The association between regional arterial stiffness and diabetic retinopathy in type 2 diabetes

Changes in carotid arterial wall viscosity and carotid arterial stiffness in type 2 diabetes patients

BACKGROUND AND AIMS

Changes in arterial wall viscosity (AWW) and stiffness during type 2 diabetes (T2D) have been little investigated. We explored changes in carotid AWV considering change in arterial stiffness and loading conditions, in patients with T2D.

METHODS

This cross-sectional, monocentric study compared 19 middle-aged patients with T2D to 30 non-diabetic (ND) controls. The absolute viscosity (WV) was determined as the area of the pressure-lumen cross-sectional area (P-LCSA) loop obtained by carotid tonometry and contralateral echo-tracking. The relative viscosity was determined as the ratio between WV and the elastic energy stored within the arterial wall (WV/WE). Carotid geometry, midwall stress, distensibility and elastic modulus were also compared between groups.

RESULTS

T2D patients were older and more frequently had hypertension. Internal diameter, mean central and pulse blood pressure were higher in T2D patients but midwall stress was similar compared to ND controls. WV and WV/WE were higher in T2D patients when compared with ND controls (23 [16-41] vs. 11 [7-18] mm Hg.mm2, p=0.007 and 21% [17-25] vs. 12% [8-17], p < 0.001 respectively) even after adjustment on confounding factors. Carotid arterial stiffness was higher in T2D patients, but after adjustment this difference was only observed for the highest levels of midwall stress.

CONCLUSIONS

Carotid AWV and stiffness are increased in T2D patients but only AWV is significantly increased after considering loading conditions. Whether this increase in energy dissipation within the arterial wall contributes to alter cardiovascular coupling in T2D remains to be established.

Increased Arterial Stiffness as a Predictor for Onset and Progression of Diabetic Retinopathy in Type 2 Diabetes Mellitus

INTRODUCTION

Brachial-ankle pulse wave velocity (baPWV), an indicator of arterial stiffness, has been demonstrated to be associated with type 2 diabetes mellitus (T2DM) and its vascular complications. This study was aimed at investigating the correlations of baPWV with both the presence and severity of diabetic retinopathy (DR) at baseline and at exploring the predictive role of baPWV in the new onset/progression of DR in the follow-up analysis.

METHODS

The prospective cohort study recruited 2,473 Chinese patients with T2DM, of whom 663 participants were finally included in the follow-up analysis. The presence and grading of DR were performed by the modified Early Treatment Diabetic Retinopathy Study. Uni- or multivariate linear and logistic regression models and Cox proportional-hazards regression analysis were conducted.

RESULTS

Of 2,473 patients with T2DM at baseline, 734 individuals were assessed to have DR and further categorized into 630 with non-sight-threatening DR (NSTDR) and 104 with STDR. In addition to the positive relationship between increased baPWV and the presence of DR, multinominal logistic regression analysis revealed that higher tertiles of baPWV were significantly related to the NSTDR (T2: OR = 1.62 (1.22, 2.15), p < 0.001, and T3: OR = 2.58 (1.86, 3.58), p < 0.001) and STDR group (T3: OR = 3.87 (1.87, 8.02), p < 0.001). During a follow-up (mean period of 16.4 months), 111 participants had new onset/progression of DR. The cox regressions showed that high baseline baPWV was correlated with increased risk of development/progression of DR (HR = 2.24, 95% CI (1.24, 4.03), p = 0.007, for T2 baPWV and HR = 2.90, 95% CI (1.49, 5.64), p = 0.002, for T3 baPWV) after adjustments for multiple factors.

CONCLUSIONS

Our results demonstrated that baseline baPWV might be an independent predictor in new onset/worsening of DR, suggesting that increased arterial stiffness might be involved in the development of DR. Follow-up studies with a longer duration are needed.

Stronger association of triglyceride glucose index than the HOMA-IR with arterial stiffness in patients with type 2 diabetes: a real-world single-centre study

Background

The triglyceride-glucose index (TyG index) has been proposed as a simple and reliable alternative insulin resistance (IR) marker, while the homeostasis model assessment for IR (HOMA-IR) is the most frequently used index. Few studies have evaluated the role of IR assessed by the TyG index and HOMA-IR on arterial stiffness in a type 2 diabetes (T2D) population with a high risk of increased arterial stiffness. We aimed to investigate the association of the TyG index and HOMA-IR with arterial stiffness in patients with T2D.

Methods

We recruited 3185 patients with T2D, who underwent brachial-ankle pulse wave velocity (baPWV), an indicator of arterial stiffness, but without previous cardiovascular disease. Increased arterial stiffness was defined as a baPWV value greater than the 75th percentile (18.15 m/s) in the present study. The TyG index was determined as ln(fasting triglycerides [mg/dL] × fasting glucose [mg/dL]/2), and the HOMA-IR was calculated as (fasting insulin [μIU/mL] × fasting glucose [mmol/L])/22.5.

Results

The mean age of the study participants was 54.6 ± 12.0 years, and 1954 (61.4%) were men. Seemingly unrelated regression estimation analysis demonstrated that the TyG index had stronger associations with baPWV than the HOMA-IR (all P < 0.001). In the multivariable logistic analyses, each one-unit increase in the TyG index was associated with a 1.40-fold (95% CI 1.16–1.70, P < 0.001) higher prevalence of increased arterial stiffness, but the prominent association of the HOMA-IR with the prevalence of increased arterial stiffness was not observed. Subgroup analyses showed that a more significant association between the TyG index and the prevalence of increased arterial stiffness was detected in older patients with a longer duration of diabetes and poor glycaemic control (all P < 0.05).

Conclusions

Compared with the HOMA-IR, the TyG index is independently and more strongly associated with arterial stiffness in patients with T2D.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01274-x.

