Plasma fibrinogen and incident hypertension in the Atherosclerosis Risk in Communities (ARIC) Study

Race- and Sex-Specific Factors Associated With Age-Related Slopes in Systolic Blood Pressure: Findings From the CARDIA Study

BACKGROUND

Although blood pressure (BP) increases throughout young adulthood for most individuals, the age-related slope is not uniform. This study aimed to assess associations of demographic, clinical, behavioral, psychosocial, and neighborhood characteristics with age-related BP slope among 4 race-sex groups who participated in the Coronary Artery Risk Development in Young Adults study.

METHODS

Individuals (n=3554) aged 18 to 30 years were included in this analysis if they had normal BP at baseline and ≥2 BP measurements during the years 1985/1986 to 2015/2016. Associations of exposure variables with systolic BP slope were assessed using multivariate linear models.

RESULTS

Over a mean follow-up of ~30 years, greater decade increases in systolic BP were estimated among Black than White participants (mean difference between Black females and White females: 3.0 mm Hg/decade; between Black males and White males: 4.7 mm Hg/decade). The exposure risk factors associated with greater increases in systolic BP throughout adulthood varied by race and sex. None of these factors were associated with increases in systolic BP in all race-sex groups. Parent history of high BP was associated with a steeper positive slope among Black females (effect size per decade: 1.1 [95% CI, 0.6-1.6]; P<0.01), Black males (0.6 [95% CI, 0.02-1.2]; P<0.05), and White females (0.6 [95% CI, 0.2-1.0]; P<0.01). Other risk factors were associated with greater age-related yearly increases in systolic BP among 1 or 2 of the 4 race-sex groups or were not statistically significant.

CONCLUSIONS

Culturally tailored BP reduction approach should be considered in conjunction with primordial prevention, to moderate increases in BP throughout adulthood.

Inflammatory Markers and Mortality in Diabetic Versus Idiopathic Gastroparesis

INTRODUCTION

Markers of systemic inflammation have been shown to be elevated in patients with gastroparesis (Gp). We hypothesized the presence of elevated markers of inflammation and/or coagulation can predict death in gastroparesis.

METHODS

Retrospective evaluation of 396 patients with symptoms of gastroparesis with baseline measures of inflammation and coagulation, using a database of patients from 2001 through 2011 followed for an additional 5 plus years. Patients were divided into two groups; diabetic (DM; n=137) and non-diabetic (non-DM; n=259). Inflammation, evaluated by C-reactive protein (CRP), and coagulation by fibrinogen by factor VIII assays, was compared to patient mortality, reported as death during the follow-up period.

RESULTS

Six DM and 13 non-DM patients died during the study period. DM patients had higher fibrinogen, CRP, and factor VIII levels of 454.0±135.2, 4.0±6.3, and 168±63.5, versus non-DM whose levels were 410.4±127.9, 2.6±4.9, 140.4±127.9, p=0.03, 0.001, and <0.001 respectively. Hypercoagulability risk differed by DM status (37% Vs. 29%, p=0.08). Compared to living non-DM, deceased non-DM/idiopathic patients had lower factor VIII (142.3±51.2 vs 117.7±40.3, p=0.07). The majority of deceased non-DM patients had abnormal fibrinogen (62%) but CRP and factor VIII were normal (80% and 85% respectively).

CONCLUSIONS

In this sample of 396 patients with symptoms of gastroparesis, systemic inflammation and coagulopathy appear related to diabetes mellitus. Patients who died had markers of inflammation and coagulation that differed from those still alive. Further analysis may suggest a link between inflammation, hypercoagulability, and the mechanism for mortality in gastroparesis or as a marker of disease severity.

Elevated blood viscosity is associated with cerebral small vessel disease in patients with acute ischemic stroke

BACKGROUND

Increased level of blood viscosity, which is one of the major factors that determine blood rheology, has been reported as a risk factor or predictor for cerebrovascular events. We investigated how blood viscosity is associated with acute stroke and chronic radiological manifestations of cerebral small vessel disease, and how blood viscosity changes after stroke.

METHODS

We prospectively enrolled consecutive patients with acute ischemic stroke. Whole blood viscosities at a low or high shear rate were measured using a scanning capillary tube viscometer, and were referred to as diastolic blood viscosity (DBV) and systolic blood viscosity (SBV), respectively. Correlations between blood viscosity and acute stroke etiology or chronic radiological manifestations of cerebral small vessel disease were investigated. The temporal profiles of blood viscosity at the onset of stroke and follow-up at 1 and 5 weeks were investigated.

