Late Systolic Blood Pressure Research Articles

Obesity Weight Loss Phenotypes in CKD: Findings From the Chronic Renal Insufficiency Cohort Study

Although people with chronic kidney disease (CKD) and obesity have important motivations to lose weight, weight loss is also associated with health risks. We examined whether patterns of change in systolic blood pressure (SBP), serum albumin level, and fat-free mass (FFM) can help to differentiate between healthy and high-risk weight loss in this population. Using data from the Chronic Renal Insufficiency Cohort Study (CRIC), we estimated a joint multivariate latent class model with 6 classes to identify distinct trajectories of body mass index (BMI), albumin, and SBP among participants with obesity (BMI≥30 kg/m2 at baseline), accounting for informative missingness from death. In a secondary analysis, we fit a 6-class model with BMI and FFM. Among 2831 participants (median baseline BMI 35.6, interquartile range [IQR] 32.4-40.0 kg/m2), median follow-up was 6.8 (IQR 4.8-12.9) years, median age was 61 (IQR 54-67) years, 53% were male, 50% were non-Hispanic Black, and 82% were trying to control or lose weight at baseline. Latent classes were associated with mortality risk (5-year cumulative incidence of mortality 6.8% and 1.5% in class 6 and 3, respectively). Class 6 had the highest mortality rate and was characterized by early, steep BMI loss, early serum albumin decline, and late SBP increase. In the secondary analysis, a class characterized by steep BMI and FFM loss was associated with the highest death risk. Among adults with CKD and obesity, BMI loss with concomitant serum albumin or FFM loss was associated with a high risk of death.

Effect of transcutaneous electrical nerve stimulation on peripheral to central blood pressure ratio in healthy subjects.

To investigate the effect of transcutaneous electrical nerve stimulation (TENS) on the arterial stiffness in healthy young adult and middle-aged men using the augmentation index (AI-x) and hemodynamic measures. Twenty-four men (12 aged 27·25±5·53years and 12 aged 54·83±5·10years) were randomly allocated to two subgroups: TENS or placebo in ganglion region for 45min. The AI-x and hemodynamic measures [late systolic blood pressure (SBP), central blood pressure (CBP), difference between P1 and P2 (ΔP) and tension time index (TTI)] were determined before and after protocols. TENS resulted in reduction of SBP in younger adults (TENSpre: 111±2; post: 105±2·2mm Hg; PLACEBOpre: 113±1·8; post: 114±2·5mm Hg; GEE, P<0·01), whereas no difference was found in middle-aged group. TENS also resulted in reduction of AI-x younger adults group (TENSpre: 56±2·8; post: 53±2%; PLACEBOpre: 55±3; post: 58±2·5%; GEE, P<0·01). ΔP and TTI were significantly decreased after the application of TENS in both groups, but significantly greater reductions in TTI and the SBP/CBP ratio were found in the group of younger adults. The acute application of ganglion TENS attenuated arterial stiffness in younger adults as well as hemodynamic measures in the middle-aged group. This method could emerge as effective therapy for the management of arterial blood pressure.

A Model of Systolic Blood Pressure During the Course of Dialysis and Clinical Factors Associated With Various Blood Pressure Behaviors

Little is known about the behavior of systolic blood pressure (SBP) during hemodialysis. Prospective observational cohort. 218 prevalent hemodialysis patients treated at 5 participating DaVita Dialysis units. Clinical variables that may plausibly influence the behavior of SBP during the course of hemodialysis sessions. SBP at the onset of dialysis and its rate of change (slope) over the first 25% and latter 75% of the treatment interval. SBPs measured and recorded per clinical protocol during the first 30 days of study (median, 11 treatments/patient; SBP measured at 30-minute intervals). Intradialytic SBP behavior is well characterized by a 2-slope linear spline model, which describes SBP at time zero, a rapid decrease during the first 25% of the treatment (early), and a more gradual decrease thereafter (late). Higher ultrafiltration volume and rate each are associated with greater SBP at the start of dialysis and more rapid early and late SBP decreases. Use of a higher number of antihypertensives was associated with greater time zero SBP. Calcium acetate use is associated with high SBP at the start of hemodialysis and a more pronounced decrease during the early and late parts of treatment. Over-representation of blacks and patients with congestive heart failure; observational design; use of clinically measured blood pressures. Intradialytic SBP can be characterized using 3 parameters: value at the start of dialysis and slopes during the first 25% and latter 75% of treatment. Practices related to fluid management, antihypertensive use, and metabolic bone disease control are associated with blood pressure behavior during dialysis. Further work is needed to confirm findings and measure associations between various aspects of intradialytic blood pressure behavior and clinical outcomes.

Vasoactive drugs for acute stroke.