High pulse wave velocity is associated with the severity of diabetic retinopathy in patients with type 2 diabetes

Pulse wave velocity (PWV) is a non-invasive test for assessing arterial stiffness, and brachial-ankle PWV has been used as an index of peripheral arterial stiffness. This study aimed to investigate the association between the PWV value and severity of diabetic retinopathy (DR). 846 patients with type 2 diabetes (T2DM) consecutively underwent brachial-ankle PWV, and the degree of PWV was defined by tertile. The severity of DR was categorized as no diabetic retinopathy (NDR), non-proliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR) based on the Early Treatment Diabetic Retinopathy Study Scale. Multinomial logistic regression analyses were utilized not only to explore the association between the degree of PWV and severity of DR but also to examine the association of a high-tertile PWV with PDR. PWV levels, diabetes duration and blood pressure were all significantly higher in subjects with NPDR or PDR as compared with individuals with NDR. In the univariate analysis, the highest tertile of PWV (>19.6 m/s) was significantly associated with both NPDR (p<0.001) and PDR (p<0.001) as compared with NDR. After adjusting for confounding factors, the highest tertile of PWV remained significantly associated with PDR (p=0.005), but not with NPDR (p=0.107). Furthermore, the highest tertile of PWV was more significantly associated with PDR (OR=6.15, 95%CI 1.38 to 27.38) as compared with the lowest tertile. In our study, an increasing degree of PWV was positively associated with the severity of DR. High PWV was strongly associated with the risk of severe DR, especially PDR.

Predictors for progressions of brachial-ankle pulse wave velocity and carotid intima-media thickness over a 12-year follow-up: Hanzhong Adolescent Hypertension Study

Objective:

Atherosclerotic diseases are the leading cause of death worldwide. This study aimed to investigate the predictors of brachial–ankle pulse wave velocity (baPWV) and carotid intima–media thickness (CIMT) progression in a Chinese cohort over a 12-year follow-up period and to determine whether these predictors differ by follow-up time.

Methods:

A total of 202 participants were recruited from a previously established cohort in Shaanxi Province, China. Both baPWV and CIMT were measured in 2013 and 2017. Multivariable regression was used to determine the predictors of CIMT and baPWV progression.

Results:

Men had higher CIMT and baPWV and a higher rate of CIMT progression during two follow-ups than women. A 4-year change in SBP was associated with baPWV progression, whereas a 12-year change in DBP was associated with baPWV progression. The increased progression of baPWV presented a linear trend when subgrouping all the participants according to SBP and DBP changes over 4 and 12 years, respectively. In addition, heart rate (HR) change over 4 and 12 years was consistently associated with CIMT progression, and a linear trend was also seen when subgrouping the population.

Conclusion:

Our study demonstrated that SBP and DBP contributed differently in different stages to the progression of arterial stiffness in this Chinese cohort. Moreover, HR was consistently involved in the increased progression of CIMT in all periods. These findings underline the importance of early detection and control of blood pressure and resting HR for the prevention of arterial stiffness progression.

Central arterial stiffness and retinal vessel calibers: the Atherosclerosis Risk in Communities Study-Neurocognitive Study

BACKGROUND

The retinal microvasculature provides a window to the cerebral vasculature and enables examination of changes in retinal caliber that may mimic those occurring in cerebrovascular disease. The association of central arterial stiffness and retinal vessel caliber in a population sample is not fully understood.

METHODS

In 1706 older adults (mean age 76.3, 58.1% women) from the population-based Atherosclerosis Risk in Communities Study, we examined the cross-sectional association of central arterial stiffness [carotid-femoral pulse wave velocity (cfPWV)] with retinal vessel calibers [central retinal arteriolar equivalent (CRAE) and central retinal vein equivalent (CRVE)]. We estimated the association of cfPWV with CRAE narrowing (<25th percentile) and CRVE widening (>75th percentile) after adjustment for age, sex, race-field center, BMI, smoking, and type 2 diabetes. We tested for effect modification by sex, hypertension, and type 2 diabetes.

RESULTS

Carotid-femoral PWV (m/s) was not associated with the odds of CRAE narrowing [odds ratio (OR): 0.99; 95% CI: 0.95-1.03]. The association of cfPWV with CRVE widening was stronger in those without hypertension (OR: 1.10; 95% CI: 1.01-1.20) versus those with hypertension (OR: 1.01 95% CI: 0.96-1.05) and slightly stronger in those with type 2 diabetes (OR: 1.07; 95% CI: 1.00-1.14) versus without type 2 diabetes (OR: 1.01; 95% CI: 0.96-1.06).

CONCLUSIONS

In older adults, cfPWV was associated with wider retinal venular caliber, particularly in individuals without hypertension. Central arterial stiffening may be associated with cerebral microvascular changes, as exhibited in its retinal vasculature component.

From Endothelial Dysfunction to Arterial Stiffness in Diabetes Mellitus

Prevalence of diabetes mellitus has increased drastically over time, especially in more populous countries such as the United States, India, and China. Patients with diabetes have an increased risk of major cardiovascular events such as acute myocardial infarction, cerebrovascular disease, and peripheral vascular disease. Arterial stiffness is a process related to aging and vascular, metabolic, cellular and physiological deterioration. In recent years, it has been described as an independent predictor of cardiovascular mortality and coronary artery disease. Additionally, it plays an important role in the measurement of chronic disease progression. Recent studies have suggested a strong relationship between diabetes mellitus and arterial stiffness since they share a similar pathophysiology involving endothelial dysfunction. The literature has shown that microvascular and macrovascular complications in diabetic patients could be screened and measured with arterial stiffness. Additionally, new evidence proposes that there is a relationship between blood glucose levels, microalbuminuria, and arterial stiffness. Moreover, arterial stiffness predicts cardiovascular risk and is independently associated with mortality in diabetic patients. Abnormal arterial stiffness values in diabetic patients should alert the clinician to the presence of vascular disease, which merits early study and treatment. We await more studies to determine if arterial stiffness could be considered a routine useful non-invasive tool in the evaluation of diabetic patients. There is enough evidence to conclude that arterial stiffness is related to the progression of diabetes mellitus.

Association of central arterial stiffness with the presence and severity of diabetic retinopathy in Asians with type 2 diabetes

OBJECTIVE

Arterial stiffness has been associated with diabetic retinopathy; however, the information is limited in Asians. We aim to examine the association of central arterial stiffness with the presence and severity of diabetic retinopathy in type 2 diabetes mellitus patients in Singapore.

