Minimum Blood Pressure Research Articles

Early Postresuscitation Hypotension Is Associated With Increased Mortality Following Pediatric Cardiac Arrest*

To describe the association of systolic hypotension during the first 6 hours after successful resuscitation from pediatric cardiopulmonary arrest with in-hospital mortality. Retrospective cohort study. Fifteen children's hospitals associated with the Pediatric Emergency Care Applied Research Network. Patients between 1 day and 18 years old who had a cardiopulmonary arrest, received chest compressions more than 1 minute, had a return of spontaneous circulation more than 20 minutes, and had a systolic blood pressure documented within 6 hours of arrest. None. Three hundred eighty-three patients had complete data for analysis. Patients with a documented minimum systolic blood pressure less than fifth percentile for age and sex within the first 6 hours following return of spontaneous circulation were considered to have early postresuscitation hypotension. Two hundred fourteen patients (56%) had early postresuscitation hypotension. One hundred eighty-four patients (48%) died prior to hospital discharge. After controlling for patient and cardiopulmonary arrest characteristics, hypotension in the first 6 hours following return of spontaneous circulation was associated with a significantly increased odds of in-hospital mortality (adjusted odds ratio = 1.71; 95% CI, 1.02-2.89; p = 0.042) and odds of unfavorable outcome (adjusted odds ratio = 1.83; 95% CI, 1.06-3.19; p = 0.032). In the first 6 hours following successful resuscitation from pediatric cardiac arrest, systolic hypotension was documented in 56% and was associated with a higher rate of in-hospital mortality and worse hospital discharge neurologic outcomes.

Effects of nighttime single-dose administration of vasodilating vs sympatholytic antihypertensive agents on sleep blood pressure in hypertensive patients with sleep apnea syndrome.

Obstructive sleep apneas syndrome (OSAS) is associated with nocturnal hypertension with higher sleep blood pressure (BP) and its variability, both of which increase cardiovascular risk. In this crossover design study, the effect of nighttime single-dose administration of vasodilating (nifedipine 40 mg) vs sympatholytic (carvedilol 20 mg) antihypertensive agents on sleep BP in 11 hypertensive OSAS patients was evaluated. The authors recently developed a trigger sleep BP monitor with an oxygen-triggered function that initiates BP measurement when oxygen desaturation falls. The BP-lowering effects of nifedipine on the mean (P<.05) and minimum sleep systolic BPs (SBPs) (P<.01) were stronger than those of carvedilol. Sleep SBP surge (difference between the hypoxia-peak SBP measured by oxygen-triggered function and SBPs within 30 minutes before and after the peak SBP) was only significantly reduced by carvedilol (P<.05). The nighttime dosing of both vasodilating and sympatholytic antihypertensive drugs is effective to reduce sleep BP but with different BP-lowering profiles.

Midterm Effects of Fluid Resuscitation Strategies in an Experimental Model of Lung Contusion and Hemorrhagic Shock

This study compared three different fluid resuscitation strategies in terms of respiratory tolerance and hemodynamic efficacy in a pig model of blunt chest trauma with lung contusion and controlled hemorrhagic shock. We hypothesized that the choice of fluid resuscitation strategy (type and amount of fluids) may impact differently contused lungs in terms of extravascular lung water (EVLW) 20 h after trauma. Anesthetized female pigs (n = 5/group) received five bolt shots to the right thoracic cage and allowed to hemorrhage for 30 min, with 25 to 30 mL/kg of blood loss. Pigs were randomly assigned to resuscitation groups that maintained a minimum mean arterial blood pressure of 70 mmHg with one of three methods: normal saline (NS), unrestricted normal saline; NOREPI, low-volume normal saline with norepinephrine; or HS-HES, hypertonic saline with hydroxyethyl starch. Control pigs were anesthetized, but received no injury or treatment. After 20 h, animals were killed to measure EVLW by gravimetry. Fluid loading was significantly different in each group. All three treatment groups had higher EVLW than controls. Moderate, bilateral pulmonary edema was observed in the NS and HS-HES groups. The three treatment groups showed similar reductions in oxygenation. Static pulmonary compliance was diminished in the NS and HS-HES groups, but compliance was similar in NOREPI and control groups. The NOREPI group had pathological lactate levels. This study demonstrated the impact of fluid resuscitation on contused lungs. Twenty hours after the trauma, all three resuscitation approaches showed modest clinical consequences, with moderate lung edema and reduced compliance in response to the infused volume.

