Effects of Vitamin D Supplementation on Central Hemodynamic Parameters and Autonomic Nervous System in Obese or Overweight Individuals. / Efeitos da Suplementação de Vitamina D sobre Parâmetros Hemodinâmicos Centrais e Sistema Nervoso Autônomo em Indivíduos com Obesidade ou Sobrepeso.

BACKGROUND: Previous studies have been inconsistent in demonstrating beneficial cardiovascular effects of vitamin D supplementation. OBJECTIVE: To evaluate the effects of vitamin D3 supplementation on central hemodynamic parameters and autonomic activity in obese/overweight individuals with low vitamin D levels (<30ng/dl). METHODS: Adults 40-65 years old with body mass index ≥25<40 kg/m2 were enrolled in this prospective, randomized, double-blind clinical trial (NCT05689632). Central hemodynamics was assessed using the oscillometric method (Mobil-O-Graph®), and heart rate variability using a Polar heart rate monitor (Kubios® software). Patients (n=53) received a placebo in the control group (CO, n=25) or vitamin D3 (VD, n=28) 7000 IU/day, and were evaluated before (W0) and after 8 weeks (W8) with a significance level of 0.05. RESULTS: The groups were homogeneous regarding age (51±6 vs 52±6 years, p=0.509) and vitamin D levels (22.8±4.9 vs 21.7±4.5ng/ml, p=0.590). At W8, the VD group had significantly higher levels of vitamin D (22.5 vs 35.6ng/ml, p<0.001). Only the VD group showed a significant reduction in systolic blood pressure (SBP; 123±15 vs 119±14mmHg, p=0.019) and alkaline phosphatase (213±55 vs 202±55mg/dl, p=0.012). The CO group showed an increase in augmentation pressure (AP: 9 vs 12 mmHg, p=0.028) and augmentation index (AIx: 26 vs 35%, p=0.020), which was not observed in the VD group (AP: 8 vs 8 mmHg, AIx: 26 vs 25%, p>0.05). VD group showed an increase in the parasympathetic nervous system index (PNSi) (-0.64±0.94 vs -0.16±1.10, p=0.028) and the R-R interval (866±138 vs 924±161 ms, p= 0.026). CONCLUSION: In this sample, eight weeks of daily vitamin D supplementation resulted in an improvement in blood pressure levels and autonomic balance.

FUNDAMENTO: Estudos prévios têm sido inconsistentes em demonstrar efeitos cardiovasculares benéficos da suplementação de vitamina D. OBJETIVO: Avaliar efeitos da suplementação de vitamina D3 sobre parâmetros hemodinâmicos centrais e atividade autonômica em indivíduos obesos/sobrepeso e baixos níveis de vitamina D (<30ng/dl). MÉTODOS: Ensaio clínico prospectivo, randomizado, duplo-cego (NCT05689632), adultos 40-65 anos com índice de massa corporal ≥25<40 kg/m2. Hemodinâmica central avaliada por método oscilométrico (Mobil-O-Graph®), variabilidade da frequência cardíaca utilizando frequencímetro Polar (software Kubios®). Os pacientes (n=53) receberam placebo no grupo controle (CO, n=25) ou vitamina D3 (VD, n=28) 7000 UI/dia, avaliados antes (S0) e após 8 semanas (S8) com nível de significância de 0,05. RESULTADOS: Os grupos foram homogêneos na idade (51±6 vs. 52±6 anos, p=0,509) e níveis de vitamina D (22,8±4,9 vs. 21,7±4,5ng/ml, p=0,590). Na S8, o grupo VD apresentou níveis significativamente maiores de vitamina D (22,5 vs. 35,6ng/ml, p<0,001). Apenas o grupo VD mostrou redução significativa da pressão arterial sistólica (PAS; 123±15 vs. 119±14mmHg, p=0,019) e fosfatase alcalina (213±55 vs. 202±55mg/dl, p=0,012). O grupo CO mostrou elevação da pressão de aumento (AP: 9 vs. 12mmHg, p=0,028) e do índice de incremento (Aix: 26 vs. 35%, p=0,020), o que não foi observado no grupo VD (AP: 8 vs. 8mmHg, Aix: 26 vs. 25%, p>0,05). Grupo VD apresentou aumento no índice do sistema nervoso (iSN) parassimpático (-0,64±0,94 vs. -0,16±1,10, p=0,028) e no intervalo R-R (866±138 vs. 924±161ms, p=0,026). CONCLUSÃO: Nesta amostra, a suplementação diária de vitamina D durante oito semanas resultou em melhora dos níveis pressóricos, parâmetros hemodinâmicos centrais e do equilíbrio autonômico.

