Determinants Of Blood Pressure Research Articles

Propofol Decreases the Augmentation Index of Central Arteries via a Delay in the Pulse Wave Reflection

Background Procedural sedation with propofol is widely used to reduce stress and suppress cardiovascular responses to anxiety and fear during medical and dental treatments. A well-known adverse event of propofol is a decrease in peripheral vascular resistance resulting in hypotension; however, the effects on intravascular pressure at the central arteries are unknown. Intravascular pressure is formed by the synthesis of reflected waves from the periphery with forward pulse waves produced during ejection, and the augmented pressure by the reflected waves is one of the determinants of the systolic blood pressure (BP) at the central arteries and is known to be related to cardiovascular events. We tested the hypotheses that propofol reduces the augmentation index (AIx) in the carotid artery and that the reduction is caused by a delay in the arrival time of the reflected wave (Tr). Methods Beat-by-beat finger BP and heart rate (HR) were continuously recorded in seven healthy young men (Age: 30 ± 2 years). Central BP, AIx, Tr of the carotid artery, and carotid-to-femoral pulse wave velocity (cfPWV) were measured using applanation tonometry during supine rest before (BL) and 20 min after the onset of continuous administration of propofol (PRO). This study was approved by the Institutional Review Board of Matsumoto Dental University. Results Systolic BP was lower in PRO than in BL (P < 0.001) in both peripheral and central arteries, while it was lower in the central artery than in the peripheral artery in PRO (80 ± 5 and 96 ± 6 mmHg, P < 0.001). HR in PRO remained unchanged from BL. AIx was decreased (−40.9 ± 10.3 vs −11.8 ± 11.3%, P < 0.001), and Tr was prolonged (199 ± 14 vs 173 ± 8 ms, P < 0.001) in PRO than in BL at the carotid artery. A negative correlation was found between AIx and Tr (r = −0.91, P < 0.001). Furthermore, Tr was negatively correlated with cfPWV (r = −0.72, P = 0.004), but not with the effective reflected length (P = 0.291). Conclusions Since propofol delayed the time when the reflected wave reached the large vessels, the interval between the peaks of the forward wave and the reflected wave widened, resulting in a decreased peak value of the augmented pressure. These results suggest that the carotid artery pressure is decreased by propofol-induced reduction in augmentation pressure, which is dependent on the delay in the arrival time of the reflected wave to the central arteries.

SODIUM AND POTASSIUM INTAKE, AND KNOWLEDGE ATTITUDES AND BEHAVIOUR TOWARDS SALT CONSUMPTION: A NATIONAL SURVEY OF ADULTS IN THE SULTANATE OF OMAN

Objective: High sodium (Na) and inadequate potassium (K) intake are important determinants of high blood pressure (BP) and cardiovascular diseases (CVDs). In Oman, CVD represents a common cause of morbidity and mortality, accounting for 33.0% of all deaths. However, there is no reliable measure of Na and K intake in the Sultanate of Oman. The aim of the present survey was to establish current baseline average consumption of Na and K, and explore knowledge, attitudes and behaviour (KAB) towards the use of salt, in a nationally representative random sample of Omani adult men and women living in Oman. Design and method: The study was a national cross-sectional population-based survey of proportional random samples, representative of Omani adults (18 yrs and older), obtained from all Governorates of Oman (Figure). Of the 999 who agreed to participate, after robust quality control, 569 (193 men, 376 women; response rate 57%; mean age 39.4 yrs [SD 13.1]) were included in the final analysis. The characteristics of those excluded were comparable to those included. Participants attended a screening including demographic, anthropometric and physical measurements by standardized methods. Dietary Na (salt) and K intakes were assessed by 24 h urinary Na (UNa) and K (UK) excretions. Urinary creatinine was also measured. KAB were assessed by questionnaire. Results: Mean UNa was 144.3 (78.8) mmoL/day, equivalent to 9.0 g of salt/day and potassium excretion 52.6 (32.6) mmoL/day, equivalent to 2.36 g/day. Men ate more sodium and potassium than women. Only 22% of the sample had a salt intake below the World Health Organization (WHO) recommended target of 5 g/day and less than a quarter met WHO targets for potassium excretion (&gt;90 mmoL/day). Whilst 89.1% of those interviewed knew that consuming too much salt could cause serious health problems and only 6.9% felt they were using too much added salt, 1 in 2 participants use always or often salt, salty seasonings or salty sauces in cooking or when preparing food at home. Conclusions: In Oman, salt consumption is higher, and potassium consumption lower, than recommended by the WHO, both in men and in women.

