Is hypertension a prothrombotic state?

Post-stroke cognitive impairment and brain hemorrhage are augmented in hypertensive mice

Hypertension is a major risk factor for both stroke and cognitive impairment, but it is unclear whether it may specifically affect post-stroke cognitive impairment. We assessed the effect of hypertension and/or stroke on brain injury, cognitive outcome, and the brain transcriptomic profile. C57BL/6J mice (n = 117; 3-5 mo.) received s.c. infusion of either saline or angiotensin II followed by sham surgery or photothrombotic stroke targeting the prefrontal cortex seven days later. Cognitive function was assessed with the Barnes maze and RNA sequencing was used to quantify transcriptomic changes in the brain. Angiotensin II treatment produced spontaneous hemorrhaging after stroke. In the Barnes maze, hypertensive mice that received stroke surgery had an increased escape latency compared to other groups (day 3: hypertensive + stroke = 166.6 ± 6.0 s vs. hypertensive + sham = 122.8 ± 13.8 s vs. normotensive + stroke = 139.9 ± 10.1 s vs. normotensive + sham = 101.9 ± 16.7 s), consistent with impaired cognition. RNA sequencing revealed >1500 differentially expressed genes related to neuroinflammation in hypertensive + stroke vs. normotensive + stroke, which included genes associated with apoptosis, microRNAs, autophagy, anti-cognitive biomarkers and Wnt signaling. Overall, we show that the combination of hypertension and stroke resulted in greater learning impairment and brain injury.

Daytime plasma cortisol and cortisol response to dexamethasone suppression are associated with a prothrombotic state in hypertension

Background and aims

A prothrombotic state was demonstrated in patients with Cushing's syndrome and is involved in the development and progression of cardiovascular and renal damage in hypertensive patients. This study was designed to examine the relationships between cortisol secretion and the hemostatic and fibrinolytic systems in hypertension.

Methods

In 149 middle-aged, nondiabetic, essential hypertensive patients free of cardiovascular and renal complications, we measured hemostatic markers that express the spontaneous activation of the coagulation and fibrinolytic systems and assessed daily cortisol levels (8 AM, 3 PM, 12 AM; area under the curve, AUC-cortisol) together with the cortisol response to dexamethasone overnight suppression (DST-cortisol).

Results

Plasma levels of D-dimer (D-dim), prothrombin fragment 1 + 2 (F1 + 2), and von Willebrand factor (vWF) were progressively and significantly higher across tertiles of AUC-cortisol and DST-cortisol, whereas no differences were observed in fibrinogen, tissue plasminogen activator, plasminogen activator inhibitor-1, antithrombin III, protein C, and protein S. D-dim, F1 + 2, and vWF were significantly and directly correlated with age and both AUC-cortisol and DST-cortisol. Multivariate regression analysis showed that both AUC-cortisol and DST-cortisol were related to plasma D-dim, F1 + 2, and vWF independently of age, body mass index, blood pressure, and renal function.

Conclusion

Greater daily cortisol profile and cortisol response to overnight suppression are independently associated with a prothrombotic state in hypertensive patients and might contribute to the development of organ damage and higher risk of cardiovascular complications.

Exercise testing unmasks exaggerated blood pressure independent of fibrinolytic response in Black but not White postmenopausal females

Exercise testing unmasks more exaggerated systolic blood pressure responses (SBP) in Black compared with White male adults. Such responses, if translatable to females, may detect racial disparities particularly relevant during menopause. Given the endothelial involvement in BP regulation and as a source of fibrinolytic markers, it follows that fibrinolytic and BP response to exercise could be linked. Thus, we examined BP and fibrinolytic responses to exercise testing in Black and White postmenopausal females. Postmenopausal females (Black = 40; White = 41; 51-70 yr) performed maximal treadmill exercise. BP and blood draws were conducted before and immediately after exercise. Plasma samples, using minimal stasis, were analyzed for tissue plasminogen activator (tPA) and plasminogen activator inhibitor 1 (PAI-1) activity and antigen, respectively. Resting SBP and fibrinolytic potential were similar between races. Black females exhibited greater increases in SBP during exercise [change (d)=75, 95% CI: 64-86 mmHg, P < 0.001] than White females (d = 60, 95% CI: 48-71 mmHg, P < 0.001). Black compared with White females had smaller changes in tPA (d = 3.27, 95% CI: 2.28-4.27 IU/mL, P < 0.001 vs. d = 5.55, 95% CI: 4.58-6.53, P < 0.001) and PAI-1 (d = -2.89, 95% CI: -4.39 to -1.40 IU/mL, P < 0.001 vs. d = -5.08, 95% CI: -6.59 to -3.61, P < 0.001) activities after exercise. SBP exercise-induced changes were not associated with tPA (r = -0.10, P = 0.42) or PAI-1 (r = 0.13, P = 0.30), without any influence of race (P > 0.05). Our findings show that maximal exercise unmasks risk factors for cardiovascular disease in Black postmenopausal females.NEW & NOTEWORTHY Exaggerated SBP responses to exercise testing are more frequent in Black than in White male adults. Such responses, if translatable to females, may detect early racial disparities arriving during menopause. Because the endothelium regulates BP and fibrinolytic responses, these could be linked during exercise. At peak exercise, Black but not White postmenopausal females had more exaggerated SPB responses regardless of reduced fibrinolytic potential. Maximal exercise unmasked risk factors for cardiovascular disease in Black postmenopausal females.

