAT volume was positively associated with the presence of IGR and diabetes. After adjusting further for body mass index (BMI) and waist-to-hip ratio (WHR), a higher EAT volume was still positively associated with IGR (odds ratio (OR) = 1.46; 95% confidence interval (CI), 1.04-2.03), and a higher VAT volume was positively associated with IGR (OR = 1.86; 95% CI, 1.15-3.02) and diabetes (OR = 1.86; 95% CI, 1.16-2.99). The areas under the curve (AUCs) of the association of EAT (AUC = 0.751; 95% CI, 0.712-0.789) and VAT (AUC = 0.752; 95% CI, 0.713-0.792) with dysglycemia (IGR + diabetes) were significantly larger than those of the traditional obesity indices (all P < 0.05).

CONCLUSIONS

High EAT or VAT volume is positively associated with IGR and diabetes in Chinese adults. With a given WHR and BMI, such an association still exists to some extent. The correlation may be stronger than those of the traditional obesity indices.

Prediabetes defined by HbA1c and by fasting glucose: differences in risk factors and prevalence

AIMS

To investigate, in a sample of nondiabetic adults from a Spanish community, the differences between prediabetes as defined by HbA_1c ("H-prediabetes") and by fasting plasma glucose (FPG) ("F-prediabetes") in regard to prevalence and the influence of potential risk factors, adjusting the latter for confounders.

METHODS

A total of 1328 nondiabetic participants aged ≥ 18 years were classified as normoglycemic, H-prediabetic [HbA_1c 5.7-6.4% (39-47 mmol/mol)] or F-prediabetic (FPG 5.6-6.9 mmol/L). Multivariable analyses were used to compare the impacts of risk factors on the prevalence of H-prediabetes, F-prediabetes and their conjunctive and disjunctive combinations ("HaF-prediabetes" and "HoF-prediabetes," respectively).

RESULTS

Some 29.9% of participants were HoF-prediabetic, 21.7% H-prediabetic, 16.3% F-prediabetic and only 8.1% HaF-prediabetic. Whatever the definition of prediabetes, increasing age, fasting insulin and LDL cholesterol were each a risk factor after adjustment for all other variables. Increasing BMI and decreasing mean corpuscular hemoglobin (MCH) were additional risk factors for H-prediabetes; male sex and increasing uric acid for F-prediabetes and increasing BMI for HaF-prediabetes. The participants satisfying the compound condition "hypertension or hyperlipidemia or obesity or hyperuricemia" (59.9% of the whole study group) included 83.1% of all subjects with HoF-prediabetes.

CONCLUSIONS

In this population, the most sensitive risk factor for detection of prediabetes was age, followed by fasting insulin, LDL cholesterol, BMI, MCH, male sex and uric acid, with differences depending on the definition of prediabetes. MCH, an indirect measure of erythrocyte survival, significantly influences the prevalence of HbA_1c-defined prediabetes. This study suggests that screening of individuals with selected risk factors may identify a high proportion of prediabetic persons.

Prevalence of prediabetes and type 2 diabetes in two non-random populations aged 44-77 years in the Faroe Islands

AIMS

The prevalence of type 2 diabetes is increasing worldwide but little known about the status in the Faroe Islands. The aim was therefore to determine the prevalence of type 2 diabetes mellitus and prediabetes in two non-random populations aged 44-77 years.

METHODS

This cross-sectional survey was conducted between 2011 and 2012 and included two sub-populations, namely 518 Septuagenarians aged 74-77 years (84% of the invited) and 401 Mark aged 44-73 years (87% of the invited). Subjects were screened for glycosylated haemoglobin, type A1c, non-fasting random plasma glucose, fasting plasma glucose followed by an oral glucose tolerance test. The screening was based on a diagnostic algorithm that included screening, diagnostic and confirmatory steps.

RESULTS

Each group was analysed separately. In the Septuagenarian group 20.4% had type 2 diabetes, with 5.2% being newly detected and a total of 59% had prediabetes. In the Mark group 4.1% had diabetes, with 2.1% being newly detected and 22.3% had prediabetes. Diabetes increased with age and was significantly more prevalent among men. Women had lower mean fasting plasma glucose concentrations and men had lower values for 2-hours plasma glucose. Significant predictors associated with diabetes mellitus included obesity (BMI ≥ 30, abnormal waist/hip ratio and vegetable consumption.

CONCLUSIONS

Among the Faroese populations studied, the prevalence of type 2 diabetes increased with age and was more prevalent among men. The detected prevalence was comparable to other Nordic countries for all age-groups.

Prediction of type 2 diabetes mellitus using noninvasive MRI quantitation of visceral abdominal adiposity tissue volume

Background

The correlation between visceral adipose tissue volume (VATV), hepatic proton-density fat fraction (PDFF), and pancreatic PDFF has been previously studied to predict the presence of type 2 diabetes mellitus (T2DM). This study investigated VATV quantitation in patients with T2DM, prediabetes, and normal glucose tolerance (NGT) using MRI to assess the roles of VATV, hepatic, and pancreatic PDFF in predicting the presence of T2DM.

Methods

Forty-eight patients with a new clinical diagnosis of T2DM (n=15), prediabetes (n=17), or NGT (n=16) were included and underwent abdominal magnetic resonance imaging (MRI) scanning with the iterative decomposition of water and fat with echo asymmetry and least square estimation image quantification (IDEAL-IQ) sequencing. VATV was obtained at the level of the 2^nd and 3^rd lumbar vertebral bodies (VATV L2 and VATV L3) where the sum of VATV L2 and VATV L3 (total VATV) were computed, respectively. Also, pancreatic and hepatic fat content was quantified by measuring the PDFF. The receiver operating characteristic (ROC) curve and binary logistics regression model analysis were employed to evaluate their ability to predict the presence of T2DM.