RESULTS

Of the 127 patients admitted with acute ischemic stroke, 63 patients were included in the final analyses. DBV at the onset of stroke was significantly higher in small artery occlusion (SAO) stroke than in other stroke subtypes (p = 0.037). DBV showed a significant positive correlation with the number of chronic lacunes (r = 0.274, p = 0.030). The temporal profiles of DBV in SAO stroke showed a transient decrease due to the hydration therapy after 1 week and recurrent elevation at 5 week follow-up (p = 0.009).

CONCLUSIONS

Our study suggests that elevated DBV may play a role in the development of acute and chronic manifestations of cerebral small vessel disease. The recurring elevation of DBV in SAO stroke indicates that sufficient hydration and additional therapeutic interventions targeting blood viscosity may be needed in patients with SAO stroke.

Endothelial Damage and Hemostatic Markers in Patients with Uncomplicated Mild-to-Moderate Hypertension and Relationship with Risk Factors

Endothelial damage, high fibrinogen levels, and platelet activity are the important accelerating factors for the development of hypertension (HT). von Willebrand factor (vWF; endothelial damage marker), fibrinogen levels, and platelet aggregability were compared between patients with uncomplicated, mild-to-moderate hypertension and healthy subjects. The relationship between traditional cardiovascular risk factors and endothelial damage and prothrombotic state was evaluated. One hundred sixty-nine (54 males, 115 females) patients with untreated and uncomplicated mild-to-moderate HT, and age, gender, and body mass index-matched 124 (58 males, 83 females) healthy subjects were enrolled in this study. Plasma vWF, fibrinogen levels, adenosine diphosphate-induced platelet aggregability, insulin, glucose, serum lipids, and uric acid were measured. Patients with HT had significantly increased fibrinogen, vWF, platelet number and aggregability induced by adenosine diphosphate, triglycerides, total/HDL-C, glucose, uric acid levels, and insulin resistance than control group. vWF and hemostatic markers were comparable between smoker and nonsmoker subjects. Platelet aggregability was positively related to systolic and diastolic blood pressure, and vWF. Fibrinogen was positively associated with body mass index (BMI), systolic and diastolic blood pressure, total cholesterol (TC), uric acid, vWF, and insulin resistance. vWF was significantly related to age, systolic blood pressure, TC, LDL-C, and total/HDL-C. Systolic blood pressure was independently related to vWF. vWF and diastolic blood pressure were significant predictors for adenosine diphosphate-induced platelet aggregability. Systolic blood pressure and vWF were independent predictors for fibrinogen levels. Uncomplicated mild-to-moderate HT had endothelial damage and is associated with a prothrombotic state. Traditional cardiovascular risk factors such as age, BMI, dyslipidemia, and insulin resistance are important contributors to the development of endothelial damage and a prothrombotic state. Therefore, it is important to control these cardiovascular risk factors along with proper treatment of HT for preventing target organ damage in mild-to-moderate HT.

Relation of C-reactive protein, fibrinogen, and cardiorespiratory fitness to risk of systemic hypertension in men

We investigated the relation between inflammation and incident hypertension, independent of obesity, and tested the associations of cardiorespiratory fitness (fitness) and indexes of inflammation for the development of hypertension in 2,475 normotensive men. Inflammatory markers were C-reactive protein (CRP) and fibrinogen. Fitness was directly measured by peak oxygen uptake during sign/symptom-limited treadmill exercise testing to volitional fatigue; 266 men (10.7%) developed hypertension during an average of 4 years follow-up. After adjusting for potential confounding variables, the relative risk (RR) and 95% confidence interval (CI) for incident hypertension in those in the upper tertile versus lower tertile were 1.55 (95% CI 1.15 to 2.09) for CRP and 1.51 (95% CI 1.10 to 2.06) for fibrinogen. Although the association between fibrinogen and incident hypertension persisted after adjusting for body mass index (p = 0.049), the relation between CRP and incident hypertension was no longer statistically significant (p = 0.08). Fit men had a 27% decreased (RR 0.73, 95% CI 0.56 to 0.94) risk of incident hypertension compared with unfit men in a multivariable adjusted model. In the joint analysis, unfit men with upper CRP had 1.81 times (95% CI 1.21 to 2.70) and unfit men with upper fibrinogen had 2.03 times (95% CI 1.33 to 3.12) greater risks of incident hypertension compared with fit men with low CRP and fibrinogen, respectively. However, these risks did not significantly increase in fit men with upper CRP (RR 1.12, 95% CI 0.76 to 1.63) and fibrinogen (RR 1.26, 95% CI 0.86 to 1.85) groups. In conclusion, these results suggest that heightened levels of fibrinogen, but not CRP, are associated with incident hypertension, independent of body weight, and that high fitness attenuates the risk of incident hypertension across upper levels of inflammatory markers in men.

