Systolic Blood Pressure In Females Research Articles

Abstract 13490: Sex Differences in the Association of Multi-Ethnic Genome-Wide Blood Pressure Polygenic Risk Score With Population Systolic Blood Pressure Trajectories

Introduction: Sex differences in the systolic blood pressure (SBP) trajectories have been described previously. However, the contribution of underlying genetic architecture to the sex associated differences in SBP trajectories has not been assessed. Methods: Multiancestry sex-specific SBP polygenic risk scores (SBP-PRS), accumulating 1.1 million variants each, were calculated in the participants of the ARIC, JHS, CARDIA, CHS, MESA, FHS, and JHS who underwent whole genome sequencing under the TransOmics for Precision Medicine Program. Based on the SBP-PRS, the cohort was stratified into low (<20 th centile), intermediate (20 th -80 th centile), and high (>80 th centile) genetic risk of SBP. For individuals on antihypertensive medications, SBP measurements were corrected by adding 15 mmHg. Multivariable adjusted restricted cubic splines were used to depict the non-linear relationship of SBP with age in each sex separately. Bootstrapping using 1000 samples was used to estimate the age and 95% CIs at which the sex-specific SBP trajectories crossed over in each SBP-PRS group. Results: In this study of 21,542 individuals (median age: 56 years; 56.0% females; 35.8% non-White individuals), the non-linear association of SBP with age varied by sex (P interaction : <0.001) and SBP-PRS groups (P interaction : 0.05). On stratifying by SBP-PRS, females had a higher age-related increase in SBP compared with males across the groups (p<0.001 in low, intermediate, and high SBP-PRS groups). The age at which the SBP in females surpassed that of males progressively decreased with increasing genetic risk of SBP [low: 66.7 (66.4-67.0) years, intermediate: 64.3 (64.1-64.6) years, high: 55.8 (54.4-57.1) years; p: <0.001]. In the high SBP-PRS group, the sex-associated differences in SBP trajectories were modest with females and males having nearly similar SBP values in old age. Conclusion: The underlying genetic architecture may contribute to sex difference of SBP trajectories.

Differential influences of serum vitamin C on blood pressure based on age and sex in normotensive individuals.

Hypertension is among the most prevalent chronic diseases with diverse etiology, affecting over 1 billion people globally. In numerous studies, vitamin C inversely correlated with blood pressure and was suspected to have antihypertensive properties. Currently, there is conflicting evidence regarding the relationship between vitamin C and blood pressure, with most studies being conducted on hypertensive subjects. The principal objective of this project was to investigate the relationship between vitamin C and blood pressure in normotensive adult subjects. A total of 2,533 individuals aged 20 years and above were enrolled in the present study from the National Health and Nutrition Examination Survey (NHANES) 2017-2018. Outcome variables were systolic blood pressure (SBP) and diastolic blood pressure (DBP). Serum vitamin C was regarded as an independent variable. EmpowerStats software and R (version 3.4.3) were used to examine the association between vitamin C and SBP or DBP. Vitamin C was reversely correlated with both SBP (β = -0.02, 95% CI: -0.03 to -0.00, p = 0.0306) and DBP (β = -0.02, 95% CI: -0.04 to -0.01, p = <0.0011) after adjusting all covariates. This reverse relationship may be affected by a number of factors, including a person's gender, age, race, and ethnicity. A U-shaped association between vitamin C and SBP in females and an inverted one between vitamin C and DBP in males were detected, respectively. We further calculated the inflection points at 90.3 μmol/L for females and 40 μmol/L for males. It is somewhat surprising that a reverse U-shaped distribution between vitamin C and SBP and DBP in people over 50 was detected, and the point of inflection of vitamin C were all located at 40 μmol/L. Vitamin C was negatively correlated with both SBP and DBP in this cross-sectional analysis. However, a U-shaped relationship and an inverted one were also observed in certain people, which implied that, though vitamin C is considered a vital antioxidant, maintaining vitamin C at appropriate levels may be beneficial according to different populations.