Results

The VATV L2, VATV L3, and total VATV values of the T2DM group were significantly higher than the prediabetes and NGT groups (P<0.05). There was no statistically significant difference between the values of VATV L2, VATV L3, and total VATV between the prediabetes and NGT groups (P>0.05). The ROC curve showed the areas under the curve for VATV L2, VATV L3, total VATV, hepatic PDFF, and pancreatic PDFF were 0.76, 0.80, 0.80, 0.79, and 0.75, respectively, in predicting the presence of T2DM (P<0.01). The ROC curves of VATV L2, VATV L3, total VATV, hepatic PDFF, and pancreatic PDFF failed to predict the presence of prediabetes and NGT (P>0.05). The binary logistics regression model analysis revealed that only VATV L3 was independently associated with the incidence of T2DM (P=0.01 and OR =1.01). The sensitivity, specificity, and total accuracy were 80.00%, 88.20%, and 84.40%, respectively.

Conclusions

Compared with hepatic PDFF, pancreatic PDFF, VAVT L2, and total VATV, VAVT L3 was the better predictor of T2DM.

Issues in Defining the Burden of Prediabetes Globally

PURPOSE OF REVIEW

Using a global perspective, this review collates evidence on the heterogeneity of prediabetes definitions and diagnostic methods, their clinical and public health implications, and discusses possible options for improvement.

RECENT FINDINGS

Our review notes that the concept of prediabetes is increasingly recognized worldwide, but against a background of non-uniform definition and diagnostic criteria. This results in widely varying burden estimation. Current evidence shows a variety of prediabetes phenotypes. This reflects biological and diagnostic heterogeneity, resulting from the use of different tests (glucose or HbA_1C) and thresholds to define prediabetes. The biological and diagnostic variabilities have implications for the characterization of the burden of prediabetes, natural history, prognosis, screening, implementation of lifestyle or drug interventions to mitigate related health risks, and monitoring of the effects of such interventions.

Continuous glucose monitoring is more sensitive than HbA1c and fasting glucose in detecting dysglycaemia in a Spanish population without diabetes

AIMS

To investigate whether continuous glucose monitoring (CGM) reveals patterns of glycaemic behaviour, the detection of which might improve early diagnosis of dysglycaemia.

METHODS

A total 1521 complete days of valid CGM data were recorded under real-life conditions from a healthy sample of a Spanish community, as were matching FPG and HbA1_C data. No participant was pregnant, had a history of kidney or liver disease, or was taking drugs known to affect glycaemia.

RESULTS

CGM and fingerstick measurements showed a mean relative absolute difference of 6.9 ± 2.2%. All subjects were normoglycaemic according to FPG and HbA_1C except 21% who were prediabetic. The normoglycaemic subjects had a 24-hour mean blood glucose concentration (MBG) of 5.7 ± 0.4 mmol/L, spending a median of 97% of their time within the target range (3.9-7.8 mmol/L). 73% of them experienced episodes with blood glucose levels above the threshold for impaired glucose tolerance, and 5% levels above the threshold for diabetes. These normoglycaemic participants with episodes of high glycaemia had glycaemic variabilities similar to those of prediabetic subjects with episodes of similar intensity or combined duration.

CONCLUSIONS

CGM is a better indicator of possible early dysglycaemia than either FPG or HbA1c.

Prevalence of type 2 diabetes and prediabetes in the Faroe Islands

AIMS

To determine the prevalence of type 2 diabetes mellitus and prediabetes among the population aged 40-74 years in the Faroe Islands.

METHODS

This population-based cross-sectional survey, conducted between 2011 and 2012, invited 2186 randomly selected individuals (corresponding to 11.1% of the entire population aged 40-74 years). Subjects were screened using finger capillary blood for glycosylated hemoglobin, type A1c, non-fasting random plasma glucose, fasting plasma glucose followed by oral glucose tolerance test. The test was based on an algorithm that accounts for screening, diagnostic and confirmatory steps. Anthropometric measures and a questionnaire including medical history, medication, hereditary conditions, and food intake were included.

RESULTS

The study included 1772 participants. Of the 1772, 169 (9.5%) had type 2 diabetes mellitus (3.0% of which were diagnosed upon study inclusion), thus 31.4% of subjects with diabetes were undiagnosed at the time of examination. A total of 271 (15.3%) had prediabetes. Diabetes was more prevalent among men, significantly from age ≥60 years. Women had lower mean fasting plasma glucose concentrations and men had lower values for 2-h plasma glucose. Predictors associated with diabetes mellitus included obesity (BMI ≥ 30), abnormal waist/hip ratio, history of hypertension or cardiovascular attack and family history of diabetes mellitus and leisure activity.

CONCLUSIONS

The prevalences of diabetes and prediabetes increased with age and were more frequent among men. The detected prevalence in the Faroe Islands was slightly higher than other Nordic countries.