Predictors of aneurysmal occlusion following intracranial aneurysms treatment with pipeline embolization device

PURPOSE

Pipeline embolization device (PED) is thought to induce aneurysmal occlusion through diversion of flow away from the aneurysmal sac with subsequent thrombosis and endothelialization. The impact of different factors especially hypertension (HTN)-a known predisposing factor to hypercoagulability and altered endothelial function-on aneurysmal occlusion after flow diversion has not been studied. We sought to determine predictors of aneurysmal occlusion following PED treatment focusing on impact of blood pressure.

METHODS

Database of patients with cerebral aneurysms treated with PED from 2013 to 2019 at our institution was retrospectively reviewed. Patients were defined as hypertensive if (1) they had a documented history of HTN requiring anti-HTN medications or (2) average systolic blood pressure on three measurements was > 130 mmHg. The primary outcome was aneurysm occlusion status at the last imaging follow-up. Multivariable logistic regression model was constructed to assess the effect of HTN on occlusion, controlling for age, smoking, aneurysmal size, fusiform morphology, posterior circulation location, and incorporated branches.

RESULTS

A total of 331 aneurysms in 294 patients were identified for this analysis. The mean age was 59 years (79.9% female). Fifty-five percent of the cohort were classified as hypertensive. When controlling for other potential confounders, hypertensive patients trended toward higher odds of achieving complete occlusion compared to non-hypertensive patients (OR = 2.05; 95% CI = 0.99-4.25; p = 0.052). Meanwhile, age (OR = 0.91; 95% CI = 0.88-0.95; p < 0.001) and an incorporated branch into an aneurysm (OR = 0.22; 95% CI = 0.08-0.58; p < 0.002) were associated with decreased odds for complete aneurysmal occlusion.

CONCLUSION

Hypertensive patients show a trend toward higher odds of achieving complete occlusion when controlling for potential confounders. The HTN-induced hypercoagulable state, enhanced endothelial activation, and altered extracellular matrix regulation might be the contributing factors. Further research is warranted to explore clinical implications of these findings.

Association of arterial stiffness with a prothrombotic state in uncomplicated nondiabetic hypertensive patients

Background and aims

Past studies reported a significant contribution of a prothrombotic state to the development and progression of target organ damage in hypertensive patients. Stiffening of arterial vessels is associated with aging and hypertension, and additional factors could contribute to this process. This study was designed to examine the relationships between arterial stiffening and the hemostatic and fibrinolytic system.

Methods

In 128 middle-aged, nondiabetic, essential hypertensive patients without major cardiovascular and renal complications, we measured coagulation markers that express the spontaneous activation of the hemostatic and fibrinolytic system and assessed stiffness of the arterial tree by measurement of the carotid/femoral pulse wave velocity (cfPWV) and pulse wave analysis with calculation of the brachial augmentation index (AIx).

Results

Levels of fibrinogen (FBG), D-dimer (D-d), and plasminogen activator-inhibitor 1 (PAI-1) were significantly higher in patients with PWV and AIx above the median of the distribution. FBG, D-d, and PAI-1 were significantly and directly related with both cfPWV and AIx, and multivariate regression analysis indicated that the relationships of D-d and PAI-1 with both cfPWV and AIx and of FBG with AIx, were independent of age, body mass index, severity and duration of hypertension, use of antihypertensive drugs, blood glucose, and plasma lipids.

Conclusion

In middle-aged, uncomplicated, nondiabetic patients with essential hypertension, spontaneous activation of plasma hemostatic cascade and impaired fibrinolysis is significantly and independently associated with stiffening of the arterial tree.