Uric acid and blood pressure in NHANES dated from 2009 to 2018: A cross-sectional research

Background and aimThis study aimed to explore the association between uric acid (UA) and blood pressure (BP), included systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP). Methods and resultsA cross-sectional study with 22,478 individuals aged from 12 to 80 years (11,443 males and 11,035 females) from the National Health and Nutrition Examination Survey (NHANES) was performed. Multiple linear regression analysis was applied to explore the relationship between UA and BP, Stratified analysis and interaction were performed based on gender, race, age, body mass index (BMI), and alcohol consumption. Significantly positively associations were presented in SBP(β, 0.84 [95% CI, 0.67, 1.00]), DBP(β, 0.23 [95% CI, 0.11, 0.36]), and MAP (β, 0.43 [95% CI, 0.31, 0.55]). The associations were much more stronger between UA and SBP in females (β, 1.04 [95% CI, 0.78, 1.30], p for interaction 0.0003), black group (β, 1.17 [95% CI, 0.77, 1.56], p for interaction 0.0296), age (≥45) group (β, 1.03 [95% CI, 0.68, 1.39], p for interaction <0.0001) and drinking group (β, 0.98 [95% CI, 0.75, 1.21], p for interaction <0.0001). The significant interactions were found between UA and DBP in gender and alcohol consumption (all p for interaction <0.05). In terms of MAP, the significant interactions were found in race, age, and alcohol consumption (all p for interaction <0.05). ConclusionsA significantly positively association was found between UA and BP, including SBP, DBP, and MAP.

Sex differences in predictors and regional patterns of brain age gap estimates.

The brain‐age‐gap estimate (brainAGE) quantifies the difference between chronological age and age predicted by applying machine‐learning models to neuroimaging data and is considered a biomarker of brain health. Understanding sex differences in brainAGE is a significant step toward precision medicine. Global and local brainAGE (G‐brainAGE and L‐brainAGE, respectively) were computed by applying machine learning algorithms to brain structural magnetic resonance imaging data from 1113 healthy young adults (54.45% females; age range: 22–37 years) participating in the Human Connectome Project. Sex differences were determined in G‐brainAGE and L‐brainAGE. Random forest regression was used to determine sex‐specific associations between G‐brainAGE and non‐imaging measures pertaining to sociodemographic characteristics and mental, physical, and cognitive functions. L‐brainAGE showed sex‐specific differences; in females, compared to males, L‐brainAGE was higher in the cerebellum and brainstem and lower in the prefrontal cortex and insula. Although sex differences in G‐brainAGE were minimal, associations between G‐brainAGE and non‐imaging measures differed between sexes with the exception of poor sleep quality, which was common to both. While univariate relationships were small, the most important predictor of higher G‐brainAGE was self‐identification as non‐white in males and systolic blood pressure in females. The results demonstrate the value of applying sex‐specific analyses and machine learning methods to advance our understanding of sex‐related differences in factors that influence the rate of brain aging and provide a foundation for targeted interventions.

Weakened Grip Strength Over 40 Years in a Community-Dwelling Cohort in Tanushimaru, Japan.

An epidemiological survey has been periodically performed since 1977 among the adult population in Tanushimaru, a typical farming town in Japan. We aimed in this study to retrospectively investigate changes of grip strength (GS) and its correlates over 40 years in the same cohort of community-dwelling adults. We used pooled data from the survey to deduce essential correlates of GS in community-dwelling adults. We retrospectively compared serial correlates of GS in the adult population in Tanushimaru between a population tested in 1977 and 1979 (Cohort A, n=2,452) and another population tested in 2016 and 2018 (Cohort B, n=1,505), to identify essential correlates of GS for investigating changes in GS during the past 40 years in community-dwelling adults. Age, height, weight, and the occupation of the subjects remained as correlates of GS in both genders during the past 40 years. In males, abdominal circumference also remained as a correlate of GS. Serum albumin levels in males and systolic blood pressure in females were identified as new correlates. GS after adjustment for the above correlates weakened in both genders, and the serial change in GS was particularly remarkable in subjects whose occupations were Class-1 and Class-2, which were defined as moderately hard work. From a periodically-performed epidemiological survey of a community-dwelling cohort in a Japanese typical farming town, age, height, weight, and occupation were deduced as essential correlates of GS. GS in the community dwelling cohort weakened in both genders over 40 years, possibly affected by their occupation.

