Strokes and their relationship to hypertension

The link between Alzheimer's disease and stroke: A detrimental synergism

Being age-related disorders, both Alzheimer's disease (AD) and stroke share multiple risk factors, such as hypertension, smoking, diabetes, and apolipoprotein E (APOE) Ɛ4 genotype, and coexist in patients. Accumulation of amyloid-β plaques and neurofibrillary tangled impair cognitive potential, leading to AD. Blocked blood flow in the neuronal tissues, causes neurodegeneration and cell death in stroke. AD is commonly characterized by cerebral amyloid angiopathy, which significantly elevates the risk of hemorrhagic stroke. Patients with AD and stroke have been both reported to exhibit greater cognitive impairment, followed by multiple pathophysiological mechanisms shared between the two. The manuscript aims to elucidate the relationship between AD and stroke, as well as the common pathways and risk factors while understanding the preventive therapies that might limit the negative impacts of this correlation, with diagnostic modalities and current AD treatments. The authors provide a comprehensive review of the link and aid the healthcare professionals to identify suitable targets and risk factors, that may retard cognitive decline and neurodegeneration in patients. However, more intricate research is required in this regard and an interdisciplinary approach that would target both the vascular and neurodegenerative factors would improve the quality of life in AD patients.

Evaluation of stroke in pregnant and non-pregnant women of reproductive years: A multicenter ambispective cohort study in a low- to middle-income country

Objective

Early recognition of stroke symptoms and risk factors is important for timely intervention to improve outcomes. This study aimed to investigate differences in stroke frequency, risk factors, and presentation in pregnant and non-pregnant women of reproductive years.

Methods

This multicenter ambispective cohort study, conducted from 4th August 2021 to 4th March 2023, examined strokes in women of reproductive years at the neurology outpatient/emergency department of five busiest/referred neuro-medical facilities in Karachi, Pakistan, where patients from across the nation are assessed. In all, 1210 patients were enrolled via consecutive or convenient sampling retrospectively from January 2017 to August 2021 and prospectively from August 2021 to March 2023. Pregnancy-related and non-pregnancy-related stroke occurrence and characteristics were compared using the chi-square/Fischer's exact test.

Results

56% were non-pregnancy-related strokes and 44% were pregnancy-related strokes with non-pregnancy-related strokes approximately equal throughout the reproductive years (15-24 years = 34%, 25-34 years = 25%, 35-45 years = 41%) and pregnancy-related stroke between 15 and 35 years (82%). In the non-pregnancy-related stroke, arterial stroke dominated (96.4%); while in pregnancy-related stroke, arterial stroke accounted for 61.4% and venous stroke for 38.6% of cases. Middle cerebral artery was a typical stroke site (66%). Infarction was the most significant CT/MRI finding (PRS = 89%, NPRS = 66%), with pregnancy-related stroke hemorrhagic stroke occurring in only 11% of cases and non-pregnancy-related stroke comprising one-third (34%). The most prevalent etiologies were eclampsia in pregnancy-related stroke (32%), hypertension in non-pregnancy-related stroke (40%), and cardiac problems among both groups (25%:33%). Weakness and headache were the common clinical manifestations among both groups. In the pregnancy-related and non-pregnancy-related stroke groups, the initial presentation of stroke resulted in severe disability for 91% and 75%, respectively. With timely treatment, the outcome improved significantly. The mortality rate was 7% for the pregnancy-related stroke group and 4% for the non-pregnancy-related stroke group.

Conclusions

Our findings show that stroke is prevalent among reproductive-year women, posing a significant mortality risk if not adequately recognized and treated. Awareness, research, and screening of stroke risk factors and their often-overlooked early presentation (i.e., headache and weakness) in reproductive years are essential to reducing stroke occurrence among reproductive-year women.

Effects of calcium channel blockers on perioperative ischemic events in hypertensive patients with intracranial aneurysms undergoing neurointervention

BACKGROUND

Although calcium channel blockers (CCBs) are useful in stroke prevention, their specific role in preventing stroke in hypertensive patients with intracranial aneurysms undergoing endovascular stent placement remains unclear.

