Ethnic differences in the relationship of prediabetes with the presence of target-organ disease

Prevalence of atherosclerosis in individuals with prediabetes and diabetes compared to normoglycaemic individuals-a Swedish population-based study

BACKGROUND

Patients with type 2 diabetes have an increased risk of death and cardiovascular events and people with diabetes or prediabetes have been found to have increased atherosclerotic burden in the coronary and carotid arteries. This study will estimate the cross-sectional prevalence of atherosclerosis in the coronary and carotid arteries in individuals with prediabetes and diabetes, compared with normoglycaemic individuals in a large population-based cohort.

METHODS

The 30,154 study participants, 50-64 years, were categorized according to their fasting glycaemic status or self-reported data as normoglycaemic, prediabetes, and previously undetected or known diabetes. Prevalence of affected coronary artery segments, severity of stenosis and coronary artery calcium score (CACS) were determined by coronary computed tomography angiography. Total atherosclerotic burden was assessed in the 11 clinically most relevant segments using the Segment Involvement Score and as the presence of any coronary atherosclerosis. The presence of atherosclerotic plaque in the carotid arteries was determined by ultrasound examination.

RESULTS

Study participants with prediabetes (n = 4804, 16.0%) or diabetes (n = 2282, 7.6%) had greater coronary artery plaque burden, more coronary stenosis and higher CACS than normoglycaemic participants (all, p < 0.01). Among male participants with diabetes 35.3% had CACS ≥ 100 compared to 16.1% among normoglycaemic participants. For women, the corresponding figures were 8.9% vs 6.1%. The prevalence of atherosclerosis in the coronary arteries was higher in participants with previously undetected diabetes than prediabetes, but lower than in patients with known diabetes. The prevalence of any plaque in the carotid arteries was higher in participants with prediabetes or diabetes than in normoglycaemic participants.

CONCLUSIONS

In this large population-based cohort of currently asymptomatic people, the atherosclerotic burden in the coronary and carotid arteries increased with increasing degree of dysglycaemia. The finding that the atherosclerotic burden in the coronary arteries in the undetected diabetes category was midway between the prediabetes category and patients with known diabetes may have implications for screening strategies and tailored prevention interventions for people with dysglycaemia in the future.

Prevalence of Prediabetes and Abdominal Obesity Among Healthy-Weight Adults: 18-Year Trend

PURPOSE

Trends in sedentary lifestyle may have influenced adult body composition and metabolic health among individuals at presumably healthy weights. This study examines the nationally representative prevalence of prediabetes and abdominal obesity among healthy-weight adults in 1988 through 2012.

METHODS

We analyzed the National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and NHANES for the years 1999 to 2012, focusing on adults aged 20 years and older who have a body mass index (BMI) of 18.5 to 24.99 and do not have diabetes, either diagnosed or undiagnosed. We defined prediabetes using glycated hemoglobin (HbA1c) level ranges from 5.7% to 6.4%, as specified by the American Diabetes Association. Abdominal obesity was measured by waist circumference and waist-to-height ratio.

RESULTS

The prevalence of prediabetes among healthy-weight adults, aged 20 years and older and without diagnosed or undiagnosed diabetes, increased from 10.2% in 1988-1994 to 18.5% in 2012. Among individuals aged 45 years and older, the prevalence of prediabetes increased from 22.0% to 33.1%. The percentage of adults aged 20 years and older with an unhealthy waist circumference increased from 5.6% in 1988-1994 to 7.6% in 2012. The percentage of individuals with an unhealthy waist-to-height ratio increased from 27.2% in 1988-1994 to 33.7% in 2012. Adjusted models found that measures of abdominal obesity were not independent predictors of prediabetes among adults with a healthy BMI.

CONCLUSIONS

Among individuals within a healthy BMI range, the prevalence of prediabetes and abdominal obesity has substantially increased. Abdominal obesity does not appear to be the primary cause of the increase.

