Prognostic Relevance of Short-Term Blood Pressure Variability. The Spanish ABPM Registry

BACKGROUND

The prognostic relevance of short-term blood pressure (BP) variability in hypertension is not clearly established. We aimed to evaluate the association of short-term BP variability, with all-cause and cardiovascular mortality in a large cohort of patients with hypertension.

METHODS

We selected 59 124 patients from the Spanish Ambulatory Blood Pressure Monitoring Registry from 2004 to 2014 (median follow-up: 9.7 years). Systolic and diastolic BP SD and coefficient of variation from daytime and nighttime, weighted SD, weighted coefficient of variation, average real variability (mean of differences between consecutive readings), and BP variability ratio (ratio between systolic and diastolic 24-hour SD) were calculated through baseline 24-hour ambulatory BP monitoring. Association with all-cause and cardiovascular mortality were assessed by Cox regression models adjusted for clinical confounders and BP.

RESULTS

Patients who died during follow-up had higher values of BP variability compared with those remaining alive. In adjusted models systolic and diastolic daytime and weighted SD and coefficient of variation, average real variability, as well as systolic nighttime SD and BP variability ratio were all significantly associated with all-cause and cardiovascular mortality. Hazard ratios for 1-SD increase in the systolic components ranged from 1.05 to 1.12 for all-cause mortality and from 1.07 to 1.17 for cardiovascular mortality. A daytime SD≥13 mm Hg, a nighttime and a weighted SD≥12 mm Hg, and an average real variability ≥10 mm Hg, all systolic, were independently associated with mortality.

CONCLUSIONS

Short-term blood pressure variability shows a relatively weak but significant association with all-cause and cardiovascular mortality in patients with hypertension.

Predictive power of 24-h ambulatory pulse pressure and its components for mortality and cardiovascular outcomes in 11 848 participants recruited from 13 populations

BACKGROUND

The role of pulse pressure (PP) 'widening' at older and younger age as a cardiovascular risk factor is still controversial. Mean PP, as determined from repeated blood pressure (BP) readings, can be expressed as a sum of two components: 'elastic PP' (elPP) and 'stiffening PP' (stPP) associated, respectively, with stiffness at the diastole and its relative change during the systole. We investigated the association of 24-h ambulatory PP, elPP, and stPP ('PP variables') with mortality and composite cardiovascular events in different age classes.

METHOD

Longitudinal population-based cohort study of adults with baseline observations that included 24-h ambulatory BP. Age classes were age 40 or less, 40-50, 50-60, 60-70, and over 70 years. Co-primary endpoints were total mortality and composite cardiovascular events. The relative risk expressed by hazard ratio per 1SD increase for each of the PP variables was calculated from multivariable-adjusted Cox regression models.

RESULTS

The 11 848 participants from 13 cohorts (age 53 ± 16 years, 50% men) were followed for up for 13.7 ± 6.7 years. A total of 2946 participants died (18.1 per 1000 person-years) and 2093 experienced a fatal or nonfatal cardiovascular event (12.9 per 1000 person-years). Mean PP, elPP, and stPP were, respectively, 49.7, 43.5, and 6.2 mmHg, and elPP and stPP were uncorrelated ( r  = -0.07). At age 50-60 years, all PP variables displayed association with risk for almost all outcomes. From age over 60 years to age over 70 years, hazard ratios of of PP and elPP were similar and decreased gradually but differently for pulse rate lower than or higher than 70 bpm, whereas stPP lacked predictive power in most cases. For age 40 years or less, elPP showed protective power for coronary events, whereas stPP and PP predicted stroke events. Adjusted and unadjusted hazard ratio variations were similar over the entire age range.

CONCLUSION

This study provides a new basis for associating PP components with outcome and arterial properties in different age groups and at different pulse rates for both old and young age. The similarity between adjusted and unadjusted hazard ratios supports the clinical usefulness of PP components but further studies are needed to assess the prognostic significance of the PP components, especially at the young age.

Relative and Absolute Risk to Guide the Management of Pulse Pressure, an Age-Related Cardiovascular Risk Factor

BACKGROUND

Pulse pressure (PP) reflects the age-related stiffening of the central arteries, but no study addressed the management of the PP-related risk over the human lifespan.