Prevalence and determinants of hypertension in Estonian adults

Background: Although Eastern Europe, including Estonia, has one of the highest morbidity and mortality rates associated with hypertension, there is little information in the literature concerning the biochemical risk factor profile or its association with hypertension in Estonia. This study examined the cross-sectional gender-stratified association between biochemical risk markers and hypertension in a population-based sample of adults in Estonia. Methods: The study was carried out in Tallinn, Estonia and consisted of 511 men and 600 women with a mean age of 46 years. Physiological measurements were taken and blood samples drawn to measure the following markers: cholesterol, high- and low-density lipoprotein cholesterol, apolipoproteins A-1 and B, lipoprotein(a), triglycerides, glucose, fibrinogen, high-sensitivity C-reactive protein and homocysteine. Results: Overall, 36% of participants had hypertension, with approximately 80% being aware of their condition. A total of 40% of participants reported taking antihypertensive medication. Multivariate binary logistic regression analysis showed that a decrease in high-density lipoprotein cholesterol and increases in age, body mass index, apolipoprotein B, triglyceride and homocysteine levels were associated with an increased probability of hypertension. Conclusions: Elevations in biochemical markers and cardiovascular risk factors are associated with hypertension. Increasing body mass index, triglyceride, apolipoprotein B and homocysteine levels with decreasing high-density lipoprotein cholesterol level should be investigated and monitored in Estonian adults.

The relationship between inflammation, obesity and risk for hypertension in the Multi-Ethnic Study of Atherosclerosis (MESA)

It has been suggested that inflammation is important in the aetiology of hypertension and that this may be most relevant among obese persons. To study this, we examined the independent relationships between obesity, inflammation-related proteins (interleukin-6 (IL-6), C-reactive protein (CRP) and fibrinogen) and risk for hypertension in the Multi-Ethnic Study of Atherosclerosis (MESA). Hypertension status, defined as a blood pressure ≥140/90 mm Hg or a history of hypertension and use of blood pressure medications, was determined at baseline and two subsequent exams over 5 years. Among 3543 non-hypertensives at baseline, 714 individuals developed incident hypertension by Exam 3. Cox proportional hazard models were used to determine the relationship between baseline levels of IL-6, CRP and fibrinogen and future risk of hypertension. One s.d. difference in baseline concentration of IL-6, CRP or fibrinogen was associated with 20-40% greater risk of incident hypertension. This risk was attenuated after accounting for other hypertension risk factors (hazard ratio (HR) IL-6: 1.13 (95% CI: 1.04-1.23); CRP: 1.11 (95% CI: 1.02-1.21); fibrinogen 1.0 (95% CI: 0.92-1.08)). Conversely, obesity was an independent risk factor for hypertension risk, minimally impacted by other covariates, including IL-6 and CRP (HR 1.72 (95% CI: 1.36-2.16)). IL-6 and CRP did not modify the relationship between obesity and hypertension, though an adjusted twofold greater risk was observed for obese individuals with a CRP >3 mg l⁻¹ compared with CRP <1 mg l⁻¹. The relationship between inflammation-related proteins and hypertension risk was predominantly explained by other hypertension risk factors. Obesity, independent of inflammation, remained a potent risk factor for future hypertension.

Antihypertensive pharmacogenetic effect of fibrinogen-beta variant -455G>A on cardiovascular disease, end-stage renal disease, and mortality: the GenHAT study

OBJECTIVE

The FGB gene codes for fibrinogen-beta, a polypeptide of the coagulation factor fibrinogen, which is positively associated with cardiovascular diseases. Studies show that angiotensin-converting enzyme (ACE) inhibitors lower plasma fibrinogen concentrations, whereas diuretics and calcium-channel blockers do not. As carriers of the FGB-455 minor 'A' allele have higher levels of fibrinogen while ACE inhibitors lower it, we hypothesize that 'A' allele carriers benefit more from antihypertensive treatment with ACE inhibitors than calcium-channel blockers or diuretics, relative to 'GG' genotype individuals.