Observations from the IMPROVE trial concerning the clinical care of patients with ruptured abdominal aortic aneurysm

BackgroundSingle-centre series of the management of patients with ruptured abdominal aortic aneurysm (AAA) are usually too small to identify clinical factors that could improve patient outcomes.MethodsIMPROVE is a pragmatic, multicentre randomized clinical trial in which eligible patients with a clinical diagnosis of ruptured aneurysm were allocated to a strategy of endovascular aneurysm repair (EVAR) or to open repair. The influences of time and manner of hospital presentation, fluid volume status, type of anaesthesia, type of endovascular repair and time to aneurysm repair on 30-day mortality were investigated according to a prespecified plan, for the subgroup of patients with a proven diagnosis of ruptured or symptomatic AAA. Adjustment was made for potential confounding factors.ResultsSome 558 of 613 randomized patients had a symptomatic or ruptured aneurysm: diagnostic accuracy was 91·0 per cent. Patients randomized outside routine working hours had higher operative mortality (adjusted odds ratio (OR) 1·47, 95 per cent confidence interval 1·00 to 2·17). Mortality rates after primary and secondary presentation were similar. Lowest systolic blood pressure was strongly and independently associated with 30-day mortality (51 per cent among those with pressure below 70 mmHg). Patients who received EVAR under local anaesthesia alone had greatly reduced 30-day mortality compared with those who had general anaesthesia (adjusted OR 0·27, 0·10 to 0·70).ConclusionThese findings suggest that the outcome of ruptured AAA might be improved by wider use of local anaesthesia for EVAR and that a minimum blood pressure of 70 mmHg is too low a threshold for permissive hypotension.

Factor analysis of biochemical markers associated with bone mineral density in adults.

[Purpose] The aim of this study was to find biochemical markers related to low bone mineral density in Korean adults. [Subjects and Methods] From August 1 to September 15, 2013, subjects receiving medical checkups were classified as lumbar spine bone normal, osteopenic, or osteoporotic using a bone mineral densitometer. Next, age, body mass index, and biochemical parameter differences were compared among the three groups. [Results] The results revealed that, the relevant factors were maximum blood pressure, minimum blood pressure, bone mineral density, total bilirubin, alkaline phosphatase (ALP), fasting blood glucose, iron, neutrophils, monocytes, and eosinophils. The bone mineral density of patients with osteoporosis was 0.763 times lower than that of normal subjects. The total bilirubin level of patients with osteoporosis was 0.45 times lower than that of normal subjects. The alkaline phosphatase level of patients with osteopenia was 1.059 times higher than that of normal subjects, and that in patients with osteoporosis was 1.088 times higher than that in normal subjects. The fasting blood glucose level of patients with osteoporosis was 0.963 times lower than that of normal subjects. The iron level of patients with osteoporosis was 0.986 times lower than that of normal subjects. [Conclusion] In conclusion, osteoporosis is a representative disease in elderly women due to aging and menopause, and more active interest should be taken for prevention and treatment.

Blood pressure variability in risk stratification: What does it add?

1. In this minireview we address the predictive value of blood pressure variability, over and beyond level of pressure, in randomly selected population samples. All reviewed studies had sufficient power, long follow-up duration and a wide age range. 2. We assessed blood pressure variability derived from home visit, self-measured home pressure and 24 h ambulatory monitoring. The conclusions are based mainly on novel indices of blood pressure variability: variability independent of the mean, difference between maximum and minimum blood pressure and average real variability. 3. None of these variability indices or morning surge in blood pressure substantially refined risk profiling over and beyond the blood pressure level. 4. In risk stratification, clinicians should concentrate on blood pressure level, the predominant risk factor modifiable by lifestyle measures and antihypertensive drug treatment.

