Both Blood Pressure Research Articles

Ambient PMs Pollution, Blood Pressure, Potential Mediation by Short-Chain Fatty Acids: A Prospective Panel Study of Young Adults in China

BackgroundThe concurrent effects of particulate matter (PM) on both blood pressure (BP) and short-chain fatty acids (SCFAs) are insufficiently explored, with limited research on the potential mediating roles of SCFAs. MethodsIn this prospective panel study with 4 follow-ups, we recruited 40 college students in Hefei, China, to assess the impacts of short-term exposure to PM (aerodynamic diameter ≤10 μm (PM10), ≤2.5 μm (PM2.5), and ≤1 μm (PM1)) on BP and SCFAs, along with potential mechanisms. Real-time PM data, urinary SCFAs levels, and BP indicators were systematically collected. Linear mixed-effects models assessed the relationships between PM, SCFAs, and BP. Mediation analyses explored SCFAs’ mediating role in the PM-BP association. ResultsPM exposure was positively linked to BP and negatively associated with SCFAs. For a 10μg/m3 rise in PM10 at lag 0-72h, there were notable reductions of 0.0019% (95%CI: -0.0028, -0.0010) in Acetic acid, 0.0262% (-0.0369, -0.0155) in Propionic acid, and 0.0702% (-0.1025, -0.0378) in Butyric acid. Systolic BP, diastolic BP, and mean arterial pressure (MAP) increased by 2.60mmHg (0.96, 4.25), 2.24mmHg (1.18, 3.31), and 2.36mmHg (1.20, 3.53), respectively, per 10-μg/m3 rise in PM1 at lag 0-24h. Decreased SCFAs levels explained significant portions (24.69% to 31.80%) of the elevated MAP due to PM10. Stronger associations were found in females and individuals with abnormal BMI. ConclusionsOur study shows that PM exposure decreases urinary SCFAs levels, which partially mediate the impact of PM on elevated BP. These findings enhance our comprehension of the pathways linking PM exposure to BP changes.

Ambulatory arterial stiffness index, mortality, and adverse cardiovascular outcomes; Systematic review and meta-analysis.

The ambulatory arterial stiffness index (AASI) is a novel measure of both blood pressure (BP) variability and arterial stiffness. This systematic review and meta-analysis was designed to evaluate the strength of the association between AASI and mortality and major adverse cardiovascular events (MACE). PubMed, Scopus, CINAHL, Google Scholar. and the Cochrane library were searched for relevant studies to July 31, 2023. Two investigators independently extracted data. The Newcastle-Ottawa Scale (NOS) was used to assess the quality of all included articles. The relationship between baseline AASI and outcomes were examined using relative risk (RR) ratios with 95% confidence intervals (CI) with RevMan web. Thirteen studies were included and representing 28 855 adult patients who were followed up from 2.2 to 15.2 years. A 1-standard deviation (1-SD) increase in AASI was associated with a significant increase in all-cause death (RR 1.12; 95% CI: 0.95-1.32), stroke (RR 1.25; 95% CI: 1.09-1.44), and MACE (RR 1.07; 95% CI: 1.01-1.13; [I2 =32%]). Higher dichotomized AASI (above vs. below researcher defined cut-offs) was associated with a significant increase in all-cause mortality (RR 1.19; 95% CI: 1.06-1.32), cardiovascular death (RR 1.29; 95% CI: 1.14-1.46), stroke (RR 1.57; 95% CI: 1.33-1.85), and MACE (RR1.29; 95% CI: 1.16-1.44). There was a significant risk of bias in more than 50% of studies with no evidence of significant publication bias. Higher AASI is associated with an increased risk of all-cause and cardiovascular death, stroke, and MACE. Further high-quality studies are warranted to determine reproducible AASI cut-offs to enhance its clinical risk precision.

Sex and molecular differences in cardiovascular parameters at peak influenza disease in mice.

