Pulse wave velocity and cardiac autonomic function in type 2 diabetes mellitus

Artificial light at night affects the daily profile of pulse pressure and protein expression in the thoracic aorta of rats

Artificial light at night (ALAN) disrupts 24-h variability of blood pressure, but the molecular mechanisms underlying these effects are unknown. Therefore, we analysed the daily variability of pulse pressure, the maximum value of acceleration rate of aortic pressure (dP/dt(max)) measured by telemetry and protein expression in the thoracic aorta of normotensive male rats exposed to ALAN (1-2 lx) for 3 weeks. Daily, 24-h variability of pulse pressure and dP/dt(max) was observed during a regular light/dark regimen with higher values during the dark compared to the light phase of the day. ALAN suppressed 24-h variability and enhanced ultradian (<12-h) periods of pulse pressure and dP/dt(max) in duration-dependent manners. From beat-to-beat blood pressure variability, ALAN decreased low-frequency bands (a sympathetic marker) and had minimal effects on high-frequency bands. At the molecular level, ALAN decreased angiotensin II receptor type 1 expression and reduced 24-h variability. ALAN caused the appearance of 12-h oscillations in transforming growth factor β1 and fibulin 4. Expression of sarco/endoplasmic reticulum Ca2+-ATPase type 2 was increased in the middle of the light and dark phase of the day, and ALAN did not affect its daily and 12-h variability. In conclusion, ALAN suppressed 24-h variability of pulse pressure and dP/dt(max), decreased the power of low-frequency bands and differentially affected the expression of specific proteins in the rat thoracic aorta. Suppressed 24-h oscillations by ALAN underline the pulsatility of individual endocrine axes with different periods, disrupting the cardiovascular control of central blood pressure.

Impact of supra-maximal interval training vs. high-intensity interval training on cardiac auto-regulation response in physically active adults

PURPOSE

This study aimed to examine the impact of supra-maximal interval training (SMIT) and high-intensity interval training (HIIT) on cardiac auto-regulation response.

METHODS

Physically active young adults volunteered to participate in the study with a randomized cross-over counterbalanced design (N = 12). HIIT sessions consisted of 20 bouts of 10 s of exercise followed by 50 s of recovery, totaling 20 min at two different intensities; "all-out (SMIT)" vs. "115-130% Wmax (HIIT)". The cardiac auto-regulation included heart rate variability (HRV) and vascular function. HRV and vascular function were measured at baseline and five different time points after acute exercise.

RESULTS

The SMIT was higher in workload (31%), peak heart rate (28%), and rate of perceived exertion (40%) compared with HIIT (all p < 0.001). The R-R interval, NN50, and pNN50 measured until 60 min after acute exercise was higher in the HIIT compared with SMIT (all p < 0.05). The SMIT elicited a greater shift in ln LF/HF ratio immediately after acute exercise (3802%, p < 0.01) and induced a decrease in bilateral ba-PWV at the time point 5 min after acute exercise, persisting until 65 min after (p < 0.05). Yet, HIIT showed no change over time in the frequency domain of HRV and blood vascular tone after cessation of acute exercise.

CONCLUSION

Our findings confirmed that SMIT is a more potent modulator of the autonomic nervous system compared with HIIT. Further study is needed to monitor through complete recovery to baseline, to understand acute cardiac auto-regulation response after cessation of various exercise intensities identical interval training protocol.

Baroreflex Sensitivity as a Surrogate Biomarker for Concurrently Assessing the Severity of Arterial Stiffness and Cardiovascular Autonomic Neuropathy in Individuals with Type 2 Diabetes

This study aimed to investigate whether baroreflex sensitivity (BRS) could serve as a reliable metric for assessing cardiovascular autonomic neuropathy (CAN) and concurrently act as a surrogate biomarker for evaluating the severity of arterial stiffness and CAN in individuals diagnosed with type 2 diabetes mellitus (T2DM). Participants underwent brachial-ankle pulse wave velocity (baPWV) as well as autonomic function evaluations encompassing the Sudoscan-based modified composite autonomic scoring scale (CASS), baroreflex sensitivity, and heart rate variability in time domains and frequency domains. Linear regression analysis was performed to evaluate the influence of independent variables on baPWV and modified CASS. Participants with higher baPWV values were older, with longer diabetes duration, lower body weight, body mass index, waist circumference, elevated systolic and diastolic blood pressure, and mean arterial blood pressure. They also exhibited a higher prevalence of retinopathy as the underlying disease and reduced estimated glomerular filtration rate. Multiple linear regression analysis revealed that age and BRS were significantly associated with baPWV while diabetes duration, UACR, and BRS were significantly associated with modified CASS. Our study confirms the significant association of BRS with baPWV and modified CASS in T2DM, highlighting its pivotal role in linking microvascular and macrovascular complications. This supports BRS as a surrogate marker for assessing both the severity of arterial stiffness and cardiovascular autonomic neuropathy in T2DM, enabling the early identification of complications.

