Determinants Of Blood Pressure Research Articles

Determinants of arterial stiffness and central blood pressure in the very elderly

Pulmonary arterial hypertension (PAH) is a severe and increasingly prevalent disease, manifested by the maladaptation of pulmonary vasculature, which consequently leads to right heart failure and possibly even death. The development of PAH is characterized by specific functional as well as structural changes, primarily associated with the aberrant function of the pulmonary artery endothelial cells, smooth muscle cells, and vascular fibroblasts. MicroRNAs constitute a class of small ≈22–nucleotides–long non–coding RNAs that post–transcriptionally regulate gene expression and that may lead to significant cell proteome changes. While the involvement of miRNAs in the development of various diseases—especially cancer—has been reported, numerous miRNAs have also been associated with PAH onset, progression, or treatment responsiveness. This review focuses on the role of microRNAs in the development of PAH as well as on their potential use as biomarkers and therapeutic tools in both experimental PAH models and in humans. Special attention is given to the roles of miR–21, miR–27a, the miR–17–92 cluster, miR–124, miR–138, the miR–143/145 cluster, miR–150, miR–190, miR–204, miR–206, miR–210, miR–328, and the miR–424/503 cluster, specifically with the objective of providing greater insight into the pervasive roles of miRNAs in the pathogenesis of this deadly condition.

Compromised Salt Dependence of ENaC Activity Upon Deletion of AT1 Receptors

ENaC-mediated sodium reabsorption in the collecting duct (CD) is an essential determinant of blood pressure in humans. Cumulative evidence suggests direct action of Angiotensin II (Ang II) on ENaC activity in the CD, independently of the classical aldosterone signaling. The significance of regulation by Ang II becomes particularly important during Ang II dependent hypertension, when overactive ENaC is poorly regulated via aldosterone – mineralocorticoid receptor (MR) axis. Stimulatory Ang II actions on ENaC are mediated by AT1 receptors (AT1R). AT1R knockouts have decreased blood pressure despite elevated aldosterone levels. This indicates that aldosterone-MR cascade alone cannot provide sufficient input to adequately regulate ENaC-dependent sodium re-uptake. Using freshly isolated split-opened CDs we found that genetic deletion of AT1R markedly diminishes ENaC activity on low and regular sodium intake, significantly blunting salt-dependent regulation of ENaC. The observed decrease of ENaC activity was mainly attributed to a reduced channel open probability (Po). Pharmacological inhibition of AT1R with losartan in wild-type animals reproduces the effect of genetic ablation of AT1R on ENaC activity. Interestingly, saturation of aldosterone signaling with DOCA has minimal stimulatory effect on ENaC upon AT1R deletion, which can be explained by a markedly diminished MR abundance in the CD cells of the knockouts. Overall, genetic ablation of AR1R elicits a complex inhibitory effect on ENaC activity, directly attenuating ENaC Po and precluding adequate compensation by aldosterone cascade due to decreased MR expression.

Mutation within the hinge region of the transcription factor Nr2f2 attenuates salt-sensitive hypertension.

Genome-wide association studies (GWAS) have prioritized a transcription factor, Nuclear Receptor 2 Family 2 (NR2F2), as being associated with essential hypertension in humans. Here we provide evidence that validates this association and indicates that Nr2f2 is a genetic determinant of blood pressure (BP). Using the zinc-finger nuclease technology, the generation of a targeted Nr2f2-edited rat model is reported. The resulting gene-edited rats have a 15bp deletion in exon 2 leading to a 5 amino acid deletion in the hinge region of the mutant Nr2f2 protein. Both systolic and diastolic blood pressures of the Nr2f2mutant rats are significantly lower than controls. Because the hinge region of Nr2f2 is required for interaction with Friend of Gata2 (Fog2), protein-protein interaction is examined. Interaction of Nr2f2mutant protein with Fog2 is greater than that with the wild type Nr2f2 indicating that the extent of interaction between these two transcription factors critically influences BP.