There is a growing interest in the detection of subtle changes in cardiovascular physiology in response to viral infection to develop better disease surveillance strategies. This is not only important for earlier diagnosis and better prognosis of symptomatic carriers but also useful to diagnose asymptomatic carriers of the virus. Previous studies provide strong evidence of an association between inflammatory biomarker levels and both blood pressure (BP) and heart rate (HR) during infection. The identification of novel biomarkers during an inflammatory event could significantly improve predictions for cardiovascular events. Thus, we evaluated changes in cardiovascular physiology induced in A/Puerto Rico/8/34 (PR8) influenza infections in female and male C57BL/6J mice and compared them with the traditional method of influenza disease detection using body weight (BW). Using radiotelemetry, changes in BP, HR, and activity were studied. Change in BW of infected females was significantly decreased from 5 to 13 days postinfection (dpi), yet alterations in normal physiology including loss of diurnal rhythm and reduced activity was observed starting at about 3 dpi for HR and 4 dpi for activity and BP; continuing until about 13 dpi. In contrast, males had significantly decreased BW 8 to 12 dpi and demonstrated altered physiological measurements for a shorter period compared with females with a reduction starting at 5 dpi for activity, 6 dpi for BP, and 7 dpi for HR until about 12 dpi, 10 dpi, and 9 dpi, respectively. Finally, females and males exhibited different patterns of inflammatory maker expression in lungs at peak disease by analyzing bulk RNA-sequencing data for lungs and Bio-plex cytokine assay for blood collected from influenza-infected and naïve C57BL/6J female and male mice at 7 dpi. In total, this study provides insight into cardiovascular changes and molecular markers to distinguish sex differences in peak disease caused by influenza virus infection.NEW & NOTEWORTHY This study performed longitudinal cardiovascular measurements of influenza viral infection and identified sex difference in both physiological and molecular markers at peak disease.

Beliefs, behaviour, and blood pressure: preliminary analysis from a pharmacy-based hypertension visualisation intervention to support medication adherence

Abstract Introduction Hypertension is the leading preventable risk factor for cardiovascular disease, with an estimated prevalence of 31% worldwide1. Antihypertensive medication reduces both blood pressure (BP) and cardiovascular risk; however, approximately 50% of patients become nonadherent to antihypertensives within a year of treatment initiation2. Nonadherence can be considered as either intentional or unintentional. Research suggests that rather than being a solely passive process, illness beliefs and treatment perceptions may influence nonintentional nonadherence3, highlighting the importance of considering patients’ beliefs when supporting adherence. The use of visuals is one method to aid understanding of complex health information and influence treatment beliefs. Aim To investigate the feasibility and acceptability of a community pharmacy-based visualisation intervention (ViSTA-BP) and explore the preliminary effect on patients’ perceptions of hypertension, medication adherence and blood pressure. Methods ViSTA-BP is a digital intervention that allows users, through real-time animations, to visualise both the condition that is hypertension and how blood pressure affects the circulatory system. The purpose of ViSTA-BP was to improve patients’ understanding of hypertension, increase perceived necessity of treatment and ultimately support medication adherence. A mixed-methods pre-post design pilot study was conducted. NHS Research Ethics Committee Wales Rec 5 (reference 20/WA/0280) and Cardiff Metropolitan University (reference PGR-3806) granted ethical approval. The intervention was consultation-based and researcher-facilitated. Outcomes were recorded at baseline, immediately post-intervention, and at three-months. Validated questionnaires were used to measure illness and treatment beliefs (Brief Illness Perception Questionnaire (B-IPQ)/Beliefs about Medicines Questionnaire (BMQ)), adherence captured using self-report measures (Medicines Adherence Rating Scale (MARS-5)/recent adherence questionnaire) and medication dispensing/collection data. BP was measured at baseline and 3-month follow-up. Semi-structured interviews with patients and pharmacists explored intervention acceptability. Results Pharmacists recruited 69 patients with hypertension across five community pharmacies (CP) in South Wales; 54 attended the three-month follow-up. The ease of participant recruitment and high retention rates demonstrated the feasibility of delivering ViSTA-BP in this setting. ViSTA-BP content and the CP location were acceptable to patients and pharmacists. Time to deliver the intervention was a concern for pharmacists but not patients. There was no statistically significant change in adherence outcomes at three-month follow-up; however, the median scores for both self-report questionnaires were maximal at baseline. Changes were seen in illness belief scores, with a significant improvement in total B-IPQ score over time (p=0.04). Significant changes in B-IPQ treatment control (p=0.01), illness coherence (p<0.001) and BMQ Necessity subscale scores (p=0.003) were reported at all time-points. There was a statistically significant improvement in both systolic (SBP) (p<0.01) and diastolic BP (DBP) (p=0.03) three-months post-intervention. At baseline, 31% of participants had SBP at or below the UK target; however, at three-month follow-up, 59% were at or below the UK target. Discussion/Conclusion ViSTA-BP was considered a feasible researcher-facilitated intervention in this CP setting. Improvements seen in blood pressure control, patients’ understanding of hypertension, and perceptions of utility and necessity of treatment highlight the potential for the ViSTA-BP intervention to help reduce cardiovascular risk in the future. While preliminary analysis shows promise, further adequately powered research studies are necessary to evaluate future ViSTA-BP impact.