Arterial Stiffness Associated with Sympathetic Hyperactivity in Obese Individuals with Moderate to Severe Obstructive Sleep Apnea.

INTRODUCTION: Obstructive Sleep Apnea (OSA) is a chronic disorder associated with several risk factors, and increased Body Mass Index (BMI) and waist circumference are correlated with it is severity. AIM: To evaluate vascular function, central hemodynamics, and autonomic modulation in obese individuals with moderate and severe OSA. METHODS: Individuals of both sexes, aged 40-70 years and BMI ≥ 30 and < 40 kg/m2, were submitted to assessment of heart rate variability, endothelial function by flow-mediated dilatation, central parameters by oscillometry and carotid ultrasound. The sleep study was performed through a portable home sleep test device (WatchPAT). RESULTS: Patients (n = 76) were divided according to Apnea-Hypopnea Index (AHI): absent-mild group (AHI < 15 events/h, n = 30) and Moderate-Severe (MS) group (AHI ≥ 15 events/h, n = 46). The Low/High Frequency (LF/HF) ratio (0.81 ± 0.48 vs 1.39 ± 1.08 ms2, p = 0.035), Pulse Wave Velocity (PWV; 6.9 ± 0.7 vs 7.7 ± 1.6m/s, p = 0.004), vascular age (48 ± 6 vs 53 ± 9 years, p = 0.05) and mean intima-media thickness (0.59 ± 0.08 vs 0.66 ± 0.13 mm, p = 0.011) were significantly higher in the MS group. AHI was significantly correlated with PWV (r = 0.26, p = 0.024) and LF/HF ratio (r = 0.40, p < 0.001). Only in the MS group, PWV was significantly correlated with SD2/SD1 ratio (r = 0.611, p ≤ 0.001), and flow-mediated dilation with central systolic blood pressure (r = 0.364, p = 0.018), even after adjustment for age and sex. CONCLUSION: In this sample of obese individuals, moderate to severe OSA was associated with sympathetic hyperactivity and evidence of accelerated vascular aging with arterial stiffness and subclinical atherosclerosis.

Early Vascular Aging in Obese Individuals with Low Cardiovascular Health.

INTRODUCTION: The American Heart Association updated the original recommendations for cardiovascular health (CVH) promotion, defining the Life's Essential 8 (L8). AIM: the aim of this cross-sectional study was to compare vascular function, central hemodynamics and autonomic modulation in obese individuals with low and moderate CVH-L8. METHODS: Both sexes, aged 40-70 years and Body Mass Index ≥ 30 and < 40 kg/m2, were submitted to anthropometric and biochemical evaluation, assessment of heart rate variability, endothelial function by flow-mediated dilatation (FMD) and central parameters by oscillometry. The CVH-L8 score was determined using the eight metrics defined in the new classification. RESULTS: Patients (n = 82) were divided according to CVH-L8 classification: moderate group (score CVH-L8 ≥ 50 ≤ 79 points, n = 47) and low group (score CVH-L8 ≤ 49 points, n = 35). Peripheral (119 ± 10 vs 125 ± 15 mmHg, p = 0.048) and central (111 ± 10 vs 118 ± 15 mmHg; p = 0.016) systolic blood pressures and pulse wave velocity (PWV) adequacy (- 0.08 ± 0.34 vs 0.15 ± 0.42 m/s, p = 0.008) were significantly higher in low CVH-L8 group. Brachial FMD (9.24 ± 5.41 vs 6.79 ± 4.74%, p = 0.043) were lower in this same group. Only in the low CVH-L8 group low frequency/high frequency (LF/HF) ratio was significantly correlated with PWV (r = 0.338, p = 0.047) and atherogenic index of plasma with Framingham risk score (r = 0.446, p = 0.008), even after adjustment for age and sex. CONCLUSION: In this sample of obese individuals, low CVH-L8 was associated with higher peripheral and central blood pressures, and evidence of early vascular aging with arterial stiffness and endothelial dysfunction.

Acute Effects of Dietary Nitrate on Central Pressure and Endothelial Function in Hypertensive Patients: A Randomized, Placebo-Controlled Crossover Study. / Efeitos Agudos do Nitrato Dietético na Pressão Central e Desempenho Cardíaco em Hipertensos: Estudo Cruzado, Randomizado e Placebo-Controlado.