The Prevalence of Insulin Resistance and the Associated Risk Factors in a Sample of 14-18-Year-Old Slovak Adolescents.

The prevalence of cardiometabolic risk factors has increased in Slovakian adolescents as a result of serious lifestyle changes. This cross-sectional study aimed to assess the prevalence of insulin resistance (IR) and the associations with cardiometabolic and selected lifestyle risk factors in a sample of Slovak adolescents. In total, 2629 adolescents (45.8% males) aged between 14 and 18 years were examined in the study. Anthropometric parameters, blood pressure (BP), and resting heart rate were measured; fasting venous blood samples were analyzed; and homeostasis model assessment (HOMA)-insulin resistance (IR) was calculated. For statistical data processing, the methods of descriptive and analytical statistics for normal and skewed distribution of variables were used. The mean HOMA-IR was 2.45 ± 1.91, without a significant sex differences. IR (cut-off point for HOMA-IR = 3.16) was detected in 18.6% of adolescents (19.8% males, 17.6% females). IR was strongly associated with overweight/obesity (especially central) and with almost all monitored cardiometabolic factors, except for total cholesterol (TC) and systolic BP in females. The multivariate model selected variables such as low level of physical fitness, insufficient physical activity, breakfast skipping, a small number of daily meals, frequent consumption of sweetened beverages, and low educational level of fathers as significant risk factors of IR in adolescents. Recognizing the main lifestyle risk factors and early IR identification is important in terms of the performance of preventive strategies. Weight reduction, regular physical activity, and healthy eating habits can improve insulin sensitivity and decrease the incidence of metabolic syndrome, type 2 diabetes, and cardiovascular disease (CVD).

Relationship of neck circumference to some cardiometabolic risk parameters

Background Neck circumference (NC) is an easy and reliable anthropometric measurement. The use of NC as an indicator of obesity among Egyptians was previously established. However, the relationship between NC and different cardiometabolic risk (CMR) parameters was not previously studied in the Egyptian population. Objective The aim of this work was to study the relationship between NC and some CMR parameters in obese adult Egyptian individuals. Participants and methods This cross-sectional study was carried out on 100 apparently healthy obese adult Egyptian participants (BMI ≥30 kg/m2), above the age of 18 years, 50% of them were males and the other 50% were females. NC and other traditional anthropometric measurements were evaluated. Blood samples were assayed for glycosylated hemoglobin, total cholesterol, high-density lipoprotein cholesterol (HDL-C), non-HDL-C, and high-sensitivity C-reactive protein. Results There were significant positive correlations between NC and each of systolic and diastolic blood pressure [(r=0.527, P&lt;0.001), (r=0.430, P&lt;0.001), respectively], waist circumference (r=0.538, P&lt;0.001), BMI (r=0.403, P&lt;0.001), and high-sensitivity C-reactive protein (r=0.304, P=0.002). While a significant negative correlation was found between NC and HDL-C. Multivariate regression analysis revealed an independent association of NC with waist circumference in males and with systolic blood pressure in females. Conclusion This study does not only confirm the association of NC with anthropometric measurements in the Egyptian population, but it also establishes the NC association with CMR factors that support the possibility of using NC as a CMR marker among Egyptians.

Correlation of body mass index with blood pressure: A gender based comparison in medical students.