Do Words Matter? Health Care Providers' Use of the Term Prediabetes

Communication of risk is not solely the transfer of information; it is an interaction and exchange of ideas between concerned individuals. Health care provider communication about type 2 diabetes risk status may influence individual participation in behaviours that prevent or delay the disease, which is concerning from a public health perspective. The term prediabetes is used to convey risk status and little is known about how health care providers view or use the term. In this article, we describe health care provider use and perceptions of the term prediabetes drawing on data from a survey conducted between August and November 2011 of 15 health care providers practicing in Southeast Wyoming and Northern Colorado USA. We used a grounded theory research design to guide data collection and analysis and in the interviews invited providers to describe their use and perception of the term prediabetes. We found that providers use of the term 'prediabetes' depended on their view of the term's meaning (such as, whether patients were likely to understand or be confused by it) and impact (in terms of motivating patients to mitigate risk). We found there were differences in providers' perceptions of the negative and positive associations of the term and this influenced whether or not they used it. These findings are not surprising given the lack of consensus over definitions and diagnosis criteria for prediabetes. Given this this lack of agreement, there are difficulties about the use of the term prediabetes and its use should take place within effective risk communication. Health care providers must consider essential aspects of risk communication in order to enable individuals at risk of type 2 diabetes to mitigate the risk and by doing so reduce incidence and prevalence rates of the disease.

Prevalence, awareness, treatment and control of diabetes and impaired fasting glucose in the Southern Cone of Latin America

AIMS

To determine the prevalence, treatment and control of diabetes mellitus (DM) and impaired fasting glucose (IFG) as well as associated factors in the adult population of four cities of the Southern Cone of Latin America (SCLA).

METHODS

This is a cross-sectional population-based study that included 7407 adults between 35 and 74 years old in four cities of the SCLA: Temuco (Chile), Marcos Paz and Bariloche (Argentina), and Pando-Barros Blancos (Uruguay). DM was defined as fasting plasma glucose ≥126 mg/dL or self-reported history of diabetes. Awareness, treatment, and control of DM were defined as subjects self-reporting a DM previous diagnosis, the use of a prescription medication or nonpharmacological intervention for DM, and fasting plasma glucose <126 mg/dl, respectively.

RESULTS

Prevalence of DM varied among cities, between 8.4% in Bariloche and 14.3% in Temuco. Prevalence of IFG varied at different sites, from 3.5% in Barros Blancos to 6.8% in Marcos Paz. Of the total number of people with diabetes, 20% were newly diagnosed at the time of the study. Overall, 79.8% of patients with diabetes were aware of their condition. The treatment and control rate were 58.8% and 46.2%, respectively. Older age, family history of diabetes, lower educational attainment, overweight, obesity, central obesity, low physical activity, hypertension, hypercholesterolemia and hypertriglyceridemia were all significantly associated with an increased risk of diabetes.

CONCLUSIONS

The prevalence of DM and IFG in the adult population of the SCLA is high and varies among cities. These conditions represent a public health challenge since the rates of awareness, treatment, and control are still low.

Pancreatic fat content by magnetic resonance imaging in subjects with prediabetes, diabetes, and controls from a general population without cardiovascular disease

Background/Objective

Despite the relevance of pancreatic fat content in the development of metabolic diseases, its association with impaired glucose metabolism, diabetes, and other adipose tissue compartments remains unclear. Thus, we determined differences in pancreatic fat content by magnetic resonance imaging (MRI) between subjects with prediabetes, diabetes, and normal controls in a cohort from the general population.

Methods

Subjects without history of cardiovascular disease with established diabetes or prediabetes as well as normal controls were included and underwent whole-body MRI on a 3T scanner. Pancreatic fat content was quantified by measuring the proton-density fat fraction (PDFF_panc) using a 3D multi-echo GRE sequence (increment: 1.23 ms, 6 echoes) by placing ROIs in the pancreatic head, body, and tail by independent readers. In addition, hepatic fat content as well as abdominal subcutaneous and visceral adipose tissue (SAT and VAT) were measured by multi-echo GRE and 3D 2-point volume-interpolated DIXON MRI, respectively. Univariate and multivariate analyses were employed to determine associations.

Results

A total of 385 subjects were included in the analysis (median age: 57 years, 58.2% males), of them 53 were classified as subjects with diabetes, 95 as prediabetes, and 237 as controls (13.8%, 24.7%, and 61.6%; respectively). The median PDFF_panc was 5.2% [IQR 3.3–9.4], and significantly higher in subjects with prediabetes and diabetes as compared to controls (PDFF_panc: 6.2% [IQR: 3.5–12] vs. 8.6% [IQR: 4.3–17.5] vs. 4.9% [3.1–7.4], p<0.001, respectively). After adjusting for age, gender and BMI the association was attenuated (all p>0.12). While in univariate analysis BMI, PDFF_hepatic, SAT and VAT were associated with PDFF_panc (all p<0.05), only VAT predicted PDFF_panc independently (β: 0.02, 95%-confidence interval: 0.01–0.04, p<0.001).

Conclusion

While pancreatic fat content differs significantly between subjects with prediabetes, diabetes and controls, this association may be confounded by age, gender, and the amount of VAT in this cross-sectional study.

Medical Care Expenditures for Individuals with Prediabetes: The Potential Cost Savings in Reducing the Risk of Developing Diabetes

The United States has 86 million adults with prediabetes. Individuals with prediabetes can prevent or delay the development of type 2 diabetes through lifestyle modifications such as participation in the National Diabetes Prevention Program (DPP), thereby mitigating the medical and economic burdens associated with diabetes. A cohort analysis of a commercially insured population was conducted using individual-level claims data from Truven Health MarketScan^® Lab Database to identify adults with prediabetes, track whether they develop diabetes, and compare medical expenditures for those who are newly diagnosed with diabetes to those who are not. This study then illustrates how reducing the risk of developing diabetes by participation in an evidence-based lifestyle change program could yield both positive net savings on medical care expenditures and return on investment (ROI). Annual expenditures are found to be nearly one third higher for those who develop diabetes in subsequent years relative to those who do not transition from prediabetes to diabetes, with an average difference of $2671 per year. At that cost differential, the 3-year ROI for a National DPP is estimated to be as high as 42%. The results show the importance and economic benefits of participation in lifestyle intervention programs to prevent or delay the onset of type 2 diabetes.