METHODS

Arterial stiffness was estimated by carotid-femoral pulse wave velocity and augmentation index using applanation tonometry method. Digital colour fundus photographs from 1,203 patients were assessed for diabetic retinopathy. Diabetic retinopathy severity was categorized into non-proliferative diabetic retinopathy and proliferative diabetic retinopathy. Logistic regression model was used to evaluate the associations of diabetic retinopathy with pulse wave velocity and augmentation index.

RESULTS

Diabetic retinopathy was diagnosed in 391 (32.5%) patients, including 271 non-proliferative diabetic retinopathy and 108 proliferative diabetic retinopathy. Diabetic retinopathy have higher pulse wave velocity (11.2 ± 3.3 vs 9.5 ± 2.6 m/s, p < 0.001) and augmentation index (28.4 ± 9.4 vs 26.1 ± 10.6%, p < 0.001) than non-diabetic retinopathy. After multivariable adjustment, pulse wave velocity [odds ratio = 1.11 (95% confidence interval = 1.05-1.17), p < 0.001] and augmentation index [odds ratio = 1.03 (95% confidence interval = 1.01-1.04), p = 0.009] was associated with diabetic retinopathy. In severity analyses, pulse wave velocity was associated with non-proliferative diabetic retinopathy [odds ratio = 1.10 (95% confidence interval = 1.03-1.17), p = 0.002] and proliferative diabetic retinopathy [odds ratio = 1.15 (95% confidence interval = 1.06-1.25), p = 0.001] (p-trend < 0.001). Augmentation index showed significant associations with non-proliferative diabetic retinopathy [odds ratio = 1.02 (95% confidence interval = 1.01-1.04), p = 0.008], but not with proliferative diabetic retinopathy [odds ratio = 1.01 (95% confidence interval = 0.98-1.04), p = 0.36] (p-trend = 0.03).

CONCLUSION

Central arterial stiffness was associated with the presence and severity of diabetic retinopathy in type 2 diabetes mellitus patients, suggesting its etiologic implication in diabetic retinopathy.

Arterial Stiffness Assessed by Cardio-Ankle Vascular Index

Arterial stiffness is an age-related disorder. In the medial layer of arteries, mechanical fracture due to fatigue failure for the pulsatile wall strain causes medial degeneration vascular remodeling. The alteration of extracellular matrix composition and arterial geometry result in structural arterial stiffness. Calcium deposition and other factors such as advanced glycation end product-mediated collagen cross-linking aggravate the structural arterial stiffness. On the other hand, endothelial dysfunction is a cause of arterial stiffness. The biological molecular mechanisms relating to aging are known to involve the progression of arterial stiffness. Arterial stiffness further applies stress on large arteries and also microcirculation. Therefore, it is closely related to adverse outcomes in cardiovascular and cerebrovascular system. Cardio-ankle vascular index (CAVI) is a promising diagnostic tool for evaluating arterial stiffness. The principle is based on stiffness parameter β, which is an index intended to assess the distensibility of carotid artery. Stiffness parameter β is a two-dimensional technique obtained from changes of arterial diameter by pulse in one section. CAVI applied the stiffness parameter β to all of the arterial segments between heart and ankle using pulse wave velocity. CAVI has been commercially available for a decade and the clinical data of its effectiveness has accumulated. The characteristics of CAVI differ from other physiological tests of arterial stiffness due to the independency from blood pressure at the time of examination. This review describes the pathophysiology of arterial stiffness and CAVI. Molecular mechanisms will also be covered.

Impact of Diabetes Mellitus on Ventricular Structure, Arterial Stiffness, and Pulsatile Hemodynamics in Heart Failure With Preserved Ejection Fraction

Background Heterogeneity in the underlying processes that contribute to heart failure with preserved ejection fraction ( HF p EF ) is increasingly recognized. Diabetes mellitus is a frequent comorbidity in HF p EF , but its impact on left ventricular and arterial structure and function in HF p EF is unknown. Methods and Results We assessed the impact of diabetes mellitus on left ventricular cellular and interstitial hypertrophy (assessed with cardiac magnetic resonance imaging, including T1 mapping pregadolinium and postgadolinium administration), arterial stiffness (assessed with arterial tonometry), and pulsatile arterial hemodynamics (assessed with in-office pressure-flow analyses and 24-hour ambulatory monitoring) among 53 subjects with HF p EF (32 diabetic and 21 nondiabetic subjects). Despite few differences in clinical characteristics, diabetic subjects with HFpEF exhibited a markedly greater left ventricular mass index (78.1 [95% CI , 70.4-85.9] g versus 63.6 [95% CI , 55.8-71.3] g; P=0.0093) and indexed extracellular volume (23.6 [95% CI , 21.2-26.1] mL/m2 versus 16.2 [95% CI , 13.1-19.4] mL/m2; P=0.0008). Pronounced aortic stiffening was also observed in the diabetic group (carotid-femoral pulse wave velocity, 11.86 [95% CI , 10.4-13.1] m/s versus 8.8 [95% CI , 7.5-10.1] m/s; P=0.0027), with an adverse pulsatile hemodynamic profile characterized by increased oscillatory power (315 [95% CI , 258-373] mW versus 190 [95% CI , 144-236] mW; P=0.0007), aortic characteristic impedance (0.154 [95% CI , 0.124-0.183] mm Hg/mL per second versus 0.096 [95% CI , 0.072-0.121] mm Hg/mL per second; P=0.0024), and forward (59.5 [95% CI , 52.8-66.1] mm Hg versus 40.1 [95% CI , 31.6-48.6] mm Hg; P=0.0010) and backward (19.6 [95% CI , 16.2-22.9] mm Hg versus 14.1 [95% CI , 10.9-17.3] mm Hg; P=0.0169) wave amplitude. Abnormal pulsatile hemodynamics were also evident in 24-hour ambulatory monitoring, despite the absence of significant differences in 24-hour systolic blood pressure between the groups. Conclusions Diabetes mellitus is a key determinant of left ventricular remodeling, arterial stiffness, adverse pulsatile hemodynamics, and ventricular-arterial interactions in HF p EF . Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifier: NCT 01516346.

