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1.
The effect of grape (Vitis vinifera) seed extract supplementation on flow-mediated dilation, blood pressure, and heart rate: A systematic review and meta-analysis of controlled trials with duration- and dose-response analysis.
Foshati, S, Nouripour, F, Sadeghi, E, Amani, R
Pharmacological research. 2022;:105905
Abstract
The objective of this systematic review and meta-analysis of controlled trials was to assess the long-term effect of grape seed extract (GSE) supplementation on flow-mediated dilation (FMD), systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) in adults. Web of Science, Scopus, Medline, Cochrane Library, and Google Scholar were searched up to May 24, 2021. Nineteen trials were included in this study. Weighted mean difference (WMD) and 95% confidence interval (CI) were calculated using a random-effects model. GSE supplementation significantly reduced DBP (WMD: -2.20 mmHg, 95% CI: -3.79 to -0.60, I2 = 88.8%) and HR (WMD: -1.25 bpm, 95% CI: -2.32 to -0.19, I2 = 59.5%) but had no significant effects on FMD (WMD: 1.02%, 95% CI: -0.62 to 2.66, I2 = 92.0%) and SBP (WMD: -3.55 mmHg, 95% CI: -7.59 to 0.49, I2 = 97.4%). Subgroup analysis revealed that the dose and duration of GSE administration and the characteristics of study participants could be sources of between-study heterogeneity. Significant non-linear relationships were found between DBP and the duration of GSE supplementation (P = 0.044) and its dose (P = 0.007). In conclusion, GSE may be beneficial for individuals with or at risk of cardiovascular disease because it may have hypotensive and HR-lowering properties.
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2.
The effect of high Intensity interval training versus moderate intensity continuous training on arterial stiffness and 24h blood pressure responses: A systematic review and meta-analysis.
Way, KL, Sultana, RN, Sabag, A, Baker, MK, Johnson, NA
Journal of science and medicine in sport. 2019;(4):385-391
Abstract
OBJECTIVES Greater arterial stiffness and poor 24h blood pressure (BP) are recognized as indicators of poor cardiovascular health. Evidence has shown that high intensity interval training (HIIT) may be a superior alternative to moderate intensity continuous training (MICT) for improving cardiovascular disease risk factors such as cardiorespiratory fitness and vascular function. However, there are limited data comparing the effect of HIIT to MICT on central arterial stiffness and/or 24h BP response. The purpose of this study was to compare HIIT versus MICT on central arterial stiffness and 24h BP outcomes by systematic review and meta-analysis. DESIGN A systematic review and meta-analysis was conducted. METHODS Eligible studies were exercise training interventions (≥4weeks) that included both HIIT and MICT and reported central arterial stiffness, as measured by pulse wave velocity and augmentation index and/or 24h BP outcome measures. RESULTS HIIT was found to be superior to MICT for reducing night-time diastolic BP (ES: -0.456, 95% CI: -0.826 to -0.086mmHg; P=0.016). A near-significant greater reduction in daytime systolic (ES: -0.349, 95% CI: -0.740 to 0.041mmHg; p=0.079) and diastolic BP was observed with HIIT compared to MICT (ES: -0.349, 95% CI: -0.717 to 0.020mmHg; p=0.063). No significant difference was found for other BP responses or arterial stiffness outcomes. CONCLUSIONS HIIT leads to a superior reduction in night-time diastolic BP compared to MICT. Furthermore, a near-significant greater reduction in daytime BP was found with HIIT compared to MICT. No significant difference was observed for changes to central arterial stiffness between HIIT and MICT.
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3.
Monitoring Athletic Training Status Through Autonomic Heart Rate Regulation: A Systematic Review and Meta-Analysis.