METHODS

We retrospectively examined 458 hypertensive patients with intracranial aneurysms who underwent stent treatment, drawn from a larger multicenter cohort comprising 1326 patients across eight centers. Patients were dichotomized into two groups according to use of a CCB. Propensity score matching (PSM) was performed to balance group differences in patient and aneurysm characteristics. We conducted a comparison of patient and aneurysm characteristics, ischemic complications, and clinical outcomes between the two groups.

RESULTS

The CCB and non-CCB groups comprised 279 and 179 patients, respectively. PSM resulted in 165 matched pairs. After PSM, the incidence of ischemic events within 1 month of the procedure (4.2% vs 10.9%; P=0.022) and proportion of patients with modified Rankin Scale score >2 at last follow-up (1.5% vs 7.8%; P=0.013) were significantly lower in the CCB group. Among patients treated with combination therapy, inclusion of a CCB was associated with a lower incidence of ischemic events (1.5% vs 13.3%; P=0.345), but the difference was not statistically significant after correction.

CONCLUSIONS

CCB use in hypertensive patients undergoing endovascular stenting for treatment of intracranial aneurysms is associated with a lower incidence of ischemic events and a lower incidence of unfavorable neurological outcomes, especially when used in combination therapy.

Spontaneous abdominal wall blood vessel rupture as a rare complication of severe pre-eclampsia

This study describes a rare case of a prenatal spontaneous abdominal wall hematoma that occurred in a pregnant woman with severe pre‐eclampsia and upper respiratory tract infection.

Association of neck circumference and hypertension among adults in a rural community Thailand: A cross-sectional study

Introduction

Hypertension (HT) is a major non-communicable disease worldwide and a growing global public health problem. Although several studies have investigated the independent associations of neck circumference (NC) and hypertension, no such studies have been conducted among the Thai population.

Aim

This study aims to identify risk factors associated with hypertension, which may be used to predict HT among asymptomatic adults residing in a remote rural community in central Thailand.

Method

1,084 adults were included in this community-based cross-sectional study by a population-based total survey. The participants were included those who had been living in 6 villages in the rural community in the central area of Thailand. Anthropometric information, NC, body composition indexes such as waist circumference and blood pressure were measured. Logistic regression models were fitted to calculate the multi-variable adjusted prevalence and the association of NC with HT.

Result

The prevalence of HT among adults in the rural community was 27.7% (95% CI: 25.0–30.3). Of the 300 adults with HT, 164 participants (54.7%) were found within the unawareness HT category. We found that associated factors with HT were included larger neck circumference both continuous and categorical (≥ 37.5 in male, ≥ 32.5 in female), pre-existing diabetes mellitus, male, and higher body mass index.

Conclusion

Almost one-third of participants in the remote rural areas presented hypertension. NC was associated with HT independent from other risk factors. NC is a simple and useful anthropometric index to identify HT in rural Thai adults.

Vasa Vasorum Lumen Narrowing in Brain Vascular Hyalinosis in Systemic Hypertension Patients Who Died of Ischemic Stroke

Ischemic stroke is a major cause of death among patients with systemic hypertension. The narrowing of the lumen of the brain vasculature contributes to the increased incidence of stroke. While hyalinosis represents the major pathological lesions contributing to vascular lumen narrowing and stroke, the pathogenic mechanism of brain vascular hyalinosis has not been well characterized. Thus, the present study examined the postmortem brain vasculature of human patients who died of ischemic stroke due to systemic hypertension. Hematoxylin and eosin staining and immunohistochemistry showed the occurrence of brain vascular hyalinosis with infiltrated plasma proteins along with the narrowing of the vasa vasorum and oxidative stress. Transmission electron microscopy revealed endothelial cell bulge protrusion into the vasa vasorum lumen and the occurrence of endocytosis in the vasa vasorum endothelium. The treatment of cultured microvascular endothelial cells with adrenaline also promoted the formation of the bulge as well as endocytic vesicles. The siRNA knockdown of sortin nexin-9 (a mediator of clathrin-mediated endocytosis) inhibited adrenaline-induced endothelial cell bulge formation. Adrenaline promoted protein-protein interactions between sortin nexin-9 and neural Wiskott–Aldrich syndrome protein (a regulator of actin polymerization). Spontaneously hypertensive stroke-prone rats also exhibited lesions indicative of brain vascular hyalinosis, the endothelial cell protrusion into the lumen of the vasa vasorum, and endocytosis in vasa vasorum endothelial cells. We propose that endocytosis-dependent endothelial cell bulge protrusion narrows the vasa vasorum, resulting in ischemic oxidative damage to cerebral vessels, the formation of hyalinosis, the occurrence of ischemic stroke, and death in systemic hypertension patients.

