Natalie Blanch

Effect of Weight Loss on Pulse Wave Velocity Systematic Review and Meta-Analysis

Objective—To conduct a systematic review and meta-analysis of clinical trials involving adults, to determine the effect of weight loss induced by energy restriction with or without exercise, antiobesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Approach and Results—A systematic search of Pubmed (1966 to 2014), EMBASE (1947 to 2014), MEDLINE (1946 to 2014), and the Cochrane Library (1951 to 2014) was conducted and the reference lists of identified articles were searched to find intervention trials (randomized/nonrandomized) that aimed to achieve weight loss and included PWV as an outcome. The search was restricted to human studies. Two independent researchers extracted the data. Data were analyzed using Comprehensive Meta Analysis version 2 using random effects analysis. A total of 22 studies were included in the qualitative synthesis and 20 studies (3 randomized controlled trials), involving 1259 participants, were included in the meta-analysis. The standardized mean difference for the overall effect of weight loss on PWV measured at all sites was −0.32 (95% confidence interval, −0.41, −0.24; P=0.0001). Carotid femoral pulse wave velocity (standardized mean difference, −0.35; 95% confidence interval, −0.44, −0.26; P=0.0001; 16 studies) and brachial ankle PWV (standardized mean difference, −0.48; 95% confidence interval, −0.78, −0.18; P=0.002; 5 studies) were improved with weight loss. Meta-regression showed that change in blood pressure was a predictor of change in PWV (P<0.01). Conclusion—Modest weight loss (mean 8% of initial body weight) achieved with diet and lifestyle measures improved PWV. The results of this meta-analysis suggest that weight loss may reduce PWV, although future research is required.Objective— To conduct a systematic review and meta-analysis of clinical trials involving adults, to determine the effect of weight loss induced by energy restriction with or without exercise, antiobesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Approach and Results— A systematic search of Pubmed (1966 to 2014), EMBASE (1947 to 2014), MEDLINE (1946 to 2014), and the Cochrane Library (1951 to 2014) was conducted and the reference lists of identified articles were searched to find intervention trials (randomized/nonrandomized) that aimed to achieve weight loss and included PWV as an outcome. The search was restricted to human studies. Two independent researchers extracted the data. Data were analyzed using Comprehensive Meta Analysis version 2 using random effects analysis. A total of 22 studies were included in the qualitative synthesis and 20 studies (3 randomized controlled trials), involving 1259 participants, were included in the meta-analysis. The standardized mean difference for the overall effect of weight loss on PWV measured at all sites was −0.32 (95% confidence interval, −0.41, −0.24; P =0.0001). Carotid femoral pulse wave velocity (standardized mean difference, −0.35; 95% confidence interval, −0.44, −0.26; P =0.0001; 16 studies) and brachial ankle PWV (standardized mean difference, −0.48; 95% confidence interval, −0.78, −0.18; P =0.002; 5 studies) were improved with weight loss. Meta-regression showed that change in blood pressure was a predictor of change in PWV ( P <0.01). Conclusion— Modest weight loss (mean 8% of initial body weight) achieved with diet and lifestyle measures improved PWV. The results of this meta-analysis suggest that weight loss may reduce PWV, although future research is required. # Significance {#article-title-45}