Correlation of systemic arterial stiffness with changes in retinal and choroidal microvasculature in type 2 diabetes

This study was conducted to assess whether systemic arterial stiffness, indicated by cardio-ankle vascular index (CAVI), is related to changes in the microvasculature of the retina and choroid in diabetes mellitus (DM). This study included 113 patients with a confirmed diagnosis of type-2 DM. Among them, 18 patients did not have diabetic retinopathy (DR), 71 had non-proliferative DR (NPDR), and 24 had proliferative DR (PDR). The mean CAVI was 7.58 ± 1.41 in no DR, 8.72 ± 1.47 in NPDR, and 8.43 ± 1.25 in PDR group. Of the 113 eyes, 42 (37.2%) were classified as abnormal CAVI group (CAVI ≥ 9). This group had significantly higher cardiac autonomic neuropathy risk index score, decreased central choroidal thickness, and decreased choroidal vascularity index (CVI). Deep foveal avascular zone area was higher in the abnormal CAVI group. After adjustment for possible confounding factors, CAVI showed negative correlation with the CVI (r = -0.247, P = 0.013). In conclusion, there was a significant correlation between arteriosclerosis and choroidal vascular changes in DR. We suggest prompt ophthalmic evaluation in patients with systemic arteriosclerosis. If the ophthalmologist notes advanced DR, the patient should be referred to a cardiovascular clinic for detailed evaluation of systemic arteriosclerosis.

Relationship of Selected Adipokines with Markers of Vascular Damage in Patients with Type 2 Diabetes

BACKGROUND

In this study we compared levels of selected adipokines between patients with type 2 diabetes (T2D) and healthy individuals and we determined their relationship with early vascular damage markers.

METHODS

Seventy-seven subjects: 56 patients with T2D (34 men and 22 women) and 21 healthy controls (8 men and 13 women) were examined in this cross-sectional study. Selected adipokines [adiponectin, adipocyte fatty acid-binding protein (A-FABP), fibroblast growth factor 21 (FGF-21), C1q/TNF-related protein 9 (CTRP-9), and allograft inflammatory factor-1 (AIF-1)] with possible cardiovascular impact were measured in all participants. To identify markers of vascular damage von Willebrand factor (vWF), plasminogen activator inhibitor-1 (PAI-1) and arterial stiffness parameters were examined in all the subjects.

RESULTS

When compared with healthy controls, T2D had significantly higher levels of A-FABP [50.0 (38.1-68.6) vs. 28.6 (23.6-32.9) ng/mL, P < 0.0001] and lower levels of adiponectin [5.9 (4.3-9.0) vs. 11.3 (8.7-14.8) μg/mL, P < 0.0001]. Differences in other adipokines were not statistically significant. Adiponectin level correlated negatively with vWF levels (ρ = -0.29, P < 0.05) and PAI-1 (ρ = -0.36, P < 0.05) and A-FABP positively with vWF (ρ = 0.61, P < 0.05) and PAI-1 (ρ = 0.47, P < 0.05) and augmentation index (ρ = 0.26, P < 0.05). Multivariate regression analysis showed independent association between A-FABP and vWF (b = 0.24, P < 0.05).

CONCLUSIONS

Patients with T2D have significantly higher levels of A-FABP and lower levels of adiponectin. These adipokines correlate with indicators of vascular damage and could contribute to cardiovascular risk in patients with T2D. A-FABP may participate in direct endothelium damage.

Acute impact of drinking coffee on the cerebral and systemic vasculature

Previous studies have suggested that the risk of ischemic stroke increases immediately after drinking coffee. Indeed, drinking coffee, that is, caffeine, acutely increases arterial stiffness as well as blood pressure and peripheral vascular resistance. On the other hand, it has been reported that arterial stiffening is associated with elevation in the pulsatility index (PI) of cerebral blood flow (CBF), which increases the risk of brain disease. However, the effect of drinking coffee on the PI of the CBF and its interaction with arterial stiffness remain unknown. Against this background, we hypothesized that an acute increase in arterial stiffness induced by drinking coffee augments cerebral pulsatile stress. To test this hypothesis, in 10 healthy young men we examined the effects of drinking coffee on the PI of middle cerebral artery blood velocity (MCAv) and brachial‐ankle pulse wave velocity (baPWV) as indices of cerebral pulsatile stress and arterial stiffness, respectively. Mean arterial blood pressure and baPWV were higher (P < 0.01 and P = 0.02), whereas mean MCA_V and mean cerebrovascular conductance index were lower upon drinking coffee (P = 0.02 and P < 0.01) compared with a placebo (decaffeinated coffee). However, there was no difference in the PI of MCAv between drinking coffee and the placebo condition. These findings suggest that drinking coffee does not increase cerebral pulsatile stress acutely despite an elevation in arterial stiffness in the systemic circulation.

Arterial stiffness is an independent predictor for albuminuria progression among Asians with type 2 diabetes-A prospective cohort study

AIM

Albuminuria progression has been associated with renal deterioration in type 2 diabetes (T2DM). Central arterial stiffness can aggravate systemic vasculopathy by propagating elevated systolic and pulse pressures forward, thereby accentuating global vascular injury. We aim to investigate whether central arterial stiffness is an independent predictor for albuminuria progression in a multi-ethnic T2DM Asian cohort in Singapore.

METHODS

In a prospective cohort, 1012 T2DM patients were assessed at baseline and after a median follow-up of 3.1years. 880 patients with baseline normo- (urinary albumin-to-creatinine ratio (ACR)<30mg/g, n=579) and microalbuminuria (ACR=30-299mg/g, n=301) were divided into progression and non-progression groups according to ACR changes. Progression was defined as transition from normo- to microalbuminuria, micro- to macroalbuminuria, or normo- to macroalbuminuria. Central arterial stiffness was estimated by carotid-femoral pulse wave velocity (PWV) using applanation tonometry method. Stepwise multiple regression analysis was used to determine the predictor(s) for albuminuria progression.