Autonomic dysfunction is associated with the development of arterial stiffness: the Whitehall II cohort

This study aims to examine the association between baseline level and change of autonomic nervous function with subsequent development of arterial stiffness. Autonomic nervous function was assessed in 4901 participants of the Whitehall II occupational cohort by heart rate variability (HRV) indices and resting heart rate (rHR) three times between 1997 and 2009, while arterial stiffness was assessed by carotid-femoral pulse wave velocity (PWV) measured twice between 2007 and 2013. First, individual HRV/rHR levels and annual changes were estimated. Then, we modelled the development of PWV by HRV/rHR using linear mixed effect models. First, we adjusted for sex and ethnicity (model 1), and then for socioeconomic and lifestyle factors, various clinical measurements, and medications (model 2). A decrease in HRV and unchanged rHR was associated with subsequent higher levels of PWV, but the effect of a change in HRV was less pronounced at higher ages. A typical individual aged 65 years with a SDNN level of 30 ms and a 2% annual decrease in SDNN had 1.32 (0.95; 1.69) higher PWV compared to one with the same age and SDNN level but with a 1% annual decrease in SDNN. Further adjustment had no major effect on the results. People who experience a steeper decline in autonomic nervous function have higher levels of arterial stiffness. The association was stronger in younger people.

Association of arterial stiffness and neuropathy in diabetes: a systematic review and meta-analysis

Evidence is still emerging on the relationships of arterial stiffness with cardiac autonomic neuropathy (CAN) and peripheral neuropathy (PN). To our knowledge no systematic reviews or meta-analyses of these associations have been published. The purpose of our review was to assess the association of arterial stiffness with each type of neuropathy. Medline and Embase were systematically searched for observational studies of arterial stiffness and neuropathy.The systematic review of 60 studies (25 for CAN and 37 for PN), 59 including people with diabetes, showed arterial stiffness overall was higher in people with neuropathy than people without neuropathy. Forty-three studies were included in the meta-analysis. For CAN (19 studies), arterial stiffness was increased in people with neuropathy compared with without, as measured by pulse wave velocity (PWV) (mean difference: 1.32 m/s, 95% CI 0.82 to 1.81, p<0.00001), pulse pressure (PP) (mean difference: 6.25 mmHg, 95% CI 4.51 to 7.99, p<0.00001) or augmentation index (mean difference: 5.52%, 95% CI 3.46 to 7.58, p<0.0001). For PN (26 studies), arterial stiffness was increased in people with neuropathy compared with those without, as measured by PWV (mean difference: 1.22 m/s, 95% CI 0.87 to 1.58, p<0.00001) or PP (mean difference: 4.59 mmHg, 95% CI 2.96 to 6.22, p<0.00001). Only two cohort studies were located so the temporality of the association between arterial stiffness and neuropathy remains unclear. Increased arterial stiffness is associated with CAN and PN.PROSPERO registration number: CRD42019129563.

Relationship between reduced heart rate variability and increased arterial stiffness evaluated by the cardio-ankle vascular index in people with type 2 diabetes

Objective

Cardiac autonomic neuropathy (CAN) is an independent risk factor for cardiovascular mortality and also is associated with a high risk of lethal arrhythmias and sudden death in people with type 1 or 2 diabetes. Heart rate variability (HRV) is an index of cardiac autonomic function. To investigate the relationship between HRV and arterial stiffness evaluated by the cardio-ankle vascular index (CAVI), a relatively new marker for arterial stiffness and a predictor of cardiovascular disease, in patients with type 2 diabetes.