Effect of Weight Loss on Pulse Wave Velocity

Objective—To conduct a systematic review and meta-analysis of clinical trials involving adults, to determine the effect of weight loss induced by energy restriction with or without exercise, antiobesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Approach and Results—A systematic search of Pubmed (1966 to 2014), EMBASE (1947 to 2014), MEDLINE (1946 to 2014), and the Cochrane Library (1951 to 2014) was conducted and the reference lists of identified articles were searched to find intervention trials (randomized/nonrandomized) that aimed to achieve weight loss and included PWV as an outcome. The search was restricted to human studies. Two independent researchers extracted the data. Data were analyzed using Comprehensive Meta Analysis version 2 using random effects analysis. A total of 22 studies were included in the qualitative synthesis and 20 studies (3 randomized controlled trials), involving 1259 participants, were included in the meta-analysis. The standardized mean difference for the overall effect of weight loss on PWV measured at all sites was −0.32 (95% confidence interval, −0.41, −0.24; P=0.0001). Carotid femoral pulse wave velocity (standardized mean difference, −0.35; 95% confidence interval, −0.44, −0.26; P=0.0001; 16 studies) and brachial ankle PWV (standardized mean difference, −0.48; 95% confidence interval, −0.78, −0.18; P=0.002; 5 studies) were improved with weight loss. Meta-regression showed that change in blood pressure was a predictor of change in PWV (P<0.01). Conclusion—Modest weight loss (mean 8% of initial body weight) achieved with diet and lifestyle measures improved PWV. The results of this meta-analysis suggest that weight loss may reduce PWV, although future research is required.Objective— To conduct a systematic review and meta-analysis of clinical trials involving adults, to determine the effect of weight loss induced by energy restriction with or without exercise, antiobesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Approach and Results— A systematic search of Pubmed (1966 to 2014), EMBASE (1947 to 2014), MEDLINE (1946 to 2014), and the Cochrane Library (1951 to 2014) was conducted and the reference lists of identified articles were searched to find intervention trials (randomized/nonrandomized) that aimed to achieve weight loss and included PWV as an outcome. The search was restricted to human studies. Two independent researchers extracted the data. Data were analyzed using Comprehensive Meta Analysis version 2 using random effects analysis. A total of 22 studies were included in the qualitative synthesis and 20 studies (3 randomized controlled trials), involving 1259 participants, were included in the meta-analysis. The standardized mean difference for the overall effect of weight loss on PWV measured at all sites was −0.32 (95% confidence interval, −0.41, −0.24; P =0.0001). Carotid femoral pulse wave velocity (standardized mean difference, −0.35; 95% confidence interval, −0.44, −0.26; P =0.0001; 16 studies) and brachial ankle PWV (standardized mean difference, −0.48; 95% confidence interval, −0.78, −0.18; P =0.002; 5 studies) were improved with weight loss. Meta-regression showed that change in blood pressure was a predictor of change in PWV ( P <0.01). Conclusion— Modest weight loss (mean 8% of initial body weight) achieved with diet and lifestyle measures improved PWV. The results of this meta-analysis suggest that weight loss may reduce PWV, although future research is required. # Significance {#article-title-45}

A systematic review of vascular and endothelial function: Effects of fruit, vegetable and potassium intake

AIM To review the relationships between: 1) Potassium and endothelial function; 2) Fruits and vegetables and endothelial function; 3) Potassium and other measures of vascular function; 4) Fruits and vegetables and other measures of vascular function. DATA SYNTHESIS An electronic search for intervention trials investigating the effect of potassium, fruits and vegetables on vascular function was performed in MEDLINE, EMBASE and the Cochrane Library. Potassium appears to improve endothelial function with a dose of >40 mmol/d, however the mechanisms for this effect remain unclear. Potassium may improve measures of vascular function however this effect may be dependent on the effect of potassium on blood pressure. The effect of fruit and vegetables on endothelial function independent of confounding variables is less clear. Increased fruit and vegetable intake may improve vascular function only in high risk populations. CONCLUSION Increasing dietary potassium appears to improve vascular function but the effect of increasing fruit and vegetable intake per se on vascular function is less clear.

Effect of high potassium diet on endothelial function

BACKGROUND AND AIMS Increased potassium intake is related to reduced blood pressure (BP) and reduced stroke rate. The effect of increased dietary potassium on endothelial function remains unknown. The aim was to determine the effect of increased dietary potassium from fruit and vegetables on endothelial function. METHODS AND RESULTS Thirty five healthy men and women (age 32 ± 12 y) successfully completed a randomised cross-over study of 2 × 6 day diets either high or low in potassium. Flow mediated dilatation (FMD), BP, pulse wave velocity (PWV), augmentation index (AI) and a fasting blood sample for analysis of Intercellular Adhesion Molecule-1 (ICAM-1), E-selectin, asymmetric dimethylarginine (ADMA) and endothelin-1 were taken on completion of each intervention. Dietary change was achieved by including bananas and potatoes in the high potassium and apples and rice/pasta in the low potassium diet. Dietary adherence was assessed using 6 day weighed food diaries and a 24 h urine sample. The difference in potassium excretion between the two diets was 48 ± 32 mmol/d (P = 0.000). Fasting FMD was significantly improved by 0.6% ± 1.5% following the high compared to the low potassium diet (P = 0.03). There were no significant differences in BP, PWV, AI, ICAM-1, ADMA or endothelin-1 between the interventions. There was a significant reduction in E-selectin following the high (Median = 5.96 ng/ml) vs the low potassium diet (Median = 6.24 ng/ml), z = -2.49, P = 0.013. CONCLUSION Increased dietary potassium from fruit and vegetables improves FMD within 1 week in healthy men and women but the mechanisms for this effect remain unclear. CLINICAL TRIAL REGISTRY ACTRN12612000822886.

