Association between hemoglobin A1c, carotid atherosclerosis, arterial stiffness, and peripheral arterial disease in Korean type 2 diabetic patients

Fasting Glucose, Glycated Hemoglobin, and 2h Post-load Blood Glucose Are Independently Associated With Arterial Stiffness in Diabetes: The ELSA-Brasil Study

The association of diabetes with increased large artery stiffness is not definitively established. We aimed to describe the carotid-femoral pulse wave velocity (cf-PWV) in participants with and without diabetes and whether the cf-PWV could vary among the different laboratory-based criteria used. A cross-sectional analysis using baseline data from 13,912 adults was used. cf-PWV as well as anthropometric, biochemical, and clinical data were measured. Diabetes was defined by previous medical diagnosis, medication use, fasting glucose, an oral glucose tolerance test (GTT), or glycated hemoglobin (HbA1c). The prevalence of diabetes was 18.7%, higher in men than in women. After adjustment, participants with diabetes showed higher cf-PWV (men: 9.7 ± 1.7 vs 9.4 ± 1.7 m/s, P < .05; women: 9.4 ± 1.6 vs 9.1 ± 1.7 m/s, P < .05). We observed a progressive increase in cf-PWV as >1 laboratory-based criterion for diabetes diagnosis was reached. Also, participants with diabetes with alterations in any laboratory-based criteria had higher cf-PWV than participants without diabetes, regardless of sex. In summary, diabetes is associated with higher cf-PWV as is each laboratory-based parameter used for its diagnosis. These results support the strong consequences of glucose dysregulation on the vascular system and provide evidence to screen all parameters involved in glycemic metabolism to improve vascular health.

Factors associated with the elasticity of asymptomatic carotid plaques in hypertension Tibetan population

AIMS

Hypertension is a major risk factor for coronary, cerebrovascular, and the greatest cause of stroke. Half of stroke events are the result of cerebrovascular atherosclerosis, including carotid plaques. It is of major importance to detect which plaques are vulnerable, even though not yet ruptured. Due to the particularity of the Tibetan population, this study evaluated the elasticity of asymptomatic carotid plaques in Tibetan hypertension patients using shear wave elastography (SWE) and explored associated risk factors.

METHODS

A total of 91 Tibetan patients were divided into normotension, grade 1-2, and grade 3 hypertension groups based on the level of blood pressure. All subjects underwent common duplex ultrasonic examination and SWE evaluation for carotid plaques. Elasticity of carotid plaque was assessed by Young's modulus.

RESULTS

The final analysis included 126 plaques as representative plaques according to Total Plaque Risk Score. The mean and maximum Young's modulus in the grade 3 hypertension group were smaller, and more plaques with irregularity surface compared with the other two groups (p < 0.05). Multivariate regression analysis showed drinking butter tea (β = -0.220, p = 0.009; β = -0.240, p = 0.004, respectively) was the independent factor associated with mean and maximum Young's modulus.

CONCLUSIONS

SWE is feasible for measurement of Young's modulus of carotid plaques. Plaques in the grade 3 hypertension group were more likely to become vulnerable ones. In hypertension Tibetan patients, drinking butter tea was an independent factor associated with mean and maximum Young's modulus of asymptomatic carotid plaque.

Mean and variability of annual haemoglobin A1c are associated with high-risk peripheral artery disease

BACKGROUND

Glucose variability is predictive of cardiovascular events and all-cause mortality. However, the association between peripheral artery disease and glucose variability has not been thoroughly investigated. Therefore, the standard deviation of annual haemoglobin A1c was assessed in patients with type 2 diabetes for evaluating the different risks of peripheral artery disease.

METHODS

A total of 4144 patients underwent an evaluation for the ankle-brachial index and the percentage of mean arterial pressure at the ankle. The first haemoglobin A1c record was retrospectively collected from each year until the ankle-brachial index measurement.