The semiology of tilt-induced reflex syncope in relation to electroencephalographic changes

Syncope is defined as transient loss of consciousness as a result of cerebral hypoperfusion. Electroencephalography during syncope shows either a 'slow-flat-slow' or a 'slow' pattern. The first is believed to denote more severe hypoperfusion. Although the diagnosis of vasovagal syncope relies primarily on history taking, there is limited evidence regarding the relative importance of various clinical features, and none that relate them to the severity of electroencephalographic changes. The aim of this investigation was to study symptoms, signs and electroencephalographic changes with a 1 s resolution using electroencephalography and video data in 69 cases of tilt-induced vasovagal syncope. The main finding was that flattening of the electroencephalograph indicated more profound circulatory changes: the 'slow-flat-slow' group had a lower minimum blood pressure, longer maximum RR-interval, contained more cases with asystole and had a longer duration of loss of consciousness than the 'slow' group. Second, we describe a range of signs, including some that have rarely been reported in syncope, e.g. oral automatisms. Third, signs occurred at different rates depending on electroencephalographic flattening, suggesting a classification of syncopal signs. Type A signs (e.g. loss of consciousness, eye opening and general stiffening) develop during the first slow phase, stay present during flattening and stop in the second slow phase. Type B (particularly myoclonic jerks) occur when the electroencephalograph is slow but not flat: their abolition with electroencephalographic flattening suggests dependence on cortical activity. Type C signs (making sounds, roving eye movements and stertorous breathing) occur only in the flat phase, whereas type D (dropping the jaw and snoring) may occur either in slow or flat phases. In conclusion, our findings provide a detailed assessment of clinical symptoms in relation to electroencephalographic (EEG) changes during tilt-induced syncope.

The Short-Term Prognosis of Cardiogenic Shock Can Be Determined Using Hemodynamic Variables

Few reports address the relationship between hemodynamic variables and the cardiogenic shock outcome in critically ill patients. The present study aimed to investigate the association between hemodynamic variables and early cardiogenic shock mortality in critically ill patients. Retrospective, single-center cohort study. Tertiary academic hospital's 36-bed multidisciplinary intensive care. Initial presentation with cardiogenic shock. The authors retrospectively analyzed medical information and the hemodynamic variables (recorded during the first 24 hr following admission to the ICU) of patients with cardiogenic shock. For all the patients, the Simplified Acute Physiology Score II, cardiac index, cardiac power index, and continuous hemodynamic values following the first 24 hours of admission were reviewed. Mortality within 28 days was the primary endpoint. All the variables were then compared with survival and nonsurvival status and those variables with a significant association in the univariate analysis were entered into a multivariate logistic regression model. Seventy-one patients were included. Among them, 26 (37%) died within 28 days after ICU admission and were classified as "nonsurvivors." The minimum value for diastolic arterial blood pressure during the first 24 hours was independently associated with the 28-day mortality in the univariate and multivariate analyses model. This model performed better than the model using the Simplified Acute Physiology Score II, even when assessing the effect of inotrope and vasoactive treatments at 24, 48, and 72 hours. In the first 24 hours of an ICU admission, the minimum diastolic arterial blood pressure was a hemodynamic variable that was independently associated with 28-day mortality in cardiogenic shock patients.

Auditing secondary prevention prescribing following Coronary Artery Bypass Grafting (CABG)

Auditing secondary prevention prescribing following Coronary Artery Bypass Grafting (CABG)

Ambulatory blood pressure changes and predictors of response in patients undergoing renal sympathetic denervation