Postprandial effects of potassium supplementation on vascular function and blood pressure: a randomised cross-over study

BACKGROUND AND AIMS Endothelial dysfunction, as assessed by flow mediated dilatation (FMD) is an early event in atherosclerosis and an independent predictor of cardiovascular events. The effect of potassium supplementation on endothelial function and blood pressure (BP) in the postprandial state is not known. The aim of this study was to assess endothelial function using FMD in healthy volunteers. METHODS AND RESULTS Thirty-two normotensive volunteers received a meal with 36 mmol potassium (High K) and a control 6 mmol potassium (Low K) meal on 2 separate occasions in a randomized order. FMD and BP were measured while participants were fasting and at 30, 60, 90 and 120 min after the meal. There was a postprandial decrease in FMD in both groups. FMD decreased overall less after the High K meal compared to the Low K meal (meal effect p < 0.05). Both meals produced a postprandial decrease in BP at 30 min which returned to baseline levels by 120 min. No significant differences in BP were observed between meals. FMD and systolic BP were negatively correlated at 90 (r = -0.54-0.55, p < 0.01) and 120 min (r = -0.42-0.56, p < 0.01) after both meals. CONCLUSIONS A high potassium meal, which contains a similar amount of potassium as 2.5 serves of bananas, can lessen the postprandial reduction in brachial artery FMD when compared to a low potassium meal.

Effect of sodium and potassium supplementation on vascular and endothelial function: a randomized controlled trial

BACKGROUND It is known that increased potassium and reduced sodium intakes can improve postprandial endothelial function. However, the effect of increasing potassium in the presence of high sodium in the postprandial state is not known. OBJECTIVE We aimed to determine the effect of high potassium and high sodium on postprandial endothelial function as assessed by using flow-mediated dilatation (FMD) and arterial compliance as assessed by using pulse wave velocity (PWV) and central augmentation index (AIx). DESIGN Thirty-nine healthy, normotensive volunteers [21 women and 18 men; mean ± SD age: 37 ± 15 y; BMI (in kg/m(2)): 23.0 ± 2.8] received a meal with 3 mmol K and 65 mmol Na (low-potassium, high-sodium meal (LKHN)], a meal with 38 mmol K and 65 mmol Na [high-potassium, high-sodium meal (HKHN)], and a control meal with 3 mmol K and 6 mmol Na (low-potassium, low-sodium meal) on 3 separate occasions in a randomized crossover trial. Brachial artery FMD, carotid-femoral PWV, central AIx, and blood pressure (BP) were measured while participants were fasting and at 30, 60, 90, and 120 min after meals. RESULTS Compared with the LKHN, the addition of potassium (HKHN) significantly attenuated the postmeal decrease in FMD (P-meal by time interaction < 0.05). FMD was significantly lower after the LKHN than after the HKHN at 30 min (P < 0.01). AIx decreased after all meals (P < 0.05). There were no significant differences in AIx, PWV, or BP between treatments over time. CONCLUSION The addition of potassium to a high-sodium meal attenuates the sodium-induced postmeal reduction in endothelial function as assessed by FMD. This trial was registered at http://www.anzctr.org.au/ as ACTRN12613000772741.

Effect of improving dietary quality on carotid intima media thickness in subjects with type 1 and type 2 diabetes: a 12-mo randomized controlled trial

BACKGROUND People with diabetes are at a heightened risk of cardiovascular disease compared with the general population. To our knowledge, randomized controlled trials investigating the effect of improving dietary quality on carotid intima media thickness, a marker of subclinical atherosclerosis and predictor of cardiovascular disease, have not been conducted in populations with diabetes. OBJECTIVE We aimed to determine whether increasing fruit (+1 serving; 150 g/d), vegetable (+2 servings; 150 g/d), and dairy (+1 serving; 200-250 g/d) intakes slows 12-mo common carotid artery intima media thickness (CCA IMT) progression, compared with a control group continuing to consume their usual diet, in people with type 1 and type 2 diabetes. DESIGN A 12-mo randomized controlled trial was conducted. The primary outcome was mean CCA IMT, measured at baseline and 12 mo, with B-mode ultrasound. Participants in the intervention group received counseling from a dietitian at baseline and 1, 3, 6, and 9 mo, and compliance was measured with a food-frequency questionnaire at baseline, 3 mo, and 12 mo. The control group continued consuming their usual diet. RESULTS In total, 118 participants completed the study. Vegetable (46 g/d; 95% CI: 14, 77 g/d; P < 0.001) and fruit (179 g/d; 95% CI: 119, 239 g/d; P < 0.001) intakes were increased at 3 mo in the intervention group compared with the control group. This increase was not maintained at 12 mo, but intake increased overall in the cohort (fruit, 48 g/d; vegetables, 14 g/d). An increase in dairy consumption was not achieved, but yogurt intake was higher in the intervention group at 3 mo (38 g; 95% CI: 12, 65 g; P < 0.001); this was not maintained at 12 mo. At 12 mo, CCA IMT regressed (mean ± SD: -0.01 ± 0.04 mm; P < 0.001), with a greater effect in the treatment group (mean ± SD: -0.02 ± 0.04 mm compared with -0.004 ± 0.04 mm; P = 0.009). CONCLUSION Improving dietary quality in people with well-controlled type 1 and type 2 diabetes may slow CCA IMT progression. This trial was registered at https://www.anzctr.org.au as ACTRN12613000251729.