METHODS

In 4,663 young (18-49 years) and 7,185 older adults (≥50 years), brachial PP was recorded over 24 hours. Total mortality and all major cardiovascular events (MACEs) combined were coprimary endpoints. Cardiovascular death, coronary events, and stroke were secondary endpoints.

RESULTS

In young adults (median follow-up, 14.1 years; mean PP, 45.1 mm Hg), greater PP was not associated with absolute risk; the endpoint rates were ≤2.01 per 1,000 person-years. The adjusted hazard ratios expressed per 10-mm Hg PP increments were less than unity (P ≤ 0.027) for MACE (0.67; 95% confidence interval [CI], 0.47-0.96) and cardiovascular death (0.33; 95% CI, 0.11-0.75). In older adults (median follow-up, 13.1 years; mean PP, 52.7 mm Hg), the endpoint rates, expressing absolute risk, ranged from 22.5 to 45.4 per 1,000 person-years and the adjusted hazard ratios, reflecting relative risk, from 1.09 to 1.54 (P < 0.0001). The PP-related relative risks of death, MACE, and stroke decreased >3-fold from age 55 to 75 years, whereas absolute risk rose by a factor 3.

CONCLUSIONS

From 50 years onwards, the PP-related relative risk decreases, whereas absolute risk increases. From a lifecourse perspective, young adulthood provides a window of opportunity to manage risk factors and prevent target organ damage as forerunner of premature death and MACE. In older adults, treatment should address absolute risk, thereby extending life in years and quality.

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

BACKGROUND

Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories.

METHODS

We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age.

FINDINGS

The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran.

INTERPRETATION

Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings.

FUNDING

WHO.

Abnormal liver tests in patients with SARS-CoV-2 or influenza - prognostic similarities and temporal disparities

Background & Aims

Abnormal liver tests are common in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but a possible direct role of the virus in liver injury and its association with short-term outcomes are controversial. Therefore, we aimed to compare the pattern of abnormal liver tests in patients with SARS-CoV-2 with those of patients infected with influenza, a non-hepatotropic respiratory virus, and their association with worse outcomes during hospitalisation.

Methods

We performed a retrospective cohort study of 1,737 hospitalised patients (865 with influenza and 872 with SARS-CoV-2) in a tertiary medical centre. We defined abnormal liver tests as alanine transaminase or aspartate transaminase ≥40 IU/ml at any time-point during hospitalisation.

Results

Abnormal liver tests were mild to moderate in most patients regardless of infection type, but the majority of patients with influenza had a transaminase peak earlier during hospitalisation compared with patients with SARS-CoV-2. Abnormal liver tests correlated with markers of severe disease in either influenza or SARS-CoV-2 infections, and were associated with death, occurring mainly in patients with severe liver test abnormalities (>200 IU/L) (38.7% and 60% of patients with influenza or SARS-CoV-2, respectively). In multivariate analysis, controlling for age, sex, lymphopaenia, and C-reactive protein, liver test abnormalities remained significantly associated with death for influenza (odds ratio 4.344; 95% CI 2.218-8.508) and SARS-CoV-2 (odds ratio 3.898; 95% CI 2.203-6.896). These results were confirmed upon propensity score matching.

Conclusions

Abnormal liver tests during hospitalisation with SARS-CoV-2 or influenza infections are common, may differ in their time course, and reflect disease severity. They are associated with worse outcomes, mainly in patients with severe liver test abnormalities, regardless of infection type.

Lay summary

Coronavirus disease 2019 (COVID-19) is a serious global health pandemic, the causative agent of which is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Abnormal liver tests are common among SARS-CoV-2 infected patients and are often associated with worse outcomes. Herein, we compare the pattern of abnormal liver tests and their association with disease severity between 2 major non-hepatotropic respiratory viruses: SARS-CoV-2 and influenza. We show that abnormal liver tests are common in both infections, may slightly differ in their kinetics, and are associated with worse outcomes, especially in patients with severe liver test abnormalities. These results strongly suggest that abnormal liver tests in SARS-CoV-2 patients reflect disease severity, rather than a virus-mediated direct liver injury, and should be closely followed in admitted patients.