Novel biomarkers for prediabetes, diabetes, and associated complications

The number of individuals with prediabetes is expected to grow substantially and estimated to globally affect 482 million people by 2040. Therefore, effective methods for diagnosing prediabetes will be required to reduce the risk of progressing to diabetes and its complications. The current biomarkers, glycated hemoglobin (HbA1c), fructosamine, and glycated albumin have limitations including moderate sensitivity and specificity and are inaccurate in certain clinical conditions. Therefore, identification of additional biomarkers is being explored recognizing that any single biomarker will also likely have inherent limitations. Therefore, combining several biomarkers may more precisely identify those at high risk for developing prediabetes and subsequent progression to diabetes. This review describes recently identified biomarkers and their potential utility for addressing the burgeoning epidemic of dysglycemic disorders.

High Prevalence of Diabetes and Prediabetes and Their Coexistence with Cardiovascular Risk Factors in a Hispanic Community

This study examined the prevalence and association of diabetes mellitus (DM) and prediabetes with cardiovascular risk factors among Puerto Ricans adults. Data from a household survey of 857 adults aged 21-79 years who underwent interviews, physical exams, and blood draws were analyzed. Prevalence of total DM and prediabetes was estimated using American Diabetes Association diagnostic criteria of fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c). Poisson regression models were used to estimate the prevalence ratio for each cardiovascular risk factor under study. Age-standardized prevalence of total DM and prediabetes, detected by FPG and/or HbA1c, was 25.5 and 47.4 %, respectively. Compared with participants with normoglycemia, those with previously diagnosed DM, undiagnosed DM, and prediabetes had more adverse cardiovascular risk factor profiles, characterized by a higher prevalence of general and abdominal obesity, hypertension, low HDL cholesterol, elevated LDL cholesterol, elevated triglycerides, and elevated plasminogen activator inhibitor 1 (p < 0.05). The high prevalence of DM and prediabetes calls for public health actions to plan and implement lifestyle interventions to prevent or delay the onset of DM and cardiovascular disease.

Nutrition facts panel use is associated with higher diet quality and lower glycated hemoglobin concentrations in US adults with undiagnosed prediabetes

BACKGROUND

The majority of US consumers use the nutrition facts panel (NFP) or health claims for food selections. Although previous studies have consistently reported positive impacts of NFP use on dietary intake, evidence regarding the effect of the use of health claims, either alone or in combination with the NFP, on diet quality and health outcomes is scarce.

OBJECTIVES

Our primary objective was to test for associations of the use of food labels (the NFP or health claims) with overall diet quality in individuals with prediabetes. In addition, we examined the association between food label use and glycated hemoglobin (HbA1c) concentrations.

DESIGN

We conducted a weighted linear regression, which was appropriate for a complex sampling survey, with the use of cross-sectional data from 2654 US adults with undiagnosed prediabetes who participated in the 2005-2010 NHANES cycles. The following 4 categories of food label (NFP or health claims) use were identified: 1) both labels, 2) health claims only, 3) neither label, and 4) the NFP only. Healthy Eating Index-2010 score, which we used to assess diet quality, was calculated from two 24-h recalls. Blood samples for analyzing HbA1c concentrations (glycemic control) were collected in the mobile examination center.

RESULTS

The overall diet quality scores for the use of both labels [b: -2.76 (95% CI: -5.04, -0.48); P = 0.019], of health claims only [b: -3.46 (-6.64, -0.28); P = 0.033], and of neither label [b: -4.01 (-5.75, -2.28); P < 0.001] were lower than those of NFP-only users. Moreover, HbA1c concentrations of users of both labels [b: 0.09% (95% CI: 0.03%, 0.16%); P = 0.008] and health claims only [b: 0.13% (95% CI: 0.02%, 0.25%); P = 0.021] were higher than those of NFP-only users.

CONCLUSIONS

In participants with undiagnosed prediabetes, the use of health claims alone, of both labels, or of neither label (compared with the use of the NFP only) was associated with poorer diet quality. In addition, users of neither label and users of both labels had poorer glycemic control. Further studies are needed to understand why the use of health claims may not be health promoting in this high-risk population.

PERFORMANCE OF A1C VERSUS OGTT FOR THE DIAGNOSIS OF PREDIABETES IN A COMMUNITY-BASED SCREENING

OBJECTIVE

Reliable identification of individuals at risk for developing diabetes is critical to instituting preventative strategies. Studies suggest that the accuracy of using hemoglobin A1c as a sole diagnostic criterion for diabetes may be variable across different ethnic groups. We postulate that there will be lack of concordance between A1c and the oral glucose tolerance test (OGTT) for diagnosing prediabetes across Hispanic and non-Hispanic white (NHW) populations.

METHODS

A total of 218 asymptomatic adults at risk for type 2 diabetes (T2D) were assessed with A1c and OGTT for the diagnosis of prediabetes. Glucose homeostasis status was assigned as no diabetes (A1c <5.7% [39 mmol/mol]), prediabetes (A1c 5.7 to 6.4% [46 mmol/mol]), and T2D (A1c >6.4% [46 mmol/mol]). Inclusion criteria were age >18 years and at least one of the following: a family history of diabetes, a history of gestational diabetes, Hispanic ethnicity, non-Caucasian race, or obesity. Subjects received a fasting 75-g OGTT and A1c on the same day. Bowker's test of symmetry was employed to determine agreement between the tests.

RESULTS

Data from 99 Hispanic patients and 79 NHW patients were analyzed. There was no concordance between A1c and OGTT for Hispanic (P = .002) or NHW individuals (P = .003) with prediabetes.

