Effect of weight loss and nutritional intervention on arterial stiffness in type 2 diabetes

Vascular ageing: moving from bench towards bedside

Prevention of cardiovascular disease (CVD) remains one of the largest public health challenges of our time. Identifying individuals at increased cardiovascular risk at an asymptomatic, sub-clinical stage is of paramount importance for minimizing disease progression as well as the substantial health and economic burden associated with overt CVD. Vascular ageing (VA) involves the deterioration in vascular structure and function over time and ultimately leads to damage in the heart, brain, kidney, and other organs. Vascular ageing encompasses the cumulative effect of all cardiovascular risk factors on the arterial wall over the life course and thus may help identify those at elevated cardiovascular risk, early in disease development. Although the concept of VA is gaining interest clinically, it is seldom measured in routine clinical practice due to lack of consensus on how to characterize VA as physiological vs. pathological and various practical issues. In this state-of-the-art review and as a network of scientists, clinicians, engineers, and industry partners with expertise in VA, we address six questions related to VA in an attempt to increase knowledge among the broader medical community and move the routine measurement of VA a little closer from bench towards bedside.

Global distributions of age- and sex-related arterial stiffness: systematic review and meta-analysis of 167 studies with 509,743 participants

BACKGROUND

Arterial stiffening is central to the vascular ageing process and a powerful predictor and cause of diverse vascular pathologies and mortality. We investigated age and sex trajectories, regional differences, and global reference values of arterial stiffness as assessed by pulse wave velocity (PWV).

METHODS

Measurements of brachial-ankle or carotid-femoral PWV (baPWV or cfPWV) in generally healthy participants published in three electronic databases between database inception and August 24th, 2020 were included, either as individual participant-level or summary data received from collaborators (n = 248,196) or by extraction from published reports (n = 274,629). Quality was appraised using the Joanna Briggs Instrument. Variation in PWV was estimated using mixed-effects meta-regression and Generalized Additive Models for Location, Scale, and Shape.

FINDINGS

The search yielded 8920 studies, and 167 studies with 509,743 participants from 34 countries were included. PWV depended on age, sex, and country. Global age-standardised means were 12.5 m/s (95% confidence interval: 12.1-12.8 m/s) for baPWV and 7.45 m/s (95% CI: 7.11-7.79 m/s) for cfPWV. Males had higher global levels than females of 0.77 m/s for baPWV (95% CI: 0.75-0.78 m/s) and 0.35 m/s for cfPWV (95% CI: 0.33-0.37 m/s), but sex differences in baPWV diminished with advancing age. Compared to Europe, baPWV was substantially higher in the Asian region (+1.83 m/s, P = 0.0014), whereas cfPWV was higher in the African region (+0.41 m/s, P < 0.0001) and differed more by country (highest in Poland, Russia, Iceland, France, and China; lowest in Spain, Belgium, Canada, Finland, and Argentina). High vs. other country income was associated with lower baPWV (-0.55 m/s, P = 0.048) and cfPWV (-0.41 m/s, P < 0.0001).

INTERPRETATION

China and other Asian countries featured high PWV, which by known associations with central blood pressure and pulse pressure may partly explain higher Asian risk for intracerebral haemorrhage and small vessel stroke. Reference values provided may facilitate use of PWV as a marker of vascular ageing, for prediction of vascular risk and death, and for designing future therapeutic interventions.

FUNDING

This study was supported by the excellence initiative VASCage funded by the Austrian Research Promotion Agency, by the National Science Foundation of China, and the Science and Technology Planning Project of Hunan Province. Detailed funding information is provided as part of the Acknowledgments after the main text.

Impact of Bariatric Surgery on Pulse Wave Velocity as a Measure of Arterial Stiffness: a Systematic Review and Meta-analysis

PURPOSE

Weight loss during post-bariatric surgery period has been linked to both reduced ASCVD mortality and overall mortality. Atherosclerosis causes arteries to lose their elasticity and become more stiff resulting in increased pulse wave velocity (PWV). It has been revealed that PWV favorably predicts subsequent ASCVDs. The goal of this systematic review and meta-analysis was to see how bariatric surgery affected PWV, an index of arterial stiffness.

MATERIALS AND METHODS

A systematic literature search in four databases was performed. Also, Cochrane guidelines were reviewed to determine bias possibility in the related studies. Comprehensive Meta-Analysis (CMA) V2 software is used to conduct the meta-analysis. Studies were evaluated regarding heterogeneity in design, populations under investigation, and treatment duration using random-effects model and the generic inverse variance weighting approach. A random-effect meta-regression approach was used to investigate the association with the estimated effect size. Evaluation of funnel plot, Egger's weighted regression, and Begg's rank correlation tests were utilized to estimate the presence of publication bias in the meta-analysis.

RESULTS

The results of meta-analysis on 13 trials including 1426 individuals demonstrated a remarkable decline of PWV after bariatric surgery (WMD: -0.652, 95% CI: -1.004, -0.301, p<0.001). The random-effects meta-regression revealed no evidence of significant correlation between the changes in PWV and initial BMI, BMI changes, or duration of follow-up.

CONCLUSION

The decrease of PWV might be utilized as an independent surrogate marker of improvement of ASCVD risk after bariatric surgery.

Impact of Intensive Lifestyle Treatment (Diet Plus Exercise) on Endothelial and Vascular Function, Arterial Stiffness and Blood Pressure in Stage 1 Hypertension: Results of the HINTreat Randomized Controlled Trial

Lifestyle modification is an important component of essential hypertension (EH) therapy. The aim of the Hypertension Intensive Nutrition Treatment (HINTreat) parallel, randomized controlled trial was to examine the effect of a 6-month intensive lifestyle treatment (ILT) (diet plus exercise with monthly visits) compared to the usual care. A total of 76 adults with stage 1 EH were randomized (38 in each group). Dietary analysis, anthropometry, physical activity, biochemical and urine profile, blood pressure (BP), asymmetric dimethylarginine (ADMA), central hemodynamics, β-stiffness index and carotid intima media-thickness were evaluated. The dietary inflammatory index (DII) was calculated for each participant from the intake of 29 nutrients/food components. At the end of the trial, participants in the ILT group reduced their 24h urinary Na excretion (p ≤ 0.001), daytime systolic BP (p ≤ 0.048) and mean carotid β-stiffness index (p ≤ 0.005) and ameliorated their lipidemic profile compared to the standard care. Univariate analysis for the total sample showed a strong association between DII and ADMA levels (β = 0.089, p ≤ 0.01). ILT is effective in improving the inflammatory components of the diet and selected cardiometabolic parameters, including arterial stiffness.

The Hardest Part

Aging has a significant impact not only on every single individual but on society as a whole. Today, people throughout the world exhibit an extended lifespan. Therefore, it becomes increasingly important to develop novel concepts that encourage a modern understanding of the aging process. The concept of healthy aging shifts the perception of aging as a burden towards aging as an opportunity for an extended healthy phase in later life. Morbidity and mortality in the elderly population are greatly defined by a raise in the incidence and prevalence of cardiovascular diseases. Consequently, it is critical to identify risk factors and underlying mechanisms that render the aging (cardio)vascular system prone to disease. In this review, we focus on structural mechanisms of arterial stiffening as a major manifestation of vascular aging and its functional implications for the concept of healthy aging.