BACKGROUND: The diet's inorganic nitrate (NO3-) may provide a physiological substrate for reducing nitrate (NO2-) to NO independent of the endothelium. Studies suggest that inorganic NO3- has beneficial effects on cardiovascular health. OBJECTIVE: This study evaluated the acute effects of 500 mL nitrate-rich beetroot juice (BRJ; containing 11.5mmol NO3-) on blood pressure and endothelial function in treated hypertensive patients. METHODS: A randomized, placebo-controlled, crossover study was conducted in treated hypertensive patients (n=37; women=62%) who underwent clinical and nutritional evaluation and assessment of central hemodynamic parameters and microvascular reactivity. The significance level was p<0.05. RESULTS: The mean age was 59±7 years, and mean systolic and diastolic blood pressures were 142±10/83±9mmHg. There was a significant increase in the subendocardial viability ratio (SEVR; 149±25 vs. 165±30%, p<0.001) and reduction in ejection duration (ED; 37±4 vs. 34±4%, p<0.001) in the beetroot phase but no significant SEVR difference in the control phase. The % increase in perfusion (155 vs. 159 %, p=0.042) was significantly increased in the beetroot phase, which was not observed in the control phase. In the beetroot phase, the change in SEVR showed a significant correlation with the change in the area under the curve of post-occlusive reactive hyperemia (AUC-PORH) (r=0.45, p=0.012). The change in ED showed a significant correlation with the post-intervention perfusion peak (r=-0.37, p=0.031) and AUC-PORH (r=-0.36, p=0.046). CONCLUSIONS: The acute ingestion of BRJ by hypertensive patients resulted in an improvement of endothelial function, which was associated with higher subendocardial viability and performance in myocardial contraction.

FUNDAMENTO: O nitrato inorgânico (NO3­) da dieta pode fornecer substrato fisiológico para reduzir o nitrito (NO2­) a óxido nítrico (NO) independente do endotélio. Estudos sugerem que o NO3­ inorgânico tem efeitos benéficos na saúde cardiovascular. OBJETIVOS: Este estudo avaliou os efeitos agudos de 500 mL de suco de beterraba rico em nitrato (SB; contendo 11,5mmol NO3­) na pressão arterial e na função endotelial em pacientes hipertensos tratados. MÉTODOS: Estudo cruzado, randomizado, controlado por placebo foi realizado em pacientes hipertensos tratados (n=37; mulheres=62%) que foram submetidos à avaliação clínica e nutricional, avaliação dos parâmetros hemodinâmicos centrais e reatividade microvascular. O nível de significância foi p<0,05. RESULTADOS: A média de idade foi 59±7 anos e das pressões sistólica e diastólica foi de 142±10/83±9 mmHg. Houve aumento significativo na taxa de viabilidade subendocárdica (RVSE; 149±25 vs. 165±30%, p<0,001) e redução na duração da ejeção (DE; 37±4 vs. 34±4%, p<0,001) na fase beterraba, mas nenhuma diferença significativa de RVSE na fase controle. O % de aumento na perfusão (155 vs. 159%, p=0,042) cresceu significativamente na fase beterraba, o que não foi observado na fase controle. Na fase beterraba, a alteração da RVSE apresentou correlação significativa com a alteração da área sob a curva de hiperemia reativa pós-oclusiva (ASC-HRPO) (r=0,45, p=0,012). A mudança na DE mostrou uma correlação significativa com pico de perfusão pós-intervenção (r=-0,37, p=0,031) e ASC-HRPO (r=-0,36, p=0,046). CONCLUSÃO: A ingestão aguda de SB por pacientes hipertensos resultou em melhora da função endotelial, que foi associada à maior viabilidade subendocárdica e desempenho na contração miocárdica.

Effects of weight loss through lifestyle changes on heart rate variability in overweight and obese patients: A systematic review.

BACKGROUND & AIMS: The effects of calorie restriction and physical activity on autonomic regulation and cardiac vagal control in overweight and obese individuals remain inconsistent. Thus, this systematic review aimed to evaluate the weight loss effects through lifestyle changes on heart rate variability (HRV) markers in overweight and obese subjects. METHODS: A systematic search for studies published up to November 2021 was conducted in MEDLINE, Embase, EBSCO host and VHL REGIONAL/LILACS. The main outcomes were changes in HRV indices from pre- and post-nutritional intervention and exercise in overweight and obese individuals. This review was registered in PROSPERO: CRD42021274467. RESULTS: The literature search retrieved 959 articles, of which 12 were included in this review. The intervention in nine studies was diet only, in two studies was diet and exercise, and in one study diet was compared to diet and exercise. The weight loss was greater than 10% in four studies and between 5 and 10% in three studies. Most of the studies revealed that weight loss through lifestyle changes seems to promote beneficial effects on HRV, restoring sympathovagal balance by increasing parasympathetic activity and reducing sympathetic activation. CONCLUSION: This systematic review exhibited the beneficial effects of weight loss through lifestyle changes on cardiac autonomic control in overweight and obese individuals. Future investigations need standardization of HRV indices for better interpretation of autonomic function in different clinical situations.