RESULTS

The standard deviation of annual haemoglobin A1c was higher in patients with ankle-brachial index ⩽0.90 than in those with ankle-brachial index >0.90 (1.1 ± 0.9% vs 1.0 ± 0.8%, p = 0.009) and was higher in patients with percentage of mean arterial pressure ⩾45% than in those with percentage of mean arterial pressure <45% (1.1 ± 0.8% vs 1.0 ± 0.8%, p = 0.007). A high standard deviation and mean of annual haemoglobin A1c are associated with high-risk peripheral artery disease, which is defined as a combination of ankle-brachial index ⩽0.90, percentage of mean arterial pressure ⩾45% or both (odds ratio = 1.306; 95% confidence interval = 1.057-1.615; p = 0.014).

CONCLUSION

Fluctuation in the haemoglobin A1c value indicates higher risk for peripheral artery disease in patients with type 2 diabetes and poor glucose control.

Relationship Between Glycated Haemoglobin and Carotid Atherosclerotic Disease Among Patients with Acute Ischaemic Stroke

Objectives

This study aimed to determine the relationship between glycaemic control and carotid atherosclerotic disease among patients with acute ischaemic stroke (AIS).

Methods

This retrospective cross-sectional study took place in the Neurology Department of King Fahad Hospital of University, Khobar, Saudi Arabia, from April to October 2017. Data were collected from the medical records of 244 patients with a diagnosis of AIS confirmed by computed tomography. Doppler ultrasounds of the carotid artery were performed to determine the presence of increased carotid intima media thickness (CIMT) and plaques.

Results

Significantly higher mean glycated haemoglobin (HbA1c) levels were noted in cases with high CIMT values (P = 0.002), but not in cases with carotid plaques (P = 0.360). In addition, there was a significant association between diabetes mellitus (DM) and high CIMT (P = 0.045), but not with carotid plaques (P = 0.075). Finally, while dyslipidaemia and age were independently correlated with high CIMT values (P = 0.034 and <0.001, respectively) and carotid plaques (P <0.001 each), no independent relationships were noted in terms of gender and other risk factors like DM, hypertension and smoking (P >0.050 each).

Conclusion

High HbA1c levels were associated with high CIMT values, but not with carotid plaques. Therefore, HbA1c levels may be useful as an indirect marker of the initial stages of carotid artery atherosclerosis.

Factors associated with carotid Intima media thickness and carotid plaque score in community-dwelling and non-diabetic individuals

Background

The carotid intima media thickness (cIMT) and carotid plaque score (cPS) are respective markers of early and late stage subclinical atherosclerosis. Relationships between some laboratory parameters and subclinical atherosclerosis are not yet clear in community dwelling individuals and non-diabetic subjects, so we try to elucidate these relationships and find a model to predict early and late stage subclinical atherosclerosis.

Methods

We examined relationships of the cIMT and cPS with different laboratory and demographic data of 331 subjects from a community-based prospective cohort study, using univariate and multivariate analyses.

Results

In regression models and after multiple adjustments, only systolic blood pressure (SBP), age, glycated hemoglobin (HBA1c), and waist circumference (WC) were determinants of the cIMT, and only age, SBP, HBA1c, and blood urea nitrogen (BUN) were determinants of a cPS of > 2 in all individuals. Only HBA1c lost its association with regard to predicting the cIMT in non-diabetic subjects.

Conclusions

HBA1c at > 5.9% can determine early and late stage subclinical atherosclerosis in community dwelling individuals, but only late stage subclinical atherosclerosis in non-diabetic subjects.