Uveitis intermedia as the initial presentation of a primary lymphoma of the central nervous system

Primary central nervous system lymphoma is one of the most infrequent brain tumours, accounting for 3% of primary central nervous system neoplasms. In addition to its low prevalence, clinical presentation is usually nonspecific, leading to diagnostic delay. Intraocular involvement occurs in 15% of cases, and disease onset in this location is even rarer. We present a case of a patient with intermediate uveitis as the first clinical manifestation of this neoplasm.

Birth Weight and Maternal Body Size as Determinants of Blood Pressure at Age 17: Results from the Jerusalem Perinatal Study Cohort

OBJECTIVES

To investigate the effect of birth weight (BW) and maternal pre-pregnancy BMI (mBMI) on blood pressure (BP) in adolescence.

METHODS

A Population-based cohort of 11,729 births in Jerusalem during 1974-1976, with archival data on maternal and birth characteristics was performed. Measurements at age 17 were assessed and linear regression models were used to evaluate the associations of birth characteristics with BP outcomes.

RESULTS

BW was inversely associated with both systolic (SBP) and diastolic (DBP) BP at age 17 (SBP: B = - 0.829, p = 0.002; DBP: B = - 0.397, p = 0.033). The interaction term between BW and weight at age 17 was significant for DBP (p = 0.017) and pulse pressure (p = 0.005). mBMI yielded significant positive associations with BP, independent of BW.

CONCLUSIONS FOR PRACTICE

Our findings indicate that there are at least two distinct pathways linking early life characteristics with subsequent BP: Intrauterine growth, as reflected by BW and other genetic or environmental factors, reflected by mBMI and maternal education, contribute to offspring adolescent BP. These results warrant replication in other birth cohorts and underline the need to explore specific mechanisms that account for these associations.

Tamoxifen retinal toxicity. Monitoring by multimodal imaging study

INTRODUCTION

Tamoxifen is a non-steroidal anti-oestrogen that acts as an antagonist in breast tissue, neurosensory retina, and retinal pigment epithelium (RPE). The reported incidence of its ocular effects varies between 0.9% and 11%.

METHODS

Case series. Multimodal image studies were used to evaluate three female patients who were receiving tamoxifen for breast cancer for the purpose of monitoring and determining whether there are changes after discontinuation of treatment.

RESULTS

All three patients showed signs of crystalline retinopathy using spectral domain optical coherence tomography (SD-OCT) during follow-up.

CONCLUSION

The follow-up using multimodal imaging studies allowed evaluating the progression of the changes, providing a prognostic assessment. The findings reported (visual acuity and multimodal imaging) confirmed the results of previous studies, indicating that, at a certain level of toxicity, the damage was irreversible.

Aberrant corin and PCSK6 in placentas of the maternal hyperinsulinemia IUGR rat model

OBJECTIVES

Corin is a protease that converts pro-atrial natriuretic peptide (pro-ANP) to ANP. While the involvement of ANP in the cardiovascular regulation is well established, there is increasing evidence that the pregnant uterus produces ANP, which promotes spiral artery remodeling. The present study examines the alterations in corin and PCSK6, a key enzyme in the conversion of pro-corin to corin, in the placenta of hyperinsulinemic dams (HD) featuring pregnancy-induced hypertension (PIH).

MATERIALS AND METHODS

The study was conducted on female Wistar rats. Rats were rendered hyperinsulinemic by subcutaneous insulin pellet, mated and followed to the twenty-first day of pregnancy. Normal pregnant dams (NPD) served as controls. Both groups were sacrificed on day 21 of gestation and their placentas were dissected along with the mesometrial triangle (MT). The tissue was then sectioned from the maternal surface to the base of the MT, and processed for histological and molecular biology analysis of Corin, PCSK6 and ANP expression/immunoreactivity.

RESULTS

Hyperinsulinemic dams developed PIH, along lower placental and fetal weights. Corin expression and immunoreactivity were significantly decreased in the placenta by ~40-50%, but not in the MT. Similarly, placental but not MT PCSK6 immunoreactivity was lower in HD. Concomitantly with the downregulation of corin/PCSK6, proANP levels increased in the placenta of HD.