High fat mass, low muscle mass, and arterial stiffness in a population of free-living healthy subjects: The "al passo con la tua salute" project

INTRODUCTION

A progressive decline in lean body mass and increase in fat mass occur with aging, and result in progressive weakness and impaired mobility; these features are altogether landmarks of the ageing frailty syndrome. High-fat mass and low muscle mass are both associated with an increased risk of cardiovascular events and are supposed to be risk factors for arterial stiffness. Little data analyzing the relationship between body composition and cardio-ankle vascular index (CAVI) are currently available. The main objective of this study was to verify whether low muscle mass and/or high fat mass could be associated with arterial stiffness measured by CAVI.

METHODS

Data are from the cross-sectional assessment of the "Al passo con la tua salute", a clinical study aimed to promote physical function among free-living elderly subjects.After a screening interview and a clinical visit aimed to exclude ineligible persons, 52 volunteers were enrolled in the study. All underwent: clinical examination, physical performance assessment, an interview on lifestyle and dietary habits, and lastly, a blood sample collection after at least 8 hours of fasting.

RESULTS

CAVI was statistically significantly higher in those participants in the highest tertile of distribution for fat mass compared to all other subjects (P = .03). In those participants in the lowest tertile of distribution of muscle mass, compared to all other, CAVI was also statistically significant higher (P = .01) independently of age, sex, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and systolic blood pressure.

CONCLUSIONS

Low muscle mass and high fat mass were landmarks in the frailty model of aging; therefore, it is not inconsistent that both clinical conditions might share with the "aging vessel" a common pathway, probably mediated through signaling network deregulation and/or through alteration of the balance between energy availability and energy demand.

Effect of carbohydrate restriction-induced weight loss on aortic pulse wave velocity in overweight men and women

Increased aortic stiffness, measured by carotid-to-femoral pulse wave velocity (PWV), is an independent predictor of cardiovascular disease, and past data have shown that low-fat and low-energy diets, fed for 8–24 weeks, lower PWV. The purpose of this study was to determine whether a reduction in PWV would be achieved by dietary carbohydrate (CHO) restriction, shown to bring about weight loss over a shorter timeframe. Men (n = 10, age: 41.8 ± 10.2 years, BMI: 34.2 ± 3.0 kg/m2 (mean ± SD)) and women (n = 10, age: 38.6 ± 6.1 years, BMI: 33.5 ± 3.8 kg/m2) with characteristics of insulin resistance and the metabolic syndrome consumed a structured, CHO-restricted diet for 4 weeks (energy deficit, 645 kcal/day). For the whole group, subjects lost 5.4% ± 0.5% (P < 0.001) of body weight and experienced significant reductions in blood pressure (6%–8%), plasma insulin (34%), and triglycerides (34%). PWV was reduced by 6% ± 2% (7.1 ± 0.2 m/s to 6.7 ± 0.2 m/s, P = 0.008) and surprisingly, in women, it fell significantly (from 7.2 ± 0.3 m/s to 6.3 ± 0.3 m/s, P = 0.028), while no changes were observed in men (7.2 ± 0.3 vs. 7.0 ± 0.3 m/s, P = 0.144). This is the first study to demonstrate that weight loss can improve PWV in as little as 4 weeks and that dietary CHO restriction may be an effective treatment for reducing aortic stiffness in women. Future studies are needed to establish the mechanisms by which dietary CHO restriction may confer more cardiovascular benefits to women than to men.

Regaining body weight after weight reduction further increases pulse wave velocity in obese men with metabolic syndrome

Subjects with metabolic syndrome (MetS) or obesity have worse arterial stiffness. However, there have been no studies addressing time-sequential changes in pulse wave velocity (PWV) after weight loss and then regaining weight in obese non-diabetic men with MetS.We prospectively enrolled 40 obese, non-diabetic men with MetS undergoing a 3-month weight reduction program. Another 26 lean and healthy men were recruited for comparisons. Oral glucose tolerance test and brachial ankle (ba) PWV were assessed in study subjects. Eighteen obese non-diabetic MetS and 15 lean control subjects had follow-ups at the 60th month.The body weight of obese MetS decreased from 94.8 ± 7.6 to 86.1 ± 9.0 (N = 18, P < .001) after a 3-month weight reduction program but regained gradually thereafter to 93.6 ± 11.6 kg at the 60th month (P < .001 versus 3rd month). baPWV decreased after weight loss slightly (P = .240) while weight regain significantly increased the baPWV (from 3rd month, 1358 ± 168 to 60th month 1539 ± 264 cm/sec, P < .001). Systolic and diastolic blood pressure increments correlated with the increment of baPWV after weight regain. At the 60th month, lean controls (N = 15) had increases in body weight while their baPWV increased non-significantly. The increments of baPWV after weight regain in obese MetS were significantly higher than the increment of baPWV in lean controls after weight gain.In conclusion, regaining body weight after weight reduction worsened arterial stiffness with significant increase of baPWV in obese non-diabetic MetS.

Opportunities and challenges of behavior change support systems for enhancing habit formation: A qualitative study

The formation of healthy habits is considered to play a fundamental role in health behavior change. A variety of studies on Health Behavior Change Support Systems (HBCSS) have been conducted recently, in which individuals use such systems to influence their own attitudes or behaviors to achieve their personal goals. However, comparatively much less research has been devoted to studying how the users of these systems form habits with the help of HBCSS, or to understanding how to design these systems to support habit formation.

OBJECTIVE

The objective of this article is to study HBCSS user experiences regarding habit formation through an intervention study targeted at establishing a healthier lifestyle. This study also aims to map habit formation stages, as suggested by Lally and Gardner, with the Persuasive System Design (PSD) model. The application domain is the prevention of metabolic syndrome, in which 5% weight loss can significantly reduce the prevalence of the syndrome.

METHODS

This study employs a web-based HBCSS named Onnikka, a lifestyle intervention designed for the prevention of metabolic syndrome for participants who are at risk of developing a metabolic syndrome or are already suffering from it. The system under investigation was designed according to the principles of the PSD model and Behavior Change Support System framework. Lally and Gardner's research on the stages of habit formation were used to study the extent to which the Onnikka system was able to enhance the development of new habits. A total of 43 Onnikka users were interviewed for this study during and after a 52-week intervention period. The research approach employed here was hermeneutics, which leans ontologically toward the social construction of reality, gained through language, consciousness, and shared meaning. In addition, the system's login data and participants' weight measurements were utilized to build an interpretation of the results.

RESULTS

The findings of this study suggest that IT habits appear to have a strong linkage with use adherence, whereas lifestyle habits did not seem to be directly related to the 5% weight loss among study participants. Moreover, habit formation stages provide a possible explanation for why self-monitoring, reminders, and tunneling were perceived as especially valuable features in this study.

CONCLUSIONS

For sustainable weight management, holistic e-health interventions are required, and the PSD model offers a practical approach for designing and developing them. Recognizing the stages of habit formation provides additional valuable guidance for designing systems that help shape an individual's habits.

Adiposity, Change in Adiposity, and Cognitive Decline in Mid- and Late Life

OBJECTIVES

To examine associations between adiposity and adiposity change (loss, stable, gain) and subsequent longitudinal cognitive performance in African Americans in mid and late life.

DESIGN

Cohort study using linear mixed models.

SETTING

Genetic Epidemiology Network of Arteriopathy.

PARTICIPANTS

African-American sibships with hypertension in Jackson, Mississippi (N = 1,108).