CONCLUSION

A1c is discordant with OGTT among Hispanic and NHW subjects for the diagnosis of prediabetes. Sole use of A1c to designate glycemic status will result in a greater prevalence of prediabetes among Hispanic and NHW New Mexicans.

ABBREVIATIONS

A1c = hemoglobin A1c BMI = body mass index CDC = Centers for Disease Control CI = confidence interval FPG = fasting plasma glucose NHW = non-Hispanic white OGTT = oral glucose tolerance test T2D = type 2 diabetes WHO = World Health Organization.

Diabetes mellitus statistics on prevalence and mortality: facts and fallacies

Diabetes mellitus is one of the most important public health challenges of the twenty-first century. Until the past decade, it has been seriously underrated as a global health threat. Major gaps exist in efforts to comprehend the burden nationally and globally, especially in developing nations, due to a lack of accurate data for monitoring and surveillance. Early attempts to obtain accurate data, discussed in this article, seem to have been cast aside so, at present, these needs remain unmet. Existing international efforts to assemble information fall far short of requirements. Current estimates are imprecise, only providing a rough picture, and probably underestimate the disease burden. The methodologies that are currently used, and that are discussed in this Perspectives article, are inadequate for providing a complete and accurate assessment of the prevalence of diabetes mellitus. International consensus on uniform standards and criteria for reporting national data on diabetes mellitus prevalence as well as for common complications of diabetes mellitus and mortality need to be developed.

Incidence Rate of Prediabetes Progression to Diabetes: Modeling an Optimum Target Group for Intervention

Thirty-seven percent of US adults have prediabetes. Various interventions can delay diabetes progression; however, the optimum target group for risk reduction is uncertain. This study estimated rate of progression to diabetes at 1 and 5 years among a cohort of patients from 3 primary care clinics and modeled the potential magnitude in diabetes incidence risk reduction of an intervention program among specific subgroups. Records of 106,821 empaneled patients in 2005 were reviewed. Generalized population attributable risk (PAR) statistics were calculated to estimate the impact of reducing fasting blood glucose on diabetes progression. Multiple intervention effects (varying levels of glucose reduction along with multiple adherence rates) were examined for those with baseline glucose from 110 to 119 mg/dL and ≥120 mg/dL. Ten percent of patients (n = 10,796) met criteria for prediabetes. The 1- and 5-year diabetes incidence rate was 38.6 and 40.24 per 1000 person-years, respectively. Age and obesity were independent predictors of increased progression rate. The generalized PAR for a 10-point reduction in the 110-119 mg/dL subgroup with 25% adherence was 7.6%. The generalized PAR for similar percent reduction and adherence level in patients with baseline glucose of ≥120 mg/dL was only 3.0%. Rate of progression to diabetes increased over time and with associated independent risk factors. Greater risk reduction in diabetes progression within the target population can be achieved when the intervention is successful in those with baseline glucose of 110-119 mg/dL. Modeling an optimum target group for a diabetes prevention intervention offers a novel and useful guide to planning and allocating resources in population health management.

Food Insecurity and Diabetes in Developed Societies

Food insecurity is an important issue in public health even in developed societies, particularly for vulnerable populations. Food insecurity refers to the uncertain or limited access to adequate and safe foods. Emerging evidence shows an association between food insecurity, type 2 diabetes risk factors, and management of type 1 and type 2 diabetes. A review of the current literature describing the association between food insecurity and diabetes reveals possible mechanisms and pathophysiologic pathways. There is less evidence for effective interventions, and much of the current literature is limited to cross-sectional studies. Future work should evaluate longitudinal associations and ways to help vulnerable patients with diabetes access adequate food for effective diabetes management.

"Prediabetes": Are There Problems With This Label? Yes, the Label Creates Further Problems!

The category of "prediabetes" defined by the American Diabetes Association comprises a range of intermediate hyperglycemia based on fasting or 2-h postload glucose or on HbA1c Over the recent past, the "cut points" identifying this stage have changed, i.e., a lower fasting glucose level is used. On one hand, it can be argued that the change to a lower cut point identifies a group of individuals still at higher risk and provides heightened awareness for a condition associated with higher risk for cardiovascular disease. In addition, identification of individuals at this stage may represent a chance of earlier intervention in the disease. However, the argument against this definition of "prediabetes" is that it disguises the differences in the three subcategories and creates problems in interpreting observations on interventions and outcomes. In addition, it can be argued that the enormous numbers of people identified with the criteria far exceeds the capacity of health care systems to respond through individual care, particularly without evidence that interventions benefit any category other than impaired glucose tolerance. Thus, there does not appear to be consensus on the definition using the cut points identified. Controversy also remains as to whether there are glycemic metrics beyond HbA1c that can be used in addition to HbA1c to help assess risk of an individual developing diabetes complications. Given the current controversy, a Point-Counterpoint debate on this issue is provided herein. In the point narrative below, Dr. Yudkin provides his argument that there are significant problems with this label. In the counterpoint narrative that follows Dr. Yudkin's contribution, Dr. Cefalu argues that the cut points are appropriate and do provide useful and important information in trying to reduce the future burden of diabetes.-William T. CefaluEditor in Chief, Diabetes Care.

Risk of progression to diabetes from prediabetes defined by HbA1c or fasting plasma glucose criteria in Koreans

AIMS

To examine the abilities of HbA1c and fasting plasma glucose (FPG) criteria predicting 5-year progression rate to diabetes in Korean adults with prediabetes.