CONCLUSIONS

Corin and PCSK6 are expressed in the placenta and MT. The decline in these two enzymes in the placenta of HD suggests a role of corin/PCSK6 machinery in the development of PIH and intrauterine growth restriction characterizing hyperinsulinemia.

Overnight/first-morning urine free metanephrines and methoxytyramine for diagnosis of pheochromocytoma and paraganglioma: is this an option?

OBJECTIVE

Sympathoadrenal activity is decreased during overnight rest. This study assessed whether urinary-free normetanephrine, metanephrine and methoxytyramine in overnight/first-morning urine collections might offer an alternative to measurements in 24-h collections or plasma for diagnosis of pheochromocytoma and paraganglioma (PPGL).

DESIGN AND METHODS

Prospective multicenter cross-sectional diagnostic study involving 706 patients tested for PPGL, in whom tumors were confirmed in 79 and excluded in 627 after follow-up. Another 335 age- and sex-matched volunteers were included for reference purposes. Catecholamines and their free O-methylated metabolites were measured in 24-h collections divided according to waking and sleeping hours and normalized to creatinine. Plasma metabolites from blood sampled after supine rest were measured for comparison.

RESULTS

Urinary outputs of norepinephrine, normetanephrine, epinephrine and metanephrine in the reference population were respectively 50 (48-52)%, 35 (32-37)%, 76 (74-78)% and 15 (12-17)% lower following overnight than daytime collections. Patients in whom PPGLs were excluded showed 28 (26-30)% and 6 (3-9)% day-to-night falls in normetanephrine and metanephrine, while patients with PPGLs showed no significant day-to-night falls in metabolites. Urinary methoxytyramine was consistently unchanged from day to night. According to receiver-operating characteristic curves, diagnostic accuracy of metabolite measurements in overnight/first-morning urine samples did not differ from measurements in 24-h urine collections, but was lower for both than for plasma. Using optimized reference intervals, diagnostic specificity was higher for overnight than daytime collections at similar sensitivities.

CONCLUSIONS

Measurements of urinary-free catecholamine metabolites in first-morning/overnight urine collections offer an alternative for diagnosis of PPGL to 24-h collections but remain less accurate than plasma measurements.

Prognostic Relevance of Short-Term Blood Pressure Variability: The Spanish ABPM Registry

The prognostic relevance of short-term blood pressure (BP) variability in hypertension is not clearly established. We aimed to evaluate the association of short-term BP variability, assessed through ambulatory BP monitoring, with total and cardiovascular mortality in a large cohort of patients with hypertension. We selected 63 910 subjects from the Spanish ABPM Registry from 2004 to 2014, with a median follow-up of 4.7 years. Systolic and diastolic BP SD from 24 hours, daytime, and nighttime, weighted SD (mean of daytime and nighttime SD weighted for period duration), average real variability (mean of differences between consecutive readings), variation independent of the mean, and BP variability ratio (ratio between systolic and diastolic 24-hour SD) were calculated through 24-hour ambulatory BP monitoring performed at baseline. Association with total and cardiovascular mortality (obtained through death certificates) were assessed by Cox regression models adjusted for clinical confounders and BP. Patients who died during follow-up had higher values of BP variability compared with those remaining alive. In fully adjusted models, daytime, nighttime, and weighted SD, systolic and diastolic, as well as diastolic average real variability, were all significantly associated with total and cardiovascular mortality. Hazard ratios for 1 SD increase ranged from 1.05 to 1.09 for total mortality and from 1.07 to 1.12 for cardiovascular mortality. A nighttime systolic SD ≥12 mm Hg was independently associated with total (hazard ratio: 1.13 [95% CI, 1.06-1.21]) and cardiovascular mortality (hazard ratio: 1.21 [95% CI, 1.09-1.36]). We conclude that short-term BP variability is independently associated with total and cardiovascular mortality in patients with hypertension.