Materials and methods

We studied consecutive 313 patients with type 2 diabetes in a cross-sectional design. HRV was estimated by the coefficient of variation of 100 R-R intervals (CVR-R) at rest and during deep breathing (DB). The difference in CVR-R was defined as CVR-R during DB minus CVR-R at rest. Arterial stiffness was evaluated by CAVI, which is independent of blood pressure (BP). A CAVI greater than or equal to 9.0 was defined as significant arterial stiffening.

Results

Linear regression analysis showed that CAVI correlated positively with age, duration of diabetes, urinary albumin creatinine ratio (UACR), CVR-R during DB, and the difference in CVR-R and negatively with body mass index (BMI), estimated glomerular filtration rate, and sensory nerve conduction velocity and action potential of the sural nerve. Multivariate analysis found that age, BMI, systolic blood pressure, UACR, and CVR-R during DB were independently associated with arterial stiffness determined by CAVI. The CVR-R at rest and during deep breathing was significantly lower in the patients with arterial stiffness than in those without it.

Conclusion

Low HRV estimated by CVR-R during DB is closely associated with arterial stiffness measured by CAVI in people with type 2 diabetes, suggesting that arterial stiffness associated with CAN may be an independent risk factor for cardiovascular disease in people with type 2 diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-022-00604-y.

Pathophysiological and clinical aspects of the circadian rhythm of arterial stiffness in diabetes mellitus: A minireview

Several cross-sectional trials have revealed increased arterial stiffness connected with the cardiac autonomic neuropathy in types 2 and 1 diabetic patients. The pathophysiological relationship between arterial stiffness and autonomic dysfunction in diabetes mellitus is still underinvestigated and the question whether the presence of cardiac autonomic neuropathy leads to arterial stiffening or increased arterial stiffness induced autonomic nervous system impairment is still open. Both arterial stiffness and dysfunction of the autonomic nervous system have common pathogenetic pathways, counting state of the chronic hyperinsulinemia and hyperglycemia, increased formation of advanced glycation end products, activation of protein kinase C, development of endothelial dysfunction, and chronic low-grade inflammation. Baroreceptor dysfunction is thought to be one of the possible reasons for the arterial wall stiffening development and progression. On the contrary, violated autonomic nervous system function can affect the vascular tone and by this way alter the large arteries walls elastic properties. Another possible mechanism of attachment and/or development of arterial stiffness is the increased heart rate and autonomic dysfunction corresponding progression. This minireview analyzes the current state of the relationship between the diabetes mellitus and the arterial stiffness. Particular attention is paid to the analysis, interpretation, and application of the results obtained in patients with type 2 diabetes mellitus and diabetic cardiac autonomic neuropathy.

Diabetes Affects the Relationship between Heart Rate Variability and Arterial Stiffness in a Gender-Specific Manner

Background and Aims: Heart rate variability (HRV), i.e., the beat-by-beat fluctuations in heart rate (HR) reflecting the autonomic nervous system balance, is altered in patients with diabetes. This has been associated with arterial aging (stiffer arteries) and differs in men and women. The present study hypothesized that the impact of HRV on arterial aging, indexed as carotid–femoral pulse wave velocity (PWV), differs in a gender-specific manner and is affected by diabetes mellitus. Method: A total of 422 outpatients (187 women and 235 men) were studied. PWV was measured using the validated SphygmoCor device (AtCor Medical). Time-domain and frequency-domain parameters were measured to assess HRV. Results: The prevalence of diabetes was 30.8% with a slight, but nonsignificant, greater prevalence in men. Both age and SBP were independent determinants of PWV in each of the four groups (men and women with or without diabetes). Low-frequency activity was inversely correlated with PWV. It was greater in women without diabetes, but it was not significant in men regardless of the presence of diabetes. Conclusions: Beyond age, blood pressure, and diabetes, impaired cardiac autonomic function assessed by determination of HRV was significantly associated with arterial aging. The association between lower sympathetic and parasympathetic activity and stiffer arteries was significant in women, but not in men.

Vascular Age, Metabolic Panel, Cardiovascular Risk and Inflammaging in Patients With Rheumatoid Arthritis Compared With Patients With Osteoarthritis

Introduction

The risk of cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA) is 1.5–2 times higher than the general population. The fundamental risk factor for CVD is age, related to alterations at the arterial level. The aim of the study was to compare vascular age (VA) in RA patients under a strict treat-to-target (T2T) strategy with Osteoarthritis (OA) patients without strict follow up and to assess the influence of inflammaging (chronic, sterile, low-grade inflammation related to aging) and metabolic markers on VA.