MEASUREMENTS

Waist circumference and body mass index (BMI) were measured at two examinations 5 years apart. Stable adiposity was defined as values within 5% of the first measure. A composite cognitive Z-score was derived from individual cognitive test Z-scores at two study visits 6 years apart.

RESULTS

Larger waist circumference was associated with greater rate of cognitive decline during follow-up (beta = -0.0009 per year, P = .001); BMI, change in waist circumference, and change in BMI were not associated with rate of decline. Loss of adiposity in midlife was associated with higher cognitive Z-scores in middle-aged individuals, and loss of adiposity in late life was associated with lower Z-scores in older adults (P = .01 for interaction between waist circumference and age; P = .04 for interaction between BMI and age). Simultaneous inclusion of waist circumference and BMI in the cross-sectional model suggested an association between larger waist circumference and poorer cognitive performance (beta = -0.009, P = .006) and between higher BMI and better cognitive performance (beta = 0.014, P = .06).

CONCLUSION

The results suggested a differential pattern of the relationship between adiposity and cognition according to age (mid- or late life) and regional distribution of adiposity.

The Correlation of Arterial Stiffness with Biophysical Parameters and Blood Biochemistry

INTRODUCTION

Type 2 diabetes presents with numerous macrovascular and microvascular impairments, which in turn lead to various co-morbidities. Vascular co-morbidities can be seen when examining arterial stiffness (AS), which is a predictor for endothelial health and cardiovascular disease risk. Pulse wave analysis (PWA) and pulse wave velocity (PWV) are two tests that are commonly used to measure AS. Currently, disease states and progression are tracked via blood biochemistry. These gold standards in monitoring diabetes are expensive and need optimization.

RESEARCH QUESTION

To investigate which biophysical and biochemical parameters correlated best with AS, which may reduce the number of biochemical tests and biophysical parameter measurements needed to track disease progression.

METHODS

Data from 42 subjects with type 2 diabetes mellitus for ≤10 years, aged 40-70 years, were analyzed at a single time point. We investigated various blood biochemistry, body composition, and AS parameters.

RESULTS

A combination of fat mass and fat-free mass was most associated with PWA over any other parameters. Leptin and high-sensitivity C-reactive protein seem to be the next two parameters that correlate with augmentation index. No other parameters had strong correlations to either PWA or PWV values.

CONCLUSIONS

Body composition methods seemed to be better predictors of type 2 diabetes mellitus patient's vascular disease progression. Our study indicates that body composition measurements may help replace expensive tests. This may have public health and health surveillance implications in countries facing financial challenges.

Effects of an Encapsulated Fruit and Vegetable Juice Concentrate on Obesity-Induced Systemic Inflammation: A Randomised Controlled Trial

Phytochemicals from fruit and vegetables reduce systemic inflammation. This study examined the effects of an encapsulated fruit and vegetable (F&V) juice concentrate on systemic inflammation and other risk factors for chronic disease in overweight and obese adults. A double-blinded, parallel, randomized placebo-controlled trial was conducted in 56 adults aged ≥40 years with a body mass index (BMI) ≥28 kg/m². Before and after eight weeks daily treatment with six capsules of F&V juice concentrate or placebo, peripheral blood gene expression (microarray, quantitative polymerase chain reaction (qPCR)), plasma tumour necrosis factor (TNF)α (enzyme-linked immunosorbent assay (ELISA)), body composition (Dual-energy X-ray absorptiometry (DEXA)) and lipid profiles were assessed. Following consumption of juice concentrate, total cholesterol, low-density lipoprotein (LDL) cholesterol and plasma TNFα decreased and total lean mass increased, while there was no change in the placebo group. In subjects with high systemic inflammation at baseline (serum C-reactive protein (CRP) ≥3.0 mg/mL) who were supplemented with the F&V juice concentrate (n = 16), these effects were greater, with decreased total cholesterol, LDL cholesterol and plasma TNFα and increased total lean mass; plasma CRP was unchanged by the F&V juice concentrate following both analyses. The expression of several genes involved in lipogenesis, the nuclear factor-κB (NF-κB) and 5' adenosine monophosphate-activated protein kinase (AMPK) signalling pathways was altered, including phosphomevalonate kinase (PMVK), zinc finger AN1-type containing 5 (ZFAND5) and calcium binding protein 39 (CAB39), respectively. Therefore, F&V juice concentrate improves the metabolic profile, by reducing systemic inflammation and blood lipid profiles and, thus, may be useful in reducing the risk of obesity-induced chronic disease.

Improved insulin sensitivity, central systolic pressure and inflammatory indicators achieved with minor weight reduction in overweight and obese subjects given education on lifestyle modification

Background: Obesity is a global epidemic disease; lifestyle modification is an approach in the prevention and management of obesity.

Objective: We determined the effects of education on modified lifestyle intervention on arterial stiffness, metabolic and inflammatory markers.

Methods: Twenty-five generally healthy overweight and obese subjects completed nine months education on modified lifestyle intervention at Hospital Universiti Sains Malaysia, Kota Bharu. Subjects were regularly counselled to increase physical activity and modify their diet during intervention. Arterial stiffness was measured noninvasively using carotid femoral pulse wave velocity (PWV) and pulse wave analysis (PWA). Anthropometric measurements, body fat percentage and visceral fat, central and brachial blood pressures, lipid profile, the inflammatory marker high sensitivity C-reactive protein (hsCRP) and insulin sensitivity were also recorded.

Results: After nine months, a significant weight loss of 2.2 kg was observed associated with significant reductions in waist and hip circumference, aortic systolic blood pressure, serum fasting insulin, insulin resistance, and hsCRP levels. Insulin sensitivity was increased, while body fat and visceral fat percentages were marginally reduced (p = 0.058 and p = 0.059). No significant differences were seen in arterial stiffness, fasting plasma glucose and lipid profile.

Conclusion: Education on modified lifestyle intervention improved insulin sensitivity and resistance, reduced hsCRP and aortic systolic blood pressure despite the small weight reduction achieved.

Comparison of High-Protein, Intermittent Fasting Low-Calorie Diet and Heart Healthy Diet for Vascular Health of the Obese

AIM

It has been debated whether different diets are more or less effective in long-term weight loss success and cardiovascular disease prevention among men and women. To further explore these questions, the present study evaluated the combined effects of a high-protein, intermittent fasting, low-calorie diet plan compared with a heart healthy diet plan during weight loss, and weight loss maintenance on blood lipids and vascular compliance of obese individuals.

METHODS

The experiment involved 40 obese adults (men, n = 21; women, n = 19) and was divided into two phases: (a) 12-week high-protein, intermittent fasting, low-calorie weight loss diet comparing men and women (Phase 1) and (b) a 1-year weight maintenance phase comparing high-protein, intermittent fasting with a heart healthy diet (Phase 2). Body weight, body mass index (BMI), blood lipids, and arterial compliance outcomes were assessed at weeks 1 (baseline control), 12 (weight loss), and 64 (12 + 52 week; weight loss maintenance).

RESULTS

At the end of weight loss intervention, concomitant reductions in body weight, BMI and blood lipids were observed, as well as enhanced arterial compliance. No sex-specific differences in responses were observed. During phase 2, the high-protein, intermittent fasting group demonstrated a trend for less regain in BMI, low-density lipoprotein (LDL), and aortic pulse wave velocity than the heart healthy group.