METHODS

The Genetics of Hypertension Associated Treatment (GenHAT) study [ancillary to Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)] genotyped hypertensive participants for several hypertension-related candidate genes, making this a post-hoc analysis of a randomized trial. In total, 90.1% of the ALLHAT population was successfully genotyped for FGB-455. We included participants (n=30 076) randomized to one of three antihypertensive medications (lisinopril, amlodipine, chlorthalidone), with two treatment comparisons: lisinopril versus chlorthalidone and lisinopril versus amlodipine. The primary outcome of ALLHAT/GenHAT was coronary heart disease, defined as fatal coronary heart disease or non-fatal myocardial infarction, and secondary outcomes included stroke, heart failure, all-cause mortality, and end-stage renal disease (ESRD) with mean follow-up time of 4.9 years. Genotype-by-treatment interactions (pharmacogenetic effects) were tested with the Cox regression.

RESULTS

Stroke: common 'GG' homozygotes had higher risk on lisinopril versus amlodipine [hazard ratio (HR)=1.38, P<0.001], whereas minor 'A' allele carriers had slightly lower risk (HR=0.96, P=0.76; P value for interaction=0.03). Mortality: 'GG' homozygotes had higher risk on lisinopril versus amlodipine (HR=1.12, P=0.02) or chlorthalidone (1.05, P=0.23), whereas 'A' allele carriers had slightly lower risk (HR=0.92, P=0.33 for lisinopril versus amlodipine; HR=0.88, P=0.08 for lisinopril versus chlorthalidone; P value for interactions 0.04 and 0.03, respectively). ESRD: 'GG' homozygotes had higher risk on lisinopril versus chlorthalidone (HR=1.27, P=0.08), whereas 'A' allele carriers had lower risk (HR=0.64, P=0.12; P value for interaction=0.03).

CONCLUSION

There was evidence of pharmacogenetic effects of FGB-455 on stroke, ESRD, and mortality, suggesting that relative to those homozygous for the common allele, variant allele carriers of the FGB gene at position -455 have a better outcome if randomized to lisinopril than chlorthalidone (for mortality and ESRD) or amlodipine (for mortality and stroke). For the models in which a pharmacogenetic effect was observed, the outcome rates among 'GG' homozygotes were higher in those randomized to lisinopril versus amlodipine or chlorthalidone, whereas minor 'A' allele carriers had lower event rates when randomized to lisinopril versus the other medications.

Markers of inflammation and hemodynamic measurements in obesity: Copenhagen City Heart Study

BACKGROUND

Low-grade chronic inflammation has been proposed to play a major role in the pathogenesis of hypertension. Low-grade chronic inflammation is also closely associated with obesity, an established causative factor in the development of hypertension. The purpose of this study was to investigate the relationship between two markers of inflammation, C-reactive protein (CRP) and fibrinogen, and blood pressure (BP) and other hemodynamic variables in obese subjects.

METHODS

From a large cardiovascular study based in the general population, we selected subjects with a body mass index (BMI) > or =30 kg/m2, free of major cardiovascular diseases, not taking BP-lowering or lipid-lowering drugs (n = 487; women = 51.1%; median (5th to 95th percentile) age = 62 years (36-80)). The cardiovascular study included measurements of traditional and new risk factors, including ankle brachial BP index, a measure of subclinical atherosclerosis. CRP was determined by a high-sensitive assay.

RESULTS

In partial Spearman rank correlation analysis, adjusted for age and sex, we found no significant relationships between either CRP or fibrinogen and systolic BP, diastolic BP, pulse pressure, or ankle brachial index (rho: -0.057 to 0.068; P > 0.13). However, fibrinogen and CRP were found to be significantly related to heart rate (rho: 0.127-0.169; P < 0.01).

CONCLUSIONS

In this study of generally healthy obese subjects from the general population, we found no significant relationships between markers of inflammation and systolic BP or diastolic BP, showing that obese subjects with higher levels of inflammatory markers do not have higher BP levels than their obese counterparts with lower levels of inflammatory markers.