Materials and Methods

This was an analytical cross-sectional study. Patients with RA (under a strict a T2T strategy) and OA patients without strict clinical follow-up were included. Patients with a history of uncontrolled hypertension, CVD, and/or current smoking were excluded. Sociodemographic, physical activity, and toxic exposure data were obtained. Waist-hip ratio and body mass index (BMI) were measured. DAS-28 (RA) and inflammatory markers, lipid profile, and glycaemia were analyzed. Pulse wave velocity (PWV) was measured (oscillometric method, Arteriograph-TensioMed®). VA was calculated based on PWV. Eleven components of inflammaging [six interleukins, three metalloproteinases (MMP), and two tissue inhibitors of metalloproteinases (TIMP)] were evaluated (Luminex® system). Univariate and bivariate analyzes (Mann Whitney U and chi-square) and correlations (Spearmans Rho) were done to compare the two groups.

Results

A total of 106 patients (74% women) were included, 52/RA and 54/OA. The mean age was 57 (Interquartile range - IQR 9 years). The BMI, waist circumference, and weight were higher in patients with OA (p &lt; 0.001). RA patients had low disease activity (DAS-28-CRP). There were no differences in VA, inflammaging nor in PWV between the two groups. VA had a positive, but weak correlation, with age and LDL. In group of RA, VA was higher in those who did not receive methotrexate (p = 0.013). LDL levels correlated with MMP1, TIMP1, and TIMP2.

Conclusions

When comparing RA patients with low levels of disease activity with OA patients with poor metabolic control, there are no differences in VA. Furthermore, methotrexate also influences VA in RA patients. This shows that implemented therapies may have an impact on not only the inflammatory state of the joint but also CVD risk.

Effect of alpha-lipoic acid on arterial stiffness parameters in type 2 diabetes mellitus patients with cardiac autonomic neuropathy

Objective. Significantly underdiagnosed, diabetes-associated cardiac autonomic neuropathy (CAN) causes a wide range of cardiac disorders that may cause life-threatening outcomes. This study investigated the effects of alpha-lipoic acid (ALA) on arterial stiffness and insulin resistance (IR) parameters in type 2 diabetes mellitus (T2D) patients and definite CAN. Methods. A total of 36 patients with T2D and a definite stage of CAN were recruited. This investigation was carried out on two separate arms: traditional hypoglycemic therapy (n=18, control) and ALA (n=18) 600 mg in film-coated tablets/q.d. in addition to traditional hypoglycemic therapy. The duration of the study was three months. Results. In subjects with T2D and definite stage of СAN, treatment with ALA resulted in a significant decrease of glucose, immunoreactive insulin concentration, and Homeostasis Model Assessment (HOMA)-IR (HOMA-IR) parameters; pulse wave velocity (PWV), aorta augmentation index (AIxao) during the active period of the day and decrease of PWV, AIxao, and brachial augmentation index during the passive period of the day compared with the results, obtained in the control group. Therefore, the administration of ALA to patients with T2D for three months promotes the improvement of glucose metabolism and arterial stiffness parameters. Conclusions. In patients with T2D and definite stage of СAN treatment with ALA improved HOMA-IR and arterial stiffness parameters. These findings can be of clinical significance for the complex treatment of diabetes-associated CAN.

Retracted: Effect of dipeptidyl peptidase-4 inhibitors on the progression of atherosclerosis in patients with type 2 diabetes mellitus: A meta-analysis of randomised controlled trials

Yang, T, Li, W, Kan, Z, Liu, Y, Peng, M, Shi, H, Effect of dipeptidyl peptidase-4 inhibitors on the progression of atherosclerosis in patients with type 2 diabetes mellitus: A meta-analysis of randomised controlled trials. Int J Clin Pract. 2021; 00:e14213. https://onlinelibrary.wiley.com/doi/10.1111/ijcp.14213. The above article from the International Journal of Clinical Practice, published online on 5 April 2021 in Wiley Online Library (wileyonlinelibrary.com), has been retracted at the request of the authors, and by agreement of the journal Editor in Chief, Charles Young, and John Wiley and Sons Ltd. The retraction has been agreed following an author review of the research which led to the removal of some studies which did not meet the inclusion criteria. Following the removal of these studies the overall sample size was too small and the studies still included too heterogenuous for the results and conclusions to be reliable.