Circulating platelet-derived extracellular vesicles correlate with night-time blood pressure and vascular organ damage and may represent an integrative biomarker of vascular health

Elevated office blood pressure (BP) has previously been associated with increased levels of circulating extracellular vesicles (EVs). The present study aimed to assess the relationship between levels of platelet derived EVs, ambulatory BP parameters, and pulse wave velocity as a marker of macrovascular organ damage. A total of 96 participants were included in the study. Platelet-derived extracellular vesicles (pEVs) were evaluated by flow cytometry (CD41+/Annexin v+). BP evaluation included unobserved automated office BP and ambulatory BP monitoring. Carotid-femoral pulse wave velocity (PWV) was measured as a marker of macrovascular damage. pEVs correlated with nocturnal systolic BP (r = 0.31; p = .003) and nocturnal dipping (r = -0.29; p = .01) in univariable analysis. Multivariable regression models confirmed robustness of the association of EVs and nocturnal blood pressure (p = .02). In contrast, systolic office, 24h- and daytime-BP did not show significant associations with pEVs. No correlations were found with diastolic BP. Circulating pEVs correlated with pulse wave velocity (r = 0.25; p = .02). When comparing different hypertensive phenotypes, higher levels of EVs and PWV were evident in patients with sustained hypertension compared to patients with white coat HTN and healthy persons. Circulating platelet derived EVs were associated with nocturnal BP, dipping, and PWV. Given that average nocturnal BP is the strongest predictor of CV events, platelet derived EVs may serve as an integrative marker of vascular health, a proposition that requires testing in prospective clinical trials.

Fibrin clot properties and fibrinolysis in patients with endocrine hypertension due to aldosterone or catecholamines excess

OBJECTIVE

The aim of the study was to investigate a new possible background of increased risk of cardiovascular events in two forms of endocrine hypertension: in primary aldosteronism (PA) and pheochromocytoma/paraganglioma (PPGL) in comparison to essential hypertension (EHT).

CONTEXT

Prothrombotic properties of the fibrin clot structure, impaired fibrinolysis and enhanced thrombin generation have been reported to be associated with increased cardiovascular risk.

DESIGN

Patients with PA and PPGL were evaluated at baseline and re-evaluated 3 months after causative treatment. At baseline PA and PPGL patients were compared to matched EHT patients and to healthy controls.

PATIENTS

The study included 35 patients with PA, 16 patients with PPGL and two reference groups of patients with EHT (32 and 22 patients) and healthy controls (35 and 23 subjects).

MEASUREMENTS

All subjects underwent evaluation according to the study protocol that included plasma fibrin clot permeability (Ks), clot lysis time, endogenous thrombin potential.

RESULTS

There were no differences in clot structure and fibrinolytic activity in PA and PPGL patients as compared to matched patients with EHT, whereas all hypertensive groups were characterized by more compact fibrin clot structure, faster clot formation and enhanced thrombin generation in comparison to healthy controls. Both in PA and PPGL patients, fibrin clot properties and fibrinolytic parameters remained stable after the causative treatment.

CONCLUSIONS

Patients with PA and PPGL are at a prothrombic state comparable to patients with EHT. The results suggest the higher risk of cardiovascular events observed in hypertensive PA and PPGL as compared to EHT is not mediated through investigated prothrombic mechanisms.

Effects of individualized administration of folic acid on prothrombotic state and vascular endothelial function with H-type hypertension: A double-blinded, randomized clinical cohort study

BACKGROUND

Hypertension and hyperhomocysteinemia (HHcy) have long been associated with adverse cardiovascular and cerebrovascular health outcomes. This study evaluated the effect of individualized administration of folic acid (FA) on homocysteine (Hcy) levels, prothrombotic state, and blood pressure (BP) in patients with H-type hypertension (combination of HHcy and hypertension).

METHODS

In this double-blinded, randomized clinical cohort study, 126 patients with H-type hypertension who were treated at our hospital were randomly divided into treatment and control groups (n = 55 each). The control group was treated with oral levamlodipine besylate tablets 2.5 mg and placebo, once a day (in the morning). The treatment group was first treated with oral levamlodipine besylate 2.5 mg and FA tablets 0.8 mg, once a day (in the morning), for 12 weeks. Then, in a second 12-week phase, the FA dose was adjusted using the methylene tetrahydrofolate reductase C677 polymorphism genotype. The levels of Hcy and coagulation factors, prothrombotic state parameters, BP, and adverse drug reactions were compared between the 2 groups.