The Obesity and Hypertension are major risk factors of several life threatening diseases in human body. Objectives: To determine correlation coefficient of Body Mass Index with blood pressure: a gender based comparison in medical students. Study Design: Comparative Cross-sectional study in students. Setting: Physiology department of BMU Karachi. Period: Duration of this study was 6 months from February 2017 to August 2017. Material and Methods: A total of 500 students were enrolled in this study. The anthropometric measurement [height (m2) and weight (kg)] was recorded for calculation of the Body Mass Index (BMI) and blood pressure (BP) was measured by using sphygmomanometer with stethoscope. SPSS version 22.0 was used to analyze the data. Results: BMI overall in both genders were significantly (p&lt;0.05) correlated in mean Systolic Blood Pressure (SBP) and mean Diastolic Blood Pressure (DBP). Underweight and Normal weight were not correlated with both mean SBP and mean DBP in both genders. Overweight subjects were positively correlated with mean DBP in males and mean SBP in females (p&lt;0.05). Obese students were not significantly (p&gt;0.05) correlated with both mean SBP and mean DBP in males whereas, there were not enough observations to draw any meaningful conclusion in females. Conclusion: Overweight subjects were positively correlated (p&lt;0.05) with mean DBP in males and mean SBP in females and overall BMI (mean SBP &amp; mean DBP) in both genders.

Blood Viscosity, Glycemic Markers and Blood Pressure: A Study in Middle-Aged Normotensive and Hypertensive Type 2 Diabetics.

Altered blood viscosity (BV) may affect blood pressure (BP) and develops further complications in diabetes. A case-control study was performed to examine the relationship of erythrocyte sedimentation rate (ESR), hematocrit, fibrinogen, and BV with glycemic markers and BP in middle-aged normotensive and hypertensive type 2 diabetic patients and healthy controls. A total of 145 participants between age group 30-50years divided into three groups; controls (n = 60), type 2 diabetes mellitus (T2DM, n = 55), and T2DM with hypertension (T2DM + HTN, n = 30). ESR and hematocrit were determined by Wintrobe's method. Plasma fibrinogen was measured using Lempert method and BV calculated using Merill's formula. T2DM and T2DM + HTN patients had higher fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), ESR, and fibrinogencompared to controls. In both male and female SBP, DBP, MAP, FPG, and HbA1c were significantly higher in T2DM and T2DM + HTN groups, compared to controls. Further, linear regression analysis revealed a positive association of ESR and fibrinogen with SBP, DBP, MAP, FPG, HbA1c, and positive diabetic status in all participants. Also, in the same analysis, BV showed a positive association with SBP, DBP, and MAP. The association of ESR and fibrinogenwith glycemic markers and BP in diabetes supporting the value of emerging marker's for early prediction of T2DM and hypertension.

Trends in Blood Pressure and Prevalence of Hypertension in Korean Adults Based on the 1998-2014 KNHANES.

PurposeTo investigate trends in blood pressure (BP) and hypertension prevalence in Korea.Materials and MethodsBased on the Korean National Health and Nutrition Examination Survey (KNHANES) I (1998), II (2001), III (2005), IV (2007–2009), V (2010–2012), and VI (2013–2014), 56077 participants (23974 men and 32103 women) were included.ResultsMean systolic BP (SBP) and diastolic BP (DBP) decreased in both sexes (male SBP: 128.1 to 120.2 mm Hg, male DBP: 82.0 to 78.5 mm Hg; female SBP: 125.7 to 116.0 mm Hg and female DBP: 77.4 to 73.2 mm Hg from the KNHANES I–VI). The age-standardized prevalence of hypertension was significantly decreased in both sexes (male; 33.3% to 30.3%, female; 28.7% to 22.7%, all p for trend <0.001). Regardless of taking anti-hypertensive medication or not, SBP and DBP declined universally in both sexes. Compared to the KNHANES I, the odds ratios (95% confidence intervals) of the KNHANES II to VI for less-than-normotensive and less-than-hypertensive BP increased in both sexes.ConclusionMean BP levels in both sexes and hypertension prevalence showed downward trends during the 16-year period.