Fasting-Induced Natriuresis and SGLT: A New Hypothesis for an Old Enigma

For years, physicians and scientists were enthralled by the enigmatic phenomenon of fasting-associated diuresis and natriuresis and their reversal by feeding. This abrupt response is most prominent in obese and hypertensive individuals, and if repeated once and again may lead to the attenuation of blood pressure and improve insulin sensitivity. The mechanisms involved in early natriuresis and diuresis remain speculative as the renin-angiotensin-aldosterone axis and natriuretic peptides are initially suppressed. Based on gained insight using sodium-glucose transporter 2 (SGLT-2) inhibitors, herein, we propose a role for enhanced post-prandial proximal tubular sodium uptake, mediated by increased glucose-sodium co-transport, as daily filtered glucose increases, and reduced sodium uptake when glucose reabsorption diminishes. This phenomenon might be more pronounced in diabetics due to prolonged post-prandial hyperglycemia and intense SGLT-driven transport. Our hypothesis may also provide a physiologic basis for fasting-related reduced blood pressure in hypertension. This theory deserves challenging by experimental and clinical studies.

Abstract P2053: Blood Pressure Variability is Higher When Pulse Rate is Lower, in a Large Outpatient Database

Historically, guidelines for blood pressure measurement recommended adjusting the cuff deflation rate to the patient's heart rate (2-3 mmHg per heartbeat).Current guidelines recommend a fixed cuff deflation rate of 2 mmHg/sec.. In this study, we assess the association between pulse rate (PR) and BP variability. All BP measurements in adult patients with corresponding PR documentation were reviewed in a large outpatient database. In each category (6 categories between 40 and 99 bpm), patients with at least 3 BP readings within that category were included. In each category, systolic and diastolic BP coefficient of variance (corrected for sample size) was plotted against the PR category. There were 551,595 unique patients with a total of 4,760,000 measurements, and 860,522 groups of 3 measurements or more per patient within a PR category. BP normalized coefficient of variance was inversely related to PR (Figure), ranging 0.0043 to 0.0003 (Systolic), and 0.0024 to 0.0002 (Diastolic), for the lowest to highest heart rate category, respectively. BP variability is inversely associated with PR, especially in lower PR, likely reflecting less precise BP measurements where the "sample size" of pulse is small. The observed effect compromising precision might be accompanied by a concomitant reduced accuracy of BP measurement which is another theoretical implication of a smaller "sample size", leading to a systematic bias towards measuring lower and higher than real systolic and diastolic BP respectively.

Ambulatory pulse pressure components: concept, determination and clinical relevance

BACKGROUND

Ambulatory pulse pressure (PP) a well known predictor of mortality, is widely believed to be a marker for arterial stiffness. However stiffness itself is pressure-dependent.

OBJECTIVES

Developing a model-based method for splitting PP into two components expressing the contribution of a pressure-independent stiffness ('elastic', elPP) and the pressure-dependence of stiffness ('stiffening', stPP), and investigating their predictive power for all-cause mortality.

METHODS

Deriving quantitative expressions for elPP and stPP assuming an exponential pressure-volume relationship in arteries, calculated from ambulatory blood pressure (BP) data and estimate standardized hazard ratios with Cox proportional hazards regression in selected patient groups.

RESULTS

Ambulatory BP records of 1999 consecutive hypertensive patients, of whom 103 died from all causes within 5 years, were analyzed. PP, elPP, stPP and stPP/elPP (PP variables) (mean ± SD) were 60 ± 14, 50 ± 10, 10 ± 8 and 0.20 ± 0.14 mmHg, respectively. elPP and stPP were weakly correlated (r = 0.21). Predictive power was found for patients with heart rate less than 70: mean [95% confidence interval] (P value) hazard ratio of PP, stPP and stPP/elPP (adjusted) were 1.48 [1.13-1.95] (P = 0.005), 1.58 [1.20-2.09] (P = 0.001) and 1.78 [1.25-2.52] (P = 0.001), respectively. The elPP (83% of PP) did not show predictive power. None of the PP variables displayed predictive power for the higher-heart-rate subgroup.

CONCLUSION

Ambulatory PP components provide a novel and clinically valuable tool bridging between PP and arterial properties. Replacing PP by its components, taken as independent variables, may improve predictive power. The prognostic significance of the PP for all-cause mortality in elderly hypertensive patients with lower heart rates is dominated by its smaller component that quantifies arterial stiffening with pressure.

Abstract P309: Aberrant Corin and PCSK6 in the Placenta of Hyperinsulinemic Dams

Introduction: Corin, a serine protease converts pro-atrial natriuretic peptide (pro-ANP) and pro-brain natriuretic peptide (pro-BNP) to the mature respective peptides. There is evidence that the pregnant uterus produces ANP, where it promotes spiral artery remodelling, essential for adequate blood supply to the developing conceptus.