Stroke, Vascular Dementia, and Alzheimer's Disease: Molecular Links

Stroke is a brain disease that occurs when blood flow stops, resulting in reduced oxygen supply to neurons. Stroke occurs at any time and at any age, but increases after the age of 55. It is the second leading cause of death and the third leading cause of disability-adjusted, life-years. The pathophysiology of ischemic stroke is complex and recent molecular, cellular, and animal models and postmortem brain studies have revealed that multiple cellular changes have been implicated, including oxidative stress/mitochondrial dysfunction, inflammatory responses, micro RNA alterations, and marked changes in brain proteins. These cellular changes provide new information for developing therapeutic strategies for ischemic stroke treatment. Research also revealed that stroke increases with a number of modifiable factors and most strokes can be prevented and/or controlled through pharmacological or surgical interventions and lifestyle changes. Ischemic stroke is the major risk factor for vascular dementia and Alzheimer's disease. This review summarizes the latest research findings on stroke, including causal factors and molecular links between stroke and vascular disease/Alzheimer's disease.

Common variants of ROCKs and the risk of hypertension, and stroke: Two case-control studies and a follow-up study in Chinese Han population

The Rho kinases (ROCKs) are recognized as a critical regulator of vascular functions in cardiovascular disorders. It is crucial to illustrate the association of ROCKs genetic variation and hypertension and/or stroke events. Herein we aimed at investigating the association of ROCK1 and ROCK2 with hypertension and stroke in Chinese Han population. Seven tagSNPs at ROCK1 and ROCK2 were genotyped in a community-based case-control study consisting of 2012 hypertension cases and 2210 normotensive controls and 4128 subjects were further followed up. In stroke case-control study, 1471 ischemic stroke (IS) inpatients and 607 hemorrhagic stroke (HS) inpatients were collected, and 2443 age-matched controls were selected from the follow-up population. Risks were estimated as odds ratio (OR) and hazard ratio (HR) by logistic and Cox regression. The community-based case-control study didn't identify any significant tagSNPs associated with hypertension even after adjustment for covariates. The follow-up analysis showed that rs1481280 of ROCK1 significantly associated with incident hypertension (HR=1.130, P=0.048) after adjusting for covariates. rs7589629 and rs978906 of ROCK2 were significantly associated with incident IS (HR=1.373, P=0.004; HR=1.284, P=0.026) respectively. In stroke case-control study, rs288980, rs1481280 and rs7237677 were significantly associated with IS and the adjusted ORs (P values) of additive model were 0.879 (0.010), 0.895 (0.036) and 0.857 (0.002) respectively. Furthermore, rs288980, rs7237677 and rs978906 were significantly associated with HS and the adjusted ORs (P values) of additive model were 0.857 (0.025), 0.848 (0.018) and 0.856 (0.027) respectively. Our findings suggest that ROCK1 and ROCK2 contribute to the genetic susceptibility of hypertension and stroke.