Effects of probiotics on body adiposity and cardiovascular risk markers in individuals with overweight and obesity: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND & AIMS: Evidence suggests that gut microbiota is a potential factor in the pathophysiology of both obesity and related metabolic disorders. While individual randomized controlled trials (RCTs) have evaluated the effects of probiotics on adiposity and cardiovascular disease (CVD) risk factors in subjects with overweight and obesity, the results are inconsistent. Thus, this systematic review and meta-analysis aimed to evaluate the effects of probiotic supplementation on body weight, body adiposity and CVD risk markers in overweight and obese subjects. METHODS: A systematic search for RCTs published up to December 2020 was conducted in MEDLINE (via PubMed), EMBASE, Scopus and LILACS. Meta-analysis using a random-effects model was chosen to analyze the impact of combined trials. RESULTS: Twenty-six RCTs (n = 1720) were included. Data pooling showed a significant effect of probiotics in reducing body weight (MD:-0.70 kg; 95%CI:-1.04,-0.35 kg; P < 0.0001), body mass index (BMI) (MD:-0.24 kg/m2; 95%CI:-0.35,-0.12 kg/m2; P = 0.0001), waist circumference (WC) (MD:-1.13 cm; 95%CI:-1.54,-0.73 cm; P < 0.0001), fat mass (MD:-0.71 kg; 95%CI:-1.10,-0.32 kg; P = 0.0004), tumor necrosis factor-α (MD:-0.16 pg/ml; 95%CI:-0.24,-0.08 pg/ml; P = 0.0001), insulin (MD:-0.85mcU/ml; 95%CI:-1.50,-0.21mcU/ml; P = 0.010), total cholesterol (MD:-0.16 mmol/l; 95%CI:-0.26,-0.05 mmol/l; P = 0.003) and LDL (MD:-0.09 mmol/l; 95%CI:-0.16,-0.03 mmol/l; P = 0.006) compared with control groups. There was a significant decrease in body weight, BMI and WC in studies using both single and multi-bacterial species. Decreases in body adiposity parameters were only observed in studies using a probiotic dose of ≥ 1010 CFU and for ≥8 weeks duration. CONCLUSIONS: The present meta-analysis suggests that probiotics consumption may be helpful for improving body weight, body adiposity and some CVD risk markers in individuals with overweight and obesity. The review was registered on PROSPERO (International prospective register of systematic reviews): CRD42020183136.

Effects of Oral Magnesium Supplementation on Vascular Function: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

INTRODUCTION: The effects of magnesium (Mg) supplementation on vascular function have been evaluated in some randomized controlled trials (RCT) but their results are conflicting. AIM: A systematic review and meta-analysis were conducted to summarize the effects of oral Mg supplementation on vascular function in RCT. METHODS: The databases MEDLINE (PubMed), Embase, Web of Science and Cochrane Library were accessed from inception to May 27, 2019. Intergroup differences (treatment vs. control group) related to changes in flow-mediated dilation (FMD) and pulse wave velocity (PWV), expressed as mean and standard deviation, were used to evaluate the effect of Mg supplementation on these outcomes. The results of the meta-analysis were expressed using a random-effects model. The heterogeneity between studies was evaluated using the I2 statistic. RESULTS: The oral supplementation of Mg had no significant effect on FMD (mean difference 2.13; 95% CI - 0.56, 4.82; p = 0.12) and PWV (mean difference - 0.54, 95% CI - 1.45, 0.36, p = 0.24). Heterogeneity for both outcomes (FMD and PWV) was high (I2 = 99%, p < 0.001). However, in subgroup analyses, oral Mg significantly improved FMD in studies longer than 6 months, in unhealthy subjects, in individuals older than 50 years, or in those with body mass index (BMI) ≥ 25 kg/m2. The reduced number of RCT and the heterogeneity among them were the main limitations. CONCLUSIONS: This meta-analysis suggest that oral Mg supplementation may improve endothelial function when conducted at least for 6 months and in unhealthy, overweight or older individuals. Registration number: PROSPERO CRD42019111462.