Bellenger, CR, Fuller, JT, Thomson, RL, Davison, K, Robertson, EY, Buckley, JD
Sports medicine (Auckland, N.Z.). 2016;(10):1461-86
Abstract
BACKGROUND Autonomic regulation of heart rate (HR) as an indicator of the body's ability to adapt to an exercise stimulus has been evaluated in many studies through HR variability (HRV) and post-exercise HR recovery (HRR). Recently, HR acceleration has also been investigated. OBJECTIVE The aim of this systematic literature review and meta-analysis was to evaluate the effect of negative adaptations to endurance training (i.e., a period of overreaching leading to attenuated performance) and positive adaptations (i.e., training leading to improved performance) on autonomic HR regulation in endurance-trained athletes. METHODS We searched Ovid MEDLINE, Embase, CINAHL, SPORTDiscus, PubMed, and Academic Search Premier databases from inception until April 2015. Included articles examined the effects of endurance training leading to increased or decreased exercise performance on four measures of autonomic HR regulation: resting and post-exercise HRV [vagal-related indices of the root-mean-square difference of successive normal R-R intervals (RMSSD), high frequency power (HFP) and the standard deviation of instantaneous beat-to-beat R-R interval variability (SD1) only], and post-exercise HRR and HR acceleration. RESULTS Of the 5377 records retrieved, 27 studies were included in the systematic review and 24 studies were included in the meta-analysis. Studies inducing increases in performance showed small increases in resting RMSSD [standardised mean difference (SMD) = 0.58; P < 0.001], HFP (SMD = 0.55; P < 0.001) and SD1 (SMD = 0.23; P = 0.16), and moderate increases in post-exercise RMSSD (SMD = 0.60; P < 0.001), HFP (SMD = 0.90; P < 0.04), SD1 (SMD = 1.20; P = 0.04), and post-exercise HRR (SMD = 0.63; P = 0.002). A large increase in HR acceleration (SMD = 1.34) was found in the single study assessing this parameter. Studies inducing decreases in performance showed a small increase in resting RMSSD (SMD = 0.26; P = 0.01), but trivial changes in resting HFP (SMD = 0.04; P = 0.77) and SD1 (SMD = 0.04; P = 0.82). Post-exercise RMSSD (SMD = 0.64; P = 0.04) and HFP (SMD = 0.49; P = 0.18) were increased, as was HRR (SMD = 0.46; P < 0.001), while HR acceleration was decreased (SMD = -0.48; P < 0.001). CONCLUSIONS Increases in vagal-related indices of resting and post-exercise HRV, post-exercise HRR, and HR acceleration are evident when positive adaptation to training has occurred, allowing for increases in performance. However, increases in post-exercise HRV and HRR also occur in response to overreaching, demonstrating that additional measures of training tolerance may be required to determine whether training-induced changes in these parameters are related to positive or negative adaptations. Resting HRV is largely unaffected by overreaching, although this may be the result of methodological issues that warrant further investigation. HR acceleration appears to decrease in response to overreaching training, and thus may be a potential indicator of training-induced fatigue.
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4.
Impact of Acute Energy Drink Consumption on Blood Pressure Parameters: A Meta-analysis.
Shah, SA, Chu, BW, Lacey, CS, Riddock, IC, Lee, M, Dargush, AE
The Annals of pharmacotherapy. 2016;(10):808-15
Abstract
OBJECTIVE Hospitalizations associated with energy drinks have increased in the past decade. Whereas energy drinks are suspected to cause hemodynamic effects, the magnitude of risk remains controversial. We evaluated the effects of acute energy drink consumption on systolic and diastolic blood pressure (SBP and DBP) and heart rate (HR). DATA SOURCES A search in PubMed, Cumulative Index of Nursing and Allied Health Literature, and Cochrane database through December 31, 2015, was performed. STUDY SELECTION AND DATA EXTRACTION Prospective clinical studies assessing the effects of commercially available energy drinks on BP and HR were included. A weighted mean change from baseline was calculated using the DerSimonian and Laird random-effects model for all end points. DATA SYNTHESIS In all, 15 studies were included, encompassing a total of 340, 322, and 340 individuals for SBP, DBP, and HR, respectively. SBP and DBP increased significantly by 4.44 mm Hg (95% CI = 2.71 to 6.17; Cochrane Q P = 0.001) and 2.73 mm Hg (95% CI = 1.52 to 3.95; Cochrane Q P = 0.050), respectively. HR changed nonsignificantly by 0.80 beats per minute (95% CI = -1.26 to 2.87; Cochrane Q P < 0.001). The largest change in SBP was seen with drinks administering ≥200 mg of caffeine (6.44 mm Hg, 95% CI = 4.62 to 8.27). CONCLUSIONS Our results indicate that acute consumption of caffeinated energy drinks significantly raises SBP and DBP. Further investigation of the ingredients in energy drinks and the impact of chronic energy drink consumption is warranted.