Molecular Links and Biomarkers of Stroke, Vascular Dementia, and Alzheimer's Disease

Stroke is a very common neurological disease, and it occurs when the blood supply to part of the brain is interrupted and the subsequent shortage of oxygen and nutrients causes damage to the brain tissue. Stroke is the second leading cause of death and the third leading cause of disability-adjusted life years. The occurrence of stroke increases with age, but anyone at any age can suffer a stroke. Stroke can be broadly classified in two major clinical types: ischemic stroke (IS) and hemorrhagic stroke. Research also revealed that stroke, vascular dementia (VaD), and Alzheimer's disease (AD) increase with a number of modifiable factors, and most strokes can be prevented and/or controlled through pharmacological or surgical interventions and lifestyle changes. The pathophysiology of stroke, VaD, and AD is complex, and recent molecular and postmortem brain studies have revealed that multiple cellular changes have been implicated, including inflammatory responses, microRNA alterations, and marked changes in brain proteins. These molecular and cellular changes provide new information for developing therapeutic strategies for stroke and related vascular disorders treatment. IS is the major risk factor for VaD and AD. This chapter summarizes the (1) links among stroke-VaD-AD; (2) updates the latest developments of research in identifying protein biomarkers in peripheral and central nervous system tissues; and (3) critically evaluates miRNA profile and function in human blood samples, animal, and postmortem brains.

Plasma thrombomodulin, fibrinogen, and activity of tissue factor as risk factors for acute cerebral infarction

Several studies have indicated association between hematologic markers and increased risks of cerebrovascular disease, but few reports referred to their roles together. We studied plasma levels of 16 hematologic markers in 50 cases diagnosed as acute cerebral infarction (ACI) and 54 hospital control subjects. Plasma levels of thrombomodulin, fibrinogen, and activity of tissue factor (aTF) were significantly higher in cases than in control subjects (P < .001, P < .01, and P < .05, respectively). Multivariate logistic regression analysis showed that hypertension and high plasma levels of thrombomodulin, fibrinogen, and aTF were significantly associated with presence of ACI (odds ratio [OR], 143.74, P < .001; OR, 2.05, P < .05; OR, 2.09, P < .05; OR, 1.02, P < .05, respectively). Our findings indicate that hypertension and elevation of plasma thrombomodulin, fibrinogen, and aTF are independent risk factors for ACI.

Action mechanism of an angiotensin I-converting enzyme inhibitory peptide derived from chicken breast muscle

In a previous study, we isolated the inhibitory peptide (P4 peptide, Gly-Phe-Hyp-Gly-Thr-Hyp-Gly-Leu-Hyp-Gly-Phe) for angiotensin I-converting enzyme (ACE) from chicken breast muscle extract possessing hypotensive activity for spontaneously hypertensive rats (SHRs). This study was performed to elucidate the peptide's action mechanisms of inhibiting ACE. Intravenous administration of synthetic P4 peptide resulted in significant drops in the blood pressures of SHRs. As Dixon plots indicate, the P4 peptide showed high affinity toward ACE (K(i) = 11.48 microM) and only 10% of the total amount of the P4 peptide was decomposed. The analyses of the relationship between the ACE inhibitory activity and structure of the P4 peptide clarified that Hyp-Gly-Leu-Hyp-Gly-Phe showed a stronger activity (IC50 = 10 microM) than the P4 peptide (IC50 = 46 microM). When Phe at the C-terminus of the P4 peptide was deleted, IC50 changed to 25000 microM, indicating that Phe at the C-terminus of the peptide is very important for ACE inhibitory activity.

Noncardiac consequences of hypertension in hemodialysis patients

The incidence of cerebrovascular events and peripheral vascular disease is higher in dialysis patients compared to the general population. Although normotensive dialysis patients have an elevated risk of stroke, hypertension remains an important risk factor for symptomatic cerebrovascular accidents. The risk of stroke increases in a linear fashion with blood pressure (BP) level. Furthermore, hypertension is also an important risk factor for silent cerebral infarction in dialysis patients. With regard to peripheral vascular disease, the association with hypertension is less clear. The spectrum of cerebrovascular accidents differs from the general population, as the relative incidence of cerebral hemorrhage to cerebral infarction is much higher. The prognosis of cerebral hemorrhage is poor and depends on the size and location of the hemorrhage. In order to prevent noncardiac complications, strict control of hypertension is of major importance in dialysis patients.