CONCLUSION

Our results suggest that a high-protein, intermittent fasting and low-calorie diet is associated with similar reductions in BMI and blood lipids in obese men and women. This diet also demonstrated an advantage in minimizing weight regain as well as enhancing arterial compliance as compared to a heart healthy diet after 1 year.

Persuasive user experiences of a health Behavior Change Support System: A 12-month study for prevention of metabolic syndrome

BACKGROUND

Obesity has become a severe health problem in the world. Even a moderate 5% weight loss can significantly reduce the prevalence of metabolic syndrome, which can be vital for preventing comorbidities caused by the obesity. Health Behavior Change Support Systems (hBCSS) emphasize an autogenous approach, where an individual uses the system to influence one's own attitude or behavior to achieve his or her own goal. Regardless of promising results, such health interventions technology has often been considered merely as a tool for delivering content that has no effect or value of its own. More research on actual system features is required.

OBJECTIVES

The objective of this study is to describe how users perceive persuasive software features designed and implemented into a support system.

METHODS

The research medium in this study is a web-based information system designed as a lifestyle intervention for participants who are at risk of developing a metabolic syndrome or who are already suffering from it. The system was designed closely following the principles of the Persuasive Systems Design (PSD) model and the Behavior Change Support Systems (BCSS) framework. A total of 43 system users were interviewed for this study during and after a 52 week intervention period. In addition, the system's login data and subjects' Body Mass Index (BMI) measures were used to interpret the results.

RESULTS

This study explains in detail how the users perceived using the system and its persuasive features. Self-monitoring, reminders, and tunneling were perceived as especially beneficial persuasive features. The need for social support appeared to grow along the duration of the intervention. Unobtrusiveness was found to be very important in all stages of the intervention rather than only at the beginning.

CONCLUSIONS

Persuasive software features have power to affect individuals' health behaviors. Through their systematicity the PSD model and the BCSS framework provide effective support for the design and development of technological health interventions. Designers of such systems may choose, for instance, to implement more self-monitoring tools to help individuals to adjust their personal goals with the system's offerings better.

Weight Loss, Dietary Intake and Pulse Wave Velocity

We have recently conducted a meta-analysis to determine the effect of weight loss achieved by an energy-restricted diet with or without exercise, anti-obesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Twenty studies, including 1,259 participants, showed that modest weight loss (8% of the initial body weight) caused a reduction in PWV measured at all arterial segments. However, due to the poor methodological design of the included studies, the results of this meta-analysis can only be regarded as hypothesis generating and highlight the need for further research in this area. In the future, well-designed randomised controlled trials are required to determine the effect of diet-induced weight loss on PWV and the mechanisms involved. In addition, there is observational evidence that dietary components such as fruit, vegetables, dairy foods, sodium, potassium and fatty acids may be associated with PWV, although evidence from well-designed intervention trials is lacking. In the future, the effect of concurrently improving dietary quality and achieving weight loss should be assessed in randomised controlled trials.

Occurrence of increased arterial stiffness in a cohort of adult patients with type 1 diabetes mellitus when compared to normoglycemic controls

The prevalence of cardiovascular risk factors among patients with type 1 diabetes is underestimated. This study was conducted to assess the cardiovascular risk by comparing arterial stiffness in type 1 diabetes with that of controls. Thirty-one type 1 diabetes patients and 31 age- and gender-matched controls were included. The brachial-ankle pulse wave velocity (ba-PWV) was measured using Periscope, a noninvasive device. The ba-PWV was found to be significantly elevated among the patients with diabetes (1177.09 ± 180.1 cm/s) when compared with the controls (1057.99 ± 95.8 cm/s) (P = .003). The ba-PWV showed positive correlation with age (r = .43, P = .014), heart rate (r = .49, P = .005), blood pressure (r = .65, P < .001), and LDL (r = .46, P = .008) among patients with diabetes. Linear regression analysis revealed that diabetes, age, systolic blood pressure (SBP), and BMI were independently associated with ba-PWV (R (2) = .589). On subdividing the diabetes cohort into quintiles for LDL and SBP, a substantial increase in ba-PWV was seen at LDL > 102 mg/dl (1187.8 cm/s to 1364.9 cm/s, P = .09) and SBP > 130 mmHg (1176.1 cm/s to 1369.4 cm/s, P = .03). Arterial stiffness as assessed by ba-PWV is significantly increased among patients with type 1 diabetes compared to healthy controls, independent of traditional cardiovascular risk factors. Early screening for arterial stiffness using a cheap and effective method among patients with SBP > 130 mmHg and LDL > 102 mg/dl may help identify those with heightened cardiovascular risk.

Effects of intensive lifestyle intervention and gastric bypass on aortic stiffness: a 1-year nonrandomized clinical study

OBJECTIVE

To compare the long-term effects of Roux-en-Y gastric bypass (GBS) and intensive lifestyle intervention (ILI) on aortic stiffness.

METHODS

Nonrandomized clinical trial. Aortic stiffness was assessed by carotid-femoral pulse wave velocity (cf PWV) using high-fidelity applanation tonometry.

RESULTS

A total of 159 treatment-seeking morbidly obese patients were included, 82 (54 females) in the GBS-group and 77 (48 females) in the ILI-group. Participants in the GBS-group were younger (42.0 ± 9.9 vs. 46.4 ± 10.5 years), heavier (BMI 45.7 ± 5.3 vs. 42.0 ± 4.9 kg/m(2) ), and had lower systolic pressure (137 ± 19 vs. 145 ± 18 mm Hg) and pulse pressure (57 ± 16 vs. 65 ± 17 mm Hg), all P ≤ 0.006. Mean (SD) cf PWV at baseline was 8.6 ± 1.7 m/s in the GBS-group and 8.6 ± 1.9 m/s in the ILI-group, P = 0.959. At follow-up, mean (95% CI) weight loss was larger in the GBS-group than in the ILI-group -43.3 (-46.0 to -40.7) vs. -12.1 (-14.6 to -9.6) kg, P < 0.001. The mean change in cf PWV was -0.02 (-0.31 to 0.27) m/s in the GBS-group and 0.03 (-0.28 to 0.33) m/s in the ILI-group, both P ≥ 0.412; adjusted between-group difference (ANCOVA) 0.05 (-0.40 to 0.49) m/s, P = 0.836. The adjusted regression analysis showed that weight loss was associated with increased cf PWV in the GBS-group.

CONCLUSIONS

GBS and ILI had no significant long-term effects on aortic stiffness in treatment-seeking morbidly obese individuals.

Impact of central obesity on the estimation of carotid-femoral pulse wave velocity

BACKGROUND

Studies have found that central obesity is associated with higher carotid-femoral pulse wave velocity (PWV). However, traveled distance (TD) measured over the body surface can be substantially overestimated with wider waist circumference (WC). We sought to investigate whether central obesity biases the estimation of PWV and whether this bias explains the association between PWV and different measures of adiposity.

METHODS

Seven hundred eleven participants (49.5% men) from the Baltimore Longitudinal Study of Aging with PWV, anthropometrics, and quantification of different fat depots by computed tomography and dual x-ray absorptiometry were included. TD and relative PWV were estimated with a tape measure over the body surface or linear distances taken from radiological images, unaffected by obesity.

RESULTS

A significant association was found between wider WC and a greater difference between the 2 TD measurements and their respective PWV in both sexes (r ≥ 0.34; P < 0.001). This overestimation bias appeared to be generally higher in women than men (0.27 m/sec for each unit increase in WC; P < 0.0001). When TD estimated over the body surface was used to calculate PWV, greater WC, total body fat, subcutaneous fat, and visceral fat were all associated with higher PWV (P < 0.05 for all). However, when PWV was calculated using TD estimated from radiological images or body height, only the association with visceral fat held significant.