Background: Ambulatory blood pressure monitoring (ABPM) is important to identify hypertensive patients at risk. Catheter-based renal sympathetic denervation (RDN) reduces office blood pressure (BP) in patients with resistant hypertension according to office BP. Less is known about the effect of RDN on 24-hour BP and predictors of response in individuals with true or pseudo-resistant hypertension. Methods and results: A total of 346 uncontrolled hypertensive patients (office systolic BP ≥160 mmHg, ≥150 mmHg for type 2 diabetes), separated according to daytime ABPM into 303 with true resistant (office SBP 172.2±1.4 mmHg; 24-hour mean SBP 154±0.9 mmHg) and 43 with pseudo-resistant hypertension (office SBP 161.2±3.3 mmHg; 24-hour mean SBP 121.1±3 mmHg), from 10 centers were studied. Office systolic, diastolic and pulse pressure (SBP/DBP/PP) and ABPM (including daytime, nighttime, maximum, minimum BP) were measured at entry, and at 3, 6 and 12 months following RDN. At 3, 6 and 12 months follow-up office SBP was reduced by 21.5/23.7/27.3 mmHg, DBP by 8.9/9.5/11.7 mmHg, and PP by 13.4/14.2/14.9 mmHg (n=245/236/90; p for all <0.001), respectively. In patients with true treatment resistance there was a significant reduction with RDN in 24-hour mean SBP (-10.1/-10.2/-11.7 mmHg, p<0.001), DBP (-4.8/-4.9/-7.4 mmHg, p<0.001), maximum SBP (-11.7/-10.0/-6.1 mmHg, p<0.001) and minimum SBP (-6.0/-9.4/-13.1 mmHg, p<0.001) at 3, 6 and 12 months, respectively. There was no effect on ABPM in pseudo-resistant patients, while office BP was reduced to a similar extent. RDN was equally effective in reducing BP in different subgroups of patients (age, eGFR, dipping pattern, diabetic status, etc). Office SBP at baseline was the only independent predictor of BP response. Conclusions: RDN reduced office SBP, DBP, PP, ABPM average, daytime, nighttime, maximum and minimum BP in patients with true-treatment resistant hypertension. Our data from the largest cohort of patients treated by RDN and followed with ABPM up to 12 months demonstrate that in patients with true resistant hypertension the procedure improves relevant aspects of ABPM commonly linked to high cardiovascular risk, while it only affected office BP in pseudo-resistant hypertension.

Association between uric acid levels and obstructive sleep apnea syndrome in a large epidemiological sample.

IntroductionRecurrent hypoxia, which is associated with obstructive sleep apnea syndrome (OSAS), leads to an increase in the degradation of adenosine triphosphatase into xanthine, which in turn increases uric acid concentrations.ObjectiveThe current study aimed to determine whether an association exists between OSAS and uric acid levels in the peripheral blood from a representative population of Sao Paulo (Brazil).MethodsA population-based survey adopting a probabilistic 3-stage cluster sample of Sao Paulo was used to represent the population according to gender, age, and socioeconomic class. A total of 1,042 volunteers underwent polysomnography recordings for OSAS diagnosis, blood pressure assessment, and biochemical blood analysis, and answered questionnaires.ResultsUric acid levels were correlated with most important risk factors for OSAS, such as AHI, desaturation time and index, minimum oxyhemoglobin saturation (SpO2), blood pressure, cholesterol, BMI, triglycerides and arousal, and with OSAS itself. Also, uric acid was increased in OSAS volunteers even after controlling for all confounders. Hyperuricemic volunteers presented lower mean and minimum SpO2 and increased desaturation index. Importantly, minimum SpO2 was a significant predictor of uric acid levels, which in turn was considered an independent predictor for OSAS in the binary logistic model. However, a ROC curve analysis for establishing cut-off points for uric acid levels as a biomarker of OSAS revealed moderate sensitivity and specificity.ConclusionA strong association was found between uric acid levels and OSAS in a representative sample of the population of Sao Paulo. Although they do not qualify for a biomarker alone, uric acid levels may be involved in OSAS severity and should be considered in sleep apnea management in the future.

Sleep Duration and Insomnia in the Elderly: Associations With Blood Pressure Variability and Carotid Artery Remodeling

