The association of brachial-ankle pulse wave velocity with 30-minute post-challenge plasma glucose levels in korean adults with no history of type 2 diabetes

One-Hour Post-Load Plasma Glucose Levels are Associated with Early Arterial Stiffness in Subjects with Different Glucose Tolerance

OBJECTIVE

The purpose of this study was to explore the relationship between one-hour post-load plasma glucose levels and early arterial stiffness in subjects with different glucose tolerance.

METHODS

This case-control study included 57 subjects with normal glucose tolerance, 38 subjects with pre-diabetes, and 30 subjects with type 2 diabetes. All subjects underwent an oral glucose tolerance test (OGTT) with 75 g of oral anhydrous glucose at 8:00 AM. The brachial-ankle pulse wave velocity (baPWV) was used as a surrogate marker of early arterial stiffness.

RESULTS

baPWV was significantly higher in the diabetes group than in the normal glucose tolerance group (diabetes group: 1501.8 ± 270.4 cm/s, pre-diabetes group: 1428.6 ± 173.1 cm/s vs normal glucose tolerance group: 1368.0 ± 242.8 cm/s) (p < 0.05). baPWV was positively correlated with age (r = 0.512, p < 0.001), systolic blood pressure (SBP) (r = 0.526, p < 0.001), diastolic blood pressure (DBP) (r = 0.298, p = 0.001), fasting plasma glucose (FPG) (r = 0.213, p = 0.017), 1-h plasma glucose levels from the OGTT (r = 0.407, p < 0.001) and 2-h plasma glucose levels from the OGTT (r = 0.202, p = 0.024). When baPWV was considered as the dependent variable in a multiple regression analysis, the 1-h plasma glucose level from the OGTT maintained an independent association with baPWV (β = 23.129, 95% CI: 8.142-38.115, p = 0.003, R² = 0.036).

CONCLUSION

The present study demonstrated the presence of early arterial stiffness in diabetes. Elevated 1-hour post-load plasma glucose level is closely related to the change of arterial elasticity in diabetes.

The effect of oral glucose tolerance testing on changes in arterial stiffness and blood pressure in elderly women with hypertension and relationships between the stage of diabetes and physical fitness levels

[Purpose]

The purpose of this study was to assess changes in blood glucose level, blood pressure, and arterial stiffness after a 75 g oral glucose tolerance test (OGTT) in elderly women aged over 65 years with hypertension and either normal glycemic control, impaired fasting glucose tolerance, or diabetes mellitus. We also wished to investigate the relationship between stages of diabetes and physical fitness.

[Methods]

A total of 24 elderly women with hypertension were assigned to a control group (CON; n=7), impaired fasting glucose group (IFG; n=9), and diabetes mellitus group (DM; n=8). In each group, blood glucose level, brachial ankle pulse wave velocity (PWV), and blood pressure were measured at baseline as well as 60 and 120 minutes after a 75 g OGTT. Physical fitness factors such as hand grip strength, balance test, 4 m gait speed test, chair stand test, short physical performance battery, and 6-minute walking test were subsequently assessed.

[Results]

In all three groups, blood glucose levels were significantly increased at 60 and 120 minutes after a 75 g OGTT. In the DM group, blood glucose levels were significantly higher before and after a 75 g OGTT than in the CON group. In the CON group, PWV was significantly increased at 60 minutes after a 75 g OGTT; however, there were no changes in other groups after glucose ingestion. In the CON group, systolic and diastolic blood pressures were significantly decreased at 60 and 120 minutes after a 75 g OGTT compared to baseline. However, there was no change in blood pressure after ingestion in the DM group. The IFG group had greater grip strength than the CON group; however, there were no differences in other variables between the groups.