Nutritional Epidemiological Tools for Sodium Intake

Dietary sodium is a determinant of blood pressure. Modern diets provide excessive amounts of salt, and in developed and developing countries the intake of processed foods with high salt levels is increasing. In order to establish effective nutrition policy, it is necessary to know the quantity of consumed salt as well as identify the main dietary sources of salt. Different methods are currently in use for estimating dietary sodium intake. The use of 24-hour urinary collection to assess sodium intake is considered the most accurate method but involves considerable burden for participants. The use of the spot urine method has been proposed as an alternative however in not recommended without calibration methodology. Sodium estimates based on dietary surveys include several methods such the 24-hour dietary recall, the food frequency questionnaire, and the diet record, with often under-estimates intake due to under-reporting and difficulties quantifying sodium in concentration discretionary salt and recipes. Food compositions databases and nutritional softwares can be used to assess sodium consumption. More research is necessary to improve nutritional epidemiological tools for sodium intake

Assessment of insulin resistant and the related cardio-metabolic factors in overweight-obese women presented with missed abortion, Baghdad, Iraq

Aims: This study aimed to assess the status of insulin resistance (IR) in overweight-obese women presented with missed abortion and to look for the presence of other cardio-metabolic risk factors. Setting and Design: This observational study was carried at Al-Yarmouk Teaching Hospital in Baghdad, Iraq during the period from March 1, 2014, to January 31, 2015. Materials and Methods: A total number of 60 patients presented with missed miscarriage and managed with misoprostol and, dilatation and curettage (D and C) were enrolled in the study. The data of anthropometric and blood pressure were collected. Fasting serum lipid profile, serum glucose, and fasting insulin were determined. IR is assessed by using the homeostatic model assessment-IR (HOMA-IR). The patients were grouped according to the body mass index (BMI) into Group I (BMI <25 kg/m 2 ) and Group II (BMI ≥25 kg/m 2 ). Results: There is the nonsignificant difference between Group I and Group II in the characteristics and the clinical presentations of the patients. Significant high percent of the history of missed miscarriage observed in Group II compared with Group I (35.6% vs. 6.7%, respectively). Group II women significantly needed D and C intervention in addition to misoprostol therapy compared with Group I (75.6% vs. 13.3%) respectively. Although the blood pressure and lipid profile determinants are within normal levels, they significantly higher in Group II compared with Group I. Fasting serum insulin levels and HOMA-IR index are significantly higher in Group II (13.0 ± 0.5 μU/ml and 2.75 ± 0.5 μU/ml) than Group I (12.2 ± 0.3 μU/ml and 2.43 ± 0.11 μU/ml), respectively. Conclusion: Miscarriage overweight-obese women have significant IR as well as alteration in metabolic determinants. Misoprostol per se is not enough to produce spontaneous expulsion of the uterine content and surgical intervention is needed in these women.

Genome-wide identification of long noncoding RNAs in rat models of cardiovascular and renal disease.

Long noncoding RNAs (lncRNAs) are an emerging class of genomic regulatory molecules reported in various species. In the rat, which is one of the major mammalian model organisms, discovery of lncRNAs on a genome-wide scale is lagging. Renal lncRNA sequencing and lncRNA transcriptome analysis were conducted in 3 rat strains that are widely used in cardiovascular and renal research: the Dahl salt-sensitive rat, the spontaneously hypertensive rat, and the Dahl salt-resistant rat. Through the RNA sequencing approach, 3273 transcripts were identified as rat lncRNAs. A majority of lncRNAs were without predicted target genes. Differential expression of 273 and 749 lncRNAs was detected between Dahl salt-sensitive versus Dahl salt-resistant and Dahl salt-sensitive versus spontaneously hypertensive rat comparisons, respectively. To couple the observed differential expression of lncRNAs with the status of mRNAs, an mRNA transcriptome analysis was conducted. Several cis mRNA genes were coregulated with lncRNAs. Of these, the protein expression status of 4 target genes, Asb3, Chac2, Pex11b, and Sp5, were differentially expressed between the relevant strain comparisons, thereby suggesting that the differentially expressed lncRNAs associated with these genes are candidate genetic determinants of blood pressure. This study serves as a first-generation catalog of rat lncRNAs and illustrates the prioritization of lncRNAs as candidates for complex polygenic traits.

Impact of age and gender on the haemodynamic determinants of blood pressure across the adult age-span

s 127 BCL11B gene expression levels among those with different genotypes. In addition, rs1461587G>T and rs17773233G>T polymorphisms influence aortic stiffness measured ex vivo, confirming previous observations. Further functional studies are required to elucidate the role of this locus on aortic stiffness.