Abstract P085: Sex Differences In Cardiovascular Measurements And Inflammatory Markers At Peak Influenza Infection In Mice

For better infectious disease surveillance, there is a growing interest in the detection of subtle changes in cardiovascular physiology in response to viral infection. This is not only important for earlier diagnosis and better prognosis of symptomatic carriers, but also useful to diagnose asymptomatic carriers of the virus. Previous studies and literature provide strong evidence of an association between inflammatory biomarker levels and changes in both blood pressure (BP) and heart rate (HR). Thus, the identification of novel biomarkers during an inflammatory event could significantly improve predictions for cardiovascular events. We saw changes in cardiovascular physiology can be induced and detected in A/Puerto Rico/8/34 (PR8) influenza infections in female and male C57B6/j mice. Using PA-C10 implanted radio telemeter devices, we were able to track changes in BP, heart rate HR, and activity. Infected females showed reduction in normal physiology for approximately 10 days during infection including loss of diurnal rhythm and reduced activity starting at about 3 dpi for HR and 4 dpi for activity and BP; this continued until about 13 dpi. Males on the other hand had less reduction in physiological measurements for a shorter period compared to females with a reduction starting at 5 dpi for activity, 6 dpi for BP, and 7 dpi for HR until about 12 dpi, 10 dpi, and 9 dpi, respectively. Lastly, we found females and males had different patterns of inflammatory maker expression in lungs at peak infection by analyzing bulk RNA sequencing (RNA-seq) data for lungs and Bio-plex cytokine assay for blood collected from influenza infected (n=6) and naïve (n=6) C57B6/j female and male mice at 7 dpi.

Effect of dry body weight on intra-dialytic hypertension in patients on regular hemodialysis

Background: In chronic kidney disease, hypertension is influenced by both blood pressure (BP) and the progression of renal disease. In end stage renal disease (ESRD) on maintenance hemodialysis, hypertension is a main feature and more than 85% of new patients with ESRD present with hypertension. The aim of this study: was to assess the relationship between dry body weight and intra-dialytic hypertension in patients on regular hemodialysis. Patients and Methods: This was an observational cohort study with retrospective data analysis including (age and sex matched) patients with end stage renal disease. The study will be conducted in Nephrology Unit national institute of nephrology &urology. Results: there was statistically significant difference found between the two studied groups regarding LL edema, Sacral edema, Pl. effusion, Increased cardio/thoracic ratio, and Increased IVC diameter with (p-value= 0.016, 0.027, 0.019, 0.003 and 0.008) respectively. Conclusion: IDH is preventable if we control modifiable risk factors such as, reducing interdialytic weight gain, correction of serum albumin and urea reduction ratio. This will reduce cardiovascular morbidity and mortality in CKD patients on maintenance hemodialysis.

Associations of long-term exposure to air pollution with blood pressure and homocysteine among adults in Beijing, China: A cross-sectional study