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5.
Resting heart rate and risk of incident heart failure: three prospective cohort studies and a systematic meta-analysis.
Khan, H, Kunutsor, S, Kalogeropoulos, AP, Georgiopoulou, VV, Newman, AB, Harris, TB, Bibbins-Domingo, K, Kauhanen, J, Gheorghiade, M, Fonarow, GC, et al
Journal of the American Heart Association. 2015;(1):e001364
Abstract
BACKGROUND The relationship between resting heart rate (RHR) and incident heart failure (HF) has been questioned. METHODS AND RESULTS RHR was assessed at baseline in 7073 participants in 3 prospective cohorts (Cardiovascular Health Study, Health ABC study and Kuopio Ischemic Heart Disease Study) that recorded 1189 incident HF outcomes during 92 702 person-years of follow-up. Mean age of participants was 67 (9.9) years and mean RHR was 64.6 (11.1) bpm. Baseline RHR correlated (P<0.001) positively with body mass index (r=0.10), fasting glucose (r=0.18), and C-reactive protein (r=0.20); and inversely with serum creatinine (r=-0.05) and albumin (r=-0.05). Baseline RHR was non-linearly associated with HF risk. The age and sex-adjusted hazard ratio for HF comparing the top (>72 bpm) versus the bottom (<57 bpm) quartile of baseline RHR was 1.48 (95% confidence interval [CI] 1.26 to 1.74) and was modestly attenuated (1.30, 95% CI 1.10 to 1.53) with further adjustment for body mass index, history of diabetes, hypertension, smoking status, serum creatinine, and left ventricular hypertrophy. These findings remained consistent in analyses accounting for incident coronary heart disease, excluding individuals with prior cardiovascular events, or those taking beta-blockers; and in subgroups defined by several individual participant characteristics. In a pooled random effects meta-analysis of 7 population-based studies (43 051 participants and 3476 HF events), the overall hazard ratio comparing top versus bottom fourth of RHR was 1.40 (95% CI: 1.19 to 1.64). CONCLUSIONS There is a non-linear association between RHR and incident HF. Further research is needed to understand the physiologic foundations of this association.
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6.
Losmapimod concentration-QT relationship in healthy volunteers: meta-analysis of data from six clinical trials.
Yang, S, Beerahee, M
European journal of clinical pharmacology. 2013;(6):1261-7
Abstract
PURPOSE The objective of this work was to describe the losmapimod concentration-QT relationship using meta-analysis of data from clinical trials with healthy volunteers and to evaluate the covariates that have significant impact on the QT prolongation. METHODS Losmapimod plasma concentration and QT interval data were collected from six early clinical studies with healthy volunteers. The electrocardiograms (ECGs) were collected at baseline and at a number of post-dose time points (losmapimod or placebo). The population pharmacokinetic/pharmacodynamic (PK/PD) modelling approach was applied to investigate the relationship between losmapimod concentration and QT prolongation. RESULTS The dataset for analysis comprised 190 healthy adults who took at least one dose of losmapimod or placebo. Of the 2,494 QT observations collected, 1,532 observations had matched QT and losmapimod plasma concentration data. Population PK/PD analyses indicated that the model with the individual heart rate correction factor (α) fitted the data better than those using fixed α (0.33 for Fridericia's correction or 0.5 for Bazett's correction) and that there was no relationship between losmapimod concentration and QT interval. Female volunteers had about a 3 % higher QT interval at baseline than the male volunteers. No other covariates had a significant effect on the QT interval. CONCLUSIONS It is appropriate to apply population PK/PD analysis to investigate the effect of drug concentration on QT prolongation. Our meta-analysis of healthy volunteer data indicated no relationship between systemic losmapimod concentration and QT interval in healthy volunteers.