Relationship between dyslipidemia and albuminuria in prediabetic adults: the Korea National Health and Nutrition Examination Survey 2011-2012

This study aimed to estimate the relationship between various lipid abnormalities and albuminuria in Korean prediabetic adults. Data obtained from the Korea National Health and Nutrition Examination Survey (KNHANES) 2011-2012 were analyzed. The study consisted of 4,811 subjects in the normal glucose group and 3,872 in the prediabetic group. Prediabetes was defined by the fasting plasma glucose or hemoglobin A1c level. Albuminuria was defined as a urine albumin to creatinine ratio (UACR) ≥30 mg/g. Various parameters of dyslipidemia were assessed. No differences were observed in the prevalence of lipid abnormalities in prediabetic men with different values of UACR. Prediabetic women with increased urinary albumin excretion showed a significantly higher prevalence of lipid abnormalities. The proportion of mixed dyslipidemia was significantly higher in prediabetic women with albuminuria. Higher levels of total cholesterol, triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), and TC to HDL-C ratio, TG to HDL-C ratio, and LDL-C to HDL-C ratio were significantly associated with increased risk of albuminuria in prediabetic women.

CONCLUSIONS

Several lipid abnormalities were significantly associated with the increased risk of albuminuria in prediabetic women. Hence, screening for lipid abnormalities may be helpful for identification of risk for albuminuria in prediabetic subjects.

Cytokine profiling of young overweight and obese female African American adults with prediabetes

Approximately 5-10% of subjects with prediabetes become diabetic every year. Inflammation is involved in the development of obesity-related type 2 diabetes (T2D). However, to date, the relationship between inflammation and prediabetes, defined by hemoglobin A1c (HbA1c) ≥5.7 and <6.5%, remains largely unexplored, especially in African Americans. Therefore, in this study we examined a comprehensive panel of 13 cytokines involved in the inflammatory response in overweight/obese subjects with prediabetes. A total of 21 otherwise healthy, overweight/obese, young adult African American females with prediabetes, together with 20 matched overweight/obese controls, were selected for this study. Plasma cytokines were assessed by multiplex cytokine profiling. Plasma concentrations of interleukin (IL)-5, IL-6, IL-7, tumor necrosis factor-α (TNF-α), and granulocyte-monocyte colony-stimulating factor (GM-CSF) were significantly higher in the prediabetic group, as compared to the control group (all p<0.05). Plasma concentrations of all the other cytokines, interferon-γ (IFN-γ), IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12p70 and IL-13, seemed to be elevated in the prediabetic group, but failed to reach statistical significances. Upon merging both groups, HbA1c was found to be positively correlated with IFN-γ, IL-1β, IL-2, IL-5, IL-7, IL-8, TNF-α and GM-CSF. This study demonstrates elevated levels of various pro-inflammatory cytokines in overweight/obese young subjects with prediabetes, which place them at higher risk of developing T2D and cardiovascular diseases. Our data also call for further investigations in animal models and population cohorts to establish the roles of a variety of pro-inflammatory cytokines in the early development of obesity-related T2D.

High prevalence of coexisting prehypertension and prediabetes among healthy adults in northern and northeastern China

Background

Prehypertension and prediabetes are major risk factors of cardiovascular disease, and their combined presence may result in more serious cardiovascular outcomes than expected with either prehypertension or prediabetes alone. The aim of the present study was to evaluate the prevalence of coexisting prehypertension and prediabetes, and the associated risk profiles in a Chinese population.

Methods

A cross-sectional survey in a representative sample of 3,595 men and 4,593 women aged 18 years and older was performed between 2008 and 2010. Prehypertension and prediabetes were diagnosed using the guidelines from the Seventh Report of the Joint National Committee on prevention, detection, and treatment of high blood pressure and American Diabetes Association, respectively. Prehypertension was defined as a systolic blood pressure of 120-139 mmHg and/or diastolic blood pressure of 80-89 mmHg, and prediabetes was defined as a fasting blood glucose of 5.6-6.9 mmol/L.

Results

The prevalence of coexisting prehypertension and prediabetes was 11.0%. Men had a higher prevalence of coexisting prehypertension and prediabetes than women (14.2% vs. 8.4%; P < 0.0001). This prevalence increased with age and body mass index, and was the lowest among Mongolian-Chinese (5.1%). A multivariate analysis showed that γ-glutamyltransferase and uric acid were significantly and positively correlated with body mass index, waist circumference, blood pressure, triglycerides, and total cholesterol, and negatively correlated with high density lipoprotein cholesterol in subjects with prehypertension and prediabetes.

Conclusions

There is a large proportion of Chinese adults with coexisting prehypertension and prediabetes. Thus, there is a need for more efforts that implement public health programs that target the earlier stages of hypertension and diabetes.