Aim: Here we examine corin and PCSK6, a key enzyme in the conversion of pro-corin to corin, in the placenta of hyperinsulinemic dams (HD) in comparison to normal pregnant dams (NPD).

Materials and Methods: Female Wistar rats were rendered hyperinsulinemic by subcutaneous insulin pellet, mated and followed to day 21 of pregnancy. Both groups were then sacrificed and their placentas were dissected together with the implantation site designated mesometrial triangle (MT). Placentas and MT were sectioned from the maternal through the fetal surface to the base of the MT. For western blot (WB) the placentas and MT were separated, snap frozen in liquid nitrogen and stored at –80°C. RNA expression of corin was carried out by in-situ hybridization in 5 NPD and 6 HD with corin probe (RNAscope® Assay 2.5 Detection Reagent, Cat No. 507231) and image analysis was performed.

Results: As previously described, HD (n=20) developed hypertension as compared with in NPD (n=16). Moreover, HD exhibited lower placental and foetal weights. Corin and PCSK6 mRNA and immunoreactive peptide were detected in the mesometrial tissues. Corin abundance as determined by western blot was significantly decreased in the placenta/ mesometrial triangle by ~40% (P<0.02), as was PCSK6 immunoreactivity. Corin and PCSK6 mRNAs displayed similar pattern of alterations as protein abundance, where in-situ hybridization for corin mRNA revealed a 50% (P<0.001) expression reduction. Corin mRNA was specifically expressed by cytotrophoblasts in the labyrinth. Concomitant with the downregulation of corin/PCSK6, ANP levels decreased in the MT of HD.

Summary and Conclusion: Corin, PCSK6 and ANP are all expressed in the placenta of NPD but declined in dams with chronic hyperinsulinemia, suggesting a role of corin/PCSK6 pathway in the prevention of pregnancy-induced hypertension and intrauterine growth restriction, in this setting.

Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: a pooled analysis of 1018 population-based measurement studies with 88.6 million participants

BACKGROUND

Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure.

METHODS

We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probit-transformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure.

RESULTS

In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the high-income Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association.

CONCLUSIONS

Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups.

Is prolonged immobilization a risk factor for symptomatic venous thromboembolism in elderly bedridden patients?

Prolonged immobilization and advanced age are considered to be important risk factors for venous thromboembolism (VTE). Nevertheless, the need for VTE prophylaxis in long-term bedridden patients is not known. To assess whether very prolonged immobilization (i.e. over three months) carries an increased risk for clinically apparent VTE, we performed a historical-cohort study of nursing home residents during a ten-year period. Data concerning patient’s mobility and incidence of overt deep vein thrombosis or pulmonary embolism were registered. The mean resident age was 85 ± 8.4 years. Eighteen mobile and eight immobile patients were diagnosed with clinically significant thromboembolic events, during 1137 and 573 patient-years of follow up, respectively. The incidence of venous thromboembolic events was similar in both chronically immobilized and mobile patient groups, 13.9 and 15.8 per thousand patient years, respectively (p = 0.77). The rate ratio for having a VTE event in the immobilized patient group as compared with the mobile group was 0.88 (95% Confidence Interval (CI) 0.33 to 2.13). When taking into account baseline characteristics, risk factors and death rates by various causes, no differences were found between the two groups. In conclusion, chronically immobile bedridden patients are no more prone to clinically overt venous thromboembolic events than institutionalized mobile patients. Until further studies are performed concerning the impact of very prolonged immobilization on the risk of VTE, there is no evidence to support primary prevention after the first three months of immobilization. Evidence for efficacy or cost effectiveness beyond this early period is not available.

Association of Blood Pressure Variability Ratio With Glomerular Filtration Rate Independent of Blood Pressure and Pulse Wave Velocity

BACKGROUND

Blood pressure variability ratio (BPVR)(derived from within-subject SD of 24-hour ambulatory blood pressure [BP]) predicts all-cause mortality independent of BP and has a similar prognostic ability to ambulatory arterial stiffness (AASI). Whether BPVR, and AASI, offer prognostic information beyond measurements of arterial stiffness at a given pressure, as indexed by pulse wave velocity (PWV), is not known.