Impact of coronary artery disease on augmentation index as measured by estimated central blood pressure: A case control study in Asian Indians

AimsWe compared various components of blood pressure and arterial stiffness of healthy control with those of coronary artery disease (CAD) patients using BP+ machine™. MethodsIn this prospective, case-control study, total 585 individuals of both the genders were enrolled. The study population consisted of 277 controls (healthy siblings of diseased subjects not having CAD – group A) and 308 CAD patients (group B). Age and sex adjusted regression and receiver operative curve (ROC) analysis was performed to assess the strength of association of these parameters. ResultsWe found that mean systolic blood pressure (SBP) (137.14±22.49 vs. 129.26±19.86), central systolic blood pressure (CSBP) (130.78±21.89 vs. 117.53±17.98), augmentation index (AI) (108.55±44.98 vs. 49.38±21.03) and pulse rate variability (98.82±231.09 vs. 82.86±208.77) were significantly (p<0.05) higher in CAD population as compared to healthy counterparts. Left ventricular contractibility as measured by dP/dt was significantly lower in CAD patients. All these parameters were significantly abnormal in CAD as compared to healthy control population irrespective of the gender of the patient except for SBP in females. Both – odds ratio (1.108; 95% CI: 1.081–1.135; p<0.0001) and ROC analysis (AUC: 0.937; 95% CI: 0.919–0.956; p<0.0001) showed AI as the strongest predictor of CAD, closely followed by CSBP. ConclusionCentral aortic blood pressure parameters such as AI and CSBP measured noninvasively with BP+ machine could be the effective predictors of CAD in Asian Indians.

Abstract P190: Long-term Intake of Muscadine Grape Extract Markedly Improves Exercise Capacity in Older Female (mRen2)27 Hypertensive Rats

Muscadine grapes ( Vitis rotundifolia ) contain significant levels of polyphenols and their antioxidant capacity may have cardiovascular benefit. We determined the cardiovascular effects of a water soluble muscadine grape extract (MGE) from Piedmont Research &amp; Development Corporation (PRDC, Winston-Salem, NC) that we confirmed has a high content of epicatechin, gallic acid, ellagic acid and procyanidin B2. We hypothesize that this soluble MGE with a potentially high phenolic bioavailability exhibits cardioprotective actions. The effect of long-term MGE intake on blood pressure, cardiac function and exercise tolerance was established in female and male hemizygous (mRen2)27 [mRen2] transgenic rats, an Ang II-AT 1 R-dependent model of hypertension. The mRen2 were administered MGE (8 mg of total phenolics/mL) in the drinking water for 26 weeks (7 female; 7 male); control rats (9 female; 11 male) were given water only. At 40 weeks of age, exercise tolerance was assessed by treadmill (10.2 m x min -1 , 5% inclination). The MGE-treated female mRen2 exhibited a &gt;300% improvement in workload ( W: g X m ) as compared to the untreated group [14551 ± 1313 vs. 4498 ± 481; p&lt;0.01]. MGE intake also extended the time to fatigue (TTF) by 300% in females (4943 ± 443 vs.1615 ± 166 sec; p&lt;0.01). In contrast, chronic intake of MGE had no effect on either exercise workload or TTF in the male mRen2. MGE intake did not alter systolic blood pressure in females (162 ± 3 vs. 166 ± 6 mm Hg, p&gt;0.05) and males (165 ± 5 vs. 160 ± 3 mm Hg) nor alter body weight in either group [females: 334 ± 7 g vs. 339 ± 8 g; males: 613 ± 12 g vs. 590 ± 6 g). Echocardiographic analyses revealed that although the female mRen2 exhibited a higher ejection fraction [73.4±5.1 vs. 42.3±4.5%, n=4-5, p&lt;0.05] and a higher fractional shortening [44.2±4.2 vs. 22.1±2.7%, n=4-5, p&lt;0.05] as compared to males, MGE treatment did not improve these indices in either group. We conclude that the marked improvement in exercise capacity in older adult hypertensive females by chronic MGE intake is not accompanied by augmented cardiac performance, perhaps reflecting the lack of an effect on blood pressure. Thus, it is possible that MGE may directly impact the skeletal muscle to improve exercise in the hypertensive mRen2 females, but not the males.