RESULTS

Albuminuria progression occurred in 178 patients (20.2%). Baseline PWV was higher in progression (10.1±2.9m/s) than non-progression group (9.2±2.4m/s, p<0.001). 1-SD increase in baseline PWV was associated with albuminuria progression (OR=1.457, 95% CI, 1.236-1.718, p<0.001). Stepwise regression analysis identified that baseline PWV (OR=1.241, 95% CI, 1.033-1.490, p=0.021), BMI (OR=1.046, 95% CI, 1.012-1.080, p=0.008), nature log-transformed estimated glomerular filtration rate (LneGFR) (OR=0.320, 95% CI, 0.192-0.530, p=0.010) and LnACR (OR=1.344, 95% CI, 1.187-1.522, p=0.008) are predictors for albuminuria progression.

CONCLUSION

Increased central arterial stiffness at baseline predicted future progression of albuminuria. Our results suggest the potential benefit of ameliorating central arterial stiffness to retard albuminuria progression in T2DM.

Inactive Matrix Gla-Protein and Arterial Stiffness in Type 2 Diabetes Mellitus

BACKGROUND

Large artery stiffness is increased in diabetes mellitus and causes an excessive pulsatile load to the heart and to the microvasculature. The identification of pathways related to arterial stiffness may provide novel therapeutic targets to ameliorate arterial stiffness in diabetes. Matrix Gla-Protein (MGP) is an inhibitor of vascular calcification. Activation of MGP is vitamin K dependent. We hypothesized that levels of inactive MGP (dephospho-uncarboxylated MGP; dp-ucMGP) are related to arterial stiffness in type 2 diabetes.

METHODS

We enrolled a multiethnic cohort of 66 participants with type 2 diabetes. Carotid-femoral pulse wave velocity (CF-PWV) was measured with high-fidelity arterial tonometry (Sphygmocor Device). Dp-ucMGP was measured with ELISA (VitaK; The Netherlands).

RESULTS

The majority of the participants were middle-aged (62 ± 12 years), male (91%), and had a history of hypertension (82%). Average hemoglobin A1C was 7.2% (55 mmol/mol). Mean dp-ucMGP was 624 ± 638 pmol/l and mean CF-PWV was 11 ± 4 m/sec. In multivariable analyses, dp-ucMGP was independently related to African American ethnicity (β = -0.24, P = 0.005), warfarin use (β = 0.56, P < 0.001), and estimated glomerular filtration rate (eGFR, β = -0.32, P < 0.001). Dp-ucMGP predicted CF-PWV (β = 0.40, P = 0.011), even after adjustment for age, gender, ethnicity, mean arterial pressure, eGFR, and warfarin use.

CONCLUSIONS

In our cross-sectional analysis, circulating dp-ucMGP was independently associated with CF-PWV in type 2 diabetes. This suggests that deficient vitamin K-dependent activation of MGP may lead to large artery stiffening and could be targeted with vitamin K supplementation in the patients with diabetes.

Aortic Stiffness as a Surrogate Endpoint to Micro- and Macrovascular Complications in Patients with Type 2 Diabetes

Increased aortic stiffness has been recognized as a predictor of adverse cardiovascular outcomes in some clinical conditions, such as in patients with arterial hypertension and end-stage renal disease, in population-based samples and, more recently, in type 2 diabetic patients. Patients with type 2 diabetes have higher aortic stiffness than non-diabetic individuals, and increased aortic stiffness has been correlated to the presence of micro- and macrovascular chronic diabetic complications. We aimed to review the current knowledge on the relationships between aortic stiffness and diabetic complications, their possible underlying physiopathological mechanisms, and their potential applications to clinical type 2 diabetes management.

Correlation of retinal arterial wall thickness with atherosclerosis predictors in type 2 diabetes without clinical retinopathy

AIMS

To evaluate retinal arterial wall thickness (WT) using high-resolution retinal imaging in patients with type 2 diabetes and assess its correlation with risk factors for arteriosclerosis.

METHODS

Outer diameter, inner diameter and WT of the retinal artery were measured using adaptive optics scanning laser ophthalmoscopy in 28 patients with type 2 diabetes without clinically apparent diabetic retinopathy and normal volunteers. Laboratory values and intima-media thickness (IMT) in the common carotid artery were measured.

RESULTS

Retinal arterial WT was significantly greater in patients with type 2 diabetes than in controls (p=0.02). There was a significant correlation of retinal artery WT with IMT in patients with diabetes (r=0.40, p=0.04). WT in patients with diabetes was positively correlated with haemoglobin A1c (HbA1c) (r=0.49, p=0.001), total cholesterol (r=0.47, p=0.002) and low-density lipoprotein cholesterol (r=0.47, p=0.003).

CONCLUSIONS

Microvasuclar thickness was greater in patients with diabetes than in controls. Furthermore, WT was positively correlated with HbA1c, total cholesterol and low-density lipoprotein cholesterol levels and IMT in the diabetic group. These results suggest that retinal artery wall measurements can be potential surrogate markers of early diabetic microangiopathy.

Unequal Arterial Stiffness With Overall and Cardiovascular Mortality in Patients Receiving Hemodialysis

BACKGROUND

Pulse wave velocity is a marker of arterial stiffness. Unequal arterial stiffness has been associated with increased risk of cardiovascular events. This study calculated bilateral brachial-ankle pulse wave velocity (baPWV) differences and investigated the associations of unequal bilateral baPWV with overall and cardiovascular mortality in patients receiving hemodialysis (HD).

MATERIALS AND METHODS

A total of 205 patients receiving HD were enrolled in this study. The mean follow-up period was 4.4 ± 1.5 years. The baPWV was measured using an ankle-brachial index-form device, and bilateral baPWV difference was calculated and defined as ΔbaPWV.

RESULTS

The median value of ΔbaPWV was 88cm/second. ankle-brachial index < 0.95 and high baPWV were independently associated with a ΔbaPWV ≥ 88cm/s. Furthermore, patients with a ΔbaPWV ≥ 88cm/s demonstrated poorer overall (log-rank P = 0.035) and cardiovascular (log-rank P = 0.036) survival than did those with a ΔbaPWV < 88cm/s. After multivariate analysis, this difference was independently associated with overall (hazard ratio = 1.006; 95% CI: 1.001-1.011; P = 0.024) and cardiovascular (hazard ratio = 1.006; 95% CI: 1.000-1.013; P = 0.049) mortality.