Haemorheological, platelet and endothelial indices in relation to global measures of cardiovascular risk in hypertensive patients: a substudy of the Anglo-Scandinavian Cardiac Outcomes Trial

INTRODUCTION AND METHODS

We tested the hypothesis that there was a significant relationship between haemorheological markers [white blood cell count (WCC), plasma viscosity (PV), haematocrit (HCT) and fibrinogen], as well as plasma von Willebrand factor (vWf, an index of endothelial damage/dysfunction) and soluble P-selectin (sP-sel, an index of platelet activation), to five global measures of cardiovascular risk [i.e. Framingham coronary heart disease (CHD), stroke and cardiovascular death score, the Pocock cardiovascular risk score and the sum of individual risk factors].

RESULTS

Men with a high (> or = median, n = 156) Framingham 10-year CHD risk score had higher levels of WBC (P = 0.027), fibrinogen (P = 0.012) and vWF (P = 0.002) than 153 men with results < median. Men with a high 10-year stroke risk score had significantly higher levels of fibrinogen (P = 0.01) and vWF (P < 0.0001). In stepwise linear regression analysis in men, vWF and fibrinogen were independent predictors of the number of risk factors (P < 0.0001), whilst WCC, vWF and fibrinogen emerged as independent predictors of Framingham CHD risk (P < 0.0001), and fibrinogen and vWF predicted Framingham stroke risk (R(2) = 0.089, P < 0.0001). vWF, PV and fibrinogen were predictors of Pocock cardiovascular death risk (P < 0.0001) but vWF was the only independent predictor of Framingham cardiovascular death risk (P = 0.001).

CONCLUSIONS

Abnormal haemorheological factors (particularly high plasma fibrinogen levels) and endothelial damage/dysfunction (high vWF), but not platelet activation (sP-sel), are related to established cardiovascular and death risk scores. This relationship was most evident amongst male 'high-risk' hypertensive subjects.

Plasma levels of complement C3 is associated with development of hypertension: a longitudinal cohort study

Hypertension has been associated with raised plasma levels of complement factor 3 and 4 (C3 and C4). The nature of this association is unclear. This population-based longitudinal study explored whether C3 or C4 is associated with development of hypertension. Blood pressure and plasma levels of C3 and C4 were determined in 2178 healthy men, aged 35-50 years, initially without treatment for hypertension. Incidence of hypertension and blood pressure increase over 15.7 (+/-2.2) years follow-up was studied in relation to C3 and C4 at baseline. Among men with initially normal blood pressure (<160/95 mm Hg), incidence of hypertension (>or=160/95 mm Hg or treatment) was 32, 42, 37 and 47%, respectively, for men with C3 in the first, second, third and fourth quartile (trend: P=0.001). This relationship remained significant after adjustment for confounding factors. Among men without blood pressure treatment, systolic BP increase (mean+standard error, adjusted for age, initial blood pressure and follow-up time) was 17.5+0.8, 19.6+0.9, 19.8+0.8 and 20.8+0.8 mm Hg, respectively, in the C3 quartiles (trend: P=0.004). C3 was not associated diastolic blood pressure at follow-up. Although C4 was associated with blood pressure at the baseline examination, there was no relationship between C4 and development of hypertension or future blood pressure increase. It is concluded that C3 in plasma is associated with future blood pressure increase and development of hypertension.

Positive Association Between Plasma Fibrinogen Level and Incident Hypertension Among Men

Elevated plasma fibrinogen is implicated in cardiovascular disease. However, it is not clear whether fibrinogen levels predict the development of hypertension. We examined the relationship between plasma fibrinogen level and hypertension in a population-based cohort study of 3654 participants (mean age: 61.5 years; range: 49 to 84 years) at the baseline examination (1992-1994) in the Blue Mountains region, west of Sydney, Australia, who were examined 5 years (1997-1999) later. Main outcomes of interest were prevalent hypertension (systolic blood pressure >or=140 mm Hg, diastolic blood pressure >or=90 mm Hg, or a combination of self-reported hypertension diagnosis and use of antihypertensive medications) at baseline (n=2212/3180) and 5-year incidence of hypertension among baseline normotensive individuals (n=361/637). Elevated plasma fibrinogen level was positively associated with prevalent hypertension both among men and women and positively associated with 5-year incident hypertension among men, independent of several cardiovascular risk factors. Multivariable odds ratio (95% CI) of 5-year incident hypertension comparing tertile 3 of plasma fibrinogen (>or=3.9 g/L) with tertile 1 (<or=3.2 g/L) was 1.95 (1.03 to 3.68; P trend=0.040). This prospective association, however, was not observed in women (odds ratio; 95% CI) comparing tertile 3 versus tertile 1 of plasma fibrinogen (1.00; 0.54 to 1.86; P trend=0.986). Subgroup analyses stratified by smoking, body mass index, diabetes, and blood pressure categories supported this male gender-specific pattern of association. These data provide prospective epidemiological evidence of an essential link between plasma fibrinogen level and incident hypertension among men but not among women, a finding consistent with that observed in the Atherosclerosis Risk in Communities Study.