[Conclusion]

After a 75 g OGTT, elderly women with hypertension and diabetes maintain higher blood glucose levels compared to those with hypertension alone. Unlike elderly women with hypertension alone, those with hypertension and diabetes did not show changes in arterial stiffness and blood pressure after a 75 g OGTT. Therefore, elderly women with hypertension and diabetes may not be able to control their blood vessels following a 75 g OGTT due to impaired vascular endothelial function. Moreover, there was no association between diabetes stage and physical fitness in elderly women with hypertension.

The Temporal Pattern of Arterial Stiffness during Aging: A Large-Scale Cross-Sectional Study

Brachial-ankle pulse wave velocity (baPWV) is a noninvasive clinical test that provides quantification for the stiffness of both the aorta and peripheral arteries by measuring the brachial and tibial arterial wave velocities. The temporal pattern of baPWV values during aging was investigated in this paper. A gradual increase in baPWV with respect to age was observed, suggesting an increase in the stiffness of arterial vessels as age increases. The ΔbaPWV value, defined as the absolute value of the difference between bilateral baPWV, also showed a positive correlation with aging. Many underlying physiological conditions such as hyperlipidemia, hypertension, diabetes, and hyperglycemia have previously been shown to elevate baPWV and contribute to the decline of arterial function. The effect of factors including biological sex, blood pressure, and blood glucose levels on the baPWV temporal pattern were also investigated. Between the ages of 18 and 50, men in the study had significantly higher baPWV readings than females of comparable age on average. However, after the age of 50, mean baPWV values increased at a greater rate in females than in males. In addition, blood pressure and blood glucose were shown to be associated with baPWV values. The results will improve existing prediction models for future cardiovascular episodes induced by arterial hardening in different age groups.

Newly diagnosed abnormal glucose tolerance determines post-MI prognosis in patients with hospital related hyperglycaemia but without known diabetes

AIMS

Investigate if abnormal glucose tolerance (AGT) affects post-myocardial infarction (MI) prognosis in patients with hospital-related hyperglycaemia (HRH) but without known diabetes mellitus (KDM).

METHODS

Post-MI survivors without KDM underwent pre-discharge oral glucose tolerance test. Cardiovascular death and non-fatal re-infarction (MACE) were recorded. We compare the ability of admission (APG), fasting (FPG) and 2 h post-load (2 h-PG) plasma glucose to predict MACE in patients with (HRH) and without HRH (NoHRH).

RESULTS

50.2% and 73% of NoHRH and HRH had AGT respectively. MACE occurred in 19.5% and 18.1% in HRH and NoHRH groups. MACE-free survival was lower in patient with AGT in both groups (NoHRH: HR 1.82, 95% CI 1.19-2.78, p = 0.005; HRH: HR 2.48, 95% CI 1.24-4.96, p = 0.010). AGT predicted MACE-free survival (NoHRH: HR 1.60, 95% CI 1.02-2.51, p = 0.042; HRH: HR 3.09, 95% CI 1.07-8.94, p = 0.037). 2 h-PG, but not FPG or APG, independently predicted MACE free survival (NoHRH: HR 1.17, 95% CI 1.07-1.27, p ≤0.001 and HRH: HR 1.18, 95% CI 1.03-1.37, p = 0.020). Addition of AGT and 2 h-PG, not FPG or APG, improved net reclassification of events in both groups.

CONCLUSION

Post-MI prognosis is worse with AGT irrespective of presence of HRH. 2 h-PG, predicts prognosis in HRH and NoHRH groups.

Adjustment of the GRACE score by 2-hour post-load glucose improves prediction of long-term major adverse cardiac events in acute coronary syndrome in patients without known diabetes

Aims

Global Registry of Acute Coronary Events (GRACE) risk score (GRS), a powerful predictor of prognosis after acute coronary event (ACE), does not include a glucometabolic measure. We investigate whether 2 h post-load plasma glucose (2h-PG) could improve GRS based prognostic models in ACE patients without known diabetes mellitus (DM).