Microvascular Reactivity in Hypertensive Patients with High Body Adiposity. / Estudo da Reatividade Microvascular em Pacientes Hipertensos com Adiposidade Corporal Elevada.

BACKGROUND: Several anthropometric indexes have been proposed to determine the association between overweight and cardiovascular risk factors. OBJECTIVE: To evaluate the relationship between body adiposity and microvascular reactivity in hypertensive patients under antihypertensive therapy. METHODS: Treated hypertensive patients aged 40 to 70 were submitted to evaluation of anthropometric indexes: conicity (CI), body adiposity (BAI), visceral adiposity (VAI) and waist-to-height ratio (WHtR). Participants were divided by the terciles of fat percentage (%F) obtained by bioelectrical impedance. The patients underwent microvascular reactivity test (Laser Speckle Contrast Image) and pulse wave velocity (PWV) measurement. The p value <0.05 was considered statistically significant. RESULTS: The variation of the area under the curve (AUC) of the skin perfusion was lower in the upper tercile (97±57% vs. 67±36%; p=0.027). %F showed significant correlation with WHtR (r=0.77; p<0.001), VAI (r=0.41; p=0.018), CI (r=0.60; p<0.001), BAI (r=0.65; p<0.001) in men and only with WHtR (r=0.55; p<0.001) and BAI (r=0.60; p<0.001) in women. In linear regression, AUC was independently associated with %F (ß=-3.15; p=0.04) in women and with blood glucose (ß=-1.15; p=0.02) in men. There was no difference in PWV measurements. CONCLUSION: Anthropometric indices were more associated with %F in men. Higher body adiposity was associated with lower microvascular reactivity, which was more evident in women. There was no difference in arterial stiffness, which may have been influenced by antihypertensive treatment.

FUNDAMENTO: Diversos índices antropométricos têm sido propostos para determinar a associação entre excesso de peso e fatores de risco cardiovascular. OBJETIVO: Avaliar a relação entre adiposidade corporal e reatividade microvascular em pacientes hipertensos sob terapia anti-hipertensiva. MÉTODOS: Pacientes hipertensos tratados de 40 a 70 anos foram submetidos à avaliação de índices antropométricos: conicidade (IC), adiposidade corporal (IAC), adiposidade visceral (IAV) e relação cintura-estatura (RCE). Os participantes foram divididos pelos tercis de percentual de gordura (%G) obtido pela bioimpedância elétrica (BIA) e submetidos a teste de reatividade microvascular (laser speckle contrast image), medida da velocidade da onda de pulso (VOP). O valor de p < 0,05 foi considerado estatisticamente significativo. RESULTADOS: A variação da área sob a curva (ASC) da perfusão cutânea foi inferior no tercil superior (97 ± 57% vs. 67 ± 36%; p = 0,027). O %G apresentou correlação significativa com RCE (r = 0,77; p < 0,001), IAV (r = 0,41; p = 0,018), IC (r = 0,60; p < 0,001) e IAC (r = 0,65; p < 0,001) nos homens e somente com RCE (r = 0,55; p < 0,001) e IAC (r = 0,60; p < 0,001) nas mulheres. Na regressão linear, a ASC mostrou associação independente com o %G (ß =­3,15; p = 0,04) nas mulheres e com a glicemia (ß = ­1,15; p = 0,02) nos homens. Não houve diferença nas medidas de VOP. CONCLUSÃO: Os índices antropométricos de obesidade foram mais associados ao %G nos homens. A maior adiposidade corporal foi relacionada com menor reatividade microvascular, o que foi mais evidente nas mulheres. Não houve diferença na rigidez arterial, o que pode ter sido influenciado pelo tratamento anti-hipertensivo.

Efeitos da Suplementação de Vitamina D sobre Parâmetros Hemodinâmicos Centrais e Sistema Nervoso Autônomo em Indivíduos com Obesidade ou Sobrepeso / Effects of Vitamin D Supplementation on Central Hemodynamic Parameters and Autonomic Nervous System in Obese or Overweight Individuals