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7.
Do antioxidant vitamins have an anti-arrhythmic effect following cardiac surgery? A meta-analysis of randomised controlled trials.
Harling, L, Rasoli, S, Vecht, JA, Ashrafian, H, Kourliouros, A, Athanasiou, T
Heart (British Cardiac Society). 2011;(20):1636-42
Abstract
BACKGROUND Postoperative atrial fibrillation (POAF) affects approximately 30% of patients undergoing elective cardiac surgery. While its pathogenesis is multifactorial, increasing evidence supports a role for oxidative stress in the electrophysiological remodelling associated with AF. Although prophylactic antioxidants appear to be a potentially attractive pharmacotherapy, there is still uncertainty regarding their efficacy. This study aims to provide a quantitative summary of the current evidence surrounding antioxidant vitamins and POAF prevention. METHODS A systematic literature review identified five randomised controlled trials incorporating 567 patients (n = 284 antioxidant, n = 283 control). These were meta-analysed using random effects modelling. Heterogeneity, subgroup analysis, quality scoring and risk of bias were assessed. Primary endpoints were the incidence of POAF and all-cause arrhythmia. Secondary endpoints were length of stay in the intensive care unit (ITU) and length of hospital stay. RESULTS Vitamins C and E significantly reduced the incidence of POAF (OR 0.43, 95% CI 0.21 to 0.89) and all-cause arrhythmia (OR 0.54, 95% CI 0.29 to 0.99) compared with controls. A significant reduction in both ITU stay (weighted mean difference (WMD) -0.44, 95% CI -0.70 to -0.17) and hospital stay (WMD -1.11, 95% CI -1.70 to -0.52) was also seen in the antioxidant group, without significant heterogeneity. CONCLUSIONS The prophylactic use of vitamins C and E may significantly reduce the incidence of POAF and all-cause arrhythmia following cardiac surgery. However, the overall quality of current studies is poor and further research should focus on adequately powered randomised controlled trials that standardise AF reporting, antioxidant protocol and the use of concomitant agents. Cost analysis should be considered to establish the potential economic benefit of antioxidant vitamin prophylaxis in POAF.
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8.
HR index--a simple method for the prediction of oxygen uptake.
Wicks, JR, Oldridge, NB, Nielsen, LK, Vickers, CE
Medicine and science in sports and exercise. 2011;(10):2005-12
Abstract
PURPOSE Energy expenditure measured in METs is widely used in cardiovascular medicine, exercise physiology, and nutrition assessment. However, measurement of METs requires complex equipment to determine oxygen uptake. A simple method to predict oxygen uptake on the basis of HR measurements without requirement for gas analysis, movement-recording devices, or exercise equipment (treadmills, cycle ergometers) would enable a simple prediction of energy expenditure. The purpose of this study was to determine whether HR can be used to accurately predict oxygen uptake. METHODS Published studies that reported a measured resting HR (HR(rest)), a measured activity HR (HR(absolute)), and a measured oxygen uptake (mL O(2)·kg(-1)·min(-1)) associated with the HR(absolute) were identified. A total of 220 data sets were extracted from 60 published exercise studies (total subject cohort = 11,257) involving a diverse range of age, pathophysiology, and the presence/absence of β-blocker therapy. Net HR (HR(net) = HR(absolute) - HR(rest)) and HR index (HR(index) = HR(absolute)/HR(rest)) were calculated from the HR data. A regression analysis of oxygen uptake (expressed as METs) was performed against HR(absolute), HR(net), and HR(index). RESULTS Statistical models for the relationship between METs and the different HR parameters (HR(absolute), HR(net), and HR(index)) were developed. A comparison between regression analyses for the models and the actual data extracted from the published studies demonstrated that the best fit model was the regression equation describing the relationship between HR(index) and METs. Subgroup analyses of clinical state (normal, pathology), testing device (cycle ergometer, treadmill), test protocol (maximal, submaximal), gender, and the effect of β-blockade were all consistent with combined data analysis, demonstrating the robustness of the equation. CONCLUSIONS HR(index) can be used to predict energy expenditure with the equation METs = 6HR(index) - 5.