METHODS

Participants included 17,971 Koreans (aged 20-79years) who underwent routine medical check-ups at a mean interval of 5.2years (3.1-6.7years). Prediabetes was defined as FPG 5.6-6.9mmol/l or HbA1c 5.7-6.4% (39-46mmol/mol). Incident diabetes was defined as FPG⩾7.0mmol/l, HbA1c⩾6.5% (48mmol/mol), or initiation of antidiabetic medications.

RESULTS

At baseline, the prevalence of prediabetes was 30.6% (n=5495) by FPG and 20.4% (n=3664) by HbA1c criteria. The 5-year progression rate to diabetes was significantly higher in prediabetes identified by HbA1c than by FPG tests (14.7% vs. 10.4%, P<0.001). Of individuals diagnosed with prediabetes by only one test, those by HbA1c alone had a higher risk of progression to diabetes than those diagnosed by FPG alone (6.0% vs. 3.9%, P<0.001). Receiver operating characteristic curve analysis showed that area under the curve was greater for HbA1c (0.855, 95% CI 0.840-0.870) than for FPG (0.830, 0.813-0.846) (P=0.016). After adjustment for conventional risk factors, the odds ratio (OR) of developing diabetes was higher in participants with prediabetes identified by HbA1c (OR 9.91, 8.24-11.9) than by FPG (OR 7.29, 5.97-8.89) (P=0.026).

CONCLUSIONS

Although fewer individuals with prediabetes were identified by HbA1c than by FPG criteria, the ability to predict progression to diabetes was stronger for HbA1c than for FPG in Koreans.

Total Bilirubin Levels Predict Subclinical Atherosclerosis in Patients With Prediabetes

Bilirubin may have important antiatherosclerotic effects. Prediabetes (PD), the intermediate stage before diabetes mellitus, is associated with increased cardiovascular morbidity and mortality. We evaluated the relationship between serum bilirubin levels and carotid intima-media thickness (cIMT), as a surrogate marker of subclinical atherosclerosis, in patients with PD. We enrolled 170 consecutive patients with PD. The patients underwent ultrasonography to evaluate cIMT. The patients were divided into groups according to cIMT values (<0.9 vs ≥0.9 mm). The patients with cIMT ≥ 0.9 mm had significantly higher diastolic blood pressure, neutrophil-lymphocyte ratio (NLR), and glycated hemoglobin values compared with patients having cIMT < 0.9 mm, whereas total and direct bilirubin values were significantly lower in this group. Multivariate regression analyses revealed NLR and total bilirubin as the independent predictors of subclinical atherosclerosis. The present study demonstrated that NLR and lower total bilirubin levels were independent predictors of subclinical atherosclerosis in patients with PD. Simple measures such as NRL and total bilirubin may provide predictive information regarding the risk of cardiovascular disease in patients with PD.

Update and Next Steps for Real-World Translation of Interventions for Type 2 Diabetes Prevention: Reflections From a Diabetes Care Editors' Expert Forum

The International Diabetes Federation estimates that 415 million adults worldwide now have diabetes and 318 million have impaired glucose tolerance. These numbers are expected to increase to 642 million and 482 million, respectively, by 2040. This burgeoning pandemic places an enormous burden on countries worldwide, particularly resource-poor regions. Numerous landmark trials evaluating both intensive lifestyle modification and pharmacological interventions have persuasively demonstrated that type 2 diabetes can be prevented or its onset can be delayed in high-risk individuals with impaired glucose tolerance. However, key challenges remain, including how to scale up such approaches for widespread translation and implementation, how to select appropriately from various interventions and tailor them for different populations and settings, and how to ensure that preventive interventions yield clinically meaningful, cost-effective outcomes. In June 2015, a Diabetes Care Editors' Expert Forum convened to discuss these issues. This article, an outgrowth of the forum, begins with a summary of seminal prevention trials, followed by a discussion of considerations for selecting appropriate populations for intervention and the clinical implications of the various diagnostic criteria for prediabetes. The authors outline knowledge gaps in need of elucidation and explore a possible new avenue for securing regulatory approval of a prevention-related indication for metformin, as well as specific considerations for future pharmacological interventions to delay the onset of type 2 diabetes. They conclude with descriptions of some innovative, pragmatic translational initiatives already under way around the world.

Diabetes and fracture risk in older U.S. adults

OBJECTIVE

We examined the diabetes-fracture relationship by race/ethnicity, including the link between pre-diabetes and fracture.

RESEARCH DESIGN AND METHODS

We used Medicare- and mortality-linked data for respondents aged 65years and older from the third National Health and Nutrition Examination Survey (NHANES III) and NHANES 1999-2004 for three race/ethnic groups: non-Hispanic whites (NHW), non-Hispanic blacks (NHB), and Mexican Americans (MA). Diabetes was defined as diagnosed diabetes (self-reported) and diabetes status: diagnosed and undiagnosed diabetes (positive diagnosis or hemoglobin A1c (A1C)≥6.5%); pre-diabetes (no diagnosis and A1C between 5.7% and 6.4%); and no diabetes (no diagnosis and A1C<5.7%). Non-skull fractures (n=750) were defined using published algorithms. Hazards ratios (HRs) were calculated using Cox proportional hazards models.

RESULTS

The diabetes-fracture relationship differed significantly by race/ethnicity (pinteraction<0.05). Compared to those without diagnosed diabetes, the HRs for those with diagnosed diabetes were 2.37 (95% CI 1.49-3.75), 1.87 (95% CI 1.02-3.40), and 1.22 (95% CI 0.93-1.61) for MA, NHB, and NHW, respectively, after adjusting for significant confounders. HRs for diagnosed and undiagnosed diabetes were similar to those for diagnosed diabetes alone. Pre-diabetes was not significantly related to fracture risk, however. Compared to those without diabetes, adjusted HRs for those with pre-diabetes were 1.42 (95% CI 0.72-2.81), and 1.20 (95% CI 0.96-1.51) for MA and NHW, respectively. There were insufficient fracture cases to examine detailed diabetes status in NHB.