Common carotid arterial interadventitial distance (diameter) as an indicator of the damaging effects of age and atherosclerosis, a cross-sectional study of the Atherosclerosis Risk in Community Cohort Limited Access Data (ARICLAD), 1987-89

Background

The effect of age on common carotid artery diameter is unclear for varying atherosclerosis risk levels.

Methods

Cross-sectional data from the Atherosclerosis Risk in Communities Limited Access Data set were used to estimate the association of age with B-mode ultrasound common carotid artery diameter for three atherosclerosis risk levels. Based on information from clinical examinations, B-mode ultrasounds, questionnaires, blood and other tests, participants were categorized into three groups: pre-existing disease (prevalent stroke and/or coronary heart disease), high risk group (no pre-existing disease, but prevalent diabetes, hypertension, plaques/shadowing, body mass index >= 30, current smoking, or hyperlipidemia), and a low risk group (no pre-existing disease, no plaques/shadowing, and no major elevated risk factors). Multivariable linear regression analyses modeled the common carotid artery diameter relationship with age.

Results

Age was positively and significantly associated with common carotid artery diameter after risk factor adjustment in the overall sample, but age had a larger effect among persons with evidence of atherosclerosis (interaction p < 0.05). Each year of older age was associated with 0.03 mm larger diameter/year among persons with pre-existing disease, with 0.027 mm larger diameter/year in the high risk group, but only 0.017 mm/year among the low risk group. Results were qualitatively similar using plaques/shadowing status to indicate atherosclerosis severity.

Conclusion

The significant impact of age on common carotid artery diameter among low risk, middle-aged, black and white men and women suggests arterial remodelling may occur in the absence of identified risk factors. The significantly larger impact of age among persons with, compared to persons without identified atherosclerosis or its risk factors, suggests that arterial remodelling may be an indicator of exposure duration.

New risk factors for atherosclerosis in hypertension: focus on the prothrombotic state and lipoprotein(a)

Although adequate control of blood pressure is of basic importance in cardiovascular prevention in hypertensive patients, correction of additional risk factors is an integral part of their management. In addition to classical risk factors, epidemiological research has identified a number of other conditions that might significantly contribute to cardiovascular risk in the general population and might achieve specific relevance in patients with high blood pressure. In fact, more than 20% of patients with premature cardiovascular events do not have any of the traditional risk factors and, although effective intervention on blood pressure and additional risk factors has significantly reduced cardiovascular morbidity and mortality, the contribution to stroke, coronary artery disease and renal failure is still unacceptably high. Evaluation of new risk factors may further expand our capacity to predict atherothrombotic events when these factors are included along with the traditional ones in the assessment of global cardiovascular risk in hypertensive patients. Because it could be anticipated that the role of these novel factors will become increasingly evident in the future, researchers with an interest in hypertension and physicians dealing with problems related to cardiovascular prevention should give them appropriate consideration. This review summarizes the basic biology and clinical evidence of two emerging risk factors that are reciprocally related and contribute to the development and progression of organ damage in hypertension: the prothrombotic state and lipoprotein(a).