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9.
Gender and age effects on the ambulatory blood pressure and heart rate responses to antihypertensive therapy.
White, WB, Johnson, MF, Black, HR, Elliott, WJ, Sica, DA
American journal of hypertension. 2001;(12):1239-47
Abstract
BACKGROUND The aim of this study was to assess potential differences in the 24-h antihypertensive response to treatment with the controlled-onset, extended-release (COER) calcium antagonist, verapamil in men versus women and older versus younger patients with hypertension. METHODS Meta-analyses were performed of three prospective randomized, double-blind, placebo-controlled trials with COER-verapamil in patients with mid-stage I to stage III essential hypertension. The trials were conducted at medical clinics in the US and Canada in patients with a mean office diastolic blood pressure (BP) of 95 to 115 mm Hg on 2 consecutive weeks and a mean daytime diastolic BP >90 mm Hg. Patients were randomized to treatment with 180 to 540 mg/day of COER-verapamil (N = 273) or placebo (N = 125). Changes from baseline in ambulatory BP and heart rate after COER-verapamil were compared in men versus women and in older versus younger patients. RESULTS Treatment with COER-verapamil caused significant reductions in 24-h and early-morning systolic and diastolic BP in all of the subpopulations as compared with placebo (P < .001). COER-verapamil induced a greater reduction in both 24-h systolic (-15.1 v -10.0 mm Hg; P < .001) and diastolic (-10.4 v -8.2 mm Hg; P = .003) BP in women compared with men. Older patients showed a greater mean reduction in 24-h diastolic BP (-10.2 v -8.2 mm Hg; P < .05) and heart rate (-5.7 v -4.4 beats/min; P < .05) compared with younger patients. Side effects were similar in all of the COER-verapamil treatment groups. CONCLUSIONS Both gender and age were significant determinants of the response to COER-verapamil. The antihypertensive effect of verapamil is greater in women than in men and in older patients compared with younger patients.
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10.
Heart rate-lowering and -regulating effects of once-daily sustained-release diltiazem.
Boden, WE, Vray, M, Eschwege, E, Lauret, D, Scheldewaert, R
Clinical cardiology. 2001;(1):73-9
Abstract
BACKGROUND Epidemiologic evidence suggests that an elevated heart rate (HR) is an adverse and independent prognostic factor in arterial hypertension and other cardiovascular diseases. Although diltiazem is characterized as an HR-lowering calcium antagonist, no studies have quantified the magnitude of HR changes in patients with angina or hypertension. HYPOTHESIS The study was undertaken to explore the magnitude of proportional HR reduction at varying levels of resting HR with the sustained-release formulation of diltiazem (SR diltiazem) at the usual clinical doses of 200 or 300 mg once daily. METHODS This meta-analysis was conducted on six comparative double-blind studies including 771 patients with angina or hypertension in which SR diltiazem 200-300 mg once daily was compared either with placebo or with other agents known not to influence HR (angiotensin-converting enzyme inhibitors, diuretics). Sustained-release diltiazem decreases elevated baseline HR, with an increasing effect at higher initial rates. RESULTS Multiple comparisons by baseline HR category showed a significant difference between both groups for baseline HR of 74-84 beats/min and > or = 85 beats/min (p = 0.001). Sustained-release diltiazem had no significant HR-decreasing effect on baseline HR < or =74 beats/min but appears to have a genuine regulating effect on HR: it reduces tachycardia without inducing excessive bradycardia. These findings are in contrast to those with dihydropyridine calcium antagonists, which tend to increase HR and have been associated with an adverse outcome in acute cardiovascular conditions. At the same time, there is evidence to suggest that HR-lowering calcium-channel blockers decrease cardiovascular event rates following myocardial infarction. CONCLUSION When calcium antagonists are indicated for use in patients with angina or hypertension, an HR-lowering agent, that is, diltiazem rather than dihydropyridine, should be recommended.