Cardiovascular disease in patients with type 1 diabetes: Early evaluation, risk factors and possible relation with cardiac autoimmunity

Cardiovascular disease now is the leading cause of mortality among patients with type 1 diabetes (T1D). The risk of death from cardiovascular events in subjects with T1D is 2-10 times higher than the general population, depending on blood glucose control. Although complications of cardiovascular disease occur in middle and old age, pathological processes begin in childhood. Some methods used to evaluate subclinical cardiovascular disease, such as carotid intima-media thickness and pulse wave velocity, can detect early cardiovascular abnormalities in adolescence. The effect of risk factors including hypertension, dyslipidemia and diabetic nephropathy on cardiovascular disease has been well studied. According to the current clinical practice recommendations from the American Diabetes Association, cardiovascular risk factors should be systematically assessed at least annually and treated as recommended. And yet, the effects of intensive insulin therapy on cardiovascular risk, as well as the mechanisms of cardiac autoimmunity require further studying. This review concentrates on the cardiovascular risk in type 1 diabetes in order to provide a comprehensive outlook of its epidemiology, early assessment, risk factors and possible relations with cardiac autoimmunity, aiming to propose promising therapeutic strategies.

Clinical significance of heart rate variability for the monitoring of cardiac autonomic neuropathy in end-stage renal disease patients

BACKGROUND AND AIMS

The aim of this study is to determine whether the measurement of continuous heart rate variability (HRV) is useful in the evaluation of cardiac autonomic neuropathy (CAN) in end-stage renal disease (ESRD) patients.

METHODS AND RESULTS

This cross-sectional study was performed at Seoul St. Mary's hospital between June 2017 and February 2018. Seventy-seven ESRD patients, and 29 healthy controls (HCs) were asked to wear a continuous ambulatory HRV monitor for 24 h. General cardiac function was evaluated using transthoracic echocardiogram (TTE), pulse wave velocity (PWV), coronary calcium scoring (CCS), and 24-h ambulatory blood pressure monitoring (ABPM). HRV parameters of ESRD patients and HCs, and the correlation of HRV parameters with cardiovascular screening methods were observed. All HRV parameters were significantly decreased in ESRD patients compared to HCs (P < 0.001). In the correlation analysis between TTE results and HRV parameters, 24-h standard deviation of all N-N intervals (24SDNN), 24-h standard deviation of sequential 5-min N-N interval means (24DANN) and Low Frequency Power/High Frequency Power (LF/HF) ratio showed negative correlations with E/e', LAVI and TR velocity which are representative indices for the diastolic function of the heart (P < 0.05). HRV parameters showed negative correlations with baPWV, CCS, and 24-h ABPM results as well (P < 0.05). Hemoglobin and serum albumin showed positive correlations with HRV parameters, and glucose, BUN, creatinine, and iPTH levels showed negative correlations (P < 0.05).

CONCLUSION

Continuous HRV monitoring may be a useful tool for the evaluation of CAN in ESRD.

Variability of peripheral pulse wave velocity in patients with diabetes mellitus type 2 during orthostatic challenge

Diabetes mellitus 2 (DM2) is the seventh cause of death worldwide. One of the reasons is late diagnosis of vascular damage. Pulse wave velocity (PWV) has become an independent marker of arterial stiffness and cardiovascular risk. Moreover, the previous studies have shown the importance of beat-to-beat PWV measurement due to its variability among the heart cycle. However, variability of PWV (PWVv) of the whole body hasn't been examined yet. We have studied a group of DM II and heathy volunteers, to investigate the beat-to-beat mean PWV (PWVm) and PWVv in the different body positions. PWV of left lower and upper extremities were measured in DM2 (7 m/8 f, age 68+/-10 years, BP 158/90+/-19/9 mm Hg) and healthy controls (5 m/6 f, age 23+/-2 years, BP 117/76+/-9/5 mm Hg). Volunteers were lying in the resting position and of head-up-tilt in 45° (HUT) for 6 min. PWVv was evaluated as a mean power spectrum in the frequency bands LF and HF (0.04-0.15 Hz, 0.15-0.5 Hz). Resting PWVm of upper extremity was higher in DM2. HUT increased lower extremity PWVm only in DM2. Extremities PWVm ratio was significantly lower in DM2 during HUT compared to controls. LF and HF PWVv had the same response to HUT. Resting PWVv was higher in DM2. Lower extremity PWVv increased during HUT in both groups. PWVm and PWVv in DM2 differed between extremities and were significantly influenced by postural changes due to hydrostatic pressure. Increased resting PWVm and PWVv in DM2 is a marker of increased arterial stiffness.