Methods and results

A retrospective cohort study of 1056 ACE survivors without known DM who had fasting plasma glucose (FPG) and 2h-PG measured pre-discharge. Death and non-fatal myocardial infarction were recorded as major adverse cardiac events (MACE) during follow-up. GRS for discharge to 6 months was calculated. Cox proportional-hazards regression was used to identify predictors of event free survival. The predictive value of 2h-PG alone and combined with GRS was estimated using likelihood ratio test, Akaike's information criteria, continuous net reclassification improvement (NRI>0), and integrated discrimination improvement (IDI). During 40.8 months follow-up 235 MACEs (22.3%) occurred, more frequently in the upper 2h-PG quartiles. Two-hour PG, but not FPG, adjusted for GRS independently predicted MACE (hazard ratio 1.091, 95% confidence interval 1.043-1.142; P = 0.0002). likelihood ratio test showed that 2h-PG significantly improved the prognostic models including GRS (χ2 = 20.56, 1 df; P = 0.000). Models containing GRS and 2h-PG yielded lowest corrected Akaike's information criteria, compared to that with only GRS. 2h-PG, when added to GRS, improved net reclassification significantly (NRIe>0 6.4%, NRIne>0 24%, NRI>0 0.176; P = 0.017 at final follow-up). Two-hour PG, improved integrated discrimination of models containing GRS (IDI of 0.87%, P = 0.008 at final follow-up).

Conclusion

Two-hour PG, but not FPG, is an independent predictor of adverse outcome after ACE even after adjusting for the GRS. Two-hour PG, but not FPG, improves the predictability of prognostic models containing GRS.

Two-hour post-challenge glucose is a better predictor of adverse outcome after myocardial infarction than fasting or admission glucose in patients without diabetes

AIMS

We evaluate prevalence of new abnormal glucose tolerance (AGT) in post-MI survivors without known diabetes (DM) if guidelines are followed and compare the ability of admission (APG), fasting (FPG) and 2-h post-load plasma glucose (2h-PG) to predict prognosis.

METHODS

A total of 674 patients were followed up for 4 years for incidence of major adverse cardiovascular events (MACE) of cardiovascular death, non-fatal re-infarction or non-haemorrhagic stroke. Ability of models including APG, FPG and 2h-PG to predict MACE was compared.

RESULTS

Of the total, 93-96% of impaired glucose tolerance and 64-75% of DM would be missed with current guidelines. MACE was higher in the upper quartiles of 2h-PG. When 2h-PG and FPG were included simultaneously in models, only 2h-PG predicted MACE (HR 1.12, CI 1.04-1.20, p = 0.0012), all cause mortality (HR 1.17, CI 1.05-1.30, p = 0.0039), cardiovascular mortality (HR 1.17, CI 1.02-1.33, p = 0.0205) and non-fatal MI (HR 1.10, CI 1.01-1.20, p = 0.0291). Adding 2h-PG significantly improved ability of models including FPG (χ² = 16.01, df = 1, p = 0.0001) or FPG and APG (χ² = 17.36, df = 1, p = 0.000) to predict MACE. Model including 2h-PG only had the lowest Akaike's information criteria and highest Akaike weights suggesting that this was the best in predicting events. Adding 2h-PG to models including FPG or APG with other co-variates yielded continuous net reclassification improvement (NRI) of 0.22 (p = 0.026) and 0.27 (p = 0.005) and categorical NRI of 0.09 (p = 0.032) and 0.12 (p = 0.014), respectively. Adding 2 h-PG to models including only FPG, only APG and both yielded integrated discrimination improvement of 0.012 (p = 0.015), 0.022 (p = 0.001) and 0.013 (p = 0.014), respectively.

CONCLUSIONS

AGT is under-diagnosed on current guidelines. 2h-PG is a better predictor of prognosis compared to APG and FPG.