The Calcium Signaling Mechanisms in Arterial Smooth Muscle and Endothelial Cells.

The contractile state of resistance arteries and arterioles is a crucial determinant of blood pressure and blood flow. Physiological regulation of arterial contractility requires constant communication between endothelial and smooth muscle cells. Various Ca2+ signals and Ca2+ -sensitive targets ensure dynamic control of intercellular communications in the vascular wall. The functional effect of a Ca2+ signal on arterial contractility depends on the type of Ca2+ -sensitive target engaged by that signal. Recent studies using advanced imaging methods have identified the spatiotemporal signatures of individual Ca2+ signals that control arterial and arteriolar contractility. Broadly speaking, intracellular Ca2+ is increased by ion channels and transporters on the plasma membrane and endoplasmic reticular membrane. Physiological roles for many vascular Ca2+ signals have already been confirmed, while further investigation is needed for other Ca2+ signals. This article focuses on endothelial and smooth muscle Ca2+ signaling mechanisms in resistance arteries and arterioles. We discuss the Ca2+ entry pathways at the plasma membrane, Ca2+ release signals from the intracellular stores, the functional and physiological relevance of Ca2+ signals, and their regulatory mechanisms. Finally, we describe the contribution of abnormal endothelial and smooth muscle Ca2+ signals to the pathogenesis of vascular disorders. © 2021 American Physiological Society. Compr Physiol 11:1831-1869, 2021.

Hydrogen peroxide (H2O2) mediated activation of mTORC2 increases intracellular Na+ concentration in the renal medullary thick ascending limb of Henle

Hydrogen peroxide (H2O2) production in the renal outer medulla is an important determinant of renal medullary blood flow and blood pressure (BP) salt-sensitivity in Dahl salt-sensitive (SS) rats. The mechanisms and pathways responsible for these actions are poorly understood. Recently, we have discovered that the mTOR complex 2 (mTORC2) plays a critical role in BP salt-sensitivity of SS rats by regulating Na+ homeostasis. PP242, an inhibitor of mTORC1/2 pathways exhibits potent natriuretic actions and completely prevented salt-induced hypertension in SS rats. In the present study, we have found that chronic infusion of H2O2 into the single remaining kidney of Sprague Dawley (SD) rats (3 days) stimulated the functional marker (pAKTSer473/AKT) of mTORC2 activity measured by Western Blot analysis. No changes in mTORC1 activity in OM were observed as determined by pS6Ser235/236/S6. Using fluorescent microscopy and the Na+ sensitive dye Sodium Green, we have shown that H2O2 (100 µM added in the bath) increased intracellular sodium concentration ([Na+]i) in renal medullary thick ascending limbs (mTALs) isolated from SD rats. These responses were almost completely abolished by pretreatment of mTAL with 10 µM PP242, indicating that mTORC1/2 pathways were involved in the H2O2 induced increase of [Na+]i. mTAL cell volume remained unchanged (± 1%) by H2O2 as determined by 3D reconstruction confocal laser scanning microscopy techniques. Consistent with the microscopy data, Western Blot analysis of proteins obtained from freshly isolated mTAL treated with 100 µM H2O2 exhibited increased activity/phosphorylation of AKT (pAKTSer473/AKT) that was inhibited by PP242. This was associated with increased protein activity of the apical membrane cotransporter Na+-K+-2Cl− (NKCC2) and the Na/H exchanger (NHE-3). Na+-K+-ATPase activity was increased as reflected an increase in the ratio of pNa+-K+-ATPaseSer16 to total Na+-K+-ATPase. Overall, the results indicate that H2O2 mediated activation of mTORC2 plays a key role in transducing the observed increases of cytosolic [Na+]i despite associated increases of basolateral pump activity.

Contributions of social determinants of health to systolic blood pressure in United States adult immigrants: Use of path analysis to validate a conceptual framework.