CONCLUSIONS

When TD is measured over the body surface, the role of obesity on PWV is substantially overestimated. After accounting for this bias, PWV was still independently associated with visceral fat but not with other measures of adiposity, confirming its contribution to arterial stiffening.

The effects of aquatic exercise on body composition, physical fitness, and vascular compliance of obese elementary students

The purpose of this study was to investigate the effects of aquatic exercise on body composition, physical fitness, and vascular compliance of obese elementary school students. For the purpose of this study, 20 obese elementary students were selected as subjects. The subjects were then divided into two groups: the swimming group (n= 10) and the control group (n= 10). The subjects were asked to exercise for 60 minutes a day, 3 times a week for 12 weeks with an exercise intensity of 50-70% HRmax. The following results were achieved: first, in terms of body composition, both body fat percentage and fat-free mass showed significant differences within the swimming group. There were also significant differences again in the posttest of difference between the two groups. Second, in terms of changes in physical fitness, there were, again, no significant changes in muscular strength between the two groups. However, muscular endurance, flexibility, and cardiopulmonary endurance showed significant differences in the swimming group's test for difference within groups. Significant differences in both groups for the posttest of differences between groups were also seen. Third, in terms of vascular compliance, there was a significant increase in the right leg for the swimming groups' test of difference within groups, as well as in the posttest of difference between groups.

Increased Aortic Stiffness and Attenuated Lysyl Oxidase Activity in Obesity

Objective—

One potential mechanism through which obesity exerts adverse effects on the vascular system is by increasing aortic stiffness, a change known to be predictive of increased cardiovascular mortality. The aim of this study was to investigate the pathophysiology that links obesity to aortic stiffening.

Approach and Results—

Obese ( ob/ob ) mice were used to examine physical, morphological, and molecular changes in the aorta in response to obesity. ob/ob mice had increased aortic pulse wave velocity and tissue rigidity. ob/ob aorta exhibited decreases of lysyl oxidase (LOX) activity and cross-linked elastin, and increases of elastin fragmentation and elastolytic activity. The aortas of ob/ob mice were surrounded by a significant amount of proinflammatory and pro-oxidative perivascular adipose tissue. In vitro studies revealed that the conditioned medium from differentiated adipocytes or the perivascular adipose tissue of ob/ob mice attenuated LOX activity. Furthermore, inhibition of LOX in wild-type lean mice caused elastin fragmentation and induced a significant increase in pulse wave velocity. Finally, we found that obese humans had stiffer arteries and lower serum LOX levels than do normal-weight humans.

Conclusion—

Our results demonstrated that obesity resulted in aortic stiffening in both humans and mice, and established a causal relationship between LOX downregulation and aortic stiffening in obesity.

Arterial stiffness, lifestyle intervention and a low-calorie diet in morbidly obese patients-a nonrandomized clinical trial

OBJECTIVE

Arterial stiffness is an independent predictor of cardiovascular morbidity and mortality. This study aimed to compare the 7-week effect of a low-calorie diet (LCD) and an intensive lifestyle intervention program (ILI) on arterial stiffness in morbidly obese individuals.

DESIGN AND METHODS

Nonrandomized clinical trial. The LCD provided 900 kcal/day, and participants in the LCD group were instructed to maintain their habitual physical activity level. The ILI included two 90-min supervised training sessions 3 days a week at moderate to high intensity (4-8 METs) and a caloric restriction of 1000 kcal/day.

RESULTS

A total of 179 individuals completed the study, 88 (56 women) in the ILI group and 91 (57 women) in the LCD group. High-fidelity applanation tonometry (Millar(®) , Sphygmocor(®) ) was used to measure carotid-femoral pulse wave velocity (PWV). After adjustment for relevant confounders, the ILI group had a significantly greater reduction in PWV than the LCD group; -0.4 (-0.6, -0.1) m/s, P = 0.004. When compared to the LCD group, the ILI group showed a larger reduction in systolic and diastolic blood pressure -5 (-9, -1) and -5 (-7, -2) mmHg, P = 0.038 and P ≤ 0.001 respectively, whereas no difference was observed regarding pulse pressure, P = 0.661. No significant differences between groups were found regarding the loss of fat mass, P = 0.259, but the loss of muscle mass was larger in the LCD group, 0.8 (0.5, 1.1) kg, P ≤ 0.001.

CONCLUSION

Despite the limitations of a nonrandomized design, our findings indicate that for morbidly obese individuals a moderate caloric restriction combined with aerobic physical exercise is associated with a greater decline in PWV than a LCD alone.

Reduced arterial stiffness after weight loss in obese type 2 diabetes and impaired glucose tolerance: the role of immune cell activation and insulin resistance

Weight loss after bariatric surgery reduces cardiac risk and morbidity. We examined weight loss effects on arterial stiffness in morbidly obese subjects, in relation to cytokines, circulating and subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT)-based immune cells and gene expression. Obese subjects with type 2 diabetes mellitus (T2D) or impaired glucose tolerance (n = 14, mean ± SEM body mass index 42.9 kg/m(2)) underwent 24 weeks' caloric restriction, with gastric banding at 12 weeks. Measures were: arterial augmentation index (AIx), insulin resistance, circulating cytokines, immune cell activation markers, and SAT and VAT cytokine gene expression. Weight loss reduced AIx by 20% (p = 0.007), with falls in s-selectin (p = 0.001) and inter-cellular adhesion molecule (p = 0.04). Improved AIx related to reduced surface expression of the interleukin (IL)-2 receptor on T-lymphocytes (TL-IL2R) and granulocyte adhesion markers (r = 0.59, 0.64, respectively, p < 0.04). Higher VAT expression of interferon-γ and monocyte chemoattractant protein-1 associated with a blunted AIx response. A model of TL-IL2R expression, waist, weight and insulin resistance explained 73% of the variance in AIx reduction (p = 0.005). In morbidly obese dysglycaemic subjects, modest weight loss reduces arterial stiffness, the magnitude of which relates to improved markers of inflammation.

The Influence of Weight Loss on Arterial Stiffness in Obese and Overweight Subjects

Objectives: The Metabolic Syndrome (MetS) and obesity are among the provencauses of vascular dysfunction. The cardio-ankle vascular index (CAVI) wasdeveloped as a method to assess arterial stiffness. The aim of the study was toestablish the influence of weight loss on arterial stiffness parameters. Material and Methods: 135 subjects completed a 6 months standardized life style interventionstudy. Average initial weight was 96.63kg with a BMI of 34.34kg/m2. CAVI and theankle-brachial index (ABI) were measured and body composition was assessed.Some biochemical markers were also determined. Results: The average weightdecreased to 84.61kg, with fat mass loss of 9.6 kg. Mean CAVI decreased from7.92±1.28 to 7.21±1.08. The decrease in CAVI correlates with the total weight andfat loss rather than the speed of weight loss. Conclusions: Our results show thatweight loss can influence arterial stiffness, mainly by decreasing fat tissue mass.