Association of dietary pattern and body weight with blood pressure in Jiangsu Province, China.

BackgroundTo identify risk factors, associations between dietary patterns, body mass index (BMI), and hypertension in a Chinese population.MethodsDietary intake was assessed in 2518 adults by a 3-day 24 h recall and a food frequency questionnaire. Salt and oil intake was assessed by weighing records. Four dietary patterns were identified using principal component analysis. Overweight and obesity was determined according to the Chinese cut-offs for BMI. High blood pressure was defined as systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg. Prevalence ratios (PR) were calculated using Poisson regression.ResultsOf the subjects, 26.7% had high blood pressure. Subjects with overweight and obesity were more likely to have high blood pressure than those with normal weight (PR, 95% CI: 1.60, 1.40-1.87; 2.45, 2.11-2.85, respectively). Subjects with a ‘traditional’ dietary pattern were more likely to have high blood pressure (P for trend = 0.001), whereas those with a ‘macho’ or ‘sweet tooth’ dietary pattern were less likely to have high blood pressure (P for trend = 0.004 and <0.001, respectively). More than half of the population had salt intakes > 9 g/d, and blood pressure increased with salt intake (P for trend <0.001). Subjects with a ‘traditional’ dietary pattern had the highest salt intake (12.3 g/d).ConclusionA traditional dietary pattern is associated with high blood pressure among the population of Jiangsu Province, which may be mainly due to high salt intake. Moreover, high BMI is an important determinant of high blood pressure. Both issues need to be addressed by lifestyle interventions.

Abstract 346: Subcutaneous Resistance Artery Remodeling And Function In Chronic Kidney Disease Patients

Background: Chronic kidney disease (CKD) is associated with cardiovascular (CV) complications. However, interventional trials targeting classical CV risks factors have been often unsuccessful in advanced stage CKD, which emphasizes the need to better understand CKD-associated vascular disorders. Resistance arteries are a key determinant of blood pressure (BP) and their changes in different CV conditions contribute to target organ damage. The aim of the present study was to characterize resistance artery remodeling and function in CKD patients, compared to vessels from hypertensive (HTN) subjects. Method: Twenty-two stage 4 CKD patients (aged 63.6±3.1 years) and 16 HTN subjects (45.6±16.1 years) were included in the present study. They all underwent a subcutaneous biopsy under local anaesthesia. Small artery remodeling and function were studied on a pressurized myograph, and subcutaneous fat CD3 infiltration and media fibronectin expression by immunostaining. Vascular smooth muscle cells (VSMCs) were counted after hematoxilin-eosin staining. Results: CKD systolic BP was similar to HTN (133±18 vs. 143±10 mmHg, respectively). Vasodilatory responses to acetylcholine were lower in CKD compared to HTN (maximal relaxation (%), 74.3±3.4 vs. 87.5±2.7, P&lt;0.05). Media/lumen at 60 mmHg was lower in CKD than in HTN (6.7±0.5 vs 8.8±0.7, P&lt;0.05). Resistance artery stiffness was lower in CKD compared to HTN (strain at 120 mmHg, 0.845±0.126 vs 0.585±0.099, P&lt;0.05). Fibronectin staining in resistance arteries was lower in CKD than HTN (8.2±0.8 vs 23.3±1.7 RFU/μm2, P&lt;0.001). Less VSMCs were present in the arterial wall of CKD compared to HTN (5.4±0.4 vs 7.2±0.5 cells/μm2, P&lt;0.05). Subcutaneous fat presented fewer CD3+ cells in CKD than HTN (12.8±4.1 vs 23.7±12.8 cells/mm2, P&lt;0.05). Conclusion: Despite higher levels of BP, resistance arteries isolated from CKD patients exhibited no vascular remodeling and lower arterial stiffness compared with HTN patients. These results are in line with the maladaptive hypotrophic remodeling observed in large vessels in CKD, suggesting a generalized vascular defect in mechanotransduction in CKD.

CPAP for excessive sleepiness in elderly patients

CPAP for excessive sleepiness in elderly patients

How much salt do adults consume in climate vulnerable coastal Bangladesh?