Resumo Fundamento Estudos prévios têm sido inconsistentes em demonstrar efeitos cardiovasculares benéficos da suplementação de vitamina D. Objetivo Avaliar efeitos da suplementação de vitamina D3 sobre parâmetros hemodinâmicos centrais e atividade autonômica em indivíduos obesos/sobrepeso e baixos níveis de vitamina D (<30ng/dl). Métodos Ensaio clínico prospectivo, randomizado, duplo-cego (NCT 05689632), adultos 40-65 anos com índice de massa corporal ≥25<40 kg/m2. Hemodinâmica central avaliada por método oscilométrico (Mobil-O-Graph®), variabilidade da frequência cardíaca utilizando frequencímetro Polar (software Kubios®). Os pacientes (n=53) receberam placebo no grupo controle (CO, n=25) ou vitamina D3 (VD, n=28) 7000 UI/dia, avaliados antes (S0) e após 8 semanas (S8) com nível de significância de 0,05. Resultados Os grupos foram homogêneos na idade (51±6 vs. 52±6 anos, p=0,509) e níveis de vitamina D (22,8±4,9 vs. 21,7±4,5ng/ml, p=0,590). Na S8, o grupo VD apresentou níveis significativamente maiores de vitamina D (22,5 vs. 35,6ng/ml, p<0,001). Apenas o grupo VD mostrou redução significativa da pressão arterial sistólica (PAS; 123±15 vs. 119±14mmHg, p=0,019) e fosfatase alcalina (213±55 vs. 202±55mg/dl, p=0,012). O grupo CO mostrou elevação da pressão de aumento (AP: 9 vs. 12mmHg, p=0,028) e do índice de incremento (Aix: 26 vs. 35%, p=0,020), o que não foi observado no grupo VD (AP: 8 vs. 8mmHg, Aix: 26 vs. 25%, p>0,05). Grupo VD apresentou aumento no índice do sistema nervoso (iSN) parassimpático (-0,64±0,94 vs. -0,16±1,10, p=0,028) e no intervalo R-R (866±138 vs. 924±161ms, p=0,026). Conclusão Nesta amostra, a suplementação diária de vitamina D durante oito semanas resultou em melhora dos níveis pressóricos, parâmetros hemodinâmicos centrais e do equilíbrio autonômico.

Abstract Background Previous studies have been inconsistent in demonstrating beneficial cardiovascular effects of vitamin D supplementation. Objective To evaluate the effects of vitamin D3 supplementation on central hemodynamic parameters and autonomic activity in obese/overweight individuals with low vitamin D levels (<30ng/dl). Methods Adults 40-65 years old with body mass index ≥25<40 kg/m2 were enrolled in this prospective, randomized, double-blind clinical trial (NCT 05689632). Central hemodynamics was assessed using the oscillometric method (Mobil-O-Graph®), and heart rate variability using a Polar heart rate monitor (Kubios® software). Patients (n=53) received a placebo in the control group (CO, n=25) or vitamin D3 (VD, n=28) 7000 IU/day, and were evaluated before (W0) and after 8 weeks (W8) with a significance level of 0.05. Results The groups were homogeneous regarding age (51±6 vs 52±6 years, p=0.509) and vitamin D levels (22.8±4.9 vs 21.7±4.5ng/ml, p=0.590). At W8, the VD group had significantly higher levels of vitamin D (22.5 vs 35.6ng/ml, p<0.001). Only the VD group showed a significant reduction in systolic blood pressure (SBP; 123±15 vs 119±14mmHg, p=0.019) and alkaline phosphatase (213±55 vs 202±55mg/dl, p=0.012). The CO group showed an increase in augmentation pressure (AP: 9 vs 12 mmHg, p=0.028) and augmentation index (AIx: 26 vs 35%, p=0.020), which was not observed in the VD group (AP: 8 vs 8 mmHg, AIx: 26 vs 25%, p>0.05). VD group showed an increase in the parasympathetic nervous system index (PNSi) (-0.64±0.94 vs -0.16±1.10, p=0.028) and the R-R interval (866±138 vs 924±161 ms, p= 0.026). Conclusion In this sample, eight weeks of daily vitamin D supplementation resulted in an improvement in blood pressure levels and autonomic balance.

Association of urinary sodium/potassium ratio with structural and functional vascular changes in non-diabetic hypertensive patients.