Validate a conceptual framework and identify pathways between antecedent (life-course socioeconomic status (L-SES)), predisposing (age, sex, married, homeless as a child), enabling (health literacy, acculturation), and need (disability) social determinants of health (SDoH) and systolic blood pressure (SBP) in US immigrants. 181 immigrants were enrolled in the study. Path analysis was used to identify paths by which SDoH influence SBP and to determine if antecedents, predisposing, enabling, and need factors have direct and indirect relationships with SBP. The final model(chi2(5)=14.88, p = 0.011, RMSEA = 0.070, pclose = 0.17, CFI = 0.96) showed L-SES was directly associated with age (0.12, p = 0.019) and disability(0.17, p = 0.001); and indirectly associated with disability (0.29, p < 0.001) and SBP (0.31, p < 0.001). Age (0.31, p < 0.001) and sex(0.25, p < 0.001) were directly associated with SBP, and age was directly associated with disability (0.29, p < 0.001) and indirectly associated with SBP(0.14, p = 0.018). Other predisposing factors such as being married (-0.32, p < 0.001) and being homeless as a child alone (0.16, p < 0.001) were directly associated with disability and indirectly associated (0.14, p = 0.018) with SBP. Enabling factor of health literacy (0.16, p = 0.001) was directly associated with disability and indirectly associated (0.14, p = 0.018) with SBP. Need factor of disability (0.14, p = 0.018) was directly associated with SBP. This study provides the first validation of a conceptual model for the relationship between SDoH and SBP among immigrants and identifies potential targets for focused interventions.

Rare Causes of Arterial Hypertension and Thoracic Aortic Aneurysms-A Case-Based Review.

Thoracic aortic aneurysms may result in dissection with fatal consequences if undetected. A young male patient with no relevant familial history, after having been investigated for hypertension, was diagnosed with an ascending aortic aneurysm involving the aortic root and the proximal tubular segment, associated with a septal atrial defect. The patient underwent a Bentall surgery protocol without complications. Clinical examination revealed dorso–lumbar scoliosis and no other signs of underlying connective tissue disease. Microscopic examination revealed strikingly severe medial degeneration of the aorta, with areas of deep disorganization of the medial musculo–elastic structural units and mucoid material deposition. Genetic testing found a variant of unknown significance the PRKG1 gene encoding the protein kinase cGMP-dependent 1, which is important in blood pressure regulation. There may be genetic links between high blood pressure and thoracic aortic aneurysm determinants. Hypertension was found in FBN1 gene mutations encoding fibrillin and in PRKG1 mutations. Possible mechanisms involving the renin–angiotensin system, the role of oxidative stress, osteopontin, epigenetic modifications and other genes are reviewed. Close follow-up and strict hypertension control are required to reduce the risk of dissection. Hypertension, scoliosis and other extra-aortic signs suggesting a connective tissue disease are possible clues for diagnosis.

Determinants of Blood Pressure in Neonates and Infants: Predictable Variability.

The blood pressure (BP) of neonates, especially those born premature, changes rapidly over the first days and weeks of life. Neonatal BPs may be affected by maternal factors, perinatal factors or events, and intrinsic or extrinsic infant factors. Unfortunately, the effect of many maternal health and disease states has only been studied in small numbers or has shown conflicting results. Many events around the time of delivery have the potential to influence the neonatal BP, and while definitive studies are often lacking, some observational data support physiological expectations. The strongest determinants of neonatal BP are the infant factors of gestational age at birth, birth weight, and postmenstrual age. Understanding the expected pattern of BP changes, identifying the potential influencing factors, and accurately measuring the BP are all essential to determine whether there is a BP abnormality present but are also more complex in the neonatal population. This review describes the evidence for maternal conditions, perinatal events, and infant factors to affect neonatal BP. It also explains what is currently known about the changing BP patterns in neonates including those born preterm. In addition, by examining the physiological process of hemodynamic adaptation to the extrauterine environment and compensatory cardiovascular responses, we can gain insight into the expected and unexpected vascular responses, making the variability of neonatal BP seem a little more predictable.

Internal migration, urban living, and non-communicable disease risk in South Africa.