Cardiovascular risk and heart rate variability in young adults with type 2 diabetes and arterial stiffness: The SEARCH for Diabetes in Youth Study

AIMS

To evaluate cardiovascular risk factors and heart rate variability (HRV) in young adults with type 2 diabetes and arterial stiffness and to explore the relationship between HRV and arterial stiffness.

METHODS

We studied 185 young adults with youth-onset T2D enrolled in the SEARCH for Diabetes in Youth Study. Cardiovascular risk factors and HRV were compared between individuals with and without type 2 diabetes and arterial stiffness (defined as a pulse wave velocity greater than the 90th percentile of healthy controls, >6.767 m/s). Semiparametric regression evaluated the independent relationship between HRV and PWV.

RESULTS

Participants with T2D and arterial stiffness were more likely to be older, non-Hispanic Black, have higher systolic and diastolic blood pressure, greater adiposity and obesity-related dyslipidemia (higher triglycerides and lower HDLC). Participants with T2D and arterial stiffness also had lower overall HRV (lower SDNN) with parasympathetic loss (lower RMSSD and PNN50), p < 0.05. Lower HRV tended to be but was not significantly associated with arterial stiffness after adjustment for age, race/ethnicity, sex and cardiovascular risk factors (beta coefficient = -1.11, p = 0.08).

CONCLUSIONS

Youth with T2D and arterial stiffness have a worse cardiovascular risk profile, specifically risk factors related to the metabolic syndrome and lower HRV.

Potential therapeutic effects of endothelial cells trans-differentiated from Wharton's Jelly-derived mesenchymal stem cells on altered vascular functions in aged diabetic rat model

BACKGROUND

Diabetes mellitus in elderly represents an exceptional subset in the population vulnerable to cardiovascular events. As aging, diabetes mellitus and hypertension share common pathways, an ideal treatment should possess the ability to counter more than one of, if not all, the underlying mechanisms. Stem cells emerged as a potential approach for complicated medical problems. We tested here the possible role of trans-differentiated endothelial cells (ECs) in the treatment of diabetes mellitus in old rats.

METHODS

Mesenchymal stem cells where isolated from umbilical cord Wharton's Jelly and induced to differentiate into endothelial like-cells using vascular endothelial growth factor-enriched media. Thirty aged male Wistar albino rats were used in the present study. Rats were divided (10/group) into: control group (18-20 months old, weighing 350-400 g, received single intraperitoneal injection as well as single intravenous injection via tail vein of the vehicles), aged diabetic group (18-20 months old, weighing 350-400 g, received single intraperitoneal injection of 50 mg/kg streptozotocin, and also received single intravenous injection of saline via tail vein), and aged diabetic + ECs group (18-20 months old, weighing 350-400 g, received single intraperitoneal injection of 50 mg/kg streptozotocin, and also received single intravenous injection of 2*10⁶ MSC-derived ECs in 0.5 ml saline via tail vein) groups. Assessment of SBP, aortic PWV, and renal artery resistance was performed. Serum levels of ET1, ANG II, IL-6, TNF-α, MDA, ROS, and VEGF were evaluated, as well as the aortic NO tissue level and eNOS gene expression. Histopathological and immunostaining assessments of small and large vessels were also performed.

RESULTS

Induction of diabetes in old rats resulted in significant increase in SBP, aortic PWV, renal artery resistance, and serum levels of ET1, ANG II, IL-6, TNF-α, MDA, ROS, and VEGF. While there was significant decrease in aortic NO tissue level and eNOS gene expression in the aged diabetic group when compared to aged control group. ECs treatment resulted in significant improvement of endothelial dysfunction, inflammation and oxidative stress.

CONCLUSION

We report here the potential therapeutic role of trans-differentiated ECs in aged diabetics. ECs demonstrated anti-inflammatory, antioxidant, gene modifying properties, significantly countered endothelial dysfunction, and improved vascular insult.