Studies aiming to associate the sodium/potassium (Na/K) ratio with hypertension use 24-hour urinary excretion as a daily marker of ingestion. The objective of this study was to evaluate the association between urinary Na/K ratio and structural and functional vascular alterations in non-diabetic hypertensive patients. In hypertensive patients (n = 72), aged between 40 and 70 years, both sexes (61% women), in use of hydrochlorothiazide, we measured blood pressure, 24-hour urine sample collection, assessment of carotid-femoral pulse wave velocity (cf-PWV, Complior), central hemodynamic parameters (SphygmoCor), and post-occlusive reactive hyperemia (PORH). The participants were divided according to the tertile of 24-hour urinary Na/K ratio. Each group contained 24 patients. Systolic blood pressure was higher in T2 (133 ± 9 vs 140 ± 9 mmHg, P = .029). C-reactive protein (CRP) presented higher values in T3 as compared to T1 [0.20(0.10-0.34) vs 1.19 (0.96-1.42) mg/dL, P < .001]. Higher values in T3 were also observed for aortic systolic pressure (aoSP) [119(114-130) vs 135(125-147) mmHg, P = .002] and cf-PWV (9.2 ± 1.6 vs 11.1 ± 1.5 m/s, P < .001). The urinary Na/K ratio presented significant correlations with proteinuria (r = .27, P = .023), CRP (r = .77, P < .001), cf-PWV (r = .41, P < .001), and post-occlusive reactive hyperemia on cutaneous vascular conductance (PORH CVC) (r = -.23, P = .047). By multivariate linear regression, it was detected an independent and significant association of cf-PWV with urinary Na/K ratio (R2  = 0.17, P < .001) and PORH CVC with CRP (R2  = 0.30, P = .010). Our data indicated that increased urinary Na/K ratio in non-diabetic hypertensive patients was associated with higher degree of inflammation, raised peripheral and central pressure levels, and changes suggestive of endothelial dysfunction and arterial stiffness.

Efeitos Agudos do Nitrato Dietético na Pressão Central e Desempenho Cardíaco em Hipertensos: Estudo Cruzado, Randomizado e Placebo-Controlado / Acute Effects of Dietary Nitrate on Central Pressure and Endothelial Function in Hypertensive Patients: A Randomized, Placebo-Controlled Crossover Study

Resumo Fundamento O nitrato inorgânico (NO3-) da dieta pode fornecer substrato fisiológico para reduzir o nitrito (NO2-) a óxido nítrico (NO) independente do endotélio. Estudos sugerem que o NO3- inorgânico tem efeitos benéficos na saúde cardiovascular. Objetivos Este estudo avaliou os efeitos agudos de 500 mL de suco de beterraba rico em nitrato (SB; contendo 11,5mmol NO3-) na pressão arterial e na função endotelial em pacientes hipertensos tratados. Métodos Estudo cruzado, randomizado, controlado por placebo foi realizado em pacientes hipertensos tratados (n=37; mulheres=62%) que foram submetidos à avaliação clínica e nutricional, avaliação dos parâmetros hemodinâmicos centrais e reatividade microvascular. O nível de significância foi p<0,05. Resultados A média de idade foi 59±7 anos e das pressões sistólica e diastólica foi de 142±10/83±9 mmHg. Houve aumento significativo na taxa de viabilidade subendocárdica (RVSE; 149±25 vs. 165±30%, p<0,001) e redução na duração da ejeção (DE; 37±4 vs. 34±4%, p<0,001) na fase beterraba, mas nenhuma diferença significativa de RVSE na fase controle. O % de aumento na perfusão (155 vs. 159%, p=0,042) cresceu significativamente na fase beterraba, o que não foi observado na fase controle. Na fase beterraba, a alteração da RVSE apresentou correlação significativa com a alteração da área sob a curva de hiperemia reativa pós-oclusiva (ASC-HRPO) (r=0,45, p=0,012). A mudança na DE mostrou uma correlação significativa com pico de perfusão pós-intervenção (r=-0,37, p=0,031) e ASC-HRPO (r=-0,36, p=0,046). Conclusão A ingestão aguda de SB por pacientes hipertensos resultou em melhora da função endotelial, que foi associada à maior viabilidade subendocárdica e desempenho na contração miocárdica.