BackgroundStudies on the hypertensive effect of long-term exposure to air pollution are mixed, and sparse evidence exists regarding its effects on homocysteine (Hcy), another crucial risk factor for cardiovascular disease (CVD). MethodsWe collected data from 23,256 participants aged 18–74 years at baseline (years 2017–2018) from a community-based cohort in China. A linear combination of concentrations from monitoring stations at the participants’ home and work addresses, weighted by the time, was used to estimate two-year exposures to particulate matter with fine particles≤2.5 μm (PM2.5), aerodynamic diameter≤10 μm (PM10), nitrogen dioxide (NO2) and sulfur dioxide (SO2). Generalized linear regressions and logistic regressions were conducted to examine the associations between air pollution and systolic blood pressure (SBP), diastolic blood pressure (DBP), Hcy, hypertension and co-occurrence of hypertension and hyperhomocysteinemia (HHcy). ResultsThe results showed that each interquartile range (IQR) increase in PM2.5 (16.1 μg/m3), PM10 (19.3 μg/m3) and SO2 (3.9 μg/m3) was significantly associated with SBP (changes: 0.64–1.86 mmHg), DBP (changes: 0.35–0.70 mmHg) and Hcy (changes: 0.77–1.04 μmol/L) in the fully adjusted model. These air pollutants were also statistically associated with the prevalence of co-occurrence of hypertension and HHcy (ORs: 1.22–1.32), which were stronger than associations with the prevalence of hypertension (ORs: 1.09–1.19). The hypertensive effects of exposure to PM2.5, PM10 and SO2 were more pronounced among elder participants, obese participants, those with established CVD or a high 10-year CVD risk and those with a family history of hypertension. However, interaction analyses of Hcy showed different patterns. Additionally, moderate level of physical activity and active travel mode benefited individuals in resisting the health impacts of air pollution on both blood pressure (BP) and Hcy. ConclusionsOur study supports a positive relationship between air pollution and BP and Hcy among adults in Beijing, and close attention to vulnerable populations and healthy lifestyles could effectively benefit further cardiovascular health.

Abstract 13354: Effectiveness of a Complex Intervention Based on Electronic Decision Support to Improve Management of Cardiovascular Disease Risk in Primary Healthcare: A Cluster-randomised Controlled Trial

Introduction: Cardiovascular disease (CVD) risk management is suboptimal in Australian primary healthcare. Following trials demonstrating efficacy of individual components, we developed a complex intervention comprised primarily of electronic point-of-care decision support, availability of cardiovascular polypills and a pharmacy-based adherence program. We sought to determine whether this combined multifaceted intervention, compared with usual care, would improve control of CVD risk factors in the Australian primary care setting. Methods and Results: In a parallel-arm cluster randomized trial, 71 general practices were allocated 1:1 either to the intervention or usual care. The primary outcome was the proportion of patients at high CVD risk and not on optimal preventive treatments at baseline (“high-risk under-treated”) achieving both blood pressure (BP) and low density lipoprotein (LDL) cholesterol targets at study end (BP ≤140/90 mmHg, or ≤130/80 mmHg in people with diabetes or albuminuria; LDL <2.0 mmol/L). All outcomes were evaluated using automated extracts from the electronic medical record. After a median period of 15 months follow-up, among 4477 high-risk under-treated patients in whom follow-up data were available, there was a negligible difference between randomized groups in the proportion achieving SBP and LDL cholesterol targets (19.6% vs. 20.1%; RR 1.06 [95% CI: 0.85 to 1.32]; p=0.59). There was also no major impact of the intervention on any pre-specified secondary outcomes, mostly relating to risk factor screening, preventive medication prescription and risk factor levels. Uptake of all components of the intervention was poor, with greatest use observed for the electronic decision support component (used at least once in 10.7% of high-risk under-treated patients) and minimal use of the other two interventions. Conclusions: Despite the proven efficacy of individual components, this complex multifaceted intervention was poorly adopted and did not lead to relevant improvements in cardiovascular risk factor outcomes.

Technology Development for Simultaneous Wearable Monitoring of Cerebral Hemodynamics and Blood Pressure.

For many cerebrovascular diseases both blood pressure (BP) and hemodynamic changes are important clinical variables. In this paper, we describe the development of a novel approach to noninvasively and simultaneously monitor cerebral hemodynamics, BP, and other important parameters at high temporal resolution (250Hz sampling rate). In this approach, cerebral hemodynamics are acquired using near infrared spectroscopy based sensors and algorithms, whereas continuous BP is acquired by superficial temporal artery tonometry with pulse transit time based drift correction. The sensors, monitoring system, and data analysis algorithms used in the prototype for this approach are reported in detail in this paper. Preliminary performance tests demonstrated that we were able to simultaneously and noninvasively record and reveal cerebral hemodynamics and BP during people's daily activity. As examples, we report dynamic cerebral hemodynamic and BP fluctuations during postural changes and micturition. These preliminary results demonstrate the feasibility of our approach, and its unique power in catching hemodynamics and BP fluctuations during transient symptoms (such as syncope) and revealing the dynamic features of related events.