METHODS

We assessed whether BPVR and AASI were associated with indices of subclinical organ damage (TOD) [estimated glomerular filtration rate (eGFR), left ventricular mass index, early-to-late transmitral velocity (E/A), carotid intima-media thickness (IMT)] independent of BP, and whether BPVR-TOD and AASI-TOD relations were independent of PWV (applanation tonometry) in 772 randomly selected participants from an urban, developing community. AASI was derived from 24-hour diastolic BP vs. systolic BP standard linear regression.

RESULTS

On bivariate analyses, BPVR, AASI, and PWV were correlated with all indices of TOD (P < 0.0005). However, after adjustments for potential confounders including age and 24-hour mean BP, BPVR, and PWV (P < 0.005 to P < 0.0001), but not AASI (P > 0.25), were independently associated with eGFR, but not other indices of TOD. Importantly, the BPVR-eGFR relation was independent of BP variability (P < 0.005) and PWV (P < 0.001).

CONCLUSIONS

BPVR was negatively associated with eGFR independent of mean BP, BP variability, and PWV. Therefore, in the prediction of cardiovascular risk, measurements of arterial stiffening (BPVR) may provide information beyond the impact of arterial stiffness.

Supplementation with n-3, n-6, n-9 fatty acids in an insulin-resistance animal model: does it improve VLDL quality?

Could supplementation with n-3, n-6 and n-9 fatty acids prevent atherogenic alterations of VLDL produced in insulin-resistance?

Vasoactivity of the rat endovascular trophoblast

INTRODUCTION

Rat endovascular trophoblasts (EVasT) express smooth muscle (SM) proteins and contract ex vivo upon exposure to endothelin-1 (ET1) via receptors A and B (ETA, ETB). Presently, we investigated the EVasT response to NOS inhibition (N-Nitro-l-arginine methyl ester hydrochloride, l-NAME), and potentiation by NO donor [S-Nitroso-N-Acetyl-D,l-Penicillamine (SNAP)] following KCl precontraction. M&M: Luminal surface area (LSA) of remodeled spiral artery rings (SAR) devoid of SM was measured ex vivo upon exposure to l-NAME alone; l-NAME and ET1 representing the combined contractile effect of both ET1 receptors; l-NAME with ET1 and ETA antagonist, representing the isolated contractile effect via ETB. In another experiment we administered SNAP to KCl precontracted SAR. Statistical analysis was performed using 2-way mixed ANOVA and repeated measures.

RESULTS

l-NAME reduced LSA by 2.22%, 95% CI [0.83%, 3.60%] compared with control. ET1 and l-NAME reduced LSA immediately, compared with a plateau at 60min by ET1 alone. The isolated ET1 constrictive effect via ETB, reduced LSA by 5.94%; 95% CI [3.47%, 8.41%], significantly more than that obtained via ETA following 36 min of the experiment by 0.88%; 95%CI [0.09%, 1.67%]. Addition of KCl reduced LSA by 11.9%, 95% CI [9.6%, 14.1%]. Addition of SNAP increased LSA by 3.0%, 95% CI [1.7%, 4.3%].

CONCLUSIONS

EVasT of the rat remodeled spiral artery react to ET1 and KCl similar to vascular SM: contract via both ET1 receptors and KCl and relax by ET1 via ET_B and by SNAP. This phenomenon may play a role in rat models of gestational vasoactive systems dysregulation.

Aortic Pulse Pressure Amplification Imputed From Simple Clinical Measures Adds to the Ability of Brachial Pressure to Predict Survival

BACKGROUND

Although aortic-to-brachial pulse pressure amplification (PPamp) may offer prognostic information beyond brachial blood pressure (BP), this approach is limited in resource-limited settings. We aimed to derive an equation to impute central aortic PP (PPc) from simple clinical measures and assess whether imputed PPamp adds to the ability of brachial BP to predict mortality.