RESULTS

Pretreatment general patient characteristics, including Hcy levels, were similar between the 2 groups (P > .05). BP and prothrombotic status did not differ before and after the first phase of treatment (P > .05). However, Hcy and endothelin-1 (ET-1) levels decreased, while nitric oxide levels increased significantly in the intervention group (P < .05). In the second phase, after 3 months' treatment with an FA dose adjusted according to methylene tetrahydrofolate reductase C677T genotype, the Hcy and ET-1/NO levels were significantly decreased in the intervention group and were lower than those after the first treatment phase and lower than in the control group (P < .01). BP, D-dimer levels, and fibrinogen scores were significantly lower after the second treatment phase (P < .01). There was no significant difference in the incidence of adverse drug reactions between the 2 groups (P > .05).

CONCLUSIONS

Individualized administration of FA tablets can effectively reduce BP, and Hcy and coagulation factor levels, and significantly improve prothrombotic status in patients with H-type hypertension.

Clinical Management of Hypertension, Inflammation and Thrombosis in Hospitalized COVID-19 Patients: Impact on Survival and Concerns

The most severe clinical manifestations of the Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are due to an unbalanced immune response and a pro-thrombotic hemostatic disturbance, with arterial hypertension or diabetes as acknowledged risk factors. While waiting for a specific treatment, the clinical management of hospitalized patients is still a matter of debate, and the effectiveness of treatments to manage clinical manifestations and comorbidities has been questioned. In this study, we aim to assess the impact of the clinical management of arterial hypertension, inflammation and thrombosis on the survival of COVID-19 patients. The Spanish cohorts included in this observational retrospective study are from HM Hospitales (2035 patients) and from Hospital Universitario Central de Asturias (72 patients). Kaplan Meier survival curves, Cox regression and propensity score matching analyses were employed, considering demographic variables, comorbidities and treatment arms (when opportune) as covariates. The management of arterial hypertension with angiotensin-converting enzyme 2 (ACE2) inhibitors or angiotensin receptor blockers is not detrimental, as was initially reported, and neither was the use of non-steroidal anti-inflammatory drugs (NSAIDs). On the contrary, our analysis shows that the use on itself of corticosteroids is not beneficial. Importantly, the management of COVID-19 patients with low molecular weight heparin (LMWH) as an anticoagulant significantly improves the survival of hospitalized patients. These results delineate the current treatment options under debate, supporting the effectiveness of thrombosis prophylaxis on COVID-19 patients as a first-line treatment without the need for compromising the treatment of comorbidities, while suggesting cautiousness when administering corticosteroids.

The association between mean platelet volume and inflammation in geriatric patients with emergency hypertension

Objectives

We aimed to investigate the role of inflammation parameters and platelet activation in geriatric patients with hypertension. Therefore, we compared the levels of those parameters in patients with hypertensive urgency and emergency. We also investigated the potential relationship between those parameters.

Methods

Ninety-six hypertensive (HT) patients (aged > 60) were included in the study in two groups: HT emergency (N = 48, group 1) and HT urgency (N = 48, group 2). Mean platelet volume (MPV), neutrophil-to-lymphocyte ratio (NLR) and high-sensitive C reactive protein (hs-CRP) were compared between those groups. Optimum cut-off levels of each parameter were determined by the use of Receiver operating characteristic (ROC) curve analysis. Pearson correlation test was used to examine the relationship between variables.

Results

The mean MPV and hs-CRP levels were significantly higher in patients with HT emergencies (both P < 0.001). Mean NLR was also significantly different between the two groups (P = 0.011). Pearson correlation analysis revealed a positive but weak correlation between the MPV and NLR (r = 0.245, P = 0.016), the hs-CRP level (r = 0.394, P < 0.001), and the WBC count (r = 0.362, P < 0.001).

Conclusion

Increased platelet activity and inflammation are associated with the end organ failure. Levels of MPV and other inflammatory parameters may be useful in the management of geriatric patients with HT.

Association of ambulatory arterial stiffness index with sEPCR in newly diagnosed hypertensive patients

AIM

Increased arterial stiffness is strongly associated with cardiovascular diseases, while thrombotic events are more common than hemorrhagic events in hypertensive patients. Markers of a hypercoagulable state may also predict future cardiovascular events in hypertensive patients. Here, we speculated that increased arterial stiffness might lead to the development of a hypercoagulable state that can play a role in the thrombotic complications of hypertension. Soluble endothelial protein C receptor (sEPCR) is one such marker of hypercoagulation. The ambulatory arterial stiffness index (AASI) could be accepted as a non-invasive measure of arterial stiffness. The aim of this study was to investigate association of AASI with levels of sEPCR in newly diagnosed hypertensive patients.