This paper offers theoretical and substantive contributions to migration-health scholarship by employing rich panel data with biomarkers to estimate the effect of migration and urban living on non-communicable disease risk in South Africa. Internal migration and urbanization continue to be pervasive demographic and socio-economic phenomena that structure daily life in low- and middle- income countries (LMICs). Yet, how these processes affect illness and disease in low-resource settings is still not well understood. Five waves (2008-2017) of South Africa's National Income Dynamics Study data and fixed-effects modeling are used to estimate the relationship between urban residence, migration, and health. Results indicate that the migration-health relationship differs by gender: urban living for men is associated with lower blood pressure. While urban residence appears to convey a health advantage when men reside in urban compared with rural places, there is no evidence of an urban health advantage among women. Migration does, however, negatively affect women's health through higher blood pressure (BP). These findings highlight the need for further interrogation of the ways in which processes and health consequences of migration and urban living are structured by gender in LMICs. Given the importance of urbanization and the prevalence of migration in LMICs, the gendered determinants of blood pressure may be key to understanding rising hypertension incidence in contexts like South Africa.

Gender-stratified hierarchical modeling of patient and physician determinants of antihypertensive treatment outcomes: pooled analysis of seven prospective real-world studies with 17,044 patients

Objective Seven prospective real-world studies conducted in general practices in Belgium of antihypertensive treatment with valsartan-centric regimens were pooled to examine similarities and differences in determinants of blood pressure (BP) values (mmHg) and BP control rates between female and male patients. Methods Pooled analysis of a total evaluable sample of 17,044 patients, including 8273 (48.5%) women and 8771 men (51.5%) treated over approximately 90 days with valsartan-centric regimens in second or later line. Hierarchical linear and logistic regressions were applied to identify patient- and physician-related determinants of BP outcomes and a potential physician class effect. Results Reductions in BP (mmHg) over 90 days were similar for women and men, and so were changes in BP control rates. Approximately a quarter of the variance in 90 day BP values was attributable to a physician class effect. Both gender groups shared some patient- and physician-related determinants of BP outcomes, though often varying in degree of influence. Analyses also revealed gender-specific determinants. Among others, modifiable/manageable patient-related determinants included BP at hypertension diagnosis (proxy for time of diagnosis), risk factors, antihypertensive treatment and adherence; while among the physician-related determinants clinical experience in hypertension treatment was modifiable/manageable. Conclusion Valsartan-centric treatment regimens are associated with significant reductions in BP level and improvement in BP control in both women and men. The determinants revealed in modeling provide guidance to clinicians in the common and differential management of hypertension in female and male patients.

The effect of sex on vascular function during acute stress

Premenopausal women present with lower rates of hypertension compared to similarly aged men. However, the direct mechanisms contributing to this cardio-protection remain incompletely understood. Therefore, the purpose of this study was to examine the impact of peripheral neural activity (i.e. muscle sympathetic nerve activity; MSNA) on vascular function, a primary determinant of blood pressure in healthy individuals.

Renal interstitial fibroblasts coproduce erythropoietin and renin under anaemic conditions.

BackgroundErythrocyte mass contributes to maintaining systemic oxygen delivery and blood viscosity, with the latter being one of the determinants of blood pressure. However, the physiological response to blood pressure changes under anaemic conditions remain unknown.Methods and FindingsWe show that anaemia decreases blood pressure in human patients and mouse models. Analyses of pathways related to blood pressure regulation demonstrate that anaemia enhances the expression of the gene encoding the vasopressor substance renin in kidneys. Although kidney juxtaglomerular cells are known to continuously produce renin, renal interstitial fibroblasts are identified in the present study as a novel site of renin induction under anaemic hypotensive conditions in mice and rats. Notably, some renal interstitial fibroblasts are found to simultaneously express renin and the erythroid growth factor erythropoietin in the anaemic mouse kidney. Antihypertensive agents but not hypoxic stimuli induced interstitial renin expression, suggesting that blood pressure reduction triggers interstitial renin induction in anaemic mice. The interstitial renin expression was also detected in injured fibrotic kidneys of the mouse and human, and the renin-expressing interstitial cells in murine fibrotic kidneys were identified as myofibroblasts originating from renal interstitial fibroblasts. Since the elevated expression levels of renin in fibrotic kidneys along with progression of renal fibrosis were well correlated to the systemic blood pressure increase, the renal interstitial renin production seemed to affect systemic blood pressure.InterpretationRenal interstitial fibroblasts function as central controllers of systemic oxygen delivery by producing both renin and erythropoietin.FundingGrants-in-Aid from Japan Society for the Promotion of Science (JSPS) KAKENHI (17K19680, 15H04691, and 26111002) and the Takeda Science Foundation.