It is unclear whether blood pressure (BP) should be altered actively during the acute phase of stroke. To assess the effect of lowering or elevating BP in people with acute stroke, and the effect of different vasoactive drugs on BP in acute stroke. We searched the Cochrane Stroke Group Trials Register (last searched June 2009), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2009), MEDLINE (1966 to October 2009), EMBASE (1980 to October 2009), and Science Citation Index (1981 to October 2009). Randomised trials of interventions that would be expected, on pharmacological grounds, to alter BP in patients within one week of the onset of acute stroke. Two review authors independently applied the trial inclusion criteria, assessed trial quality, and extracted data. We identified 131 trials involving in excess of 18,000 patients; a further 13 trials are ongoing. We obtained data for 43 trials (7649 patients). Among BP-lowering trials, beta receptor antagonists lowered BP (early systolic BP (SBP) mean difference (MD) -6.1 mmHg, 95% CI -11.4 to -0.9; late SBP MD -4.9 mmHg, 95% CI -10.2 to 0.4; late diastolic BP (DBP) MD -4.5 mmHg, 95% CI -7.8 to -1.2). Oral calcium channel blockers (CCB) lowered BP (late SBP MD -3.2 mmHg, 95% CI -5.4 to -1.1; early DBP MD -2.5, 95% CI -5.6 to 0.7; late DBP MD -2.1, 95% CI -3.5 to -0.7). Nitric oxide donors lowered BP (early SBP MD -10.3 mmHg, 95% CI -17.6 to -3.0). Prostacyclin lowered BP (late SBP MD, -7.7 mmHg, 95% CI -15.6 to 0.2; late DBP MD -3.9 mmHg, 95% CI -8.1 to 0.4). Among BP-increasing trials, diaspirin cross-linked haemoglobin (DCLHb) increased BP (early SBP MD 15.3 mmHg, 95% CI 4.0 to 26.6; late SBP MD 15.9 mmHg, 95% CI 1.8 to 30.0). None of the drug classes significantly altered outcome apart from DCLHb which increased combined death or dependency (odds ratio (OR) 5.41, 95% CI 1.87 to 15.64). There is not enough evidence to evaluate reliably the effect of altering BP on outcome after acute stroke. However, treatment with DCLHb was associated with poor clinical outcomes. Beta receptor antagonists, CCBs, nitric oxide, and prostacyclin each lowered BP during the acute phase of stroke. In contrast, DCLHb increased BP.

Dysfunctional central hemodynamic regulation after daily meal intake in metabolic syndrome

ObjectivePostprandial hyperlipidemia and insulin resistance play roles in the development of atherosclerosis in metabolic syndrome (MetS); however, the clinical significance of postprandial hemodynamic variables in this condition is still in question. The aim of this study was to investigate hemodynamic and metabolic indicators related to MetS after a mixed meal (Calorie mate, 500kcal). MethodsOf 107 participants undergoing this investigation, 24 fulfilled ATPIII criteria for MetS. The remaining 83 subjects were controls. Both the augmentation index (AI) and late systolic blood pressure in the radial artery (rSBP2) as an index of central blood pressure were monitored using HEM-9000AI (Omron Healthcare, Kyoto, Japan) until 240min after meal intake. ResultsBoth AI and rSBP2 showed significant decreases after meal intake in both groups. Changes in postprandial AI showed a similar trend in the groups. rSBP2 reduction 60min after meal ingestion was also comparable, −7.5±2.3mmHg in MetS; −7.8±0.9mmHg in control; however, delta rSBP2-120, the degree of rSBP2 reduction 120min after meal ingestion comparing the fasting level, showed a significant difference between 2 groups, −0.5±2.0mmHg in MetS; −5.3±0.9mmHg in control, P<0.02. Stepwise regression analysis revealed low-density-lipoprotein cholesterol (β=0.333, P=0.001), high-density-lipoprotein cholesterol (β=−0.209, P<0.05) and systolic blood pressure (β=−0.377, P<0.001) as independent variables for determining delta rSBP2-120. ConclusionSubjects with MetS exhibit signs of blunted rSBP2 (=central blood pressure) regulation after food intake. Dysfunctional postprandial hemodynamic regulation is another feature of MetS that may contribute to the progression of cardiovascular disease.