MATERIALS AND METHODS

The study included 263 newly diagnosed essential hypertensive patients and 55 healthy normotensive controls. All subjects underwent 24 h ambulatory blood pressure monitoring (ABPM); the AASI was derived from ABPM tracings. Plasma sEPCR was measured by ELISA.

RESULTS

Hypertensive patients (n = 263) had higher AASI, C-reactive protein (CRP) and sEPCR versus the normotensive healthy group (n = 55). Univariate analysis showed that AASI was positively associated with age (r = 0.212, p <  0.001) body mass index (r = 0.412, p < 0.001), pulse pressure (r = 0.350, p < 0.001), plasma sEPCR (r = 0.894, p < 0.001), 24-h heart rate (r = 0.176, p = 0.001) and inversely related to high-density lipoprotein (HDL) (r = -0.293, p < 0.001). Multivariate analyses revealed that sEPCR and HDL are independently correlated to AASI.

CONCLUSION

We suggest that increased AASI is associated with elevated sEPCR. It might be responsible for subsequent thrombotic events in newly diagnosed hypertensive patients.

Relationship between mean platelet volume and morning blood pressure surge in newly diagnosed hypertensive patients

OBJECTIVE

Morning blood pressure surge (MBPS) is an independent predictor of atherothrombotic cardiovascular events in hypertensive patients. There is evidence from studies supporting the validity of mean platelet volume (MPV) as a marker of vascular risk and predictor of thrombotic complications. The aim of this study is to investigate the relationship between MPV and MBPS in hypertensive patients.

METHODS

Measurements were obtained from 298 patients with newly diagnosed essential hypertension (Mean age: 51.9 ± 11.7 years). The patients were divided into two groups (MPV(low) group; <10.8 fL, MPV(high) group; ≥ 10.8 fL). The MBPS was calculated as mean systolic BP during the 2 hours after awaking minus the mean systolic BP during the 1 hour that included the lowest sleep BP.

RESULTS

MPV was independently associated with MBPS (β=0.554, p<0.001) and hs-CRP level (β=0.286, p<0.001).

CONCLUSION

Finally, higher MPV values related to enhanced MBPS which are associated with atherothrombotic cardiovascular events.

Tissue factor, protease activated receptors and pathologic heart remodelling

Tissue factor is the primary initiator of coagulation cascade and plays an essential role in haemostasis and thrombosis. In addition, tissue factor and coagulation proteases contribute to many cellular responses via activation of protease activated receptors. The heart is an organ with high levels of constitutive tissue factor expression. This review focuses on the role of tissue factor, coagulation proteases and protease activated receptors in heart haemostasis and the pathological heart remodelling associated with myocardial infarction, viral myocarditis and hypertension.

PPARγ ligands decrease hydrostatic pressure-induced platelet aggregation and proinflammatory activity

Hypertension is known to be associated with platelet overactivity, but the direct effects of hydrostatic pressure on platelet function remain unclear. The present study sought to investigate whether elevated hydrostatic pressure is responsible for platelet activation and to address the potential role of peroxisome proliferator-activated receptor-γ (PPARγ). We observed that hypertensive patients had significantly higher platelet volume and rate of ADP-induced platelets aggregation compared to the controls. In vitro, Primary human platelets were cultured under standard (0 mmHg) or increased (120, 180, 240 mmHg) hydrostatic pressure for 18 h. Exposure to elevated pressure was associated with morphological changes in platelets. Platelet aggregation and PAC-1 (the active confirmation of GPIIb/IIIa) binding were increased, CD40L was translocated from cytoplasm to the surface of platelet and soluble CD40L (sCD40L) was released into the medium in response to elevated hydrostatic pressure (180 and 240 mmHg). The PPARγ activity was up-regulated as the pressure was increased from 120 mmHg to 180 mmHg. Pressure-induced platelet aggregation, PAC-1 binding, and translocation and release of CD40L were all attenuated by the PPARγ agonist Thiazolidinediones (TZDs). These results demonstrate that platelet activation and aggregation are increased by exposure to elevated pressure and that PPARγ may modulate platelet activation induced by high hydrostatic pressure.