Association Between Factor VII Polymorphisms and Blood Pressure

The purpose this study was to determine whether Arg353Gln and −323Del/Ins polymorphisms of factor VII (FVII) are related to blood pressure levels and hypertension. Subjects were drawn from the Stanislas Cohort, a longitudinal, familial French cohort examined twice since 1994. The “blood pressure study” included 1342 subjects free of medication use that could affect blood pressure. The “hypertension study” included 645 normotensive and 77 hypertensive adult subjects. Association with hypertension was also studied in 547 hypertensives enrolled in a clinical trial and in 624 normotensives drawn from the Stanislas Cohort. In the “blood pressure study,” parents with the 353Gln or −323Ins allele had lower blood pressures than did noncarriers at each examination, independent of covariates (0.01≤ P ≤0.05, except for diastolic blood pressure [DBP] at baseline, where P =0.103). Similarly significant relations were observed in their offspring ( P ≤0.05, except for systolic blood pressure [SBP] at 5 years, where P =0.186). In a representative subgroup of 267 individuals, the −323Del/Ins polymorphism was significantly associated with plasma FVII levels in both parents and offspring ( P <0.001). FVII levels in plasma were significantly correlated with SBP and DBP in parents but not in offspring. After inclusion of both FVII levels and the −223Del/Ins in the same model in parents, only FVII levels remained significantly associated with SBP and DBP. The “hypertension study” revealed that the 353Gln and −323Ins alleles were related to decreased risk (odds ratio [OR]=0.554, 95% confidence interval [CI], 0.362 to 0.848, and OR=0.475, 95% CI, 0.299 to 0.755, respectively). These results suggest that the FVII gene may be a susceptibility locus for hypertension.

Relationship of homocysteine to markers of platelet and endothelial activation in "high risk" hypertensives: a substudy of the Anglo-Scandinavian Cardiac Outcomes Trial

OBJECTIVE

To examine the relationship between plasma homocysteine (HCY) and rheological, endothelial and platelet markers in "high risk" hypertensive patients.

DESIGN

Cross-sectional study.

SUBJECTS AND METHODS

A total of 165 consecutive hypertensive patients (136 male; mean age 63 years (S.D. 8)) at high risk of cardiovascular disease who screened for inclusion in the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) were studied along with 38 population normotensive healthy controls. We measured levels of plasma homocysteine [high pressure liquid chromatography (HPLC)], soluble P-selectin, a marker of platelet function, von Willebrand factor (vWF), an index of endothelial damage/dysfunction [both by ELISA] and fibrinogen (CLAUSS). The Framingham cardiovascular and cerebrovascular risk scores were calculated.

RESULTS

Hypertensives had significantly higher blood pressure (BP) [165/90(16/10) vs. 138/82(12/8) mm Hg, p<0.0001], sP-sel [54(44-67) vs. 45(35-57) ng/ml, p=0.002], vWF [133(34) vs. 110(28) IU/dl, p<0.0001], and fibrinogen [2.98(2.52-3.47) vs. 2.43(2.20-2.83)g/l, p=<0.0001]. Homocysteine were lower in our hypertensives compared with controls [8.7(6.9-11.2) vs. 10.5(8.5-13.1) micromol/l, p=0.005], but there were significant correlations between homocysteine levels and both calculated 10-year coronary heart disease risk (Spearman r=0.197, p=0.026) and stroke risk (r=0.210, p=0.018), using the Framingham equation. There was a positive correlation between plasma homocysteine and soluble P-selectin (r=0.180, p=0.025), which persisted in multiple linear regression analysis. There was no significant relationship between homocysteine and HCT, PV, or the endothelial marker, vWF.

CONCLUSION

Hypertensives demonstrate abnormalities of endothelial, platelet and rheological function. Homocysteine is related to both 10-year coronary heart disease risk and stroke risk, and is significantly correlated with soluble P-selectin, a marker of platelet activation, in hypertensives but only weakly or not at all to other thrombotic markers. Increased platelet activation as reflected by soluble P-selectin may be one mechanism by which hyperhomocysteinaemia confers an increased thrombotic risk in hypertension.

Genetic influences on blood pressure within the Stanislas Cohort

OBJECTIVE

To investigate the association of 21 polymorphisms within 13 genes, APOE, APOB, APOC3, CETP, LPL, PON1, MTHFR, FGB, F5, GPIIIa, SELE, ACE and AGT, with inter-individual blood pressure (BP) variation.

PARTICIPANTS

Seven hundred and seventy-six men and 836 women, free of antihypertensive and lipid-lowering medications, were selected from the Stanislas Cohort.

