2011 Jul - Fedorowski A, Hedblad B, Melander O

Center for Emergency Medicine, Skåne University Hospital, Entrance 35, Floor 2, 205 02, Malmö, Sweden. artur.fedorowski@med.lu.se

European journal of epidemiology

Orthostatic hypotension (OH) is associated with increased total mortality but contribution of specific death causes has not been thoroughly explored. In this prospective study, authors followed up 32,068 individuals without baseline history of cancer or cardiovascular disease (69% men; mean age, 46 years; range, 26-61 years) over a period of 24 years.Hazard ratios (HRs) for total and cause- specific mortality associated with presence of OH and by quartiles of postural systolic blood pressure response (∆SBP) were assessed using multivariate adjusted Cox regression model. A total of 7,145 deaths (22.3%, 9.4 deaths/1,000 person-years) occurred during follow-up. Those with OH (n = 1,943) had higher risk of death due to injury (HR, 1.88; 1.37-2.57) and neurological disease (HR, 2.21; 1.39-3.51).

2011 Jul - Israel S, Israel A, Ben-Dov IZ, Bursztyn M

Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.

American journal of hypertension

BACKGROUND: Morning blood pressure surge (MS) is accepted to increase cardiovascular risk, but it is not clear how it should be defined. Because dipping on 24-h ambulatory blood pressure monitoring (ABPM) associates with improved outcome we hypothesized that MS will not predict mortality independent of dipping. METHODS: We investigated a cohort of 2,627 patients referred for ABPM with available values for at least 1-h after awakening, and related them to all-cause mortality. RESULTS: During 22,353 person-years of follow-up, 246 patients died. We used Cox proportional hazards models to explore mortality associated with different definitions of the MS. Only the "1-h" MS (difference between average blood pressure (BP) 1-h before and after awakening) was related to mortality: after multiple adjustments including 24-h systolic BP, those whose "1-h" MS was above median (>12 mm Hg) had mortality hazard ratio (HR) of 0.61, 95% CI: 0.47-0.79, P < 0.001.

2011 Apr 6 - Gurley SB, Riquier-Brison AD, Schnermann J, Sparks MA, Allen AM, Haase VH, Snouwaert JN, Le TH, McDonough AA, Koller BH, Coffman TM

Division of Nephrology, Department of Medicine, Duke University and Durham, VA Medical Centers, Durham, NC 27710, USA.

Cell metabolism

Hypertension affects more than 1.5 billion people worldwide but the precise cause of elevated blood pressure (BP) cannot be determined in most affected individuals. Nonetheless, blockade of the renin-angiotensin system (RAS) lowers BP in the majority of patients with hypertension. Despite its apparent role in hypertension pathogenesis, the key cellular targets of the RAS that control BP have not been clearly identified. Here we demonstrate that RAS actions in the epithelium of the proximal tubule have a critical and nonredundant role in determining the level of BP. Abrogation of AT(1) angiotensin receptor signaling in the proximal tubule alone is sufficient to lower BP, despite intact vascular responses. Elimination of this pathway reduces proximal fluid reabsorption and alters expression of key sodium transporters, modifying pressure-natriuresis and providing substantial protection against hypertension.

2011 Mar 14 - Tai K, Gentilcore D, Jones KL, Banh L, Gilja OH, Hammond AJ, Feinle-Bisset C, Horowitz M, Chapman IM

Discipline of Medicine, Royal Adelaide Hospital, University of Adelaide, North Terrace, Adelaide, SA 5000, Australia.

The British journal of nutrition

Postprandial hypotension may be influenced by the digestion of fat. The aim of the present study was to evaluate the hypothesis that products of fat digestion mediate the hypotensive response to fat. In part A of the study, nine healthy older subjects were studied on three separate occasions in randomised order. Blood pressure, heart rate (HR), plasma TAG and gastric emptying were measured following the ingestion of equivolaemic drinks: (1) 300 ml of high- fat drink (88 % fat); (2) fat drink mixed with 120 mg orlistat (lipase inhibitor); (3) water (control). In part B of the study, ten healthy older subjects were studied on two separate occasions. Blood pressure, HR, plasma TAG and superior mesenteric artery flow were measured during 90 min intraduodenal infusions of 10 % intralipid (2·7 ml/min), with and without 120 mg orlistat.

2011 Mar - Huang CM, Wang KL, Cheng HM, Chuang SY, Sung SH, Yu WC, Ting CT, Lakatta EG, Yin FC, Chou P, Chen CH

Department of Medicine, Yuanshan Veterans Hospital, Yilan, Taiwan.