CONCLUSIONS

ΔbaPWV was associated with an increased risk of cardiovascular and overall mortality in patients receiving HD. Earlier evaluation of ΔbaPWV may facilitate the identification of patients receiving HD who have an increased risk of cardiovascular and overall mortality.

Arterial Stiffness in Nonhypertensive Type 2 Diabetes Patients in Ghana

Background. Increased arterial stiffness is an independent cardiovascular risk factor in diabetes patients and general population. However, the contribution of diabetes to arterial stiffness is often masked by coexistent obesity and hypertension. In this study, we assessed arterial stiffness in nonhypertensive, nonobese type 2 diabetes (T2DM) patients in Ghana. Methods. In case-control design, 166 nonhypertensive, nonobese participants, comprising 96 T2DM patients and 70 nondiabetes controls, were recruited. Peripheral and central blood pressure (BP) indices were measured, and arterial stiffness was assessed as aortic pulse wave velocity (PWVao), augmentation index (AIx), cardioankle vascular index (CAVI), and heart-ankle pulse wave velocity (haPWV). Results. With similar peripheral and central BP indices, T2DM patients had higher PWVao (8.3 ± 1 versus 7.8 ± 1.3, p = 0.044) and CAVI (7.9 ± 1.2 versus 6.9 ± 0.7, p = 0.021) than nondiabetic control. AIx and haPWV were similar between T2DM and nondiabetic controls. Multiple regression models showed that, in the entire study participants, the major determinants of PWVao were diabetes status, age, gender, systolic BP, and previous smoking status (β = 0.22, 0.36, 0.48, 0.21, and 0.25, resp.; all p < 0.05); the determinants of CAVI were diabetes status, age, BMI, heart rate, HbA1c, total cholesterol, HDL cholesterol, and previous smoking status (β = 0.21, 0.38, 0.2, 0.18, 0.24. 0.2, -0.19, and 0.2, resp.; all p < 0.05). Conclusion. Our findings suggest that nonhypertensive, nonobese T2DM patients have increased arterial stiffness without appreciable increase in peripheral and central pressure indices.

Ankle-brachial index and inter-artery blood pressure differences as predictors of cognitive function in overweight and obese older adults with diabetes: results from the Action for Health in Diabetes movement and memory study

OBJECTIVE

Ankle-brachial index (ABI) and interartery systolic blood pressure differences, as markers of vascular disease, are plausible risk factors for deficits in cognitive function among overweight and obese adults with type 2 diabetes.

METHODS

The ABI and maximum interartery differences (MIAD) in systolic blood pressures were assessed annually for five years among 479 participants assigned to the control condition in a randomized clinical trial of a behavioral weight loss intervention. A battery of standardized cognitive function tests was administered 4 to 5 years later. Analyses of covariance were used to assess relationships that ABI, MIAD, and progression of ABI and MIAD had with cognitive function.

RESULTS

There was a curvilinear relationship between ABI and a composite index of cognitive function (p = 0.03), with lower ABI being associated with poorer function. In graded fashions, both greater MIAD and increases in MIAD over time also had modest relationships with poorer verbal memory (both p ≤ 0.05), processing speed (both p ≤ 0.05), and composite cognitive function (both p < 0.04). These relationships were independent of each other and remained evident after extensive covariate adjustment.

CONCLUSIONS

In overweight and obese adults with type 2 diabetes, lower ABI and larger interartery systolic blood pressure differences have modest, independent, graded relationships with poorer cognitive function 4-5 years later.

Determinants of arterial stiffness progression in a Han-Chinese population in Taiwan: a 4-year longitudinal follow-up

Background

Arterial stiffness predicts the future risk of macro- and micro-vascular diseases. Only a few studies have reported longitudinal changes. The present study aimed to investigate the progression rate of arterial stiffness and the factors influencing stiffness progression in a Han Chinese population residing in Taiwan.

Methods

The pulse wave velocity (PWV), elasticity modulus (Ep) and arterial stiffness index (β) of the common carotid artery were measured in 577 stroke- and myocardial infarction-free subjects at baseline and after an average interval of 4.2 ± 0.8 years. Stepwise multivariate linear regression was conducted to elucidate the predictors of stiffness progression.

Results

For both baseline and follow-up data, men had significantly higher values of PWV, Ep and β in comparison to women. The progression rates of PWV, Ep and β were faster in men, but the difference was not statistically significant (ΔPWV = 0.20 ± 0.20 and 0.18 ± 0.20 m/s/yr; ΔEp = 8.17 ± 8.65 and 6.98 ± 8.26 kPa/yr; Δβ = 0.70 ± 0.64 and 0.67 ± 0.56 for men and women, respectively). In the multivariate regression analyses, age, baseline stiffness parameters, baseline mean arterial pressure (MAP), baseline body mass index (BMI) and changes in MAP (ΔMAP) were independent predictors of PWV and Ep progression. There was an inverse correlation between the stiffness parameters at baseline and their progression rate (correlation coefficient (r) = −0.12 to −0.33, p = 0.032–1.6 × 10⁻¹⁶). Changes in MAP (ΔMAP) rather than baseline MAP were more strongly associated with PWV progression (p = 8.5 × 10⁻²⁴ and 1.9 × 10⁻⁵ for ΔMAP and baseline MAP, respectively). Sex-specific analyses disclosed that baseline BMI and changes in BMI (ΔBMI) were significantly associated with stiffness progression in men (p = 0.010–0.026), but not in women.

Conclusions

Aging and elevated blood pressure at baseline and during follow-up were the major determinants of stiffness progression in the Han Chinese population. For men, increased baseline BMI and changes in BMI were additional risk factors.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-015-0093-2) contains supplementary material, which is available to authorized users.