Mean platelet volume and abnormal left ventricle geometric patterns in patients with untreated essential hypertension

Abnormal left ventricle (LV) geometric patterns are associated with a greater risk of hypertensive vascular complications. The mean platelet volume (MPV) reflects the platelet activity, and is associated with overall vascular mortality. Although association between MPV and LV hypertrophy in hypertensive patients has been investigated, relation between abnormal LV geometric patterns and MPV was not studied so far. The aim of this study is to investigate the relationship between MPV and abnormal LV geometric patterns in hypertensive patients. Measurements were obtained from 223 patients with untreated essential hypertension (Mean age = 52.1 ± 5.2 years). Four different geometric patterns (NG; normal geometry, CR; concentric remodelling, EH; eccentric hypertrophy, CH; concentric hypertrophy) were determined according to the LV mass index (LVMI) and relative wall thickness (RWth). MPV, high sensitive C-reactive protein (hsCRP) and other biochemical markers were measured in all patients. The highest MPV values were determined in CH group compared with NG, CR and EH groups (p < 0.05, for all). MPV values were similar among the NG, CR and EH groups (p > 0.05, for all). MPV was associated with age, glucose, hsCRP, RWth, LVMI and LV geometry in bivariate analysis (p < 0.05, for all). Age (β = 0.110, p = 0.033), LVMI (β = 0.471, p < 0.001) and hsCRP (β = 0.525, p < 0.001) were independent predictors of high MPV in multiple linear regression analysis. The highest MPV values were observed in the CH group. This result may be associated with increased inflammation and LV hypertrophy in this geometric pattern.

HIV status, burden of comorbid disease, and biomarkers of inflammation, altered coagulation, and monocyte activation

BACKGROUND

Biomarkers of inflammation, altered coagulation, and monocyte activation are associated with mortality and cardiovascular disease (CVD) in the general population and among human immunodeficiency virus (HIV)-infected people. We compared biomarkers for inflammation, altered coagulation, and monocyte activation between HIV-infected and uninfected people in the Veterans Aging Cohort Study (VACS).

METHODS

Biomarkers of inflammation (interleukin-6 [IL-6]), altered coagulation (d-dimer), and monocyte activation (soluble CD14 [sCD14]) were measured in blood samples from 1525 HIV-infected and 843 uninfected VACS participants. Logistic regression was used to determine the association between HIV infection and prevalence of elevated (>75th percentile) biomarkers, adjusting for confounding comorbidities.

RESULTS

HIV-infected veterans had less prevalent CVD, hypertension, diabetes, obesity, hazardous drinking, and renal disease, but more dyslipidemia, hepatitis C, and current smoking than uninfected veterans. Compared to uninfected veterans, HIV-infected veterans with HIV-1 RNA ≥500 copies/mL or CD4 count <200 cells/µL had a significantly higher prevalence of elevated IL-6 (odds ratio [OR], 1.54; 95% confidence interval [CI],1.14-2.09; OR, 2.25; 95% CI, 1.60-3.16, respectively) and d-dimer (OR, 1.97; 95% CI, 1.44-2.71, OR, 1.68; 95% CI, 1.22-2.32, respectively) after adjusting for comorbidities. HIV-infected veterans with a CD4 cell count <200 cells/µL had significantly higher prevalence of elevated sCD14 compared to uninfected veterans (OR, 2.60; 95% CI, 1.64-4.14). These associations still persisted after restricting the analysis to veterans without known confounding comorbid conditions.

CONCLUSIONS

These data suggest that ongoing HIV replication and immune depletion significantly contribute to increased prevalence of elevated biomarkers of inflammation, altered coagulation, and monocyte activation. This contribution is independent of and in addition to the substantial contribution from comorbid conditions.

Brain injury after intracerebral hemorrhage in spontaneously hypertensive rats

OBJECT

Hypertension is the main cause of spontaneous intracerebral hemorrhages (ICHs), but the effects of hypertension on ICH-induced brain injury have not been well studied. In this study, the authors examined ICH-induced brain injury in spontaneously hypertensive rats (SHRs).

METHODS

This 2-part study was performed in 12-week-old male SHRs and Wistar Kyoto (WKY) rats. First, the rats received an intracaudate injection of 0.3 U collagenase, and hematoma sizes were determined at 24 hours. Second, rats were injected with 100 μl autologous whole blood into the right basal ganglia. Brain edema, neuronal death, ferritin expression, microglia activation, and neurological deficits were examined.