Journal of hypertension

OBJECTIVES: Central systolic (SBP-C) and/or pulse pressure (PP-C) better predicts cardiovascular events than does peripheral blood pressure. The present study compared the prognostic significance of office central blood pressure with multiple measurements of out-of-office ambulatory peripheral blood pressure, with reference to office peripheral systolic (SBP-B) or pulse pressure (PP-B). METHODS: In a community-based population of 1014 healthy participants, SBP-C and PP-C were estimated using carotid tonometry, and 24-h systolic (SBP-24 h) and pulse pressure (PP-24 h) were obtained from 24-h ambulatory blood pressure monitoring. Associations of SBP-B, PP-B, SBP-C, PP-C, SBP-24 h, and PP-24 h with all-cause and cardiovascular mortalities over a median follow-up of 15 years were examined by Cox regression analysis. RESULTS:

2011 Mar - Bailey MA, Craigie E, Livingstone DE, Kotelevtsev YV, Al-Dujaili EA, Kenyon CJ, Mullins JJ

British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom. matthew.bailey@ed.ac.uk

Hypertension

Salt sensitivity of blood pressure is an independent risk factor for cardiovascular morbidity.Mechanistically, abnormal mineralocorticoid action and subclinical renal impairment may blunt the natriuretic response to high sodium intake, causing blood pressure to rise. 11β-Hydroxysteroid dehydrogenase type 2 (11βHSD2) controls ligand access to the mineralocorticoid receptor, and ablation of the enzyme causes severe hypertension. Polymorphisms in HSD11B2 are associated with salt sensitivity of blood pressure in normotensives. In this study, we used mice heterozygote for a null mutation in Hsd11b2 (Hsd11b2(+/-)) to define the mechanisms linking reduced enzyme activity to salt sensitivity of blood pressure. A high-sodium diet caused a rapid and sustained increase in blood pressure in Hsd11b2(+/-) mice but not in wild-type littermates. During the adaptation to high-sodium diet, heterozygotes displayed impaired sodium excretion, a transient positive sodium balance, and hypokalemia.

2011 Feb - Muntner P, Shimbo D, Tonelli M, Reynolds K, Arnett DK, Oparil S

Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA. pmuntner@uab.edu

Hypertension

Recent data suggest that visit-to-visit variability of blood pressure is associated with stroke incidence.Correlates of increased visit-to-visit variability in blood pressure and the relationship between variability and all -cause mortality were examined using data on US adults ≥ 20 years of age from the Third National Health and Nutrition Examination Survey (n = 956). Three consecutive blood pressure readings were taken during 3 separate study visits from 1988 to 1994. Based on the mean of the second and third measurements from each visit, visit-to-visit blood pressure variability for each participant was defined using the standard deviation and coefficient of variation across visits. Mortality was assessed through December 31, 2006 (median follow-up = 14 years; n = 240 deaths). The mean of the standard deviation for systolic blood pressure across visits was 7.7 mm Hg.

2011 Feb - Lohmann FW, Eckert S, Verberk WJ

Departments of Internal Medicine, Charité University Medicine and Vivantes Klinikum Neukölln Hospital, Berlin, Germany.

Blood pressure monitoring

OBJECTIVE: To compare two methods for screening interarm difference (IAD) of blood pressure. MATERIAL AND METHODS: This study compared two methods for double-arm measurements: (i) conventional measurement (CM) and (ii) simultaneous automatic measurement (SAM). A total of 118 patients with two or more cardiovascular risk factors and a mean age of 59±17 years were referred to two internal clinics. CM was taken with a validated aneroid manometer in sitting position on the right and left arm subsequently and vice versa. SAM was taken three times in sitting position using a validated automatic oscillometric device equipped with two cuffs for simultaneous double-arm measurements. RESULTS: The average absolute IAD of the conventional systolic value (4.9 mmHg) was significantly higher than the average absolute IAD of the SAM pressures averaged from two (3.7 mmHg; P<0.03) and three measurements (3.8 mmHg; P<0.05).

2011 Feb - Korkmaz S, Yıldız G, Kılıçlı F, Yılmaz A, Aydın H, Içağasıoğlu S, Candan F

Gemerek Devlet Hastanesi, İç Hastalıkları Bölümü, Sivas, Türkiye.

Anadolu kardiyoloji dergisi : AKD = the Anatolian journal of cardiology

OBJECTIVE: The nocturnal blood pressure (NBP) reduction is less than normal in the patients with type 2 diabetes mellitus (type 2 DM). L-carnitine deficiency may cause changes of NBP by leading to hyperglycemia, insulin resistance and endothelial dysfunction in patients with type-2 DM. The purpose of the study was to investigate whether there is a difference in levels of L-carnitine in dipper and nondippers patients with type 2 DM. METHODS: This is a cross-sectional observational cohort study. We compared the 50 (33 females, 17 males) patients with type 2 DM and the 35 healthy persons (18 females, 17 males) as a control group. In all cases, ambulatory blood pressure monitoring (ABPM) was performed and L-carnitine was measured. The independent samples t test, Chi-square test, Mann-Whitney U test and Pearson correlation analysis were used in the statistical evaluation of data. RESULTS: We found that the percentage of nondipper pattern was 72% in patients with type 2 DM.

2010 Dec - Bartoli E, Carnevale Schianca GP, Sainaghi PP

Internal Medicine, Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi del Piemonte Orientale A. Avogadro, Via Solaroli, 17, 28100 Novara, Italy. bartoli@med.unipmn.it

European journal of internal medicine

The effectiveness of hypertension treatments is attributed either to the change in blood pressure, independent of the means used, or to an important contribution of appropriate drug selection: this debate probably stems from an inappropriate comparison.Treating essential hypertension in relatively healthy patients without advanced vascular disease and co-morbidities affords cardio-vascular protection by the lowering of the mechanical shear stress determined by blood pressure per se: thus, lowering blood pressure is the critical step, while the methods used can only differ through side effects. This treatment is, in fact, a lifetime prophylaxis, as hypertension, rather than a disease, is a symptom affecting one tail of the Gaussian distribution of blood pressure across the normal population.