Effects of a high-protein, low-carbohydrate v. high-protein, moderate-carbohydrate weight-loss diet on antioxidant status, endothelial markers and plasma indices of the cardiometabolic profile

There are concerns that weight-loss (WL) diets based on very low carbohydrate (LC) intake have a negative impact on antioxidant status and biomarkers of cardiovascular and metabolic health. Obese men (n 16) participated in a randomised, cross-over design diet trial, with food provided daily, at approximately 8.3 MJ/d (approximately 70 % of energy maintenance requirements). They were provided with two high-protein diets (30 % of energy), each for a 4-week period, involving a LC (4 % carbohydrate) and a moderate carbohydrate (MC, 35 % carbohydrate) content. Body weight was measured daily, and weekly blood samples were collected. On average, subjects lost 6.75 and 4.32 kg of weight on the LC and MC diets, respectively (P < 0.001, SED 0.350). Although the LC and MC diets were associated with a small reduction in plasma concentrations of retinol, vitamin E (α-tocopherol) and β-cryptoxanthin (P < 0.005), these were still above the values indicative of deficiency. Interestingly, plasma vitamin C concentrations increased on consumption of the LC diet (P < 0.05). Plasma markers of insulin resistance (P < 0.001), lipaemia and inflammation (P < 0.05, TNF-α and IL-10) improved similarly on both diets. There was no change in other cardiovascular markers with WL. The present data suggest that a LC WL diet does not impair plasma indices of cardiometabolic health, at least within 4 weeks, in otherwise healthy obese subjects. In general, improvements in metabolic health associated with WL were similar between the LC and MC diets. Antioxidant supplements may be warranted if LC WL diets are consumed for a prolonged period.

Are increased carotid artery pulsatility and resistance indexes early signs of vascular abnormalities in young obese males?

PURPOSE

To provide insight into the factors by which obesity in itself may directly lead to early arterial damage, we aimed to determine early sonographic markers of obesity-related vascular dysfunction in young obese males.

METHODS

Thirty-five young obese males and 23 age-matched healthy male volunteers were recruited into the study. Common carotid artery pulsatility index and resistance index were calculated from blood flow velocities curves obtained by pulsed Doppler ultrasonography.

RESULTS

The mean pulsatility index, resistance index, body mass index, waist circumference, systolic and diastolic blood pressure, homeostasis model assessment for insulin resistance, plasma fasting glucose, insulin, C-peptide, triglycerides, low-density lipoprotein cholesterol, and high-sensitivity C-reactive protein were statistically higher in obese subjects than in healthy controls.

CONCLUSIONS

Our results suggest that depressed vessel compliance and increased vascular resistance are features of young, obese, normotensive subjects independently of and in addition to cardiovascular risk factors. As changes in arterial wall properties may be incipient in young obese subjects, future studies will be required to demonstrate whether early intervention such as diet and exercise in this population can improve vascular functions.

Effect of genetic testing for risk of type 2 diabetes mellitus on health behaviors and outcomes: study rationale, development and design

Abstract

Trial Registration

ClinicalTrials.gov: NCT00849563

Correlation between serum lactadherin and pulse wave velocity and cardiovascular risk factors in elderly patients with type 2 diabetes mellitus

AIMS

This study was carried out with the purpose of investigating the association between serum lactadherin, monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor alpha (TNFα) and carotid-femoral pulse wave velocity (PWV) in elderly patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 105 subjects including 27 T2DM patients without vascular complications (DM), 28 T2DM patients with vascular complications (DC), 25 elderly healthy volunteers (older) and 25 younger healthy volunteers (younger) were recruited into the study. Carotid-femoral PWV was measured using an automatic device. Serum lactadherin, MCP-1 and TNFα were determined by enzyme linked immunosorbent assay.

RESULTS

PWV and lactadherin, MCP-1 and TNFα were significantly higher in DM and DC groups than those of older and younger groups. PWV and lactadherin were higher in older group than those of younger group. Moreover, lactadherin was significantly correlated with MCP-1, TNFα, PWV, HbA1c and 2 h postprandial blood glucose (P2hBG) (P<0.05). In multivariate regression analysis, the independent determinants of lactadherin were HbA1c, P2hBG and age (P<0.05).

CONCLUSIONS

These findings underscore that lactadherin is correlated with poor blood glucose control and diabetic vascular complications.

Economic impact of moderate weight loss in patients with Type 2 diabetes: the Fremantle Diabetes Study

AIM

To assess the change in the cost of diabetes medication attributable to moderate weight loss in patients with Type 2 diabetes.

METHODS

Longitudinal data collected annually from 590 patients participating in the observational, community-based Fremantle Diabetes Study were examined to determine whether moderate weight loss (≥ 5% of initial body weight) was independently associated with diabetes medication cost during 4 years' follow-up.

RESULTS

Overall, the weight of the cohort decreased significantly during 4.3 ± 0.4 years' follow-up by 1.3 ± 6.2 kg (-1.4 ± 7.9% baseline body weight; trend P < 0.001). Moderate weight loss was achieved by 31%. HbA(1c) improved significantly in the group with moderate weight loss compared with the group without moderate weight loss [-4 ± 16 mmol/mol (-0.3 ± 1.5%) vs. 0 ± 17 mmol/mol (0.0 ± 1.5%), P = 0.015]. Mean (bias-corrected 95% confidence intervals) diabetes medication costs were $A820 ($A744-907) during follow-up. As the cost distribution was highly right-skewed and contained zeros, it was square root (√) transformed before multiple linear regression analysis. The most parsimonious model of baseline associates of √(diabetes medication cost) included glycaemic control, diabetes treatment, diabetes duration, BMI, systolic blood pressure, serum HDL cholesterol (negative), taking lipid-lowering medication and age (negative) (adjusted R(2) = 73.6%). After adjusting for these variables, √(diabetes medication cost) was negatively associated with moderate weight loss (P = 0.026). After entering average values for the cohort into the model, the cost of diabetes medications between baseline and fourth review for an average patient with no weight loss was $A752 compared with $A652 for a patient who attained moderate weight loss, a saving of $A100 (-13.3%).

DISCUSSION

These data highlight the economic and clinical benefits of moderate weight loss in Type 2 diabetes.

Lifestyle change diminishes a hypertensive response to exercise in type 2 diabetes

PURPOSE

A hypertensive response to exercise (HRE) is common in patients with type 2 diabetes and is associated with increased left ventricular (LV) mass and mortality. This study aimed to determine whether lifestyle modification would improve exercise blood pressure (BP) and reduce LV mass in patients with type 2 diabetes.

METHODS

One hundred and eighty-five patients with type 2 diabetes were randomized to 1 yr of lifestyle intervention (n=97, mean ± SD age=54.7 ± 11.3 yr, 51% men) or usual care (control; n=88, age=53.8 ± 8.1 yr, 61% men). Brachial BP was measured at rest and during a graded maximal exercise test at baseline and 1 yr. Patients also underwent two-dimensional echocardiography to determine LV dimensions. A subgroup of 61 patients had resting and exercise central BP estimated from radial tonometry. An HRE was defined as a maximal exercise systolic BP of ≥210 mm Hg for men and ≥190 mm Hg for women.

RESULTS

At study entry, there were 101 patients (55%) with an HRE (n=51 controls). Compared with controls, lifestyle intervention significantly reduced the propensity to develop an HRE in those participants who did not have HRE at baseline (29.8% vs 59.5%, P=0.006). However, absolute values of exercise and resting (brachial and central) BP and LV mass were not significantly changed (all P values >0.05). There were significant (all P values <0.05) improvements in V˙O2max, body mass index, plasma glucose, insulin resistance, and HDL cholesterol after lifestyle intervention compared with control.