Impact of short-term training camp on arterial stiffness in endurance runners

Lack of elasticity in the central artery causes an increase in left ventricular (LV) afterload. Although regular moderate-intensity endurance exercise improves cardiovascular function, including arterial destiffening, little is known about the effect of short-term vigorous exercise on cardiovascular function (i.e., the interaction between cardiac and arterial functions). We measured arterial stiffness [via pulse wave velocity from the heart to ankle (haPWV)] and LV contractility (via systolic interval time) before and after a 1-week training camp in a total of 33 regularly highly-trained collegiate endurance runners. They participated in three training sessions per day which mainly consisted of long-distance running and sprint training. The averaged running distance was ≈ 44% longer during the camp than the regular training program. After the camp, heart rate at rest and haPWV were significantly increased, whereas blood pressure remained unchanged. Although a ratio of pre-ejection period and LV ejection time (PEP/LVET, an index of blunted LV contractility) was unaltered, presumably due to the large variability of individual response, there was a significant correlation between changes in haPWV and PEP/LVET (r = 0.54, P < 0.01). These results suggest that, in regularly highly-trained endurance athletes, arterial stiffness increases after a training camp characterized by greater training volume (vs. regular training), and that the individual response in arterial stiffness correlates with the corresponding changes in myocardial contractility.

Prognostic Significance of Regional Arterial Stiffness for Stroke in Hypertension

BACKGROUND

Hypertension is strongly associated with cardiovascular disease. It has been reported that arterial stiffness is related to cardiovascular mortality and morbidity in hypertensive patients and that the physiological evaluation of arterial stiffness may assist clinicians in the early detection of atherosclerosis.

SUMMARY

It has been demonstrated that increased arterial stiffness is an independent predictor of cardiovascular disease, including stroke. Arterial stiffness is associated with structural changes in the brain. However, the stiffness responses of muscular arteries are different from those of elastic arteries, and so the impact of arterial stiffness and the conclusions to be drawn may be different depending on the region in which the measurement is taken.

KEY MESSAGES

In this review, we summarize the current literature describing the association between arterial stiffness, including carotid-femoral and brachial-ankle pulse wave velocity and cardio-ankle vascular index, and cardiovascular disease, specifically stroke. We discuss the utility and prognostic significance of regional arterial stiffness measurements.

Association between diabetic retinopathy and subclinical atherosclerosis in China: Results from a community-based study

PURPOSE

To evaluate the association of diabetic retinopathy with subclinical atherosclerosis in middle-aged and elderly Chinese with type 2 diabetes.

METHODS

A cross-sectional community-based study was performed among 1607 patients aged 40 years or older in Shanghai. Non-mydriatic digital fundus photography examination was used in diabetic retinopathy detection. Presence of elevated carotid intima-media thickness or carotid plaque was defined as subclinical atherosclerosis.

RESULTS

The prevalence of diabetic retinopathy was 15.1% in total patients. Patients with diabetic retinopathy were more likely to have elevated carotid intima-media thickness, carotid plaque and subclinical atherosclerosis than those without diabetic retinopathy (37.9% vs 30.7%, 57.6% vs 49.6% and 64.6% vs 57.1%, respectively). The presence of diabetic retinopathy was significantly associated with increased odds of subclinical atherosclerosis (odds ratio = 1.93, 95% confidence interval = 1.03-3.60) after full adjustments.

CONCLUSION

The presence of diabetic retinopathy was significantly associated with subclinical atherosclerosis in middle-aged and elderly patients with type 2 diabetics in China.

Association between urinary 8-OHdG and pulse wave velocity in hypertensive patients with type 2 diabetes mellitus

INTRODUCTION

Oxidative stress, assessed using 8-hydroxy-2'-deoxyguanosine (8-OHdG), can be associated with arterial stiffness in patients with type 2 diabetes mellitus (T2DM) and/or hypertension (HT). We investigated the correlation between urinary 8-OHdG and pulse wave velocity (PWV) in hypertensive and non-hypertensive T2DM patients with fair glycaemic control to determine the clinical significance of HT as a comorbidity in the diabetic state.

METHODS

Clinical data, including traditional cardiovascular risk factors, diabetic complications, prescribed agents, urinary 8-OHdG level and brachial-ankle PWV, was collected from T2DM patients with and without HT.

RESULTS

There were 76 patients (45 men, 31 women; mean age 61 years; mean haemoglobin A1c level 6.5%) in the study cohort. T2DM patients with HT had significantly higher mean PWV than patients without HT (1,597 cm/s vs 1,442 cm/s; p < 0.05). Patients with HT showed no significant difference in 8-OHdG levels relative to those without HT (median 7.9 ng/mg creatinine vs 8.8 ng/mg creatinine; p > 0.05). Simple linear correlation and stepwise multiple linear regression analyses revealed that 8-OHdG levels correlated independently, significantly and positively with PWV among T2DM patients with HT (r = 0.33, p < 0.05; β= 0.23, p < 0.05). No significant correlation was observed between 8-OHdG levels and PWV among T2DM patients without HT.

CONCLUSION

In the hypertensive state, oxidative stress can be responsible for the development of arterial stiffness, even in patients with fairly well controlled T2DM. Oxidative stress management may be necessary for the prevention of cardiovascular disease in this population.

The Relationship between Estimated Glomerular Filtration Rate and Diabetic Retinopathy

Diabetic retinopathy (DR) is the leading cause of visual impairment and blindness in working-aged people. Several studies have suggested that glomerular filtration rate (GFR) was correlated with DR. This is a hospital-based study and the aim of it was to examine the relationship between the GFR and DR in patients with type 2 diabetes mellitus (T2DM). We used CKD-EPI equation to estimate GFR and SPSS 19.0 and EmpowerStats software to assess their relationship. Among the 1613 participants (aged 54.75 ± 12.19 years), 550 (34.1%) patients suffered from DR. The multivariate analysis revealed that the risk factors for DR include age (P < 0.001, OR = 0.940), duration of diabetes (P < 0.001, OR = 1.163), hemoglobin A1c (P = 0.007, OR = 1.224), systolic blood pressure (P < 0.001, OR = 1.032), diastolic blood pressure (P = 0.007, OR = 0.953), high density lipoprotein cholesterol (P = 0.024, OR = 3.884), and eGFR (P = 0.010, OR = 0.973). Through stratified analysis and saturation effect analysis, our data suggests that eGFR of 99.4 mL/min or lower might imply the early stage of DR in diabetic patients. Thus, the evaluation of eGFR has clinical significance for the early diagnosis of DR.

