Effect of whole soy and purified daidzein on ambulatory blood pressure and endothelial function--a 6-month double-blind, randomized controlled trial among Chinese postmenopausal women with prehypertension

BACKGROUND/OBJECTIVES

Although observational studies suggest that soy foods or isoflavones are cardio-protective, clinical trials on whole soy or isoflavone daidzein (one major isoflavone and the precursor of equol) on blood pressure (BP) and endothelial function (EF) are few and have not been specifically conducted among equol producers, a population most likely to benefit from soy treatment.

SUBJECTS/METHODS

We performed a 6-month double-blind, randomized, placebo-controlled trial to examine the effect of whole soy (soy flour) or purified daidzein on BP and EF in prehypertensive or untreated hypertensive postmenopausal women verified to be equol producers. A total of 270 eligible women were recruited and randomized to either one of the three treatment groups, 40 g soy flour (whole soy group), 40 g low-fat milk powder+63 mg daidzein (daidzein group) or 40 g low-fat milk powder (active control group) daily, each given as a solid beverage powder for 6 months. The primary outcome measures were 24 h ambulatory BP (ABP) and EF assessed by flow-mediated dilation using brachial artery ultrasound.

RESULTS

A total of 253 subjects completed the study according to protocol. Urinary isoflavones indicated good compliance with the interventions. Intention to treat and per-protocol analysis indicated that there was no significant difference in the 6-month changes or % changes in parameters of ABP and brachial flow-mediated dilation among the three treatment groups. A further subgroup analysis among hypertensive women (n=138) did not alter the conclusions.

CONCLUSIONS

Whole soy and purified daidzein had no significant effect on BP and vascular function among equol-producing postmenopausal women with prehypertension or untreated hypertension.

Chinese Herbal Medicine Combined with Conventional Therapy for Blood Pressure Variability in Hypertension Patients: A Systematic Review of Randomized Controlled Trials

Objective. The aim of this systematic review is to evaluate effect of Chinese medicine combined with conventional therapy on blood pressure variability (BPV) in hypertension patients. Methods. All randomized clinical trials (RCTs) comparing Chinese medicine with no intervention or placebo on the basis of conventional therapy were included. Data extraction, analyses, and quality assessment were performed according to the Cochrane standards. Results. We included 13 RCTs and assessed risk of bias for all the trials. Chinese medicine has a significant effect in lowering blood pressure (BP), reducing BPV in the form of standard deviation (SD) or coefficient of variability (CV), improving nighttime BP decreased rate, and reversing abnormal rhythm of BP. Conclusions. Chinese medicine was safe and showed beneficial effects on BPV in hypertension patients. However, more rigorous trials with high quality are warranted to give high level of evidence before recommending Chinese medicine as an alternative or complementary medicine to improve BPV in hypertension patients.

The prognostic value of long-term visit-to-visit blood pressure variability on stroke in real-world practice: a dynamic cohort study in a large representative sample of Chinese hypertensive population

BACKGROUND

The prognostic significance of long-term visit-to-visit blood pressure variability (BPV) has not yet been validated in "real world" hypertensive patients. The aim of the current study is to explore the prognostic value of BPV on stroke in hypertensive patients.

METHODS

This was a dynamic prospective cohort study based on electronic medical records in Shanghai, China. Hypertensive patients (N=122,636) without history of stroke at baseline, were followed up from 2005 to 2011. The cohort comprised of 4522 stroke patients and 118,114 non-stroke patients during a mean follow-up duration of 48 months. BPV was measured by standard deviation (SD) and the coefficient of variation (CV) of blood pressure.

RESULTS

The visit-to-visit variability of both systolic blood pressure (SBP) and diastolic blood pressure (DBP) was independently associated with the occurrence of stroke [SD: the hazard ratios (95% confidence intervals) of SBP and DBP were 1.042 (1.021 to 1.064) and 1.052 (1.040 to 1.065); CV: the hazard ratios (95% confidence intervals) of SBP and DBP were 1.183 (1.010 to 1.356) and 1.151 (1.005 to 1.317), respectively]. The hazard ratio values increased along with an increase of the BPV levels of SBP and DBP. The increment effect remained significant after controlling the blood pressure control status of subjects.

CONCLUSIONS

Increased BPV of both SBP and DBP, independent of the average blood pressure, is a predictor of stroke among community hypertensive patients in real-world clinical practice. The risk of stroke increased along with increased BPV. Stabilizing BPV might be a therapeutic target in hypertension.

Heart rate and blood pressure variability in children with chronic kidney disease: a report from the CKiD study

BACKGROUND

Autonomic nervous system dysfunction and sympathetic nervous system over-activity play important roles in the development of hypertension associated with chronic kidney disease (CKD). In adults, increased blood pressure variability (BPV) appears to be directly related to sympathetic over-activity with increased risk of end-organ damage and cardiovascular events. Decreased heart rate variability (HRV) has been observed in adults with CKD, and is an independent predictor of mortality.

METHODS

The purpose of this study was to evaluate BPV and HRV in pediatric patients enrolled in the Chronic Kidney Disease in Children Study. Ambulatory blood pressure monitoring data were available for analysis of 215 person-visits from 144 children that were not receiving antihypertensive medications.

RESULTS

BPV and HRV were determined by standard deviation and coefficient of variation for heart rate and systolic and diastolic blood pressure for each patient averaged for wake/sleep periods during 24-h monitoring. Uniformly lower values were displayed during sleep versus wake periods: BPV was 20 % lower during sleep (p < 0.001) and HRV was 30 % lower during sleep (p < 0.001). A significant increase in systolic BPV was observed in hypertensive children compared to children with normal blood pressure (6.9 %, p = 0.009). Increased diastolic BPV was detected among hypertensive children during sleep period compared to children with normal blood pressure (11.5 %, p = 0.008). There was a significant decrease in HRV in hypertensive compared to normotensive children (-8.2 %, p = 0.006).

CONCLUSIONS

These findings are similar to those in adult patients and may underscore childhood origin and natural progression of adverse cardiovascular outcomes in adults with CKD.