METHODS

An imputation equation for PPc, incorporating brachial PP, age, mean arterial pressure, and pulse rate, was identified from multivariate modeling of the factors associated with radial applanation tonometry-derived (measured) PPc in 1,179 community participants and validated in a clinical sample of 351 patients. We applied the equation to ambulatory awake BP and pulse rate values in a separate group of 4,796 patients referred for ambulatory monitoring and evaluated the impact on all-cause mortality.

RESULTS

Imputed PPc values closely approximated measured PPc (r (2) = 0.96, mean difference ± (2 × SD) = 1.4±6.2mm Hg). In adjusted Cox proportional models including adjustments for awake brachial PP during 47,111 person-years of follow-up, where 648 patients died, hazards ratio for all-cause mortality per SD of awake PPamp was 0.79 (95% confidence interval (CI): 0.68-0.93, P < 0.005). The hazards ratio for brachial PP with (1.49, CI = 1.36-1.64, P < 0.0001) or without (1.46, CI = 1.35-1.59, P < 0.0001) PPamp in the model was similar. Awake PPamp also predicted survival independent of awake brachial systolic BP (P < 0.0001).

CONCLUSIONS

PPc imputed from simple clinical assessments closely approximates measured PPc. PPamp derived from imputed PPc adds to the ability of brachial BP to predict survival. In resource-limited settings, an imputation equation may be employed to approximate aortic BP and enhance risk prediction.

Left Ventricular Mass as a Risk Factor in the Oldest Old

In middle-aged and "young elderly" cohorts, higher left ventricular mass (LVM) is associated with worse outcomes. The authors examined LVM and 5-year mortality among community-dwelling 85-year-old patients. A representative sample (n=526, born 1920-1921) from the Jerusalem Longitudinal Cohort Study underwent echocardiography at age 85. LVM was indexed by body surface area (LVM-BSA) or height (LVM-Ht). Patients with higher LVM were less educated and sedentary and had poorer self-rated health, functional limitations, and increased comorbidity. Five-year mortality was 21.7% (n=114). Adjusted 5-year mortality rates were increased for the two upper quintiles of LVM-BSA (hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.05-3.06) and LVM-Ht (HR, 2.2; 95% CI, 1.2-3.5). A step up in mortality occurred around the third quintile corresponding with LVM-BSA 110 g/m(2) or LVM-Ht 51 g/m(2.7). Among the oldest old, elevated LVM is significantly associated with mortality.

Abstract P177: The Myotrophoblast of the Rat Placenta Ex Vivo Study of Nitric Oxide Synthase Inhibition

In pregnancy spiral arteries, are invaded by endovascular trophoblasts (EVT) and remodeled. Previously, NOS, and of smooth muscle proteins expression in EVT, and endothelin-1 (ET1) ex-vivo contraction of the remodeled artery were demonstrated, mediated by ET1 receptors A and B (ETA, ETB)

Placentas on gestational day 21, were dissected, spiral artery rings devoid of smooth muscle were fixed to a silicon-coated 8-well chamber slide in oxygenated solution.

Rings cut surface area (CSA) was observed under laser scanning confocal microscope. Following baseline, L-NAME and 10- 5 M, ET-1 10-7 M were added to some chambers. In other wells, also with ETA antagonist at 10-6 M (BQ-123).

CSA was measured using ImageJ software.

L-NAME alone, reduced CSA by 2.5% p=0.002. Addition of ET-1 to L-NAME, reduced CSA area immediately, compared with a plateau at 60min by ET1 p=0.001 .L-NAME, followed by ET-1 and ETA antagonist, the isolated constrictive effect of ET-1 via ETB, 7.2%, was earlier and stronger n than via ETA, 6.1% p< 0.001 (figure).

L-NAME + ET-1 causes contraction of the arterial ring via ETA and ETB, without the dilatory effect of NO.

ET-1 alone shows an earlier, immediate CSA reduction, compared to that of ET-1 without L-NAME, achieved at 40-60 minutes. This is in accordance with the instantaneous NO effect through ETB, compared with the gradual ET-1 induced CSA reduction .To isolate the contracting effect via ETB, we added L-NAME + ETA+ ET-1. The ETB contraction is earlier and stronger than that via ETA.

Thus, EVT of the rat remodeled spiral artery react to ET-1 like vascular smooth muscle of non-modified arteries: contraction via receptors A and B and relaxation via receptor B through NOS.