RESULTS

Hematoma sizes were the same in SHR and WKY rats 24 hours after collagenase injection. The SHRs had greater neuronal death and neurological deficits after blood injection. Intracerebral hemorrhage also resulted in higher brain ferritin levels and stronger activation of microglia in SHRs. However, perihematomal brain edema was the same in the SHRs and WKY rats.

CONCLUSIONS

Moderate chronic hypertension resulted in more severe ICH-induced neuronal death and neurological deficits, but did not exaggerate hematoma enlargement and perihematomal brain edema in the rat ICH models.

A clinical cardiology perspective of thrombophilias

Thrombophilias, an inherited and/or acquired predisposition to vascular thrombosis beyond hemostatic needs are common in cardiovascular medicine and include systemic disorders such as coronary atherosclerosis, atrial fibrillation, exogenous obesity, metabolic syndrome, collagen vascular disease, human immunodeficiency virus, blood replacement therapy and several commonly used medications. A contemporary approach to patients with suspected thrombophilias, in addition to a very selective investigation for gain-of-function and loss-of-function gene mutations affecting thromboresistance, must consider prevalent diseases and management decisions encountered regularly by cardiologists in clinical practice. An appropriate recognition of common disease states as thrombophilias will also stimulate platforms for much needed scientific investigation.

Effects of serum homocysteine and adiponectin levels on platelet aggregation in untreated patients with essential hypertension

The aim of the present study is to determine and correlate adiponectin, homocysteine, nitric oxide, and ADP-induced platelet aggregation levels in untreated patients with essential hypertension and healthy individuals. A total of 36 individuals, 23 untreated patients with essential hypertension and 13 healthy individuals, were included in the scope of this study. Enzyme-linked immunosorbent assay (ELISA) was used to determine the serum adiponectin and TNF-alpha levels. The levels of serum homocysteine were measured by using competitive chemiluminescent enzyme immunoassay. Serum concentrations of hsCRP were measured by the Nephelometer. Plasma nitrite, nitrate, and total nitric oxide (NOx) levels were determined by colorimetric method. Homocysteine and hsCRP levels in patients with essential hypertension were found to be significantly higher than those in the control group (P = 0.02, P = 0.001, respectively). The average platelet aggregation levels in patient group were higher than control group, but there were no statistically significant differences between them (P > 0.05). In addition, in patients with essential hypertension adiponectin and nitrite levels are significantly lower than control group (P < 0.001, P = 0.045, respectively). We have also found significant correlations between nitrite-platelet aggregation amplitude, nitrite-platelet aggregation slope, nitrite-adiponectin, homocysteine-platelet aggregation amplitude, and sistolic blood pressure-platelet aggregation amplitude levels (r = -0.844; P < 0.001, r = -0.680; P = 0.011, r = 0.454; P = 0.05, r = 0.414; P = 0.05, r = 0.442; P = 0.035, respectively). Increased homocysteine and decreased adiponectin serum levels in patients with essential hypertension correlate well with changes in ADP-induced conventional platelet aggregation. This association may potentially contribute to future thrombus formation and higher risks for cardiovascular events in hypertensive patients.

Procoagulant stress reactivity and recovery in apparently healthy men with systolic and diastolic hypertension

OBJECTIVE

The aim of this study was to investigate whether systemic systolic hypertension (SHT) and diastolic hypertension (DHT) are associated with an exaggerated response of factor VII clotting activity (FVII:C), factor VIII clotting activity (FVIII:C), fibrinogen, and d-dimer to acute psychosocial stress.

METHODS

We performed the 15-min Trier Social Stress Test (i.e., combination of task preparation, job interview and mental arithmetic) in a sample of 42 middle-aged apparently healthy and unmedicated men with normal and elevated blood pressure (BP) (i.e. screening systolic and/or diastolic BP>or=130/85 mmHg). Blood samples for coagulation measures were obtained immediately pre and post stress and 20 min and 60 min thereafter. Repeated measures analyses of covariance controlled for age, body mass index, screening mean arterial BP, and resting level of coagulation factors.

RESULTS

There was a stress-by-DHT interaction for changes across all time points in FVII:C (P=.027), FVIII:C (P=.018), and d-dimer (P=.011) explaining between 14% and 17% of the variance. Compared to subjects without DHT, diastolic hypertensives had higher FVII:C immediately post stress (P=.085, Cohen's d=.60) and at 20-min recovery (P=.19, d=.46), higher FVIII:C at 20- (P=.028, d=.78) and at 60-min (P=.035, d=.75) recovery, and higher D-dimer at 20-min recovery (P=.10, d=.58). A significant stress-by-SHT interaction for fibrinogen (P=.050) became nonsignificant when controlling for covariates.