Recent studies have shown that short and long sleep durations and insomnia are associated with increased home-measured blood pressure (BP) variability, which in turn has a relationship with arterial stiffness. However, the determinants for visit-to-visit systolic blood pressure (SBP) variability have rarely been investigated in relation to sleep duration, insomnia, and carotid arterial stiffness. The subjects were 201 elderly individuals (79.9±6.4 years old) with one or more cardiovascular risks. Based on 12 visits, visit-to-visit BP variability (expressed as a coefficient of variation [CV]) and δ (maximum - minimum) BP were measured. Self-reported sleep duration and insomnia questionnaires were used to classify the patients according to sleep duration period and insomnia status. After multivariable adjustment, long sleep duration (≥ 9 hours per night) had significant positive associations with SBP δ (P < 0.05), while persistent insomnia had significant positive associations with SBP CV (P < 0.05) and δ (P < 0.01). Additionally, significant interactions were found in terms of long sleep duration by carotid artery stiffness parameter β (P < 0.05), persistent insomnia by intima-media thickness (P < 0.01), and persistent insomnia by stiffness parameter β (P < 0.05) for SBP δ. In elderly patients at high risk for cardiovascular disease, long sleep duration as well as persistent insomnia were significantly associated with higher visit-to-visit BP variability. Long sleep duration and persistent insomnia each had synergetic interactions with carotid artery stiffness and with visit-to-visit BP variability.

Clinical presentations and outcomes of systemic lupus erythematosus patients with infection admitted to the intensive care unit

The objective of this article is to investigate clinical presentations and outcomes of systemic lupus erythematosus (SLE) patients with infection admitted to the intensive care unit (ICU). SLE patients with infection, SLE patients with noninfectious causes, and non-SLE patients with infection were identified from the Cooper University Hospital Project IMPACT database between 2002 and 2010. We examined demographic data, APACHE II scores, physiologic data, laboratory data, length of stay in the ICU and hospital, and mortality of the three groups. Twenty-five SLE patients with infection, 45 SLE patients with noninfectious causes, and 1466 non-SLE patients with infection were included in the study. SLE patients with infection had higher APACHE II scores, higher maximum temperature, higher minimum and maximum heart rate (HR), lower minimum and maximum systolic blood pressure (SBP), and longer ICU length of stay in comparison to SLE patients with noninfectious causes. There were no statistical differences in white blood cell (WBC) count. SLE patients with infection had a higher mortality compared to SLE patients with noninfectious causes. There was no difference in mortality between SLE patients with infection and non-SLE patients with infection. SLE patients with infection in the ICU had a higher mortality and a higher APACHE II score compared to SLE patients with noninfectious causes in the ICU. Their physiologic signs including temperature, HR, and SBP were more reflective of infection than their WBC count.

Impact of blood pressure changes and course on hematoma growth in acute intracerebral hemorrhage

An association between high blood pressure (BP) in acute intracerebral hemorrhage (ICH) and hematoma growth (HG) has not been clearly demonstrated. Therefore, the impact of BP changes and course on HG and clinical outcome in patients with acute ICH was determined. In total, 117 consecutive patients with acute (<6 h) supratentorial ICH underwent baseline and 24-h CT scans, CT angiography for the detection of the spot sign and non-invasive BP monitoring at 15-min intervals over the first 24 h. Maximum and minimum BP, maximum BP increase and drop from baseline, and BP variability values from systolic BP (SBP), diastolic BP and mean arterial pressure (MAP) were calculated. SBP and MAP loads were defined as the proportion of readings >180 and >130 mmHg, respectively. HG (>33% or >6 ml), early neurological deterioration (END) and 3-month mortality were recorded. Baseline BP variables were unrelated to either HG or clinical outcome. Conversely, SBP 180-load independently predicted HG (odds ratio 1.05, 95% CI 1.010-1.097, P = 0.016), whilst both SBP 180-load (odds ratio 1.04, 95% CI 1.001-1.076, P = 0.042) and SBP variability (odds ratio 1.2, 95% CI 1.047-1.380, P = 0.009) independently predicted END. Although none of the BP monitoring variables was associated with HG in the spot-sign-positive group, higher maximum BP increases from baseline and higher SBP and MAP loads were significantly related to HG in the spot-sign-negative group. In patients with acute supratentorial ICH, SBP 180-load independently predicts HG, whilst both SBP 180-load and SBP variability predict END.