Dietary quality in people with type 1 and type 2 diabetes compared to age, sex and BMI matched controls

A case-control analysis involving 98 individuals with diabetes and 98 age, sex and BMI matched controls was conducted to determine dietary quality and adherence to dietary recommendations. Diet quality was comparable and intake of fat, saturated fat, fibre, fruit and vegetables did not meet recommendations in both groups.

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.

Effect of Weight Loss on Pulse Wave VelocitySignificance

Objective—To conduct a systematic review and meta-analysis of clinical trials involving adults, to determine the effect of weight loss induced by energy restriction with or without exercise, antiobesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Approach and Results—A systematic search of Pubmed (1966 to 2014), EMBASE (1947 to 2014), MEDLINE (1946 to 2014), and the Cochrane Library (1951 to 2014) was conducted and the reference lists of identified articles were searched to find intervention trials (randomized/nonrandomized) that aimed to achieve weight loss and included PWV as an outcome. The search was restricted to human studies. Two independent researchers extracted the data. Data were analyzed using Comprehensive Meta Analysis version 2 using random effects analysis. A total of 22 studies were included in the qualitative synthesis and 20 studies (3 randomized controlled trials), involving 1259 participants, were included in the meta-analysis. The standardized mean difference for the overall effect of weight loss on PWV measured at all sites was −0.32 (95% confidence interval, −0.41, −0.24; P=0.0001). Carotid femoral pulse wave velocity (standardized mean difference, −0.35; 95% confidence interval, −0.44, −0.26; P=0.0001; 16 studies) and brachial ankle PWV (standardized mean difference, −0.48; 95% confidence interval, −0.78, −0.18; P=0.002; 5 studies) were improved with weight loss. Meta-regression showed that change in blood pressure was a predictor of change in PWV (P<0.01). Conclusion—Modest weight loss (mean 8% of initial body weight) achieved with diet and lifestyle measures improved PWV. The results of this meta-analysis suggest that weight loss may reduce PWV, although future research is required.Objective— To conduct a systematic review and meta-analysis of clinical trials involving adults, to determine the effect of weight loss induced by energy restriction with or without exercise, antiobesity drugs or bariatric surgery on pulse wave velocity (PWV) measured at all arterial segments. Approach and Results— A systematic search of Pubmed (1966 to 2014), EMBASE (1947 to 2014), MEDLINE (1946 to 2014), and the Cochrane Library (1951 to 2014) was conducted and the reference lists of identified articles were searched to find intervention trials (randomized/nonrandomized) that aimed to achieve weight loss and included PWV as an outcome. The search was restricted to human studies. Two independent researchers extracted the data. Data were analyzed using Comprehensive Meta Analysis version 2 using random effects analysis. A total of 22 studies were included in the qualitative synthesis and 20 studies (3 randomized controlled trials), involving 1259 participants, were included in the meta-analysis. The standardized mean difference for the overall effect of weight loss on PWV measured at all sites was −0.32 (95% confidence interval, −0.41, −0.24; P =0.0001). Carotid femoral pulse wave velocity (standardized mean difference, −0.35; 95% confidence interval, −0.44, −0.26; P =0.0001; 16 studies) and brachial ankle PWV (standardized mean difference, −0.48; 95% confidence interval, −0.78, −0.18; P =0.002; 5 studies) were improved with weight loss. Meta-regression showed that change in blood pressure was a predictor of change in PWV ( P <0.01). Conclusion— Modest weight loss (mean 8% of initial body weight) achieved with diet and lifestyle measures improved PWV. The results of this meta-analysis suggest that weight loss may reduce PWV, although future research is required. # Significance {#article-title-45}