CONCLUSIONS

Lifestyle intervention significantly attenuates the development of an HRE but does not reduce cardiac size after 1 yr in patients with type 2 diabetes.

Increases in central fat mass and decreases in peripheral fat mass are associated with accelerated arterial stiffening in healthy adults: the Amsterdam Growth and Health Longitudinal Study

BACKGROUND

Central fatness is associated with higher arterial stiffness, a mechanism that may explain adiposity-related increases in cardiovascular disease risk. In contrast, peripheral fat and lean masses may counteract such adverse effects, but evidence of this contention, as derived from longitudinal studies at the general population level, is lacking.

OBJECTIVE

The objective was to investigate the associations between changes in central (ie, trunk) fat mass, peripheral (ie, limbs) fat mass, and lean masses with changes in arterial stiffness.

DESIGN

A longitudinal study in 277 (145 women) healthy adults was conducted. Body composition (dual-energy X-ray absorptiometry) and arterial stiffness estimates (ultrasound imaging) were measured repeatedly at the ages of 36 and 42 y.

RESULTS

Changes (per 10 kg) in trunk fat mass were positively associated and changes in peripheral fat mass were inversely associated with carotid Young's elastic modulus (in 10(3) ⋅ kPa) [β = 0.14 (95% CI: 0.02, 0.25) and -0.16 (-0.30, -0.01), respectively] and carotid-femoral pulse wave velocity (in m/s) [β = 1.54 (0.02, 3.07) and -1.46 (-3.48, 0.56), respectively]. Individuals in whom trunk fat increased and peripheral fat decreased over the 6-y follow-up (33% of the study population) had the steepest increases in these stiffness estimates. Notably, these changes were accompanied by minor increases in body weight, which remained within the limits of the normal range throughout.

CONCLUSIONS

Increases in trunk mass and decreases in peripheral fat mass are associated with accelerated arterial stiffening. These findings emphasize the importance of assessing regional changes in body composition, because it may enable identification of individuals with an unrecognized increased cardiovascular disease risk.

Influence of leptin, adiponectin, and resistin on the association between abdominal adiposity and arterial stiffness

BACKGROUND

Adiposity is associated with arterial stiffness, and both adiposity and arterial stiffness independently predict morbidity and mortality. Because adipocytes account for most adipokine production, the objectives of this study were to examine the influence of adipokines such as leptin, adiponectin, and resistin on the relationship between abdominal adiposity and arterial stiffness.

METHODS

This is a cross-sectional analysis of data from the Baltimore Longitudinal Study of Aging (BLSA). Adiposity was measured as kilograms of abdominal adipose tissue using dual-energy X-ray absorptiometry (DXA). Arterial stiffness was assessed as carotid-femoral pulse wave velocity (PWV). Leptin, adiponectin, and resistin were assayed in fasting serum samples. The influence of adipokines on the relationship between adiposity and arterial stiffness by adipokines was examined using standard mediation pathway analysis.

RESULTS

Among 749 participants ages 26-96 years (mean age 67, 52% men, 27% black), abdominal adiposity was positively associated with PWV (relative ratio (RR) = 1.04, P = 0.02), after adjusting for potential confounders but was attenuated and no longer significant after adjusting for leptin (RR = 0.99, P = 0.77). The relationship between adiposity and PWV was not substantially influenced by adiponectin (RR = 1.03, P = 0.06) or resistin (RR = 1.05, P = 0.010). Leptin (RR = 1.02, P < 0.001), resistin (RR = 0.92, P < 0.0001), and adiponectin (RR = 0.97, P = 0.004), but not abdominal adiposity (RR = 1.00, P = 0.94), retained significant associations with PWV when adjusting for each other and confounders.

CONCLUSIONS

Our findings are consistent with the hypothesis that leptin explains, in part, the observed relationship between abdominal adiposity and arterial stiffness. Adiponectin, leptin, and resistin are independent correlates of PWV.

Arterial destiffening with weight loss in overweight and obese middle-aged and older adults

We tested the hypothesis that weight loss via a hypocaloric diet would reduce arterial stiffness in overweight and obese middle-aged and older adults. Thirty-six individuals were randomly assigned to a weight loss (n=25; age: 61.2+/-0.8 years; body mass index: 30.0+/-0.6 kg/m(2)) or a control (n=11; age: 66.1+/-1.9 years; body mass index: 31.8+/-1.4 kg/m(2)) group. Arterial stiffness was measured via carotid artery ultrasonography combined with applanation tonometry and carotid-femoral pulse wave velocity via applanation tonometry at baseline and after the 12-week intervention. Body weight, body fat, abdominal adiposity, blood pressure, beta-stiffness index, and carotid-femoral pulse wave velocity were similar in the 2 groups at baseline (all P>0.05). Body weight (-7.1+/-0.7 versus -0.7+/-1.1 kg), body fat, and abdominal adiposity decreased in the weight loss group but not in the control group (all P<0.05). Brachial systolic and diastolic blood pressures declined (P<0.05) only in the weight loss group. Central systolic and pulse pressures did not change significantly in either group. beta-Stiffness index (-1.24+/-0.22 versus 0.52+/-0.37 U) and carotid-femoral pulse wave velocity (-187+/-29 versus 15+/-42 cm/s) decreased in the weight loss group but not in the control group (all P<0.05). The reductions in carotid-femoral pulse wave velocity were correlated with reductions in total body and abdominal adiposity (r=0.357-0.602; all P<0.05). However, neither total body nor abdominal adiposity independently predicted reductions in arterial stiffness indices. In summary, our findings indicate that weight loss reduces arterial stiffness in overweight/obese middle-aged and older adults, and the magnitudes of these improvements are related to the loss of total and abdominal adiposity.

Metformin reduces arterial stiffness and improves endothelial function in young women with polycystic ovary syndrome: a randomized, placebo-controlled, crossover trial

CONTEXT

Patients with polycystic ovary syndrome (PCOS) have an increased prevalence of insulin resistance and display subclinical evidence of early cardiovascular disease. Metformin improves insulin sensitivity and circulating markers of cardiovascular risk in patients with PCOS, but it is unclear whether this translates into improvements in vascular function.

OBJECTIVE

Our objective was to evaluate the effects of metformin on arterial stiffness and endothelial function in women with PCOS.

DESIGN AND INTERVENTION

Thirty women with PCOS were assigned to consecutive 12-wk treatment periods of metformin or placebo in a randomized, double-blind, crossover design separated by an 8-wk washout.

MAIN OUTCOME MEASURES

The primary outcome measures were assessments of arterial stiffness [augmentation index (AIx), central blood pressure, and brachial and aortic pulse wave velocity (PWV)] and endothelial function. Anthropometry, testosterone, and metabolic biochemistry (lipids, homeostasis model of assessment for insulin resistance, high-sensitivity C-reactive protein, adiponectin, and plasminogen activator inhibitor-1) were also assessed.

RESULTS

Metformin improved AIx [-6.1%; 95% confidence interval (CI) for the difference -8.5 to -3.5%; P < 0.001], aortic PWV (-0.76 m/sec; 95% CI for the difference -1.12 to -0.4 m/sec; P < 0.001), brachial PWV (-0.73 m/sec; 95% CI for the difference -1.09 to -0.38; P < 0.001), central blood pressure (P < 0.001), and endothelium-dependent (AIx after albuterol; P = 0.003) and endothelium-independent (AIx after nitroglycerin; P < 0.001) vascular responses. Metformin also reduced weight (P < 0.001), waist circumference (P < 0.001), and triglycerides (P = 0.004) and increased adiponectin (P = 0.001) but did not affect testosterone or other metabolic measures.