Heart Rate Variability and Cardiac Autonomic Dysfunction: Prevalence, Risk Factors, and Relationship to Arterial Stiffness in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) Study

OBJECTIVE

To determine whether prior type 2 diabetes (T2D) treatment or glycemic control over time are independently associated with heart rate variability (HRV) and whether the presence of cardiac autonomic dysfunction is associated with arterial stiffness in young adults with youth-onset T2D enrolled in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study.

RESEARCH DESIGN AND METHODS

Heartbeats over 10 min were measured to derive the normal R-Rs (NN intervals). Outcomes included the standard deviation of the NN intervals (SDNN), the root mean square differences of successive NN intervals (RMSSD), percent of NN beats that differ by more than 50 ms (PNN50), and the low-frequency (LF) power domain, high-frequency (HF) power domain, and their ratio (LF:HF). Autonomic dysfunction was defined as ≥3 of 5 abnormal HRV indices compared with obese controls from a separate study.

RESULTS

A total of 397 TODAY participants were evaluated 7 years after randomization. TODAY participants had reduced HRV (SDNN 58.1 ± 29.6 ms vs. controls 67.1 ± 25.4 ms; P < 0.0001) with parasympathetic loss (RMSSD 53.2 ± 36.7 ms vs. controls 67.9 ± 35.2 ms; P < 0.0001) with sympathetic overdrive (LF:HF ratio 1.4 ± 1.7 vs. controls 1.0 ± 1.1; P < 0.0001). Cardiac autonomic dysfunction was present in 8% of TODAY participants, and these participants had greater pulse wave velocity compared with those without dysfunction (P = 0.0001). HRV did not differ by randomized treatment, but higher hemoglobin A1c (HbA_1c) over time was independently associated with lower SDNN and RMSSD and higher LF:HF ratio after adjustment for age, race-ethnicity, sex, and BMI.

CONCLUSIONS

Young adults with youth-onset T2D show evidence of cardiac autonomic dysfunction with both parasympathetic and sympathetic impairments that are associated with higher HbA_1c.

Effect of 12-month intervention with low-dose atorvastatin on pulse wave velocity in subjects with type 2 diabetes and dyslipidaemia

Cardiovascular disease is the leading cause of morbidity and mortality in subjects with type 2 diabetes mellitus. Increased aortic stiffness, assessed with the carotid-femoral pulse wave velocity, is an independent risk factor for cardiovascular disease. Statins reduce effectively cardiovascular disease and mortality in high-risk patients. The aim of this prospective non-randomized, observational study was to examine the impact of treatment with either 10 mg atorvastatin plus diet or diet alone on carotid-femoral pulse wave velocity in subjects with type 2 diabetes mellitus and dyslipidaemia. A total of 79 subjects with type 2 diabetes mellitus and dyslipidaemia were included; 46 subjects were treated with atorvastatin 10 mg daily plus diet and 33 were managed by diet alone for 12 months. Carotid-femoral pulse wave velocity and carotid-radial pulse wave velocity were measured using applanation tonometry. In the atorvastatin-treated group, carotid-femoral pulse wave velocity reduced significantly during the study and there was a trend for reduction in the carotid-radial pulse wave velocity. Total cholesterol, low-density lipoprotein cholesterol, triglycerides and C-reactive protein were reduced only in the atorvastatin-treated participants. No significant changes were found in body mass index, blood pressure, heart rate, diabetes control and high-density lipoprotein cholesterol in either study group. Treatment with low-dose atorvastatin for 12 months improves carotid-femoral pulse wave velocity in subjects with type 2 diabetes mellitus and dyslipidaemia.

The association between pulse wave velocity and peripheral neuropathy in patients with type 2 diabetes mellitus

AIMS

Diabetic peripheral neuropathy (DPN) is the most common diabetic complication, affecting up to half of the patients with type 2 diabetes mellitus (T2DM). Increased aortic stiffness, measured with the carotid-femoral pulse wave velocity (PWV), has been associated with incidence of cardiovascular disease independently of traditional risk factors. Previous data showed associations between risk factors for macroangiopathy and DPN in diabetes. However, the association between PWV and DPN is not well known. In this study we examined the association between PWV and presence as well as severity of DPN in subjects with T2DM.