Gender Variations in Wellbeing Indicators between Urban and Mountain Landscape Environments

&lt;p class="1Body"&gt;The issue of variations in physiological indicators of wellbeing based on gender serves as incentive for natural landscape environment interactions. This study examined gender variations in blood pressure, pulse rate and respiratory rate between contact with low-altitude urban (pretest) and mountain landscape environments (posttest). To attain the goal of this study, 38 respondents (16 males, 22 females) participated in the seven-day experimental study. Pretest and posttest measures of blood pressure, pulse rate and respiratory rate were elicited from both male and female respondents at the urban environment within the first three days and at the mountain landscape environment the following three days. Results show that both male and female systolic blood pressure increased at the mountain landscape environment while their diastolic blood pressure reduced marginally. There was no difference in gender response in terms of pulse rate. Conversely, male respondents experienced reduction of respiratory rate at the mountain landscape environment while female respondents experienced increase. Findings suggest that the only apparent difference in gender response is in their respiratory rate. The extent to which gender might be related to physiological wellbeing through contact with natural mountain landscape environment is revealed. Hence, a platform is set for policy makers and governments for the creative harnessing of mountain landscape environments.&lt;/p&gt;

Mediating effect of blood lipids on correlation between body fat and blood pressure among overweight adults

To understand the mediating effect of blood lipids on the correlation between body fat and blood pressure among overweight adults. Overweight and obese subjects aged 20-55 years who had lived in Beijing for at least 1 year were recruited in this study, Body mass index (BMI) was used as a screening indicators. The percentage of body fat (PBF) was measured for the subjects by using dual energy X-ray absorptiometry (DXA). Mediating effect analysis was conducted to analyze the mediating effect of blood lipids on correlation between PBF and systolic blood pressure (SBP) as well as diastolic blood pressure (DBP). After adjusting for age, PBF was positively correlated with SBP and DBP in both males (β = 0.208 3, β = 0.205 2, P < 0.001) and females (β = 0.188 4, β = 0.209 6, P < 0.001). In male subgroup, PBF was negatively correlated with HDL-C level, but positively correlated with LDL-C level (β = -0.142 2, P < 0.01 and β = 0.180 5, P < 0.001), while in female subgroup, PBF was positively correlated with both TC level and LDL-C level (β = 0.172 1, P < 0.001 and β = 0.233 5, P < 0.001). With PBF controlled, TC and TG levels were positively correlated with DBP in both males and females (β = 0.095 6, 0.090 5 for males, β = 0.117 6, 0.083 1 for females, P < 0.05), and TG level was positively correlated with SBP in females (β = 0.127 2, P < 0.001). Further analysis indicated there was a significant mediating effect of LDL-C on correlation between PBF and DBP in females, with the mediating effect value of 0.019 4 (P < 0.05). The ratio of mediating effect was 9.26%. PBF was positively correlated with blood pressure, but blood lipids had no mediating effect on the correlation between PBF and blood pressure in males, while LDL-C level had mediating effect on PBF and blood pressure in females.

Blood Pressure Profile in School Children (6–16 Years) of Southern India: A Prospective Observational Study

Aims and objective: To determine normal blood pressure (BP) in apparently healthy, asymptomatic school children in the age group of 6–16 years and to determine the correlation of BP values with different sex, weight, height, and body mass index (BMI) and also to find out prevalence of hypertension in school going population.Materials and methods: This prospective, observational study enrolled 3,302 urban children (1,658 boys and 1,644 girls) in the age group of 6–16 years. These were analyzed to study the distribution pattern of systolic blood pressure (SBP) and diastolic blood pressure (DBP) at different ages, sex, weight, height, and BMI. The SBP and DBP were noted as per age and sex. The association was seen between mean SBP and mean DBP with weight, height, and BMI. Information was collected about the family history of hypertension and was correlated with the obtained SBP and DBP readings.Results: The mean SBP in males at 6 years was 99.69 ± 3.62 mm of Hg, at 10 years was 102.20 ± 2.16 mm of Hg, and at 16 years was 115.33 ± 1.26 mm of Hg. The mean SBP in females at 6 years was 96.55 ± 2.86 mm of Hg, at 10 years was 101.16 ± 2.12 mm of Hg, and at 16 years was 112.41 ± 1.06 mm of Hg. The correlation coefficient for relationship between age and SBP in males and females was 0.89 and 0.91, respectively, and for DBP was 0.92 and 0.90, respectively. The correlation coefficient for relationship between height and SBP in males and females was 0.91 and 0.93, respectively, and for DBP was 0.92 and 0.88, respectively. The correlation coefficient for relationship between weight and SBP in males and females was 0.92 and 0.92, respectively, and for DBP was 0.94 and 0.91, respectively. In the nomogram obtained in the study, 95% of study population fall between mean +2SD and −2SD.Conclusion: The blood pressure (BP) (SBP and DBP) tends to increase with age, weight, height, and BMI. The BP values (SBP and DBP) increases grossly after 11 years of age. The students with positive family history of hypertension had higher valve when compared to other student. The BP of children and adolescents can be evaluated using the reference table according to age. The table provided helps to classify as “normal” or “hypertension” (>+2SD).