CONCLUSIONS

Short-term metformin therapy improves arterial stiffness and endothelial function in young women with PCOS.

The role of health behaviors in mediating the relationship between depressive symptoms and glycemic control in type 2 diabetes: a structural equation modeling approach

OBJECTIVES

We investigated the longitudinal association between depressive symptoms and glycemic control (HbA1c) in adults with type 2 diabetes, and the extent to which that association was explained by health behaviors.

METHODS

This study assessed data on 998 adults (aged 51 and above) with type 2 diabetes in the US nationally representative Health and Retirement Study and its diabetes-specific mail survey. Participants' depressive symptoms and baseline health behaviors (exercise, body weight control, and smoking status) were collected in 1998. Follow-up health behaviors and the glycemic control outcome were measured at a 2- and 5-year intervals, respectively.

RESULTS

Nearly one in four of participants (23%) reported moderate or high levels of depressive symptoms at baseline (CES-D score >or=3). Adults with higher levels of depressive symptoms at baseline showed lower scores on baseline and follow-up health behaviors as well as higher HbA1c levels at a 5-year follow-up. Structural equation models (SEM) reveal that health behaviors accounted for 13% of the link between depressive symptoms and glycemic control.

CONCLUSIONS

The long-term relationship between depressive symptoms and glycemic control was supported in the present study. Health behaviors, including exercise, body weight control, and smoking status, explained a sizable amount of the association between depressive symptoms and glycemic control. More comprehensive diabetes self-care behaviors should be examined with available data. Other competing explicators for the link, such as endocrinological process and antidepressant effects, also warrant further examination.

Weight loss, HbA1c reduction, and tolerability of cetilistat in a randomized, placebo-controlled phase 2 trial in obese diabetics: comparison with orlistat (Xenical)

The objective of this multicenter, randomized, double-blind study was to determine the efficacy and safety of cetilistat and orlistat relative to placebo in obese patients with type 2 diabetes, on metformin. Following a 2-week run-in, patients were randomized to placebo, cetilistat (40, 80, or 120 mg three times daily), or orlistat 120 mg t.i.d., for 12 weeks. The primary endpoint was absolute change in body weight from baseline. Secondary endpoints included other measures of obesity and glycemic control. Similar reductions in body weight were observed in patients receiving cetilistat 80 or 120 mg t.i.d. or 120 mg t.i.d. orlistat; these reductions were significant vs. placebo (3.85 kg, P = 0.01; 4.32 kg, P = 0.0002; 3.78 kg, P = 0.008). In the 40 mg t.i.d. and placebo groups, reductions were 2.94 kg, P = 0.958 and 2.86 kg, respectively. Statistically significant reductions in glycosylated hemoglobin (HbA(1c)) were noted. Cetilistat was well tolerated, and showed fewer discontinuations due to adverse events (AEs) than in the placebo and orlistat groups. Discontinuation in the orlistat group was significantly worse than in the 120 mg cetilistat and placebo groups and was entirely due to gastrointestinal (GI) AEs. Treatment with cetilistat 80 or 120 mg t.i.d., or with orlistat 120 mg t.i.d., significantly reduced body weight and improved glycemic control relative to placebo in obese diabetic patients. Cetilistat was well tolerated with the number of discontinuations due to AEs being similar to placebo.

Comparison of two diets of varying glycemic index on carotid subclinical atherosclerosis in obese children

Childhood obesity is associated with an increased carotid intima-media thickness (IMT) and stiffness. Increased carotid wall thickening and rigidity are considered markers of subclinical atherosclerosis. The aim of the present study was to test the effect of two hypocaloric diets of varying glycemic index on weight loss and markers of subclinical atherosclerosis in obese children. Seventy consecutive obese children attending the Outpatient Weight Clinic of the Department of Pediatrics were invited to participate in an intensive dietary protocol. Twenty-six accepted and were randomly assigned to two different groups: the first group followed a hypocaloric low-glycemic index diet and the second a hypocaloric high-glycemic index diet. Anthropometric measures and biochemical tests were performed in all children. Quantitative B-mode ultrasound scans were used to measure intima-media thickness (IMT) and diameters of the common carotid artery. Considering both groups together, at 6 months, body mass index decreased from 28.3 +/- 3.1 to 25.8 +/- 3.3 kg/m(2), systolic blood pressure from 119 +/- 12 to 110 +/- 11 mmHg (P< 0.001), diastolic blood pressure from 78 +/- 8 to 74 +/- 7 mmHg (P< 0.001), IMT from 0.48 +/- 0.05 to 0.43 +/- 0.07 mm (P< 0.001), stiffness from 3.57 +/- 1.04 to 2.98 +/- 0.94 mm (P = 0.002), and high-sensitivity C-reactive protein from 1.5 +/- 0.9 (values log transformed) to 0.4 +/- 1.1 (P < 0.001). No differences were detectable in fasting serum triglycerides, total cholesterol, and high-density lipoprotein cholesterol. Insulin resistance (calculated by the HOmeostatic Model Assessment index [HOMA] score) significantly reduced only in the low-glycemic-index diet group (P < 0.04). In conclusion, this study confirms a benefit of hypocaloric diets on carotid IMT and stiffness in obese children and demonstrates, for the first time, an amelioration of insulin sensitivity in obese children after a low-glycemic index diet. These results justify the advice to obese children to follow a low-glycemic index diet in order to improve their cardiometabolic profile.

Effect of diet-induced weight loss on plasma apelin and cytokine levels in individuals with the metabolic syndrome

BACKGROUND AND AIMS

Adipose tissue is an active endocrine organ that secretes signaling molecules involved in the regulation of insulin sensitivity, food intake and inflammation. Apelin is a peptide secreted by adipose tissue that has been shown to modulate cardiovascular tone in animals. The aim of this study was to measure abdominal fat, blood pressure and circulating apelin, adiponectin, leptin, ghrelin, TNF-alpha and IL-6 levels in patients with the metabolic syndrome after a diet-induced weight loss.

METHODS AND RESULTS

35 obese individuals with the metabolic syndrome underwent an 8-week very-low-calorie diet (VLCD) and a 6-month weight maintenance period (WM) with 120mg orlistat or placebo administered 3 times daily. VLCD and WM (-15.1+/-1.0kg) decreased mean arterial pressure (MAP), insulin, leptin, triglycerides and visceral and subcutaneous adipose tissue. Moreover, adiponectin increased in response to the weight loss. However, the overall changes in plasma apelin, TNF-alpha and IL-6 were non-significant. A correlation between plasma apelin and TNF-alpha was observed at baseline (0.41, p<0.05), and the minor changes in plasma apelin levels were associated with changes in BMI during VLCD and MAP and TNF-alpha during VLCD and WM periods.

CONCLUSION

Despite reductions in BMI, body adiposity, MAP and enhancement of glucose metabolism and adiponectin in response to weight loss, no significant changes in plasma apelin, TNF-alpha and IL-6 were observed. However, apelin significantly correlated with TNF-alpha and MAP. These results suggest that apelin may not be that strongly correlated with the fat mass as an adipokine like the more abundant adipokines adiponectin or leptin and it might be involved in the regulation of inflammation and cardiovascular tone.