A2866 Blood Pressure and Renal Sodium Excretion in African and European Men on a High sodium diet

Objectives: Sodium plays a major role in the regulation of blood pressure. Both blood pressure (BP) and sodium retention in the kidney have both been linked to creatine kinase (CK), the enzyme that rapidly regenerates ATP for ATPases involved in pressor responses and salt retention: ADP + P∼creatine < = > ATP + Creatine.Therefore, we assessed BP and urinary sodium excretion (U_Na+) after a high sodium diet in in African and European men with high and low CK Methods: Sixty healthy men (29 European and 31 African ancestry) 18–50 y, normotensive or with uncomplicated untreated primary hypertension, were assigned to low sodium (LS) intake (<50 mmol/d) during 7 days, followed by 3 days of high sodium (HS) intake (>200 mmol/d). On day 7 (LS) and day 10 (HS), participants collected 24-h urine for U_Na+; and body weight, resting sitting blood pressure, 24 h BP, pulse wave velocity (PWV), central BP were measured (Arteriograph) Results: Table 1. depicts baseline parameters. Mean 24-h urinary sodium excretion during LS was 31.5 (3.5) and HS was 320.0 (21.1) mmol/24-h (p < 0.001), indicating adequate diet compliance. Sitting systolic and diastolic BP increased significantly during high salt as expected, with significantly higher 24 h BP and central systolic BP in African ethnicity (Table 2). PWV did not significantly differ between ethnic groups 6.4 (0.1) vs 6.6 (0.2). Sodium excretion (mmol/24-h) after high sodium was 260.4 (28.3) in the high CK tertile versus 415.2 (26.3) mmol/24-h in the low CK tertile (p < 0.001), with a decrease in urinary sodium excretion of 98.4 mmol/24-h for each increase in log CK, adjusted for age and African ancestry (Figure). Conclusion: Men of African ancestry have higher peripheral and central systolic but not diastolic blood pressures and lower sodium and potassium excretion after a high salt load.

Availability and use of home blood pressure measurement in the Czech general population

BackgroundHome blood pressure monitoring (HBPM) is recommended for hypertensive patients as a tool to improve both blood pressure (BP) control and compliance with treatment. MethodsWe evaluated the use of HBPM in hypertensive subjects examined during a cross-sectional general population survey (Czech post-MONICA). Models predicting the availability and use of HBPM were constructed using univariate and multivariate logistic regression. ResultsOf 449 treated hypertensive patients (mean age 63.2 years, 52.1% women), 250 (55.7%) reported that they had a device for BP monitoring available at home. The factors associated with HBPM availability were older age, university education, marital status, longer duration of hypertension and nonsmoking. Of the 250 subjects with HBPM available, 40% used HBPM regularly (at least once a week), and this ratio increased with the number of antihypertensive drugs taken (monotherapy 30%, dual combination 43%, combination of ≥3 drugs 48%; ptrend=0.028). BP control was similar in those using HBPM regularly and those who used HBPM irregularly or did not use it at all (54.5 vs. 49.7%; p=0.52). ConclusionHBPM is available to more than a half of treated hypertensive patients from the general population. However, only minority of the patients perform home blood pressure measurement regularly.

Visit‐to‐visit systolic blood pressure variability predicts all‐cause and cardiovascular mortality after lacunar infarct