Glycated Hemoglobin and All-Cause Mortality in Korean Type 2 Diabetes

The purpose of this study was to evaluate the association between glycated hemoglobin (HbA1c) and all-cause mortality in type 2 diabetes mellitus. We conducted a community-based prospective cohort study of 352 type 2 diabetic patients aged 30-92 who participated in a community diabetes complications screening program in Gokseng-gun, Jeollanamdo, Korea. HbA1c levels were categorized as <6.5%, 6.5-6.9%, 7.0-7.9%, 8.0-8.9% and ≥9.0%. Patients were followed up on for a mean of 6.9 years. The Cox proportional hazards model was used to evaluate the relationship between HbA1c levels and all-cause mortality. During the mean follow-up period of 6.9 years, 77 patients (21.9%) died. A J-shaped association was found between HbA1c and all-cause mortality, with the lowest mortality at 6.5-6.9% of HbA1c levels. Compared to patients with HbA1c of 6.5-6.9%, patients with <6.5%, 7.0-7.9%, 8.0-8.9% and ≥9.0% had an adjusted hazard ratio (95% confidence interval) for all-cause mortality of 1.71 (0.76-3.84), 1.23 (0.53-2.82), 1.32(0.51-3.44) and 2.66 (1.01-7.02), respectively. We found a J-shaped association between glycated hemoglobin and all-cause mortality in Korean type 2 diabetic patients.

Association between Vascular Endothelial Markers and Carotid Intima-Media Thickness in Children and Adolescents with Type 1 Diabetes Mellitus

Introduction

Type 1 Diabetes Mellitus (T1DM) is one of the important risk factor for cardiovascular disease. Endothelial dysfunction and increased Carotid Intima-Media Thickness (CIMT) result in cardiovascular complications. Vascular Cell Adhesion Molecule-1 (VCAM-1) and Intercellular Adhesion Molecule-1 (ICAM-1) are two adhesion molecules that are markers of early atherosclerosis and play a significant role in developing atherosclerosis.

Aim

To evaluate CIMT and its association with the levels of ICAM-1 and VCAM-1 in children and adolescents with T1DM.

Materials and Methods

In this descriptive, cross-sectional study conducted between April 2013 and September 2014, 29 children aged 7-20 years with T1DM for at least two years and 29 age and sex-matched, healthy individuals were evaluated. Plasma level of ICAM-1 and VCAM-1 was measured by ELISA, and CIMT via Doppler ultrasound was also assessed. The data were analysed by t-test and Pearson's correlation coefficient in SPSS 16.0 (p≤0.05).

Results

Independent t-test indicated that there is a significant difference in ICAM-1 level between the patients and controls (p<0.001). Further, CIMT was significantly higher in diabetic subject (p<0.001). CIMT was not significantly associated with the level of VCAM-1 and ICAM-1 in the patients (p>0.5).

Conclusion

ICAM-1 and VCAM-1 were not associated with CIMT but, CIMT and level of ICAM-1 were significantly, higher in diabetic patients, and therefore could be used as useful tools for identification of early atherosclerosis in children and adolescents with T1DM.

Association between HbA1c and carotid atherosclerosis among elderly Koreans with normal fasting glucose

Aim

We examined whether glycated haemoglobin (HbA1c) is associated to carotid atherosclerosis in an elderly Korean population with normal fasting glucose.

Methods

Using data from the Korean Urban Rural Elderly study, we conducted a cross-sectional analysis of 1,133 participants (335 men and 798 women) with a mean age of 71.8 years. All participants had fasting blood glucose less than 100mg/dL (5.6 mmol/L) and HbA1c level below 6.5% (48 mmol/mol). They were also free from a history of cardiovascular disease, known type 2 diabetes mellitus or use of anti-diabetes medications. Carotid atherosclerosis was assessed by intima-media thickness (IMT) using ultrasonography. The association between HbA1c and carotid IMT was investigated using multivariable linear regression analysis.

Results

HbA1c levels were independently and positively associated with carotid IMT (β = 0.020, p = 0.045) after adjusting for sex, age, body mass index, systolic blood pressure, diastolic blood pressure, triglyceride, LDL cholesterol, smoking and alcohol intake. However, fasting insulin and glucose levels were not associated with carotid IMT.

Conclusion

HbA1c levels were positively associated with carotid atherosclerosis, as assessed by carotid IMT, in an elderly population with normoglycemia. Our study suggested that higher HbA1c level is an effective and informative marker of carotid atherosclerosis in an elderly population.