Effects of Obesity and Smoking on Mental Stress-Induced Blood Pressure and Augmentation Index Responses in Normotensive Young Males: The J-SHIPP Study

Exaggerated blood pressure (BP) response to mental stress has been known to be a prognostic factor for cardiovascular disease. It has been argued that such unusual vascular reactivity to mental stress may arise from insulin resistance. To examine the vascular responses to mental stress, we evaluated the stress-related changes in BP and the augmentation index (AI), an index of arterial stiffness, in normotensive young males. Changes in late systolic BP (SBP2) representing central aortic pressure were also examined. Subjects were 86 males (21+/-2 years), 13 of whom were classified as obese (>or=25 kg/m(2)). AI was obtained from the radial arterial waveform as a ratio of the height of the late systolic peak to that of the first peak. Blood pressure and AI measurements were taken before, during and after a simple mental arithmetic test (MAT) lasting 3 min. Systolic BP (baseline 125+/-13, during MAT 133+/-13, post-MAT 124+/-11 mmHg; p<0.001) and heart rate (74+/-12, 81+/-13, 74+/-11 beats/min; p<0.001) were significantly increased during the MAT, whereas AI showed a slight reduction. In a separate analysis, the opposite response was observed between obese subjects showing increased AI (54+/-11, 56+/-13, 52+/-11%) and non-obese subjects who showed reduced AI (54+/-12, 51+/-12, 53+/-12%; p=0.032). The responses in SBP and SBP2 (obese 103+/-14, 117+/-12, 104+/-12; non-obese 98+/-13, 104+/-12, 97+/-12 mmHg; p=0.007) were also larger in the obese subjects. Stress-related transient increases in arterial stiffness may be involved in the exaggerated responses in aortic pressure in obese subjects.

Relationship between Radial and Central Arterial Pulse Wave and Evaluation of Central Aortic Pressure Using the Radial Arterial Pulse Wave

Since a decrease of central aortic pressure contributes to the prevention of cardiovascular events, simple measurement of not only brachial blood pressure but also central aortic pressure may be useful in the prevention and treatment of cardiovascular diseases. In this study, we simultaneously measured radial artery pulse waves non-invasively and ascending aortic pressure invasively, before and after the administration of nicorandil. We then compared changes in central aortic pressure and radial arterial blood pressure calibrated with brachial blood pressure in addition to calculating the augmentation index (AI) at the aorta and radial artery. After nicorandil administration, the reduction in maximal systolic blood pressure in the aorta (Deltaa-SBP) was -14+/-15 mmHg, significantly larger than that in early systolic pressure in the radial artery (Deltar-SBP) (-9+/-12 mmHg). The reduction in late systolic blood pressure in the radial artery (Deltar-SBP2) was -15+/-14 mmHg, significantly larger than Deltar-SBP, but not significantly different from Deltaa-SBP. There were significant relationships between Deltaa-SBP and Deltar-SBP (r=0.81, p<0.001), and between Deltaa-SBP and Deltar-SBP2 (r=0.91, p<0.001). The slope of the correlation regression line with Deltar-SBP2 (0.83) was larger and closer to 1 than that with Deltar-SBP (0.63), showing that the relationship was close to 1:1. Significant correlations were obtained between aortic AI (a-AI) and radial AI (r-AI) (before nicorandil administration: r=0.91, p<0.001; after administration: r=0.70, p<0.001). These data suggest that the measurement of radial artery pulse wave and observation of changes in the late systolic blood pressure in the radial artery (r-SBP2) in addition to the ordinary measurement of brachial blood pressure may enable a more accurate evaluation of changes in maximal systolic blood pressure in the aorta (a-SBP).

Effect of hormone replacement therapy on non-invasive cardiovascular haemodynamics.

To determine the detailed effects of hormone replacement therapy (HRT) on non-invasive haemodynamics, including an assessment of the effect on the pulsatile afterload assessed in terms of the augmentation index and pulse-wave velocity. A cross-sectional study of healthy postmenopausal women using carotid and radial tonometry and pulse-wave velocity measurements. Community-based ambulatory women attending the menopause centre at a tertiary hospital. Seventy postmenopausal women divided into those not currently being administered HRT (n = 38, aged 46-72 years) and those who were being administered a variety of HRT (n = 32, aged 49-67 years). Central arterial pressure waveforms were measured using carotid applanation tonometry to derive the augmentation index and ejection duration. The arterial pulse-wave velocity was assessed using paired carotid, radial and dorsalis tonometry waveforms. Women being administered HRT had a significantly lower augmentation index (20.4 +/- 8.6 versus 27.0 +/- 10.2%, P = 0.005) and shorter ejection times (320 +/- 17 versus 329 +/- 18 ms, P = 0.037). There was no significant difference in brachial blood pressure (131/76 versus 129/77 mmHg). Women being administered HRT exhibited a greater reversal in the age-related loss of amplification which occurs owing to arterial stiffening. This amplification between central and peripheral systolic blood pressures was greater among women being administered HRT (5.3 +/- 6.2 versus 2.2 +/- 4.0 mmHg, P = 0.014). There was no difference in pulse-wave velocity between the two groups. HRT appears to improve the pulsatile vascular afterload by decreasing the augmentation of the late systolic blood pressure. This effect is not apparent from routine brachial cuff measurements, which, as a result, may underestimate haemodynamic benefits. Such effects may help to explain a portion of the improvement in cardiovascular morbidity found in other trials.