BackgroundEvidence from numerous studies suggests that salt intake is an important determinant of elevated blood pressure. Robust data about salt consumption among adults in Bangladesh is sparse. However, much evidence suggests saline intrusion due to sea level rise as a result of climate change exposes more than 20 million people to adverse effects of salinity through the food and water supply. The objective of our study was to assess salt consumption among adults in a coastal region of Bangladesh.MethodsOur study was cross sectional and conducted during October-November 2011. A single 24 hour urine was collected from 400 randomly selected individuals over 18 years of age from Chakaria, a rural, coastal area in Southeastern Bangladesh. Logistic regression was conducted to identify the determinants of high salt consumption.ResultsThe mean urinary sodium excretion was 115 mmol/d (6.8 g salt). Based on logistic regression using two different cutoff points (IOM and WHO), housewives and those living in the coastal area had a significantly higher probability of high salt intake compared with people who were engaged in labour-intensive occupations and who lived in hilly areas.ConclusionIt is important to create awareness about the implication of excessive salt intake on health and to develop strategies for reducing salt intake that can be implemented at the community-level. A sustainable policy for salt reduction in the Bangladeshi diet should be formulated with special emphasis on coastal areas.

Causal associations of tobacco smoking with cardiovascular risk factors: a Mendelian randomization analysis of the HUNT Study in Norway.

Tobacco smoking has been associated with cardiovascular risk factors including adverse serum lipid levels, central obesity and higher resting heart rate, but lower blood pressure and body mass index (BMI). We used a Mendelian randomization approach to study whether these associations may be causal. If smoking affects cardiovascular risk factors then rs1051730 T alleles, predictors of increased smoking quantity, should be associated with cardiovascular risk factors among smokers, but not among never smokers. Among 56,625 participants of a population-based study, we estimated associations of rs1051730 T alleles with cardiovascular risk factors and examined whether the associations differed by smoking status. Rs1051730 T alleles were associated with lower BMI and waist and hip circumferences and higher resting heart rate and estimated glomerular filtration rate (eGFR), and the associations were strongest among current smokers (P interaction 5×10(-9) to 0.01). Rs1051730 T alleles were associated with lower systolic blood pressure and pulse pressure and higher HDL cholesterol concentrations, but these associations did not robustly differ by smoking status. There were no convincing associations of rs1051730 T alleles with waist-hip ratio, diastolic blood pressure and non-fasting serum concentrations of non-HDL cholesterol, triglycerides, glucose and C-reactive protein. This Mendelian randomization analysis provides evidence that smoking may cause lower BMI and waist and hip circumferences and higher resting heart rate and eGFR. The findings further suggest that smoking is not a major determinant of waist-hip ratio or adverse blood pressure, serum lipid or glucose levels.

Estrogen signaling alterations in resistance arteries postpartum (849.6)

Few studies have examined the after‐effects of childbirth on the female vasculature – especially the resistance microvasculature of non‐reproductive tissues, which are a major determinant of blood pressure. 17β‐estradiol (E2), an important vasoactive hormone, normally declines after parturition; however, many women artificially increase estrogen levels after pregnancy by taking oral contraceptives.Our hypothesis was that parturition attenuates E2‐induced relaxation in mesenteric arteries by decreasing nNOS expression. We measured a 73% decrease in serum E2 levels in the postpartum state compared to nulliparous Sprague‐Dawley rats. We found that microvessels from postpartum animals exhibited: 1) endothelium‐independent, E2‐induced relaxation (intact 18.78 ± 3.84% vs denuded 15.37 ± 3.30%), 2) impaired E2‐induced relaxation due to decreased NOS activity (L‐NMMA, ‐17.54 ± 15.66% vs postpartum controls 12.98 ± 2.94% relaxation at 1000nM E2), 3) impaired nNOS‐dependent, E2‐induced relaxation, and 4) decreased nNOS expression (down 39% p=0.0077). Because E2 has been shown to increase nNOS protein expression, we propose that lower E2 levels after parturition decrease expression of nNOS, leading to a reduced vasodilatory capacity of resistance microvessels.Grant Funding Source: Supported in part by NIH HL073890

Associations of Birth Weight and Postnatal Weight Gain With Cardiometabolic Risk Parameters at 5 Years of Age