Association between markers of glycemia and carotid intima-media thickness: the MARK study

BACKGROUND

Carotid intima-media thickness (C-IMT) is a reliable predictor of cardiovascular events. We Investigated the relationship between markers of glycemia and C-IMT in intermediate-risk cardiovascular patients.

METHODS

This study analyzed 427 subjects, aged 35 to 74 years (mean, 60.3 ± 8.5 years), 55 % women, enrolled into the MARK study. Including 231 subjects defined as normal glucose, 104 subjects classified as prediabetes and 92 with type 2 diabetes mellitus. Carotid ultrasound was used to measure C-IMT and the presence of plaques. Fasting plasma glucose (mg/dl) and glycated hemoglobin (%) (HbA1c) were measured using standard enzymatic automated methods. Postprandial glucose (mg/dl) was self-measured by patients at home 2 h after meals (breakfast, lunch and dinner) for 1 day.

RESULTS

The C-IMT shows a positive correlation with fasting plasma glucose, postprandial glucose and HbA1c. Multiple linear regression analysis showed a positive association between HbA1c and C-IMT, with a 0.016 mm and 0.019 mm increase in mean and maximum C-IMT per 1 % increase in HbA1c. In addition, an association between fasting plasma glucose and C-IMT was found with an increase of 0.004 and 0.005 mm in mean and maximum C-IMT per 10 mg/dl in fasting plasma glucose. We also observed a graded association between fasting plasma glucose, postprandial glucose and HbA1c and the presence of carotid target organ damage (TOD), with an odds ratio of 1.013, 1.010 and 1.425, respectively.

CONCLUSION

The results of this study suggest that the fasting plasma glucose and HbA1c, but not postprandial glucose, are associated with C-IMT media and maximum. The patients who present with a metabolic glucose alteration have more risk of developing carotid TOD.

TRIAL REGISTRATION

ClinicalTrials.gov; Identifier: NCT01428934 .

HbA1c is significantly associated with arterial stiffness but not with carotid atherosclerosis in a community-based population without type 2 diabetes: The Dong-gu study

OBJECTIVES

We examined the associations between HbA1c levels and various atherosclerotic vascular parameters among adults without diabetes from the general population.

METHODS

A total of 6500 community-dwelling adults, who were free of type 2 diabetes and ≥50 years of age, were included. High-resolution B-mode ultrasound was used to evaluate carotid artery structure, including intima-media thickness (IMT), plaque, and luminal diameter. Brachial-ankle pulse wave velocity (baPWV), which is a useful indicator of systemic arterial stiffness, was determined using an automatic waveform analysis device.

RESULTS

No significant associations were observed between HbA1c, carotid IMT, plaque, or luminal diameter in a fully adjusted model. However, the odds ratio (95% confidence interval) for high baPWV (defined as the highest quartile) increased by 1.43 (1.19-1.71) per 1% HbA1c increase after adjusting for conventional risk factors in a multivariate logistic regression analysis. In addition, HbA1c was independently associated with baPWV in a multivariate linear regression analysis.

CONCLUSIONS

High-normal HbA1c level was independently associated with arterial stiffness, but not with carotid atherosclerotic parameters, in the general population without diabetes. Our results suggest that the functional atherosclerotic process may already be accelerated according to HbA1c level, even at a level below the diagnostic threshold for diabetes.

Paradox of using intensive lowering of blood glucose in diabetics and strategies to overcome it and decrease cardiovascular risks

Hyperglycemia significantly increases the risk of cardiovascular disease (CVD) in diabetics. However, it has been shown by a series of large scale international studies that intensive lowering of blood glucose levels not only has very limited benefits against cardiovascular problems in patients, but may even be harmful to patients at a high risk for CVD and/or poor long-term control of blood glucose levels. Therefore, Western medicine is faced with a paradox. One way to solve this may be administration of Chinese herbal medicines that not only regulate blood glucose, blood fat levels and blood pressure, but also act on multiple targets. These medicines can eliminate cytotoxicity of high glucose through anti-inflammatory and anti-oxidant methods, regulation of cytokines and multiple signaling molecules, and maintenance of cell vitality and the cell cycle, etc. This allows hyperglycemic conditions to exist in a healthy manner, which is called "harmless hyperglycemia" Furthermore, these cardiovascular benefits go beyond lowering blood glucose levels. The mechanisms of action not only avoid cardiovascular injury caused by intensive lowering of blood glucose levels, but also decrease the cardiovascular dangers posed by hyperglycemia.