Both blood pressure (BP) and its variability (BPV) are established risk factors for development of atherosclerotic disease and are associated with an increased risk for cardiovascular and all-cause mortality. The prognostic implications of outpatient clinic visit-to-visit BPV amongst patients with lacunar infarction are nevertheless unknown. The clinical outcome of 281 patients with lacunar infarction was prospectively followed up. The average BP and BPV, as determined by the standard deviation of the systolic and diastolic BP, were recorded during a mean 13 ± 6 outpatient clinic visits. The mean age of the population was 70 ± 10 years. After a mean 78 ± 18 months follow-up, 65 patients died (23%), 31% (20/65) due to cardiovascular causes; 14% and 7% developed recurrent stroke and acute coronary syndrome. After adjusting for age, sex, mean systolic and diastolic BP, cardiovascular risk factors and comorbidities, patients with a systolic BPV of the third tertile had significantly higher risk of all-cause mortality [hazard ratio (HR) 1.97, 95% confidence interval (CI) 1.02-3.80, P = 0.04) and cardiovascular mortality (HR 7.64, 95% CI 1.65-35.41, P < 0.01) than those with systolic BPV of the first tertile. Nevertheless, systolic BPV did not predict recurrent stroke or acute coronary syndrome. Diastolic BPV did not predict various adverse clinical outcomes. Visit-to-visit systolic BPV predicts long-term all-cause and cardiovascular mortality after lacunar infarct, independent of conventional risk factors including average BP control.

Apelin acts in the subfornical organ to influence neuronal excitability and cardiovascular function

Apelin is an adipocyte-derived hormone involved in the regulation of water balance, food intake and the cardiovascular system partially through actions in the CNS. The subfornical organ (SFO) is a circumventricular organ with identified roles in body fluid homeostasis, cardiovascular control and energy balance. The SFO lacks a normal blood-brain barrier, and is thus able to detect circulating signalling molecules such as angiotensin II and leptin. In this study, we investigated actions of apelin-13, the predominant apelin isoform in brain and circulatory system, on the excitability of dissociated SFO neurons using electrophysiological approaches, and determined the cardiovascular consequences of direct administration into the SFO of anaesthetized rats. Whole cell current clamp recording revealed that bath-applied 100 nm apelin-13 directly influences the excitability of the majority of SFO neurons by eliciting either depolarizing (31.8%, mean 7.0 ± 0.8 mV) or hyperpolarizing (28.6%, mean -10.4 ± 1.8 mV) responses. Using voltage-clamp techniques, we also identified modulatory actions of apelin-13 on specific ion channels, demonstrating that apelin-13 activates a non-selective cationic conductance to depolarize SFO neurons while activation of the delayed rectifier potassium conductance underlies hyperpolarizing effects. In anaesthetized rats, microinjection of apelin into SFO decreased both blood pressure (BP) (mean area under the curve -1492.3 ± 357.1 mmHg.s, n = 5) and heart rate (HR) (-32.4 ± 10.39 beats, n = 5). Our data suggest that circulating apelin can directly affect BP and HR as a consequence of the ability of this peptide to modulate the excitability of SFO neurons.

Acute blood pressure and urinary responses to single dose combinations of captopril and diuretics in conscious spontaneously hypertensive rats.

The present studies involved oral administration of captopril alone or in combination with individual diuretics in conscious, freely-moving spontaneously hypertensive rats (SHR). Both blood pressure (BP) and urinary fluid and electrolyte excretion were concomitantly measured. Captopril, 10 mg kg-1, caused a decrease in BP (-18 +/- 3 mm Hg) which was not significantly different from control (-10 +/- 2 mm Hg). Diuretics alone also failed to alter BP. However the BP-lowering effect of captopril was readily potentiated by concomitant administration of a single oral dose of frusemide (10 and 30 mg kg-1) in proportion to the magnitude of urinary loss. Hydrochlorothiazide at 1 and 3 mg kg-1 oral and metolazone at 0.3 and 1 mg kg-1 oral induced fluid loss similar to frusemide at 10 mg kg-1 and all produced comparable BP reduction in combination with captopril (25-32 mm Hg). Triamterene did not increase fluid excretion and was ineffective. In SHR with bilateral ureteral ligation, the synergistic effect of frusemide was abolished while that of hydrochlorothiazide still occurred with a delayed onset. It is concluded that concomitant measurement of BP and urinary excretion in conscious, freely-moving SHR is a useful technique for studying new antihypertensive drugs. Using this preparation it was found that enhancement of the acute hypotensive response to captopril with concomitant diuretic therapy occurs within 10 min and is primarily related to the fluid and Na loss, regardless of the diuretic agent used.