The present prospective study assessed the impact of birth weight (BW) and postnatal weight gain on blood pressure and metabolic profile during the first 5 years of life. One hundred thirty-nine newborns (63 women) born at term after uncomplicated pregnancies and in the absence of perinatal illness were included. Subjects were divided according to size at birth in small, appropriate, and large for gestational age. After the initial evaluation on the second day of life, infants were followed up at 6 months and 2 and 5 years. Anthropometric parameters and blood pressure were measured at each visit and metabolic assessment was performed at 5 years of age. Among the BW groups, mothers did not differ in terms of age, smoking, and weight gain during pregnancy. BW was a positive determinant of systolic blood pressure at birth. Afterward, current weight was the strongest determinant, becoming significant at 2 years of age and progressively increasing in influence. At 5 years insulin, the homeostasis model assessment index and triglycerides were dependent on BW, current weight, and postnatal weight gain. In addition, BW was positively associated with high-density lipoprotein-cholesterol and inversely so to uric acid. A positive relationship among insulin, blood pressure values, and uric acid was observed even early in life. In conclusion, the acceleration of early infant weight gain may aggravate the effects of low BW. Multiple interactions between hemodynamic and metabolic parameters foreshadow the clustering of cardiometabolic risk factors later in life.

Determinants of exercise peak arterial blood pressure, circulatory power, and exercise cardiac power in a population based sample of Finnish male and female aged 30 to 47 years: the Cardiovascular Risk in Young Finns Study

BackgroundNovel parameters derived from peak maximal oxygen uptake (VO2) and exercise arterial blood pressure, such as peak circulatory power (CP) and exercise cardiac power (ECP), can be used in the risk assessment of cardiovascular disease and stroke. However, the determinants of these factors are poorly characterized in the general population.MethodsWe assessed peak arterial blood pressure, CP and ECP with standardized cardiopulmonary exercise test (CPET) on 281 female and 257 male participants of the Cardiovascular Risk in Young Finns Study. The subjects were aged 30–47 years. Peak VO2 as well as systolic and diastolic arterial blood pressures were measured to calculate peak mean arterial pressure, CP and ECP. These parameters were assessed for correlation with sex, age, height, weight, waist-to-hip ratio, smoking, physical activity index (PAI), fasting insulin and glucose levels as well as the use of antihypertensive treatment.ResultsSex, age and weight explained 36% of the variation in peak systolic blood pressure, and these factors in combination with height and the use of antihypertensive treatment explained 13% of the variation in peak diastolic blood pressure. Sex, height, weight, waist-to-hip ratio, PAI and smoking explained 49% − 52% of the variation in peak CP. Sex, age, height, weight, waist-to-hip ratio, PAI, smoking and insulin levels explained 21% − 49% of variation in ECP.ConclusionsSubject demographics and lifestyle-related factors should be taken into account when exercise blood pressure response, CP and ECP are used to evaluate patients’ cardiac function in CPET.