Comparison of carotid and lower limb atherosclerotic lesions in both previously known and newly diagnosed type 2 diabetes mellitus

Aims/Introduction

To compare carotid and lower limb atherosclerotic lesions, and examine if carotid atherosclerotic lesions are in line with lower limb atherosclerotic lesions, and can reflect generalized atherosclerosis in inpatients with type 2 diabetes.

Materials and Methods

This was an observational study carried out in 867 Chinese inpatients with type 2 diabetes, including 573 previously known and 294 newly diagnosed patients. Ultrasonographic assessments of intima-media thickness (IMT), plaques, and stenosis in the carotid and lower limb arteries were evaluated. Atherosclerotic lesions between the carotid and lower limb arteries were compared in both previously known and newly diagnosed diabetes, respectively.

Results

In both the known (77.3% vs 49.4%, P < 0.001) and the newly diagnosed diabetes (55.4% vs 29.9%, P < 0.001), the prevalence of atherosclerotic plaques was significantly higher in the lower limb arteries than in the carotid arteries. Likewise, the prevalence of stenosis was also significantly higher (P < 0.001) in the lower limb arteries (16.9%) than in the carotid arteries (4.2%) in the established diabetes patients. However, there was no significant difference in the mean IMT between common carotid and common femoral arteries in both the previously known (0.90 ± 0.24 mm vs 0.89 ± 0.20 mm, P = 0.675) and the newly diagnosed diabetes patients (0.86 ± 0.22 mm vs 0.85 ± 0.16 mm, P = 0.436).

Conclusions

Carotid plaques might underestimate generalized plaques in inpatients with type 2 diabetes, as shown by its significantly lower prevalence compared with that of the lower extremity arteries. A combined carotid and lower limb ultrasound examination can improve the detection of atherosclerotic lesions in inpatients with type 2 diabetes.

Associations between blood glucose and carotid intima-media thickness disappear after adjustment for shared risk factors: the KORA F4 study

Objective

The association between blood glucose and carotid intima-media thickness (CIMT) is considered to be established knowledge. We aimed to assess whether associations between different measures of glycaemia and CIMT are actually independent of anthropometric variables and metabolic risk factors. Moreover, we checked published studies for the adjustment for shared risk factors of blood glucose and CIMT.

Methods

Fasting glucose, 2-hour glucose, HbA1c, and CIMT were measured in 31-81-years-old participants of the population-based Cooperative Health Research in the Region of Augsburg (KORA) F4 study in Southern Germany (n = 2,663). CIMT was assessed according to the Rotterdam protocol. Linear and logistic regression models with adjustment for age, sex, anthropometric measures, hypertension, and dyslipidaemia were fitted to assess the association between continuous measures of glycaemia, and categories of glucose regulation, respectively, with CIMT.

Results

We found a 0.10 mm increase (95%-confidence interval: 0.08–0.12) in CIMT in subjects with compared to subjects without diabetes in crude analysis. This increase was not significant in age-sex adjusted models (p = 0.17). Likewise, neither impaired fasting glucose (p = 0.22) nor impaired glucose tolerance (p = 0.93) were associated with CIMT after adjustment for age, sex, and waist circumference. In multivariable adjusted models, age, sex, hypertension, waist circumference, HDL and LDL cholesterol, but neither fasting glucose nor 2-hour glucose nor HbA1c were associated with elevated CIMT. Literature findings are inconclusive regarding an independent association of glucose levels and CIMT.

Conclusion

CIMT is highly dependent on traditional cardiovascular risk factors, but no relationships between blood glucose and CIMT were found after adjustment for age, sex, and anthropometric variables.