Relationships between advanced glycation end products (AGEs), vasoactive substances, and vascular function

Vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) are major cell types that control vascular function, and hence dysfunction of these cells plays a key role in the development and progression of vasculopathies. Abnormal vascular responsiveness to vasoactive substances including vasoconstrictors and vasodilators has been observed in various arteries in diseases including diabetes, hypertension, chronic kidney diseases, and atherosclerosis. Several substances derived from ECs tightly control vascular function, such as endothelium-derived relaxing and contracting factors, and it is known that abnormal vascular signaling of these endothelium-derived substances is often observed in various diseases. Derangement of signaling in VSMCs and altered function influence vascular reactivity to vasoactive substances and tone, which are important determinants of vascular resistance and blood pressure. However, understanding the molecular mechanisms underlying abnormalities of vascular functions in pathological states is difficult because multiple substances interact in the development of these processes. Advanced glycation end products (AGEs), a heterogeneous group of bioactive compounds, are thought to contribute to vascular dysfunction, which in turn cause the development of several diseases including diabetes, hypertension, stroke, and atherosclerosis. A growing body of evidence suggests that AGEs could affect these cells and modulate vascular function. This study is focused on the link between AGEs and functions of ECs and VSMCs, particularly the modulative effects of AGEs on vascular reactivities to vasoactive substances.

Hierarchical modeling of blood pressure determinants and outcomes following valsartan treatment in hypertensive patients with known comorbidities: pooled analysis of six prospective real-world studies including 11,999 patients

Aims Six prospective real-world studies of antihypertensive treatment with valsartan-centric regimens were pooled to: (1) examine the effectiveness of ∼90 days of second- or later-line valsartan treatment in hypertensive patients with known comorbidities; and (2) identify physician- and patient-related determinants associated with systolic (SBP) and diastolic blood pressure (DBP) outcomes in these patients. Methods and materials A pooled analysis was performed of an evaluable sample of 11,999 hypertensive patients with known comorbidities treated ∼90 days with valsartan-centric regimens. We applied hierarchical linear and logistic regression models to identify determinants of blood pressure (BP) outcomes and a potential physician class effect. Results Valsartan regimens resulted in mean (SD) SBP and DBP reductions of 18.0 (15.8) mmHg and 9.5 (10.1) mmHg, respectively, at ∼90 days, yielding SBP, DBP and combined SBP/DBP control rates of 44.0%, 67.2% and 39.3%, respectively. About a quarter of the variance in 90 day BP values was attributable to a physician class effect. BP outcomes declined with physicians’ increasing years in practice and being male. At the patient level, BP outcomes declined with SBP and DBP at diagnosis; diabetes; higher cholesterol and BMI; lower valsartan and hydrochlorothiazide (HCTZ) doses; and concomitant anti-hypertensives. Older age was associated with improved DBP. A proxy of physician vigilance, cardiovascular disease history, was associated with improved BP outcomes, as were patient adherence and higher doses of valsartan in combination with HCTZ. Conclusions Valsartan-centric regimens have significant BP lowering benefits in this pooled sample of patients with known comorbidities. Many observed determinants of BP outcomes are modifiable or manageable.

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

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

Comparison of Heart Rate Variability among Young Malay Male Adult with Different BMI and Level of Adiposity