Educational Exhibit Abstract No. 372 - Intraoperative major trauma embolization: initial experience and TIPS for success in establish a hemorrhage control team

Learning Objectives To outline basic selection criteria for intra-operative vs IR suite embolization. To review some pitfalls and roadblocks to success. Discuss keys for prompt response time and short procedural times. Background A subset of severe poly-trauma patients are too unstable to be successfully imaged by CT and transferred to the IR suite. These patients require urgent transfer to the OR for stabilization and support. Nonetheless, some of these patients can benefit from embolization intra-operatively, as certain pelvic and parenchymal organ hemorrhage may be easier to control angiographically than surgically. Clinical Findings/Procedure Details Basic materials required required for intra-operative angiography will be outlined as well as strategies to reduce response and procedure time. Conclusion and/or Teaching Points Intra-operative angiographic hemorrhage control has become an essential part of our Trauma team. It is especially useful in those patients with such massive hemorrhage and severe hemodynamic instability that transfer to an OR setting is required just to maintain a minimum blood pressure. High clinical success rates are achievable despite challenging technical conditions.

Low Diastolic Blood Pressure as a Risk for All-Cause Mortality in VA Patients

Background. A paradoxical increase in cardiovascular events has been reported with intensively lowering diastolic blood pressure (DBP). This J-curve phenomenon has challenged the aggressive lowering of blood pressure, especially in patients with coronary artery disease. Objective. Our objective was to study the effects of low DBP on mortality and determine a threshold for which DBP should not be lowered beyond. Methods. We evaluated a two-year cross-section of primary care veteran patients, from 45 to 85 years of age. Receiver operating characteristics (ROC) were employed to establish an optimal cut-off point for DBP. Propensity-score matching and multivariate logistic regression were used to control for confounders. All-cause mortality was the primary outcome. Results. 14,270 patients were studied. An ROC curve found a threshold value of DBP 70 mmHg had the greatest association with mortality (P < 0.001). 49% of patients had a DBP of 70 mmHg or less. Using a propensity-matched multivariate logistic regression, odds ratio for all-cause mortality in subjects with a DBP less than 70 mmHg was 1.5 (95% CI 1.3–1.8). Conclusions. Reduction of DBP below 70 mmHg is associated with increased all-cause mortality. Hypertension guidelines should include a minimum blood pressure target.

Risk factors for stroke among patients with hypertension: A case–control study

BackgroundIn some African countries, more than half of the adult population are estimated to be hypertensive leading to an escalated burden of stroke in the continent. We conducted the first study to unravel the major risk factors for stroke among hypertensive patients (Nigerian-Africans) using a case–control design while also exploring the relative contributions of carotid intima medial thickness (CIMT) and carotid diameter as risk markers for stroke. MethodsUsing conventional techniques, stroke-related demographic, clinical and laboratory data were obtained from 135 consecutive volunteering hypertensive stroke patients and compared with 117 age and gender-matched hypertensive patients with no clinical evidence of stroke, TIA or coronary artery disease. Common carotid IMT and diameters were measured in all participants. Univariate and multivariate analyses were conducted at p=0.05. Results13.2% of the stroke patients were first diagnosed as hypertensive at presentation with stroke. Among hypertensive patients, the modifiable factors significantly (p<0.00001 to p<0.037) associated with stroke occurrence included higher maximum and minimum blood pressures in the preceding 3months, higher fasting plasma glucose, greater alcohol consumption, lesser physical activity and increased CIMT. Using a multivariate model which predicted 84.6% of stroke occurrence, only fasting total cholesterol of >150mg/dl (p=0.021) and common carotid diameter of ≥5.9mm (p=0.008) independently multiplied the risk of stroke. ConclusionsParticularly in resource-limited settings, aside from BP control, stroke prevention efforts should be targeted towards these identified risk factors for stroke among hypertensive patients. Carotid diameter should be further explored as an intermediate risk marker for stroke.