Yet Another Study Reports Poor Control of Elevated Blood Pressure

The article by Sorlie et al.1 (this issue) provides estimates of the prevalence of hypertension and of awareness, treatment, and control among the Hispanic community. Previous publications from this study have described the study design and recruitment and baseline measurements2 and the distribution of risk factors and prevalent cardiovascular disease.3 The reports documented very substantial variability in the prevalence of hypertension by specific Hispanic groups and communities. The most interesting observation is the low prevalence of hypertension noted both in this and in previous publications among Mexican Americans as compared with the other groups, especially Dominicans (i.e., 13.3% of Mexican Americans in Bronx, NY; vs. 29.5% of Dominicans in Bronx, NY; vs. 21.2% of Mexicans in San Diego, CA). A previous publication noted that the diet scores were much better in the Mexican Americans than in the Dominicans or the other populations. Dietary differences could potentially explain the variations in hypertension among the populations.3 It is also possible that the lower prevalence of hypertension among Mexicans and South Americans may be a function of genetic admixture (i.e. black, white, and Indian) and possibly lifestyle interactions. Variation in the prevalence of hypertension, if not due to the above, could be related to novel determinants of blood pressure (BP) levels that are unique to ≥1 of the Hispanic populations in this study. It would be important to compare BP in the Hispanic subgroups to similar BP levels in countries of origin and try to relate BP levels, as noted, to genetic admixture, degree of acculturation, specific dietary factors, vascular structure, kidney function, and psychosocial stressors. Such studies will require much more in-depth investigation than in the parent study.4–6 Furthermore, differences in specific dietary factors as measured by metabolomics, proteomics, and amino acids, such as dietary amino acids, or differences in gut microbiology could account for differences in hypertension variation. The null hypothesis is that variation in hypertension among the Hispanic population in the study is a function of sampling of specific Census tracts and low response percentage, approximately 45%. Individuals who migrated from the high-density Census tracts would be excluded (i.e., acculturation and better education). The response to the examination (i.e., so-called white coat hypertension) could vary by center and specific Hispanic group.4 The other new information provided in the Sorlie et al. article is the documentation of very poor control of hypertension (Table 2 in the Sorlie et al. article), consistent with hypertension control in other US populations.7,8 The estimate of the lower awareness, treatment, and control of BP is, in part, an artifact of sampling BP at only 1 time point. There is substantial within-individual variability in the measurement of BP. In individuals with lower BP at 1 time, the BP on average will progress toward higher levels on repeat measurement, whereas in individuals with higher BP, the BP will regress downward toward the mean or lower levels. There are many more individuals, especially in younger age groups, with BP in the lower levels (i.e., 120 or 130 to 139 mm Hg), who, at any 1 time, will have BP >140 mm Hg (i.e., progressing upward), than there are individuals with BP >140 mm Hg whose BP on repeat measurements will drop to 140 mm Hg in this study who were classified as hypertensives will probably be found after repeat measurement to not have hypertension—that is, their BP level will regress downward to <140 mm Hg. The size of this effect is related to the within-individual variability of BP levels over time. Multiple measurements of BP over time are required to adequately classify individuals as hypertensives. Repeat measurement of BP over time is usually a better prediction of clinical events than a measurement at only 1 point.9,10 A very critical question is whether observational studies can continue to follow participants with uncontrolled hypertension and then report the higher incidence of stroke, congestive heart failure, coronary heart disease, subclinical vascular disease, and brain vascular disease, including dementia. Untreated hypertensives are at higher risk.11–13 Should the National Heart, Lung, and Blood Institute or other funding agencies provide adequate antihypertensive

Interaction between a CSK Gene Variant and Fish Oil Intake Influences Blood Pressure in Healthy Adults1,2

Blood pressure is a heritable determinant of cardiovascular disease (CVD) risk. Recent genome-wide association studies have identified several single-nucleotide polymorphisms (SNPs) associated with blood pressure, including rs1378942 in the c-Src tyrosine kinase (CSK) gene. Fish oil supplementation provides inconsistent protection from CVD, which may reflect genetic variation. We investigated the effect of rs1378942 genotype interaction with fish oil dosage on blood pressure measurements in the MARINA (Modulation of Atherosclerosis Risk by Increasing doses of N–3 fatty Acids) study, a parallel, double-blind, controlled trial in 367 participants randomly assigned to receive treatment with 0.45, 0.9, and 1.8 g/d eicosapentaenoic acid [EPA (20:5n–3)] and docosahexaenoic acid [DHA (22:6n–3)] (1.51:1) or an olive oil placebo for 12 mo. A total of 310 participants were genotyped. There were no significant associations with blood pressure measures at baseline; however, the interaction between genotype and treatment was a significant determinant of systolic blood pressure (SBP) (P = 0.010), diastolic blood pressure (DBP) (P = 0.037), and mean arterial blood pressure (MABP) (P = 0.014). After the 1.8 g/d dose, noncarriers of the rs1378942 variant allele showed significantly lower SBP (P = 0.010), DBP (P = 0.016), and MABP (P = 0.032) at follow-up, adjusted for baseline values, than did carriers. We found no evidence of SNP genotype association with endothelial function (brachial artery diameter and flow-mediated dilatation), arterial stiffness (carotid-femoral pulse wave velocity and digital volume pulse), and resting heart rate. A high intake of EPA and DHA could help protect noncarriers but not carriers of the risk allele. Dietary recommendations to reduce blood pressure in the general population may not necessarily benefit those most at risk. This trial was registered at controlled-trials.com as ISRCTN66664610.