CONCLUSION

Diastolic hypertension exaggerated the acute procoagulant response to stress in middle-aged men. This effect was particularly observed during recovery of hypercoagulability from stress. The findings suggest a psychobiological mechanism linking stress with an increased atherothrombotic risk in hypertensive individuals.

Effects of blood pressure on the prothrombotic risk in 1235 patients with non-valvular atrial fibrillation

BACKGROUND

Increased levels of plasma von Willebrand factor (vWf, an index of endothelial damage/dysfunction) and soluble P-selectin (sP-sel, an index of platelet activation) concentrations have been reported as indices of the prothrombotic state in both non-valvular atrial fibrillation and hypertension separately. However, the effect of hypertension on the levels of these indices in the setting of atrial fibrillation, and whether increasing severity of hypertension presents an additive prothrombotic risk, is unclear.

METHODS

Plasma concentrations of vWf and sP-sel were measured by ELISA in 1235 patients with atrial fibrillation, and levels related to a history of hypertension and rising quartiles of systolic, diastolic and pulse pressure in those with and without diabetes mellitus and prior vascular events.

RESULTS

Mean plasma vWf was higher among patients with atrial fibrillation with a history of hypertension (149 vs 145 IU/dl, p = 0.005). Also, an increase in the levels of vWf with increasing quartiles of pulse pressure (p = 0.042) was noticed. However, on multivariate analysis, after adjusting for potential confounders, the effects of both hypertension and pulse pressure became non-significant (p = 0.261 and p = 0.5, respectively). Levels of sP-sel were unaffected by a history of hypertension and rising quartiles of systolic and diastolic blood pressure, or pulse pressure.

CONCLUSION

Among patients with atrial fibrillation, patients with hypertension have higher vWf levels, indicating endothelial damage/dysfunction, which is associated with increasing pulse pressure. However, these associations are probably owing to the presence of other associated cardiovascular disease, rather than hypertension itself. Furthermore, platelet activation (sP-sel) was unrelated to hypertension or blood pressure in this atrial fibrillation cohort. Hypertension or blood pressure levels do not seem to have an independent additive affect on the prothrombotic state in atrial fibrillation.

The role of stress hormones in the relationship between resting blood pressure and coagulation activity

BACKGROUND

Systemic hypertension confers a hypercoagulable state. We hypothesized that resting mean blood pressure (MBP) interacts with stress hormones in predicting coagulation activity at rest and with acute mental stress.

METHODS

We measured plasma clotting factor VII activity (FVII:C), FVIII:C, fibrinogen, D-dimer, epinephrine and norepinephrine, and saliva cortisol in 42 otherwise healthy normotensive and hypertensive medication-free men (mean age 43 +/- 14 years) at rest, immediately after stress, and twice during 60 min of recovery from stress.

RESULTS

At rest, the MBP-by-epinephrine interaction predicted FVII:C (beta = -0.33, P < 0.04) and D-dimer (beta = 0.26, P < 0.05), and the MBP-by-cortisol interaction predicted D-dimer (beta = 0.43, P = 0.001), all independent of age and body mass index (BMI). Resting norepinephrine predicted fibrinogen (beta = 0.42, P < 0.01) and D-dimer (beta = 0.37, P < 0.03), both independent of MBP. MBP predicted FVIII:C change from rest to immediately post-stress independent of epinephrine (beta = -0.37, P < 0.03) and norepinephrine (beta = -0.38, P < 0.02). Cortisol change predicted FVIII:C change (beta = -0.30, P < 0.05) independent of age, BMI and MBP. Integrated norepinephrine change from rest to recovery (area under the curve, AUC) predicted D-dimer AUC (beta = 0.34, P = 0.04) independent of MBP. The MBP-by-epinephrine AUC interaction predicted FVII:C AUC (beta = 0.28) and fibrinogen AUC (beta = -0.30), and the MBP-by-norepinephrine AUC interaction predicted FVIII:C AUC (beta = -0.28), all with borderline significance (Ps < 0.09) and independent of age and BMI.

CONCLUSIONS

MBP significantly altered the association between stress hormones and coagulation activity at rest and, with borderline significance, across the entire stress and recovery interval. Independent of MBP, catecholamines were associated with procoagulant effects and cortisol reactivity dampened the acute procoagulant stress response.