Investigating the Effect of Glucose on Aortic Pulse Wave Velocity Using Pancreatic Clamping Methodology

Aortic stiffness, determined by carotid-femoral pulse wave velocity (cfPWV), independently predicts cardiovascular outcomes. Recent studies suggest that glucose levels influence arterial stiffness indices. It is not clear, however, whether glucose affects cfPWV independently of glucoregulatory hormones. The aim of this study was to utilize a pancreatic clamping approach to determine whether plasma glucose independently predicts cfPWV. Healthy participants ( N = 10) underwent pancreatic clamping to control glucose at varying concentrations using a 20% dextrose infusion while suppressing endogenous glucagon, insulin, and growth hormone by octreotide and replacing the hormones intravenously to achieve basal concentrations. Tonometric cfPWV, blood pressure, heart rate, plasma glucose, glucagon, insulin, growth hormone, and vasoactive biomarkers were measured. Plasma glucose levels of 150 mg/dl at 1 hr and 200 mg/dl at 2 hr postbaseline were achieved. There were no significant changes in cfPWV (5.8 m/s at 0 hr, 5.9 m/s at 1 hr, and 5.9 m/s at 2 hr) with increased glucose levels. There were small increases in insulin secretion. A definitive role for glucose in cfPWV modulation was not determined; there is a potential role for insulin as a cfPWV modulator. Continued efforts in clarifying the independent roles of glucose and insulin can elucidate novel vessel-related targets for cardiovascular disease prevention and management in patients with impaired glucose tolerance and diabetes.

β-3AR W64R Polymorphism and 30-Minute Post-Challenge Plasma Glucose Levels in Obese Children

OBJECTIVE

In this study, we aimed to investigate the association of W64R polymorphism of the β3-adrenergic receptor gene (β-3AR) with childhood obesity and related pathologies.

METHODS

β-3AR gene W64R genotyping was carried out in 251 children aged 6-18 years. Of these subjects, 130 were obese (62 boys) and 121 were normal-weight (53 boys). In the obese group, fasting lipids, glucose and insulin levels were measured. Oral glucose tolerance test (OGTT) was performed in 75 of the obese patients.

RESULTS

The frequency of W64R genotype was similar in obese and non-obese children. In obese children, relative body mass index, waist-to-hip ratio, serum lipid, glucose and insulin levels, as well as homeostasis model assessment of insulin resistance (HOMA-IR) scores were not different between Arg allele carriers (W64R and R64R) and noncarriers (W64W). In 75 obese children, OGTT results showed that Arg allele carriers had significantly higher 30-minute glucose levels (p=0.027).

CONCLUSION

W64R polymorphism of the β-3AR gene is not associated with obesity and waist-to-hip ratio in Turkish children. Although there were no relationships between the genotypes and lipid, glucose/insulin levels or HOMA-IR, the presence of W64R variant seemed to have an unfavorable influence on early glucose excursion after glucose loading.

Association between the Postprandial Glucose Levels and Arterial Stiffness Measured According to the Cardio-ankle Vascular Index in Non-diabetic Subjects

OBJECTIVE

Although a relationship between post-challenge hyperglycemia and arterial stiffness has been reported, the relationship between the postprandial glucose levels and cardio-ankle vascular index (CAVI) in non-diabetic subjects is not clear. This study thus evaluated the association between the postprandial glucose levels after a composite meal and the degree of arterial stiffness measured according to CAVI in non-diabetic subjects.

METHODS

The subjects included 1,291 individuals (655 men and 636 women; mean age, 48.6 years; range, 23-85 years) who underwent medical examinations, including blood tests and CAVI assessments, between October 2005 and April 2012. The 1-hour postprandial glucose levels were determined after a 600-kcal traditional Japanese meal.

RESULTS

The CAVI values were significantly higher in the subjects with higher 1-hour postprandial glucose levels (≥140 mg/dL in men; ≥158 mg/dL in women). A simple regression analysis indicated that the CAVI values were significantly correlated with the 1-hour postprandial glucose levels in men (r=0.286, p<0.0001) and women (r=0.228, p<0.0001). After adjusting for age, BMI, systolic blood pressure, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, 1-hour postprandial glucose, homeostatis model assessment of insulin resistance, estimated glemerular filtration rate, and high sensitive C-reactive protein, stepwise multiple regression analysis demonstrated that the 1-hour postprandial glucose level was an independent predictor associated with the CAVI in men (p=0.003) and older women 50 years of age or older (p=0.003).