RESULTS

ANOVA on blood pressure values after adjustment for covariates [age, body mass index (BMI), contraceptive pill, tobacco and alcohol] showed that lipoprotein lipase (LPL) Ser447Ter and glycoprotein IIIA (GpIIIa) Pl polymorphisms were significantly associated with BP in women (0.01 < or = P < or = 0.05), whereas BP levels in men were significantly different according to apolipoprotein CIII (APOC3) 3206T/G and -482C/T polymorphisms (P < or = 0.05). In women, compared to the most common allele, the GpIIIa Pl allele was associated with increased mean arterial pressure (MAP) (P < 0.05) and pulse pressure (PP) (P < 0.001), and the LPL 447Ter allele was associated with decreased systolic blood pressure (SBP) and PP levels (0.001 < or = P < or = 0.05). These two polymorphisms appeared to act independently. In men, the APOC3 3206GG genotype was related to decreased diastolic blood pressure (DBP) and MAP levels (P < or = 0.01), and the APOC3 -482T allele with decreased PP levels (P < or = 0.05). The presence of both the -482C allele and the 3206GG genotype was related to decreased DBP, suggesting that specific haplotypes might be involved.

CONCLUSION

The APOC3, LPL and GpIIIa genes were found to be associated with BP levels. The contributions of these genes, although modest, are consistent with the polygenic nature of BP levels.

Platelet and haemorheological markers in 'high risk' hypertensives are improved by tighter blood pressure control and cardiovascular risk management: a substudy of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT)

OBJECTIVE

To investigate the impact of intensified cardiovascular risk management on soluble markers of platelet, endothelial and rheological function in a population of middle-aged hypertensive patients at high risk of cardiovascular complications.

DESIGN

Prospective follow-up study.

SUBJECTS AND METHODS

A total of 159 hypertensive patients [138 male, mean age 64 (+/-8) years] and 80 healthy controls were studied. Plasma levels of soluble P-selectin (sP-sel, a marker of platelet function), von Willebrand factor (vWF, an index of endothelial damage/dysfunction) and rheological indices [fibrinogen (Fib), plasma viscosity (PV), haematocrit (HCT), white blood count (WBC) and platelet count] were measured at baseline and again (in the patients) after 6 months' treatment.

RESULTS

As expected, 6 months of intensified cardiovascular risk management resulted in a significant fall in mean blood pressure (BP) and total cholesterol. It also resulted in reduced haematocrit, vWF, sP-sel, WBC and PV levels (all P < 0.001), but not plasma fibrinogen. There were no correlations between the fall in BP and the improvement in any of the research indices.

CONCLUSIONS

Intensified cardiovascular risk management results in significant improvements in indices of endothelial, platelet and rheological function in a population of hypertensives at high risk of cardiovascular events. These improvements appear to be independent of the degree of change in BP. Given the fundamental role of interactions between the endothelium and circulating blood components in the pathogenesis of hypertensive complications this may be of importance in preventing adverse cardiovascular outcomes.

Von Willebrand factor, soluble P-selectin, and target organ damage in hypertension: a substudy of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT)

To investigate the relationship between soluble markers of platelet, endothelial and rheological function, and target organ damage and their response to intensified management in a population of middle-age hypertensive patients at high risk of cardiovascular complications, we studied 382 consecutive patients (308 men; mean age, 63 years, SD 8) along with 60 normotensive controls free of cardiovascular disease. Patients were divided into those with target organ damage (TOD; n=107) and those free of end-organ damage. Plasma levels of soluble P-selectin (sP-sel), a marker of platelet activation, and von Willebrand factor (vWF), an index of endothelial damage/dysfunction (both enzyme-linked immunosorbent assay), and the rheological indices fibrinogen, plasma viscosity, hematocrit, platelet, and white cell count were measured. In 53 patients, variables were further measured after 6 months of intensified cardiovascular risk management. Patients with TOD had significantly higher vWF, 137 (SD 33) versus 125 (SD 33) IU/dL (P=0.002,) and a greater proportion of smokers, 31% versus 16% (P=0.002). There were no statistically significant differences in plasma viscosity, fibrinogen, hematocrit, white blood cell count, platelet count, or sP-sel between the 2 subgroups. In multivariate analysis, vWF was a significant independent predictor for TOD. After 6 months of intensified management in 53 patients who entered the trial, there were significant reductions in systolic blood pressure, total cholesterol, hematocrit, plasma viscosity, sP-sel, and vWF (all P<0.01) but no significant change in fibrinogen. In conclusion, there is a relationship between TOD and endothelial damage/dysfunction in hypertension. Intensified management results in improvements in hemorheology, endothelial and platelet function.