Blood pressure level profiles among children and adolescents with various types of obesity: study in a large population in Shandong, China

It is well known that obesity is a key determinant of elevated blood pressure (BP) in children and adolescents. The present study compared the BP levels among children and adolescents with various types of obesity in a large population in China. A total of 38,822 students (19,456 boys and 19,366 girls) aged 7-17 years participated in this study. Height, weight, waist circumference (WC), and BP of all subjects were measured, and body mass index (BMI) was calculated. General obesity was assessed by BMI and central obesity by WC. All obese subjects were classified into three types: general obesity only, central obesity only and combined obesity. Relatively high BP status was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥ 95th percentile for age and gender. The overall prevalences of general obesity only, central obesity only and combined obesity were 10.38, 9.61 and 10.77 % for boys and 5.46, 11.41 and 5.44 % for girls, respectively. In both boys and girls, significant differences in BP level and the prevalence of relatively high BP were observed among the three types of obesity (P < 0.05); combined obesity group had the highest BP levels and prevalence of relatively high BP. Children and adolescents with both general and central obesity might have an increased risk of elevated BP than those with isolated types of obesity. Our results suggest that the combined measurement of BMI and WC as a screening tool for high BP among children and adolescents.

Sodium Intake and Renal Outcomes: A Systematic Review

Sodium intake is an important determinant of blood pressure; therefore, reduction of intake may be an attractive population-based target for chronic kidney disease (CKD) prevention. Most guidelines recommend sodium intake of < 2.3 g/day, based on limited evidence. We reviewed the association between sodium intake and renal outcomes. We reviewed cohort studies and clinical trials, which were retrieved by searching electronic databases, that evaluated the association between sodium intake/excretion and measures of renal function, proteinuria, or new need for dialysis. Of 4,337 reviewed citations, seven (n = 8,129) were eligible, including six cohort studies (n = 7,942) and one clinical trial (n = 187). Four studies (n = 1,787) included patients with CKD. All four cohort studies reported that high intake (> 4.6 g/day) was associated with adverse outcomes (vs. moderate/low), while none reported an increased risk with moderate intake (vs. low). Three studies (n = 6,342) included patients without CKD. Two cohort studies (n = 6,155) reported opposing directions of association between low (vs. moderate) sodium intake and renal outcomes, and one clinical trial (n = 187) reported a benefit from low intake (vs. moderate) on proteinuria but an adverse effect on serum creatinine. Available, but limited, evidence supports an association between high sodium intake (> 4.6g/day) and adverse outcomes. However, the association with low intake (vs. moderate) is uncertain, with inconsistent findings from cohort studies. There is urgent need to clarify the long-term efficacy and safety of currently recommended low sodium intake in patients with CKD.

Sarcopenia as a determinant of blood pressure in older Koreans: findings from the Korea National Health and Nutrition Examination Surveys (KNHANES) 2008-2010.

BackgroundBlood pressure (BP) is directly and causally associated with body size in the general population. Whether muscle mass is an important factor that determines BP remains unclear.ObjectiveTo investigate whether sarcopenia is associated with hypertension in older Koreans.ParticipantsWe surveyed 2,099 males and 2,747 females aged 60 years or older.MeasurementsSarcopenia was defined as an appendicular skeletal muscle mass divided by body weight (ASM/Wt) that was <1 SD below the gender-specific mean for young adults. Obesity was defined as a body mass index (BMI) ≥25 kg/m2. Subjects were divided into four groups based on presence or absence of obesity or sarcopenia. Hypertension was defined as a systolic BP (SBP) ≥140 mmHg, a diastolic BP (DBP) ≥90 mmHg, or a self-reported current use of antihypertensive medications.ResultsThe overall prevalence of hypertension in the four groups was as follows 49.7% for non-obese non-sarcopenia, 60.9% for non-obese sarcopenia, 66.2% for obese non-sarcopenia and 74.7% for obese sarcopenia. After adjustment for age, gender, regular activity, current smoking and alcohol use, the odds ratio (OR) for having hypertension was 1.5 (95% confidence interval (CI) = 1.23–1.84) in subjects in the non-obese sarcopenia group, 2.08 (95% CI = 1.68–2.57) in the obese non-sarcopenia group and 3.0 (95% CI = 2.48–3.63) in the obese sarcopenia group, compared with the non-obese non-sarcopenia group (p for trend <0.001). Controlling further for body weight and waist circumference did not change the association between hypertension and sarcopenia. The association between sarcopenia and hypertension was more robust in the subjects with diabetes mellitus.ConclusionBody composition beyond BMI has a considerable impact on hypertension in elderly Koreans. Subjects with sarcopenic obesity appear to have a greater risk of hypertension than simply obese or sarcopenia subjects.