INTRODUCTION: Subclinical changes that occur in the heart at an early age may provide valuable information to outline prevention strategies for cardiovascular diseases. Heart rate variability (HRV) reflects regulation of autonomic balance, heart, and vascular tone, which are the determinants of blood pressure. Therefore, this study aimed to determine the difference in heart rate variability (HRV) of Malay male young adult with their BMI and adiposity level. MATERIALS AND METHODS: A total of 201 Malay male young adult aged between 19 to 24 years old were screened and their BMI and adiposity level were measured. Three non -invasive tests; Valsalva Manoeuvre, orthostatic response and 30/15 ratio of heart rate were performed. Short term HRV time and frequency domains were recorded. RESULTS: Despite few significant differences in HRV parameters of overweight/obese subjects, the result is inconclusive to conclude any reduced variability. However, those with high adiposity regardless of their BMI reported significantly lower mean of R -R SD in time domain and lower mean of LF/HF ratio in frequency domain. The orthostatic reflex results revealed that high adiposity subjects had significantly lower mean of LF and HF. A decrement of -0.28 ms2 HF/LF during Valsalva manoeuvre, -0.35 LF ms2 in orthostatic reflex and 0.33 ms2 in orthostatic reflex per 1% of body fat percentage were observed. CONCLUSION: HRV parameters were inversely proportional to the adiposity level which was suggestive of modulation of sympathetic function can occur at an early age.

Early Determinants of Childhood Blood Pressure at the Age of 6 Years: The GECKO Drenthe and ABCD Study Birth Cohorts.

BackgroundThere is still uncertainty about the nature and relative impact of early determinants on childhood blood pressure. This study explored determinants of blood pressure at the age of 6 years in 2 Dutch birth cohorts.Methods and ResultsResults of hierarchical multiple linear regression analyses in GECKO (Groningen Expert Center for Kids With Obesity) Drenthe study (n=1613) were replicated in ABCD (Amsterdam Born Children and Their Development) study (n=2052). All analyses were adjusted for child's age, sex, height, and body mass index (BMI), and maternal education and subsequently performed in the combined sample. No associations were found between maternal smoking during pregnancy and childhood blood pressure. In the total sample, maternal prepregnancy BMI was positively associated with systolic blood pressure (SBP) (β [95% CI], 0.09 [0.02–0.16] mm Hg) and diastolic blood pressure (β [95% CI], 0.11 [0.04–0.17] mm Hg). Children of women with hypertension had higher SBP (β [95% CI], 0.98 [0.17–1.79] mm Hg). Birth weight standardized for gestational age was inversely associated with SBP (β [95% CI], −6.93 [−9.25 to −4.61] mm Hg) and diastolic blood pressure (β [95% CI], −3.65 [−5.70 to −1.61] mm Hg). Longer gestational age was associated with lower SBP (β [95% CI] per week, −0.25 [−0.42 to −0.08] mm Hg). Breastfeeding for 1 to 3 months was associated with lower SBP (β [95% CI], −0.96 [−1.82 to −0.09] mm Hg) compared with no or <1 month of breastfeeding. Early BMI gain from the age of 2 to 6 years was positively associated with SBP (β [95% CI], 0.41 [0.08–0.74] mm Hg) and diastolic blood pressure (β [95% CI], 0.37 [0.07–0.66] mm Hg), but no effect modification by birth weight was found.ConclusionsHigher maternal prepregnancy BMI, maternal hypertension, a relatively lower birth weight for gestational age, shorter gestational age, limited duration of breastfeeding, and more rapid early BMI gain contribute to higher childhood blood pressure at the age of 6 years.

Hypovitaminosis D, Dyslipidaemia and Thyroid Dysfunction Among Adolescents and Their Associations With Raised Blood Pressure in a North Eastern City of India

Background: Raised blood pressure (BP) has been found to be associated with serum levels of vitamin D3, lipid profile and thyroid hormones among adults. But limited information is available regarding such associations in adolescents. Objectives To estimate the prevalence vitamin D3 deficiency, dyslipidaemia and thyroid dysfunction among secondary school students of Agartala municipal corporation area and to study their associations with raised BP. Methods: This school based cross-sectional study was conducted during April 2018 to December 2018 among 1000 students studying in different secondary level schools located in Agartala municipal corporation area chosen by multi stage sampling technique ensuring proportionate representation in the sample. Result: Prevalence of vitamin D3 deficiency, thyroid dysfunction and dyslipidaemia were found to be 79.4%, 62.8% and 37.5% respectively. Out of total, 58.1% of the study subjects had raised BP, 34.1% were fatty, 16.7% were overweight, 5.3% were obese and 48.3% had high waist hip ratio (WHR). Among all, 82.27% subjects with high BMI, 70.97% fatty subjects and 69.05% subjects with either low or normal WHR had significantly elevated BP (p 0.05). Binary logistic regression has identified higher BMI, higher body fat content, high WHR, habit of consuming extra salt and fast food on regular basis as the significant determinants of raised BP in this population (p<0.05). Conclusion: Though vitamin D deficiency, thyroid dysfunction and dyslipidaemia are prevalent among adolescents of Northeast India, they did not emerge as significant determinants of blood pressure in them. Funding Statement: Department of Health Research (DHR), Ministry of Health & Family Welfare, Govt. of India, New Delhi through Multidisciplinary Research Unit, AGMC. Declaration of Interests: There is no conflict of interest. Ethics Approval Statement: Informed written consent document for participation in this study was handed over to participating students for obtaining consent from their guardians. This study was approved by the institutional ethics committee of Agartala Government Medical College.