CONCLUSIONS

The diabetes-fracture relationship was stronger in MA and NHB. Pre-diabetes was not significantly associated with higher fracture risk, however.

Cardiometabolic Risk Profiles in Patients With Impaired Fasting Glucose and/or Hemoglobin A1c 5.7% to 6.4%: Evidence for a Gradient According to Diagnostic Criteria: The PREDAPS Study

It has been suggested that the early detection of individuals with prediabetes can help prevent cardiovascular diseases. The purpose of the current study was to examine the cardiometabolic risk profile in patients with prediabetes according to fasting plasma glucose (FPG) and/or hemoglobin A1c (HbA1c) criteria.Cross-sectional analysis from the 2022 patients in the Cohort study in Primary Health Care on the Evolution of Patients with Prediabetes (PREDAPS Study) was developed. Four glycemic status groups were defined based on American Diabetes Association criteria. Information about cardiovascular risk factors-body mass index, waist circumference, blood pressure, cholesterol, triglycerides, uric acid, gamma-glutamyltransferase, glomerular filtration-and metabolic syndrome components were analyzed. Mean values of clinical and biochemical characteristics and frequencies of metabolic syndrome were estimated adjusting by age, sex, educational level, and family history of diabetes.A linear trend (P < 0.001) was observed in most of the cardiovascular risk factors and in all components of metabolic syndrome. Normoglycemic individuals had the best values, individuals with both criteria of prediabetes had the worst, and individuals with only one-HbA1c or FPG-criterion had an intermediate position. Metabolic syndrome was present in 15.0% (95% confidence interval: 12.6-17.4), 59.5% (54.0-64.9), 62.0% (56.0-68.0), and 76.2% (72.8-79.6) of individuals classified in normoglycemia, isolated HbA1c, isolated FPG, and both criteria groups, respectively.In conclusion, individuals with prediabetes, especially those with both criteria, have worse cardiometabolic risk profile than normoglycemic individuals. These results suggest the need to use both criteria in the clinical practice to identify those individuals with the highest cardiovascular risk, in order to offer them special attention with intensive lifestyle intervention programs.

Incidence of type 2 diabetes and associated factors in the adult population of the Community of Madrid. PREDIMERC cohort

OBJECTIVES

Determine the incidence and risk factors of type2 diabetes in the adult population of Madrid (Spain) and compare the predictive models of type2 diabetes based on the prediabetes criteria of the American Diabetes Association (ADA) and the World Health Organisation (WHO).

MATERIAL AND METHODS

A prospective study was conducted on a population cohort composed of 2048 individuals between 30 and 74years of age with no diabetes. At the start of the study, an epidemiological survey was performed, and baseline glycaemia, HbA1c, body mass index and waist circumference were measured. A follow-up of 6.4years was conducted. New cases of type2 diabetes were identified using the electronic primary care medical history.

RESULTS

The incidence of type2 diabetes was 3.5 cases/1000 person-years. In the multivariate analysis, the variables that were associated with the onset of type2 diabetes were age, family history of diabetes, baseline glycaemia (100-125mg/dL), HbA1c (5.7-6.4%) and waist circumference (≥94cm for men and ≥80cm for women). Of these, the most significantly associated variables were baseline glycaemia and HbA1c. The ADA and WHO criteria for defining prediabetes had the same predictive capacity.

CONCLUSION

The incidence of type2 diabetes measured in Madrid was lower than that found in other population studies, with the glucometabolic state the main factor associated with progression to type2 diabetes. There were no differences between the prediabetes defined by the ADA and the WHO for predicting the onset of the disease.

Prevalence of Prediabetes and Undiagnosed Diabetes in Canada (2007-2011) According to Fasting Plasma Glucose and HbA1c Screening Criteria

OBJECTIVE

To provide the first population-based estimates of prediabetes and undiagnosed type 2 diabetes prevalence in Canada.

RESEARCH DESIGN AND METHODS

We combined two fasting subsamples of the Canadian Health Measures Survey, which were restricted to nonpregnant adults ≥20 years of age (N = 3,494). Undiagnosed diabetes was defined as not having self-reported type 2 diabetes but having blood glucose measures that met Canadian guidelines (i.e., fasting plasma glucose [FPG] level of ≥7.0 mmol/L or hemoglobin A1c [HbA1c] level of ≥6.5% [≥48 mmol/mol]). Prediabetes was defined as an FPG level of ≥6.1 and <7.0 mmol/L or an HbA1c level of ≥6.0% and <6.5% (≥42 and <48 mmol/mol). All estimates were weighted using survey sampling weights. CIs were calculated with the bootstrap method.

RESULTS

According to FPG levels, the prevalence of undiagnosed type 2 diabetes in Canadian adults was 1.13% (95% CI 0.79, 1.62), contributing to ∼20% of total type 2 diabetes prevalence (5.62 [95% CI 4.52, 6.95]). Compared with FPG levels, the undiagnosed prevalence was greater using HbA1c level as a criterion (3.09% [95% CI 1.97, 4.81]), ∼41% of the total number of cases of diabetes (7.55 [95% CI 5.98, 9.49]). The HbA1c-only criterion resulted in a threefold increase in prediabetes prevalence overall and a sixfold increase among females (FPG 2.22%, HbA1c 13.31%). Screening based on FPG only identified older undiagnosed case patients, with a mean age of 58.7 years (95% CI 59.9, 63.4). Similarly, using HbA1c identified younger individuals with prediabetes, with reduced BMI and waist circumference compared with FPG levels.