Association between total bilirubin and hemoglobin A1c in Korean type 2 diabetic patients

Recent studies have shown that bilirubin is negatively associated with hemoglobin A1c (HbA1c) in the general population. The association between bilirubin and HbA1c in serum of diabetes patients has not yet been studied. The aim of the present study was to evaluate the association between total bilirubin and HbA1c in Korean patients with type 2 diabetes. A total of 690 of the 1,275 type 2 diabetes patients registered with the public health centers in Seo-gu, Gwangju and Gokseong-gun, Jeollanam-do participated in this study. Following an overnight fast, venous blood and urine samples were collected and analyzed. The mean HbA1c values differed significantly according to total bilirubin (≤ 0.4 mg/dL, 7.6%; 0.5 mg/dL, 7.3%; 0.6-0.7 mg/dL, 7.2%; and ≥ 0.8 mg/dL, 7.1%; P for trend = 0.016) after we adjusted for other confounding factors. When the odds ratio (OR) was adjusted for other confounding factors, there was a significant association between total bilirubin and HbA1c (OR, 0.4 [95% confidence interval, 0.2-0.8] for total bilirubin ≥ 0.8 mg/dL versus ≤ 0.4 mg/dL. In conclusion, total bilirubin concentrations in serum are negatively associated with HbA1c levels after adjustment for sex, age, and other confounding factors in type 2 diabetes patients.

The prevalence and correlation of carotid artery calcification on panoramic radiographs and peripheral arterial disease in a population from the Republic of Korea: the Dong-gu study

OBJECTIVES

The aim of this study was to determine the prevalence of carotid artery calcification (CAC) detected on panoramic radiographs and peripheral arterial disease (PAD), and to evaluate the difference in the prevalence of PAD between patients with CAC and patients without CAC detectable by panoramic radiograph.

METHODS

The surveyed population consisted of 4078 subjects aged 50 years and older (1410 males and 2668 females) who underwent medical and dental examination in Gwangju city, South Korea. Two oral and maxillofacial radiologists interpreted the panoramic radiographs for the presence of carotid artery calcification. A trained research technician measured the ankle-brachial index (ABI). An ABI <0.9 in either leg was considered evidence of PAD.

RESULTS

The prevalence of CAC on panoramic radiographs was 6.2% and that of PAD was 2.6%. Subjects with CAC had a significantly higher prevalence of PAD than those without CAC (5.5% vs 2.4%, respectively). The presence of CAC on panoramic radiographs was associated with PAD (odds ratio 1.84; 95% confidence interval 1.01-3.36) after adjusting for potential confounders.

CONCLUSION

CACs detected on panoramic radiographs were positively associated with PAD in middle-aged and older Korean adults.

Prevalence of atherosclerotic plaque in young and middle-aged asymptomatic individuals: the Bogalusa heart study

OBJECTIVES

To determine the prevalence of carotid and femoral artery atherosclerotic plaque in a community-based population of asymptomatic African American and white men and women, with an age range of 29 to 51 years, and the potential relations with cardiovascular risk factors.

METHODS

Between 2007 and 2010, 914 subjects, 58% women and 69% white, who were part of the Bogalusa Heart Study, an ongoing study of a southern biracial community in Bogalusa, Louisiana, were followed up from childhood through adulthood and assessed for plaque formation using ultrasound. Of the total number of subjects, those with a history of cardiovascular/cerebrovascular events were excluded.

RESULTS

Plaque prevalence ranged from 8% to 14%, with greater frequency in white men. Plaque formation was also associated with smoking, hypertension, diabetes mellitus, age, and white race, in descending order.

CONCLUSIONS

In this population, studied sequentially since 1973, the presence of plaque correlated with widely recognized cardiovascular risk factors, although we did not detect significant contributions from either obesity or elevated lipids, including low-density lipoprotein cholesterol. It is possible that interventions, such as diet alteration and statin therapy, may have a positive impact on these potential contributors to plaque formation, and hypertension, diabetes mellitus and smoking remain of great importance.