Angiotensin-converting enzyme 2 activity in patients with chronic kidney disease

BackgroundAngiotensin-converting enzyme 2 (ACE2) is a novel regulator of the renin–angiotensin system that counteracts the adverse effects of angiotensin II. In heart failure patients, elevated plasma ACE2 activity predicted adverse events and greater myocardial dysfunction. We aimed to describe plasma ACE2 activity and its clinical associations in patients with kidney disease.MethodsPatients recruited from a single centre comprised of chronic kidney disease Stage III/IV (CKD), haemodialysis patients and kidney transplant recipients (KTRs). Plasma ACE2 enzyme activity was measured using a fluorescent substrate assay in plasma, collected at baseline and stored at −80°C. Linear regression was performed in both males and females separately to determine the covariates associated with log-transformed ACE2.ResultsThe median (interquartile range) plasma ACE2 activity in pmol/mL/min was 15.9 (8.4–26.1) in CKD (n = 59), 9.2 (3.9–18.2) in haemodialysis (n = 100) and 13.1 (5.7–21.9) in KTR (n = 80; P < 0.01). In male haemodialysis patients, ACE2 activity was 12.1 (6.8–19.6) compared with 4.4 (2.5–10.3) in females (P < 0.01). Log-transformed ACE2 plasma activity was associated with post-haemodialysis systolic blood pressure in females [β-coefficient 0.04, 95% confidence interval (95% CI) 0.01–0.06, P = 0.006]. In males, log-transformed ACE2 plasma activity was associated with B-type natriuretic peptide (β-coefficient 0.39, 95% CI 0.19–0.60, P < 0.001). Plasma ACE2 activity was not associated with mortality.ConclusionsPlasma ACE2 activity is reduced in haemodialysis patients compared with CKD patients, and in female haemodialysis patients compared with male. The different associations of plasma ACE2 activity between male and female haemodialysis patients indicate that the role of ACE2 in cardiovascular disease may differ by gender.

Epidemiological Study of AGT Gene Polymorphism among Chinese Subjects with Primary Hypertension

Background: Polymorphisms in the promoter region of the angiotensinogen (AGT) gene may affect AGT transcription and thus blood pressure. We determined the frequency of the AGT A-20C polymorphism in Chinese patients with primary hypertension. Using a molecular epidemiology approach, we also determined the relationship between primary hypertension and environmental-AGT A-20C polymorphism interactions. Methods: 912 subjects diagnosed with primary hypertension were analyzed from Shenyang Chinese Populationsand their samples were genotyped using A-20C polymorphism within angiotensinogen (AGT) gene by o€€µestriction o€€©ragment o€€¯ength Polymorphism methods (PCR-RFLP) Results: PCR and restriction fragment length polymorphism techniques were used to determine the distribution frequency of AGT A-20C alleles. Frequencies of 84.7% and 15.3% were observed for the A and C alleles, respectively. The polymorphism was in Hardy-Weinberg equilibrium according to a χ2 test (χ2=0.58, P>0.05). Linear regression of AGT genotype and blood pressure revealed that systolic blood pressure was significantly higher for AC and CC genotypes compared to the wild-type AA genotype in females (P<0.05). Conclusion: This is the first report on the frequency of AGT A-20C polymorphism in a Chinese population. Compared to the AA genotype, the effects of genotypes AC and CC on blood pressure were mainly manifest as significantly higher systolic blood pressure in females.