Association of nighttime hypertension with central arterial stiffness and urinary albumin excretion in dipper hypertensive subjects

Both blood pressure (BP) non-dipping and nighttime hypertension have been associated with accelerated target-organ damage (TOD). However, increased nighttime BP in subjects with a dipping circadian BP profile has never been reported or associated with TOD. Here, we investigated the relationships of nighttime BP with indices of vascular and kidney damage in dipper hypertensive subjects. We studied 402 subjects with untreated stage I-II essential hypertension. According to ambulatory BP recordings, 127 dipper subjects were selected and subdivided into nighttime hypertensives (NH, n = 69) (nighttime BP ≥ 120/70) and nighttime normotensives (NN, n = 50) (nighttime BP <120/70 mm Hg). All participants underwent echocardiographic examination and assessments of carotid-to-femoral pulse wave velocity (c-f PWV), albumin-to-creatinine ratio (ACR), metabolic profile and high sensitivity C-reactive protein (hs-CRP) level. Compared with NN dippers, NH dippers had higher c-f PWV (P < 0.001), ACR values (P = 0.01) and hs-CRP levels (P < 0.001). Multiple regression analysis showed that nighttime BP was more correlated with c-f PWV and ACR than was daytime BP. Among dippers, nighttime BP is associated more closely with c-f PWV and ACR than is daytime BP. These findings imply that even in dippers, absolute nighttime BP values should be taken into account when predicting surrogate end points such as arterial stiffness and urinary albumin excretion.

Associations of the -344 T&gt;C and the 3097 G&gt;A Polymorphisms of CYP11B2 Gene With Hypertension, Type 2 Diabetes, and Metabolic Syndrome in a French Population

Aldosterone can affect both blood pressure (BP) and glucose metabolism. We assessed the association of two polymorphisms -344 T>C and the 3097 G>A in the aldosterone synthase gene (CYP11B2) with prevalent and incident hypertension (HT), type 2 diabetes (T2D), and the metabolic syndrome (MetS). We studied the 5,212 participants to D.E.S.I.R. (Data from Epidemiologic Study on the Insulin Resistance syndrome), a cohort from French general population. Genotyping was done by a TaqMan assay. Analysis of covariance, multivariate logistic regression (adjusted for age, MetS components) and haplotype analysis were performed. The prevalences and 9-year incidences were 16.7 and 36.1% for HT, 2.6 and 6.2% for T2D, and 19.3 and 25.1% for the MetS. Risk for incident HT was reduced with the AA genotype of 3097 G>A, adjusted odds ratios (OR): 0.67; p = 0.04. The prevalence of HT was lower in women carrying the C allele of -344 T>C, OR 0.75; p = 0.03 for the TC genotype and 0.69; p = 0.03 for the CC genotype. In men, incident T2D was associated with both polymorphisms, adjusted OR for -344 T>C: 1.63; p = 0.04 for TC genotype and 2.12; p = 0.008 for CC genotype; for the 3097 G>A: the AA genotype was associated with a lower risk, OR 0.23; p = 0.02. In men, incident MetS was associated with 3097 G>A, OR: 0.57; p = 0.02 for AA genotype. Significant associations between haplotype combinations and the prevalence or incidence of the three diseases were also found. The -344 T>C and 3097 G>A polymorphisms in the CYP11B2 are associated with T2D, hypertension and the MetS in European subjects with gender variations.

Temperature and Blood Pressure Following Amlodipine Overdose

The cardiovascular system participates in both blood pressure (BP) and temperature regulation. As a result, salt ingestion creates conflict between BP and temperature homeostasis, as vasodilatation that would promptly lower the BP would simultaneously increase cutaneous blood flow, thereby accelerating heat loss. If temperature homeostasis has precedence over blood pressure homeostasis, as postulated by the thermoregulatory-vascular remodeling (TVR) hypothesis, then in order to minimize heat loss, BP remains elevated following salt ingestion until the kidneys excrete the excess salt. A case of amlodipine overdose offered an opportunity to test a corollary of the TVR hypothesis: vasodilators should cause a drop in body temperature and/or an increase in the metabolic rate. Following the ingestion of 1000 mg of amlodipine, the temperature and BP of a single patient were monitored during the initial 36 hours and during the 13th day of hospitalization. The BP dropped markedly between the fifth and seventh hours postingestion, but then rose steadily and normalized by 28 hours postingestion. The temperature was normal at 7 hours postingestion, declined gradually between the seventh and 26th hours postingestion, stabilized between the 26th and 31st hours postingestion, then began to rise. During this case of amlodipine overdose, a modest temperature decline lagged behind a marked BP decline. As the BP rose, the temperature also rose, but lagged behind the BP increases. These findings suggest that there is a relationship between BP and temperature and are consistent with the TVR hypothesis.