CONCLUSION

This study demonstrated that the 1-hour postprandial glucose levels are associated with increased CAVI values in non-diabetic men and older women 50 years of age or older.

Urinary adiponectin concentration is positively associated with micro- and macro-vascular complications

BACKGROUND

A relationship between plasma adiponectin level and a number of metabolic conditions, including insulin resistance, obesity, and type 2 diabetes, has been reported. This study aimed to assess whether urinary adiponectin concentration is correlated with vascular complications.

METHODS

The study comprised 708 subjects who enrolled in the Seoul Metro City Diabetes Prevention Program and were carefully monitored from September 2008 to December 2008. Levels of urinary adiponectin were measured using an enzyme linked immunosorbent assay (ELISA) kit (AdipoGen, Korea). Urinary albumin excretion was assessed by the ratio of urinary albumin to creatinine (A/C ratio). Participants were divided into three groups based on tertiles of urinary adiponectin concentration, and we investigated whether urinary adiponectin levels are associated with microalbuminuria and pulse wave velocity.

RESULTS

Urinary adiponectin concentrations were significantly higher in subjects with microalbuminuria than subjects with normoalbuminuria (P < 0.001). Urinary adiponectin concentration was positively correlated with age, fasting plasma glucose level, HbA1C level, triglyceride level, HOMA-IR, systolic/diastolic blood pressure, and urinary A/C ratio (all P < 0.05). Subjects in the highest tertile of urinary adiponectin concentration had an increased likelihood of microalbuminuria than those in the lowest tertile (Odds ratio (OR), 6.437; 95% confidence interval (CI), 4.202 to 9.862; P < 0.001). After adjusting for age, sex, and estimated creatinine clearance rate (eCcr), the OR remained significant (OR, 5.607; 95% CI, 3.562 to 8.828; P < 0.001). Backward multiple linear regression analysis revealed urinary adiponectin concentration to be a significant determinant of mean brachial-ankle pulse wave velocity (baPWV).

CONCLUSIONS

An increased urinary adiponectin concentration is significantly associated with microalbuminuria and increased mean baPWV. These results suggest that urinary adiponectin may play an important role as a biomarker for vascular dysfunction.

Insulin Sensitivity and Beta-Cell Function Are Associated with Arterial Stiffness in Individuals without Hypertension

Aim. We investigated the relationship between brachial-ankle pulse wave velocity (baPWV) and glucose levels, insulin sensitivity, and beta-cell function in Chinese individuals with or without hypertension. Methods. We recruited 3137 nondiabetic individuals whose age, body mass index (BMI), glucose levels, blood pressure (BP), lipids, hemoglobin A1C (HbA1c), baPWV, and insulin levels were measured. Results. In normotensive group, 2 h glucose levels (β = 0.046, P < 0.001) associated with baPWV, showed a significant increase in patients with NG as compared to those with DM (P = 0.032). The hypertensive group showed no such differences. The Matsuda index (β = 0.114, P < 0.001) and HOMA- β (β = 0.045, P < 0.001) were negatively correlated with baPWV while lnHOMA-IR (β = 0.196, P = 0.076) and the Quantitative Insulin Sensitivity Check Index (QUICKI) (β = 0.226, P = 0.046) showed a borderline negative correlation. BaPWV significantly decreased (P = 0.032) with an increase in insulin sensitivity in individuals with both normal BP and glucose tolerance. Conclusions. BaPWV was significantly associated with 2 h glucose levels, insulin sensitivity and beta-cell function in normotensive population, whereas in hypertensive individuals, BP was the dominant factor influencing arterial stiffness. Individuals with abnormal insulin sensitivity in the absence of diabetes and hypertension are also at an increased risk of arterial stiffness.