Arterial stiffness in diabetes mellitus

Arterial stiffness is an age-related process that is a shared consequence of numerous diseases including diabetes mellitus (DM), and is an independent predictor of mortality both in this population and in the general population. While much has been published about arterial stiffness in patients with DM, a thorough review of the current literature is lacking. Using a systematic literature search strategy, we aimed to summarize our current understanding related to arterial stiffness in DM. We review key studies demonstrating that, among patients with established DM, arterial stiffness is closely related to the progression of complications of DM, including nephropathy, retinopathy, and neuropathy. It is also becoming clear that arterial stiffness can be increased even in pre-diabetic populations with impaired glucose tolerance, and in those with the metabolic syndrome (METS), well before the onset of overt DM. Some data suggests that arterial stiffness can predict the onset of DM. However, future work is needed to further clarify whether large artery stiffness and the pulsatile hemodynamic changes that accompany it are involved in the pathogenesis of DM, and whether interventions targeting arterial stiffness are associated with improved clinical outcomes in DM. We also review of the potential mechanisms of arterial stiffness in DM, with particular emphasis on the role of advanced glycation endproducts (AGEs) and nitric oxide dysregulation, and address potential future directions for research.

Fluid overload, pulse wave velocity, and ratio of brachial pre-ejection period to ejection time in diabetic and non-diabetic chronic kidney disease

Fluid overload is one of the characteristics in chronic kidney disease (CKD). Changes in extracellular fluid volume are associated with progression of diabetic nephropathy. Not only diabetes but also fluid overload is associated with cardiovascular risk factors The aim of the study was to assess the interaction between fluid overload, diabetes, and cardiovascular risk factors, including arterial stiffness and left ventricular function in 480 patients with stages 4–5 CKD. Fluid status was determined by bioimpedance spectroscopy method, Body Composition Monitor. Brachial-ankle pulse wave velocity (baPWV), as a good parameter of arterial stiffness, and brachial pre-ejection period (bPEP)/brachial ejection time (bET), correlated with impaired left ventricular function were measured by ankle-brachial index (ABI)-form device. Of all patients, 207 (43.9%) were diabetic and 240 (50%) had fluid overload. For non-diabetic CKD, fluid overload was associated with being female (β = –2.87, P = 0.003), heart disease (β = 2.69, P = 0.04), high baPWV (β = 0.27, P = 0.04), low hemoglobin (β = –1.10, P<0.001), and low serum albumin (β = –5.21, P<0.001) in multivariate analysis. For diabetic CKD, fluid overload was associated with diuretics use (β = 3.69, P = 0.003), high mean arterial pressure (β = 0.14, P = 0.01), low bPEP/ET (β = –0.19, P = 0.03), low hemoglobin (β = –1.55, P = 0.001), and low serum albumin (β = –9.46, P<0.001). In conclusion, baPWV is associated with fluid overload in non-diabetic CKD and bPEP/bET is associated with fluid overload in diabetic CKD. Early and accurate assessment of these associated cardiovascular risk factors may improve the effects of entire care in late CKD.

Quantitative imaging biomarkers for the evaluation of cardiovascular complications in type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a prevalent condition in aged populations. Cardiovascular diseases are leading causes of death and disability in patients with T2DM. Traditional strategies for controlling the cardiovascular complications of diabetes primarily target a cluster of well-defined risk factors, such as hyperglycemia, lipid disorders and hypertension. However, there is controversy over some recent clinical trials aimed at evaluating efficacy of intensive treatments for T2DM. As a powerful tool for quantitative cardiovascular risk estimation, multi-disciplinary cardiovascular imaging have been applied to detect and quantify morphological and functional abnormalities in the cardiovascular system. Quantitative imaging biomarkers acquired with advanced imaging procedures are expected to provide new insights to stratify absolute cardiovascular risks and reduce the overall costs of health care for people with T2DM by facilitating the selection of optimal therapies. This review discusses principles of state-of-the-art cardiovascular imaging techniques and compares applications of those techniques in various clinical circumstances. Individuals measurements of cardiovascular disease burdens from multiple aspects, which are closely related to existing biomarkers and clinical outcomes, are recommended as promising candidates for quantitative imaging biomarkers to assess the responses of the cardiovascular system during diabetic regimens.

Association of bilateral brachial-ankle pulse wave velocity difference with peripheral vascular disease and left ventricular mass index

Unequal arterial stiffness had been associated with cardiovascular risks. We investigated whether an association existed between unequal arterial stiffness indicated by bilateral brachial-ankle pulse wave velocity (baPWV) difference and ankle-brachial index (ABI), baPWV, echocardiographic parameters and interarm and interankle systolic blood pressure (BP) differences. A total of 1111 patients referred for echocardiographic examination were included in this study. The BPs, ABI and baPWV were measured simultaneously by an ABI-form device. The ΔbaPWV was defined as absolute value of difference between bilateral baPWV. We performed three multivariate analyses for determining the factors associated with a ΔbaPWV ≧ 185 cm/s (90 percentile of ΔbaPWV) (model 1: significant variables in univariate analysis and ABI <0.9 and baPWV; model 2: significant variables in univariate analysis and left ventricular mass index [LVMI]; model 3: significant variables in univariate analysis and interankle systolic BP difference ≧ 15 mmHg). The ABI <0.9 and high baPWV (both P<0.001) in model 1, high LVMI (P = 0.021) in model 2 and an interankle systolic BP difference ≧ 15 mmHg (P = 0.026) in model 3 were associated with a ΔbaPWV ≧ 185 cm/s, but the interarm systolic BP difference ≧ 10 mmHg was not (P = NS). Our study demonstrated ABI <0.9, high baPWV, high LVMI and an interankle systolic BP difference ≧ 15 mmHg were associated with unequal arterial stiffness.