Home Blood Pressure Variability as Cardiovascular Risk Factor in the Population of Ohasama

Blood pressure variability based on office measurement predicts outcome in selected patients. We explored whether novel indices of blood pressure variability derived from the self-measured home blood pressure predicted outcome in a general population. We monitored mortality and stroke in 2421 Ohasama residents (Iwate Prefecture, Japan). At enrollment (1988-1995), participants (mean age, 58.6 years; 60.9% women; 27.1% treated) measured their blood pressure at home, using an oscillometric device. In multivariable-adjusted Cox models, we assessed the independent predictive value of the within-subject mean systolic blood pressure (SBP) and corresponding variability as estimated by variability independent of the mean, difference between maximum and minimum blood pressure, and average real variability. Over 12.0 years (median), 412 participants died, 139 of cardiovascular causes, and 223 had a stroke. In models including morning SBP, variability independent of the mean and average real variability (median, 26 readings) predicted total and cardiovascular mortality in all of the participants (P≤0.044); variability independent of the mean predicted cardiovascular mortality in treated (P=0.014) but not in untreated (P=0.23) participants; and morning maximum and minimum blood pressure did not predict any end point (P≥0.085). In models already including evening SBP, only variability independent of the mean predicted cardiovascular mortality in all and in untreated participants (P≤0.046). The R(2) statistics, a measure for the incremental risk explained by adding blood pressure variability to models already including SBP and covariables, ranged from <0.01% to 0.88%. In a general population, new indices of blood pressure variability derived from home blood pressure did not incrementally predict outcome over and beyond mean SBP.

Within-Subject Blood Pressure Level—Not Variability—Predicts Fatal and Nonfatal Outcomes in a General Population

To assess the prognostic significance of blood pressure (BP) variability, we followed health outcomes in a family-based random population sample representative of the general population (n=2944; mean age: 44.9 years; 50.7% women). At baseline, BP was measured 5 times consecutively at each of 2 home visits 2 to 4 weeks apart. We assessed within-subject overall (10 readings), within- and between-visit systolic BP variability from variability independent of the mean, the difference between maximum and minimum BP, and average real variability. Over a median follow-up of 12 years, 401 deaths occurred and 311 participants experienced a fatal or nonfatal cardiovascular event. Overall systolic BP variability averaged (SD) 5.45 (2.82) units, 15.87 (8.36) mmHg, and 4.08 (2.05) mmHg for variability independent of the mean, difference between maximum and minimum BP, and average real variability, respectively. Female sex, older age, higher-mean systolic BP, lower body mass index, a history of peripheral arterial disease, and use of β-blockers were the main correlates of systolic BP variability. In multivariable-adjusted analyses, overall and within- and between-visit BP variability did not predict total or cardiovascular mortality or the composite of any fatal plus nonfatal cardiovascular end point. For instance, the hazard ratios for all cardiovascular events combined in relation to overall variability independent of the mean, difference between maximum and minimum BP, and average real variability were 1.05 (0.96-1.15), 1.06 (0.96-1.16), and 1.08 (0.98-1.19), respectively. By contrast, mean systolic BP was a significant predictor of all end points under study, independent of BP variability. In conclusion, in an unbiased population sample, BP variability did not contribute to risk stratification over and beyond mean systolic BP.

509 L-CITRULLINE SUPPLEMENTATION REDUCED PERIPHERAL BLOOD PRESSURE IN CHINESE ADULTS WITH PREHYPERTENSION

Background: Prehypertension is a growing problem worldwide, and in Caucasian samples certain fruits or their supplements have demonstrated success in improving blood pressure. The aim of this study was to investigate the effect and mechanism of L-citrulline in regulating blood pressure among Chinese adults with prehypertension. Methods: From 369 patients attending a free physical examination, 40 prehypertensive participants were identified and randomly allocated to: an intervention group who received one-to-one health education plus 3 g L-citrulline; and a control group gave a placebo, both twice a day. 24-hour ambulatory blood pressure was collected at baseline and eight weeks later and concentration of nitric oxide synthase at eight weeks later. Results: L-citrulline reduced the maximum, minimum and office systolic blood pressure; the maximum diastolic blood pressure (p < 0.05); and maximum mean arterial pressure (p < 0.01). No significant effects were noted for the remaining blood pressure values notably the minimum diastolic blood pressure. Concentration of nitric oxide synthase was significantly up-regulated in the intervention group (p < 0.05) (Table 1).Conclusions: The results showed that L-citrulline automatically regulated blood pressure via improved nitric oxide production in Chinese adults with prehypertension.