Effect of urinary angiotensinogen and high-salt diet on blood pressure in patients with chronic kidney disease: results from the Korean Cohort Study for Outcome in Patients with Chronic Kidney Disease (KNOW-CKD).

Background/AimsThis study aimed to investigate whether urinary angiotensinogen (UAGT) excretion was associated with elevated blood pressure in patients with chronic kidney disease (CKD) and to evaluate the relationship among blood pressure, intra-renal renin-angiotensin system (RAS) activity, and dietary sodium in patients with CKD.MethodsParticipants from the Korean Cohort Study for Outcome in Patients with Chronic Kidney Disease (KNOW-CKD) were included. Of the total cohort of 2,238 individuals with CKD, we included 1,955 participants who underwent complete 24-hour urinary sodium (24-hour UNa) analysis. They were categorized into three groups according to three tertiles of their 24-hour UNa, reflecting daily salt intake. To measure intra-renal RAS activity, the UAGT excretion was assayed with an enzyme-linked immunosorbent assay.ResultsElevated 24-hour UNa levels, logarithm of UAGT-to-creatinine ratio (UAGT/Cr), increased waist-to-hip ratio, and decreased estimated glomerular filtration rate were the risk factors for increased systolic blood pressure. Systolic blood pressure showed a positive correlation with 24-hour UNa levels and logarithm of UAGT/Cr.ConclusionsUAGT and urinary sodium excretion are independent determinants of systolic blood pressure in patients with CKD. These findings suggest that increased systolic blood pressure in CKD patients is associated with both increased dietary sodium levels and intra-renal RAS activity. The risk of elevated systolic blood pressure in the 3rd tertile of both the UAGT/Cr and 24-hour UNa groups was about 2.3 times higher than that in the reference group.

Renal Interstitial Fibroblasts Coproduce Erythropoietin and Renin Under Anaemic Conditions

Erythrocyte mass contributes to maintaining systemic oxygen delivery and blood viscosity, with the latter being one of the determinants of blood pressure. However, the physiological response to blood pressure changes under anaemic conditions remain unknown. Here, we show that anaemia decreases blood pressure in human patients and mouse models. Analyses of pathways related to blood pressure regulation demonstrate that anaemia enhances the expression of the gene encoding the vasopressor substance renin in kidneys. Although kidney juxtaglomerular cells are known to continuously produce renin, renal interstitial fibroblasts are identified in the present study as a novel site of renin induction under anaemic hypotensive conditions in mice and rats. Notably, some renal interstitial fibroblasts are found to simultaneously express renin and the erythroid growth factor erythropoietin in the anaemic mouse kidney. Antihypertensive agents but not hypoxic stimuli induced interstitial renin expression, suggesting that blood pressure reduction triggers interstitial renin induction in anaemic mice. The interstitial renin expression was also detected in injured fibrotic kidneys of the mouse and human, and the renin-expressing interstitial cells in murine fibrotic kidneys were identified as myofibroblasts originating from renal interstitial fibroblasts. Since the elevated expression levels of renin in fibrotic kidneys along with progression of renal fibrosis were well correlated to the systemic blood pressure increase, the renal interstitial renin production seemed to affect systemic blood pressure. These results propose that renal interstitial fibroblasts function as central controllers of systemic oxygen delivery by producing both renin and erythropoietin.

Determinants of High Blood Pressure in Subjects Living with Type 2 Diabetes in Urban Areas in Togo

Determinants of High Blood Pressure in Subjects Living with Type 2 Diabetes in Urban Areas in Togo