Relationships between Endogenous Sex Hormone Concentrations and Vascular Function in Postmenopausal Women

Differences in postmenopausal endogenous sex hormone concentrations are associated with varying risks of a growing number of common diseases. The relationships between postmenopausal endogenous sex hormone concentrations and vascular function are not well understood. We examined in postmenopausal women the relationships between endogenous sex hormone concentrations and both blood pressure (BP) and renal vascular resistance (RVR), at baseline and in response to infused angiotensin II (AngII). SUBJECTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: A total of 34 hypertensive, postmenopausal women were studied in low-sodium and/or high-sodium balance. Serum estradiol, serum progesterone, BP, and RVR were measured at baseline. BP and RVR were remeasured after AngII infusion. In low-sodium balance, the increases in systolic and diastolic BP in response to infused AngII were blunted with increased serum progesterone concentrations (P < 0.05). The increase in RVR in response to infused AngII was also blunted with increased serum progesterone concentrations (P < 0.005). The relationships between progesterone concentration and vascular response to AngII were independent of age, body mass index, and estradiol concentration. There were no significant correlations between estradiol concentration and BP or RVR response to AngII. There were no significant correlations between sex hormone concentrations and baseline BP or RVR. In high-sodium balance, there were no significant associations between sex hormone concentrations and vascular measures. In postmenopausal women in low-sodium balance, the pressor and renovascular responses to AngII are blunted with increased endogenous progesterone concentrations. Our findings suggest a role for endogenous progesterone in modulating vascular function, even within the low postmenopausal range.

Spontaneous Resolution of Idiopathic Aldosteronism After Long-Term Treatment With Potassium Canrenoate

To the Editor: Primary aldosteronism (PA) is the most common form of secondary hypertension. The prevalence of PA is raised from 1% to 3% to 10% to 15% because of the introduction of the upright plasma aldosterone/plasma renin activity ratio (APR) as screening procedure.1 The pathogenesis of idiopathic PA (IPA), which accounts for 50% of the cases of PA, is still not clear, and several factors have been involved, such as hypersensitivity to angiotensin II or to other stimulating factors or aberrant receptors in the glomerulosa. IPA is usually treated with aldosterone receptor blockers, such as spironolactone, potassium canrenoate (KC), canrenone, or eplerenone, which have, respectively, a high (spironolactone), low (KC and canrenone), or quite absent (eplerenone) antiandrogen activity. The dose of these drugs can be progressively reduced to the lowest amount able to keep normal both blood pressure (BP) and serum potassium. In a previous study,2 we reevaluated 15 patients with IPA 1 month after withdrawal of therapy with KC after 3 to 24 years of treatment. One month after withdrawal, APR was increased only …

Synergism of hydrochlorothiazide and nitrendipine on reduction of blood pressure and blood pressure variability in spontaneously hypertensive rats

To investigate the possible synergism of hydrochlorothiazide and nitrendipine on reducing both blood pressure (BP) and blood pressure variability (BPV) in spontaneously hypertensive rats (SHR). Seventy animals were randomly divided into seven groups. The doses were 5 and 10 mg/kg for nitrendipine, 10 and 20 mg/kg for hydrochlorothiazide and 10 + 5, 20 + 10 mg/kg, respectively, for the combination of these two drugs and 0.8% carboxymethylcellulose as control. The drugs were given via a catheter of gastric fistula. BP was then continuously recorded for 5 h from 1 h before drug administration to the end of 4th hour after drug administration, in conscious and freely moving rats. The effects on both BP and BPV reduction of the combination of hydrochlorothiazide and nitrendipine were greater than the single drug in SHR. The two drugs possessed an obvious synergism on both systolic blood pressure (q = 1.79 with small dose and q = 1.23 with large dose) and systolic blood pressure variability reduction (q = 1.79 with small dose and q = 1.39 with large dose) in SHR. The present work clearly demonstrated that there was a synergistic effect between hydrochlorothiazide and nitrendipine in lowering and stabilizing BP in SHR.