Factors affecting the estimated maximal oxygen uptake: a follow-up study of participants in the total health promotion plan

To elucidate the effects of risk factors for arteriosclerosis on estimated VO(2) max and obtain useful information to advise enterprise employees. One hundred and nineteen male and 87 female enterprise employees underwent exercise tests for health evaluation in the Total Health Promotion Plan at the Fukui Occupational Health Center between April 1990 and March 1993. Multiple regression analysis was performed using estimated VO(2) max as the dependent variable, and percent body fat, blood pressure, blood tests, habitual physical activity, number of cigarettes smoked and alcohol consumption as independent variables in the first and second year, and for yearly changes in these variables. The significant variables selected were as follows: in the first year, systolic blood pressure and percent body fat in males, and age in females; in the second year, diastolic blood pressure and habitual physical activity in males and systolic blood pressure in females; for yearly changes in each variable, cigarettes in males and percent body fat in females were selected. It was suggested that guidance to reduce cigarettes in males, and to keep a proper percent body fat in females would be effective in maintaining the estimated VO(2) max.

Endothelin-A-receptor blockade improves renal function and doubles the lifespan of stroke-prone spontaneously hypertensive rats.

This study assessed whether the orally active endothelin-A- (ETA) receptor antagonist, BMS 182874 (BMS), affects systolic blood pressure (SBP), renal function and survival in salt-loaded stroke-prone spontaneously hypertensive rats (SHRSPs). Eight-week-old male and female SHRSPs were given a high-salt diet (4% NaCl) (n = 6/group). The treatment groups (n = 6/group), also on a high-salt diet, were administered BMS (40 mg/kg/day) which was mixed in the food. In untreated SHRSPs, mean survival was 136 days (range 96-194 days) in males, and 98 days (range 74-112 days) in females. Treatment with BMS increased survival to 223 days in males (range 129-280 days, p <0.01 vs controls) and 156 days (range 124-180, p < 0.05 vs controls) in females. SBP increased to approximately 240 mmHg in all groups. BMS had no effect on SBP in females and a small, but significant (p < 0.05), SBP-lowering effect in males. In control rats, severe renal disease was evident at 16 weeks (proteinuria, 161 +/- 1.3 mg/day). In the treated group, development of proteinuria was significantly delayed (13 +/- 0.5 mg/day at 16 weeks). In conclusion ETA-receptor antagonism prolongs survival and improves renal status, but has little effect on the progression of hypertension. These data suggest that interruption of the endothelin (ET) system by blockade of ETA-receptors may achieve protection from target-organ damage despite lack of a reduction in blood pressure.

Endothelin-A-Receptor Blockade Improves Renal Function and Doubles the Lifespan of Stroke-Prone Spontaneously Hypertensive Rats

Summary: This study assessed whether the orally active endothelin-A-(ETA) receptor antagonist, BMS 182874 (BMS), affects systolic blood pressure (SBP), renal function and survival in salt-loaded stroke-prone spontaneously hypertensive rats (SHRSPs). Eight-week-old male and female SHRSPs were given a high-salt diet (4% NaCl) (n = 6/group). The treatment groups (n = 6/group), also on a high-salt diet, were administered BMS (40 mg/kg/day) which was mixed in the food. In untreated SHRSPs, mean survival was 136 days (range 96-194 days) in males, and 98 days (range 74-112 days) in females. Treatment with BMS increased survival to 223 days in males (range 129-280 days, p < 0.01 vs controls) and 156 days (range 124-180, p < 0.05 vs controls) in females. SBP increased to ˜240 mmHg in all groups. BMS had no effect on SBP in females and a small, but significant (p < 0.05), SBP-lowering effect in males. In control rats, severe renal disease was evident at 16 weeks (proteinuria, 161 ± 1.3 mg/day). In the treated group, development of proteinuria was significantly delayed (13 ± 0.5 mg/day at 16 weeks). In conclusion ETA-receptor antagonism prolongs survival and improves renal status, but has little effect on the progression of hypertension. These data suggest that interruption of the endothelin (ET) system by blockade of ETA-receptors may achieve protection from target-organ damage despite lack of a reduction in blood pressure.