CONCLUSIONS

In this first study of a nationally representative sample with biospecimen measures, we found that the prevalence of undiagnosed type 2 diabetes and prediabetes was significantly higher using HbA1c levels compared with FPG levels. Further evaluation is needed to fully assess the impact of using the HbA1c criterion.

Influence of the glycation gap on the diagnosis of type 2 diabetes

AIMS

The results of using HbA1C-based criteria for diagnosis of type 2 diabetes and prediabetes have been reported to differ from those obtained using fasting plasma glucose (FPG) or an oral glucose tolerance test (OGTT). We aimed to determine whether these discrepancies might be due to the influence of the glycation gap.

METHODS

For 430 patients without previously diagnosed diabetes for whom an OGTT had been requested in normal clinical practice, FPG, fructosamine and HbA1C were measured at the time of the test and again 1 month later. Glycaemia/diabetes status was classified as normoglycaemia, prediabetes or diabetes using both HbA1C-based and FPG/OGTT-based criteria, and their glycation gaps GG were calculated.

RESULTS

The specificity of an HbA1C level of 6.5 % (48 mmol/mol) for diagnosis of FPG/OGTT-defined type 2 diabetes was 99 %, but its sensitivity was less than 37 %. HbA1C-diabetic patients had higher average blood glucose levels than FPG/OGTT-diabetic patients. With either set of criteria, high-GG patients were disproportionately numerous among those classified as diabetic and were disproportionately infrequent among those classified as normoglycaemic, but the effect was greater for the HbA1C criteria.

CONCLUSIONS

The differences between HbA1C-based and FPG/OGTT-based diagnoses are largely due to the influence of the glycation gap, which may also influence the early stages of FPG/OGTT-defined diabetes.

Unfavorable inflammatory profile in adults at risk of type 2 diabetes identified by hemoglobin A1c levels according to the American Diabetes Association criteria

AIMS

We aimed to evaluate the inflammatory profile of individuals with prediabetes defined by HbA1c levels, according to the new American Diabetes Association criteria, and to determine the ability of HbA1c to identify individuals with subclinical inflammation independently of the contribution of other metabolic parameters such as fasting, 1- or 2-h post-load glucose (PG) levels.

METHODS

High sensitivity C-reactive protein (hsCRP), erythrocyte sedimentation rate (ESR), fibrinogen, white blood cells (WBC) count and complement C3 (C3) were assessed, and oral glucose tolerance test (OGTT) was performed in 711 adults.

RESULTS

Subjects were stratified into three groups according to their HbA1c levels. Poor agreement existed between HbA1c and 2-h PG criteria for identification of individuals with prediabetes (κ coefficient = 0.300). As compared with subjects having HbA1c <5.7 % (39 mmol/mol), individuals with prediabetes (HbA1c 5.7-6.4 %, [39-46 mmol/mol]) exhibited a significant increase of the concentration of five inflammatory markers (hsCRP, ESR, fibrinogen, WBC count, C3) as well as of a cluster of inflammatory markers, as measured by an inflammatory score after adjusting for sex, age, smoking, fasting, 1- and 2-h PG levels. In multiple regression models including sex, age, body mass index, smoking habit, fasting, 1- and 2-h PG levels, and HOMA index, HbA1c levels were significant independent contributors to each of the five inflammatory markers examined.

CONCLUSIONS

These data suggest that HbA1c is a reliable marker of glucose homeostasis, and may identify individuals at increased risk of diabetes with unfavorable inflammatory profile independently from fasting and 2-h PG levels.

Secular changes in prediabetes indicators among older-adult Americans, 1999-2010

BACKGROUND

Sex-specific prediabetes estimates are not available for older-adult Americans.

PURPOSE

To estimate prediabetes prevalence, using nationally representative data, in civilian, non-institutionalized, older U.S. adults.

METHODS

Data from 7,995 participants aged ≥50 years from the 1999-2010 National Health and Nutrition Examination Surveys were analyzed in 2013. Prediabetes was defined as hemoglobin A1c=5.7%-6.4% (39-47 mmol/mol [HbA1c5.7]), fasting plasma glucose of 100-125 mg/dL (impaired fasting glucose [IFG]), or both. Crude and age-adjusted prevalences for prediabetes, HbA1c5.7, and IFG by sex and three age groups were calculated, with additional adjustment for sex, age, race/ethnicity, poverty status, education, living alone, and BMI.

RESULTS

From 1999 to 2005 and 2006 to 2010, prediabetes increased for adults aged 50-64 years (38.5% [95% CI=35.3, 41.8] to 45.9% [42.3, 49.5], p=0.003) and 65-74 years (41.3% [37.2, 45.5] to 47.9% [44.5, 51.3]; p=0.016), but not significantly for adults aged ≥75 years (45.1% [95% CI=41.1, 49.1] to 48.9% [95% CI=45.2, 52.6]; p>0.05). Prediabetes increased significantly for women in the two youngest age groups, and HbA1c5.7 for both sexes (except men aged ≥75 years), but IFG remained stable for both sexes. Men had higher prevalences than women for prediabetes and IFG among adults aged 50-64 years, and for IFG among adults aged ≥75 years. Across demographic subgroups, adjusted prevalence gains for both sexes were similar and most pronounced for HbA1c5.7, virtually absent for IFG, but greater for women than men for prediabetes.

CONCLUSIONS

Given the large, growing prediabetes prevalence and its anticipated burden, older adults, especially women, are likely intervention targets.