Abstract Background The diet's inorganic nitrate (NO3-) may provide a physiological substrate for reducing nitrate (NO2-) to NO independent of the endothelium. Studies suggest that inorganic NO3- has beneficial effects on cardiovascular health. Objective This study evaluated the acute effects of 500 mL nitrate-rich beetroot juice (BRJ; containing 11.5mmol NO3-) on blood pressure and endothelial function in treated hypertensive patients. Methods A randomized, placebo-controlled, crossover study was conducted in treated hypertensive patients (n=37; women=62%) who underwent clinical and nutritional evaluation and assessment of central hemodynamic parameters and microvascular reactivity. The significance level was p<0.05. Results The mean age was 59±7 years, and mean systolic and diastolic blood pressures were 142±10/83±9mmHg. There was a significant increase in the subendocardial viability ratio (SEVR; 149±25 vs. 165±30%, p<0.001) and reduction in ejection duration (ED; 37±4 vs. 34±4%, p<0.001) in the beetroot phase but no significant SEVR difference in the control phase. The % increase in perfusion (155 vs. 159 %, p=0.042) was significantly increased in the beetroot phase, which was not observed in the control phase. In the beetroot phase, the change in SEVR showed a significant correlation with the change in the area under the curve of post-occlusive reactive hyperemia (AUC-PORH) (r=0.45, p=0.012). The change in ED showed a significant correlation with the post-intervention perfusion peak (r=-0.37, p=0.031) and AUC-PORH (r=-0.36, p=0.046). Conclusions The acute ingestion of BRJ by hypertensive patients resulted in an improvement of endothelial function, which was associated with higher subendocardial viability and performance in myocardial contraction.

Estudo da Reatividade Microvascular em Pacientes Hipertensos com Adiposidade Corporal Elevada / Microvascular Reactivity in Hypertensive Patients with High Body Adiposity

Resumo Fundamento: Diversos índices antropométricos têm sido propostos para determinar a associação entre excesso de peso e fatores de risco cardiovascular. Objetivo: Avaliar a relação entre adiposidade corporal e reatividade microvascular em pacientes hipertensos sob terapia anti-hipertensiva. Métodos: Pacientes hipertensos tratados de 40 a 70 anos foram submetidos à avaliação de índices antropométricos: conicidade (IC), adiposidade corporal (IAC), adiposidade visceral (IAV) e relação cintura-estatura (RCE). Os participantes foram divididos pelos tercis de percentual de gordura (%G) obtido pela bioimpedância elétrica (BIA) e submetidos a teste de reatividade microvascular (laser speckle contrast image), medida da velocidade da onda de pulso (VOP). O valor de p < 0,05 foi considerado estatisticamente significativo. Resultados: A variação da área sob a curva (ASC) da perfusão cutânea foi inferior no tercil superior (97 ± 57% vs. 67 ± 36%; p = 0,027). O %G apresentou correlação significativa com RCE (r = 0,77; p < 0,001), IAV (r = 0,41; p = 0,018), IC (r = 0,60; p < 0,001) e IAC (r = 0,65; p < 0,001) nos homens e somente com RCE (r = 0,55; p < 0,001) e IAC (r = 0,60; p < 0,001) nas mulheres. Na regressão linear, a ASC mostrou associação independente com o %G (β =-3,15; p = 0,04) nas mulheres e com a glicemia (β = -1,15; p = 0,02) nos homens. Não houve diferença nas medidas de VOP. Conclusão: Os índices antropométricos de obesidade foram mais associados ao %G nos homens. A maior adiposidade corporal foi relacionada com menor reatividade microvascular, o que foi mais evidente nas mulheres. Não houve diferença na rigidez arterial, o que pode ter sido influenciado pelo tratamento anti-hipertensivo.

Abstract Background: Several anthropometric indexes have been proposed to determine the association between overweight and cardiovascular risk factors. Objective: To evaluate the relationship between body adiposity and microvascular reactivity in hypertensive patients under antihypertensive therapy. Methods: Treated hypertensive patients aged 40 to 70 were submitted to evaluation of anthropometric indexes: conicity (CI), body adiposity (BAI), visceral adiposity (VAI) and waist-to-height ratio (WHtR). Participants were divided by the terciles of fat percentage (%F) obtained by bioelectrical impedance. The patients underwent microvascular reactivity test (Laser Speckle Contrast Image) and pulse wave velocity (PWV) measurement. The p value <0.05 was considered statistically significant. Results: The variation of the area under the curve (AUC) of the skin perfusion was lower in the upper tercile (97±57% vs. 67±36%; p=0.027). %F showed significant correlation with WHtR (r=0.77; p<0.001), VAI (r=0.41; p=0.018), CI (r=0.60; p<0.001), BAI (r=0.65; p<0.001) in men and only with WHtR (r=0.55; p<0.001) and BAI (r=0.60; p<0.001) in women. In linear regression, AUC was independently associated with %F (β=−3.15; p=0.04) in women and with blood glucose (β=−1.15; p=0.02) in men. There was no difference in PWV measurements. Conclusion: Anthropometric indices were more associated with %F in men. Higher body adiposity was associated with lower microvascular reactivity, which was more evident in women. There was no difference in arterial stiffness, which may have been influenced by antihypertensive treatment.