MATERIAL AND METHODS

A total of 381 patients with T2DM were recruited. Participants were classified as having DPN and not having DPN. PWV was measured at the carotid-femoral segment with a non-invasive method using applanation tonometry. DPN was assessed by determination of the Neuropathy Symptom Score (NSS) and the Neuropathy Disability Score (NDS).

RESULTS

A hundred and seven participants (28.1%) had DPN. Patients with DPN were significantly more often male and older, had longer diabetes duration, higher height, larger waist circumference, higher systolic arterial blood pressure (SBP) and higher PWV (all P<0.05). Furthermore, participants with DPN were treated more often with statins and had lower low density lipoprotein cholesterol; in addition, they were treated more often with antiplatelets, b-blockers and insulin than those without DPN. Univariative logistic regression analysis demonstrated that presence of DPN was significantly associated with age, male gender, longer diabetes duration, height, waist circumference, SBP, PWV, dyslipidemia, HbA1c, retinopathy, nephropathy and peripheral arterial disease. Multivariate logistic regression analysis, after adjustment for age, gender, waist circumference, SBP, nephropathy and use of b-blockers, demonstrated that the odds [OR (95% confidence intervals)] of peripheral neuropathy were associated significantly and independently only with diabetes duration [1.044 (1.009-1.081), P=0.013], height [1.075 (1.041-1.110), P<0.001], HbA1c [1.468 (1.164-1.851), P<0.001], PWV [1.174 (1.054-1.309), P=0.004], dyslipidemia [1.941 (1.015-3.713), P=0.045], retinopathy [4.426 (2.217-8.837), P<0.001] and peripheral arterial disease [4.658 (2.264-9.584), P<0.001]. In addition, multivariate linear regression analysis, after controlling for age, gender, diabetes duration, SBP, HbA1c and nephropathy, demonstrated that an increased NDS was significantly and independently associated with height [standardized regression coefficient (beta=0.229, P<0.001)], PWV (beta=0.197, P<0.001), retinopathy (beta=0.268, P<0.001) and peripheral arterial disease (beta=0.374, P<0.001).

CONCLUSION

Increased PWV is associated strongly and independently not only with the presence but also with the severity of DPN in patients with T2DM, irrespective of known risk factors.

Comparison of the ability to identify arterial stiffness between two new anthropometric indices and classical obesity indices in Chinese adults

BACKGROUND AND AIMS

The association between anthropometric indices of body composition and arterial stiffness is inconclusive. The objective of this study was to examine the predictive ability of two new obesity indices: a body shape index (ABSI), and a body roundness index (BRI), for the identification of arterial stiffness among Chinese adults, as well as to compare the relative strength of association between the anthropometric indices and arterial stiffness.

METHODS

A total of 10,197 subjects were recruited in this cross-sectional study. We tested the association between anthropometric indices (body mass index [BMI], waist circumference [WC], waist-height-ratio [WHtR], ABSI and BRI) and brachial-ankle pulse wave velocity (PWV). Receiver operating characteristic curve and area under curve (AUC) were employed to evaluate the predictive value of the anthropometric indices for identification of arterial stiffness.

RESULTS

After adjusting for confounding variables, BRI (linear regression: 0.112; AUC: 0.726; OR: 1.228 for female and linear regression: 0.047; AUC: 0.631; OR: 1.173 for male) exhibited a more powerful predictive ability of arterial stiffness than ABSI (linear regression: 0.110; AUC: 0.674; OR: 1.315 for female and linear regression: 0.058; AUC: 0.610; OR: 1.150 for male) and WC (linear regression: 0.078; AUC: 0.699; logistic regression: negative for female and linear regression: negative; AUC: 0.593; logistic regression: negative for male) while having a similar predictive value to that of WHtR (linear regression: 0.113; AUC: 0.726; OR: 1.228 for female and linear regression: 0.047; AUC: 0.631; OR: 1.185 for male) among both sexes. BMI (linear and logistic regression: negative; AUC: 0.660 for female and 0.568 for male) had the lowest predictive power in both sex categories. The optimal cut-off of WHtR for detecting arterial stiffness was 0.49 in females and 0.53 in males, that of BRI was 3.19 in females and 3.89 in males.

CONCLUSIONS

WHtR, ABSI and BRI were significantly associated with arterial stiffness. BRI and WHtR, rather than ABSI, showed superior predictive abilities for arterial stiffness in both sexes.