Association between oxidized low-density lipoprotein and cognitive impairment in patients with ischemic stroke

Prevalence and Risk Factors of Poststroke Cognitive Impairment: A Systematic Review and Meta-Analysis

BACKGROUND

Stroke is a common disease that poses a significant threat to human health. Approximately one-third of stroke patients experience poststroke cognitive impairment (PSCI), which severely impacts their quality of life and survival time. Although the prevalence and risk factors for PSCI have been widely reported, these results have not been synthesized.

OBJECTIVES

This systematic review was conducted to explore the prevalence and risk factors of PSCI.

METHODS

PubMed, EMBASE, Web of Science, and Cochrane Library were comprehensively searched for studies exploring the prevalence and risk factors of PSCI from inception to July 5, 2022.

RESULTS

A total of 49 articles were included for meta-analysis. It was found that the combined prevalence of PSCI was 39%-47%. Risk factors for PSCI include female gender, age, education level less than 7 years, atrial fibrillation, diabetes, smoking, drinking, hypertension, coronary artery disease, carotid artery plaque, admission NIHSS score ≥ 5, unemployment, and homocysteine.

CONCLUSIONS

This systematic review has revealed a combined prevalence of PSCI is ranging from 39% to 47% and identified several risk factors for PSCI. These findings indicate a high incidence of the condition and underscore the need for increased public awareness. Future investigations should prioritize the identification of PSCI risk factors, providing a theoretical basis for nursing professionals to effectively manage and treat PSCI patients.

Atherogenic circulating lipoproteins in ischemic stroke

The fundamental role of qualitative alterations of lipoproteins in the early development of atherosclerosis has been widely demonstrated. Modified low-density lipoproteins (LDL), such as oxidized LDL (oxLDL), small dense LDL (sdLDL), and electronegative LDL [LDL(-)], are capable of triggering the atherogenic process, favoring the subendothelial accumulation of cholesterol and promoting inflammatory, proliferative, and apoptotic processes characteristic of atherosclerotic lesions. In contrast, high-density lipoprotein (HDL) prevents and/or reverses these atherogenic effects. However, LDL's atherogenic and HDL's anti-atherogenic actions may result altered in certain pathological conditions. The molecular mechanisms underlying the impaired effects of altered lipoproteins have been studied in numerous in vitro and in vivo studies, and have been extensively analyzed in coronary atherosclerosis, especially in the context of pathologies such as dyslipidemia, diabetes, obesity, and metabolic syndrome. However, the corresponding studies are scarcer in the field of ischemic stroke, despite carotid arteriosclerosis progression underlies at least 20% of ischemic strokes. The present review relates qualitative alterations of LDL and HDL with the development of carotid arteriosclerosis and the occurrence of ischemic stroke.

The Role of Potential Oxidative Biomarkers in the Prognosis of Acute Ischemic Stroke and the Exploration of Antioxidants as Possible Preventive and Treatment Options

Ischemic strokes occur when the blood supply to a part of the brain is interrupted or reduced due to arterial blockage, and it often leads to damage to brain cells or death. According to a myriad of experimental studies, oxidative stress is an important pathophysiological mechanism of ischemic stroke. In this narrative review, we aimed to identify how the alterations of oxidative stress biomarkers could suggest a severity-reflecting diagnosis of ischemic stroke and how these interactions may provide new molecular targets for neuroprotective therapies. We performed an eligibility criteria-based search on three main scientific databases. We found that patients with acute ischemic stroke are characterized by increased oxidative stress markers levels, such as the total antioxidant capacity, F2-isoprostanes, hydroxynonenal, total and perchloric acid oxygen radical absorbance capacity (ORACTOT and ORACPCA), malondialdehyde (MDA), myeloperoxidase, and urinary 8-oxo-7,8-dihydro-2′-deoxyguanosine. Thus, acute ischemic stroke is causing significant oxidative stress and associated molecular and cellular damage. The assessment of these molecular markers could be useful in diagnosing ischemic stroke, finding its causes, predicting its severity and outcomes, reducing its impact on the cellular structures of the brain, and guiding preventive treatment towards antioxidant-based therapy as novel therapeutic alternatives.

Risk Factors Affecting Cognitive Impairment of the Elderly Aged 65 and Over: A Cross-Sectional Study

Objectives

Elderly population with cognitive impairment has been accelerating in China. This study aimed to explore the relationship between each risk factor and each cognitive domain to provide evidence for risk prevention of controlling impaired cognitive function in elderly.

Methods

This cross-sectional study analyzed the cognitive status of the elderly aged 65 and above in three communities in Shizhong District of Jinan City. Cognitive status was assessed by MMSE. The influencing factors of cognitive impairment were analyzed by chi square test, correlation analysis and regression analysis.

Results

Among 1,171 participants, 643 were defined as cognitive impairment with an incidence of 54.9%. And we found that there were significant differences in the incidence of cognitive impairment among residents with different gender, age, education level, hypertension and LDL-C (P < 0.05). However, BMI, marital status, smoking, physical exercise, T2DM, TC, TG and HDL-C had no significant differences in the incidence of cognitive impairment. In addition, education level (b = 1.194, P <0.001), age (b = −0.040, P = 0.001), LDL-C (b = 0.169, P = 0.018) had statistical significance on the total score of MMSE according to binary logistic regression analysis.

Conclusion

Gender, age, education level, hypertension and LDL-C had significant differences in the incidence of cognitive impairment. And these risk factors could provide a basis for the early screening and intervention of cognitive impairment in the elderly.

Soluble ST2 and risk of cognitive impairment after acute ischemic stroke: a prospective observational study

BACKGROUND

Soluble suppression of tumorigenesis-2 (sST2) was reported to be associated with cognitive performance and risk of incident stroke. However, the impact of sST2 on cognitive function after ischemic stroke is unclear. We aimed to assess the association of sST2 and cognitive impairment at 3 months in acute ischemic stroke patients.

METHODS

Baseline plasma sST2 levels were measured in 619 ischemic stroke patients (mean age: 60.0 ± 10.5 years) from 7 participating hospitals of the China Antihypertensive Trial in Acute Ischemic Stroke. Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) were used to assess cognitive status. Cognitive impairment was defined as a MoCA score < 23 or MMSE score < 27. The association between sST2 and cognitive impairment was evaluated by logistic regression analysis.

RESULTS

325 (52.5%) or 323 (52.2%) participants developed cognitive impairment according to MoCA or MMSE. After adjustment for age, sex, education, and other covariates, the odds ratio for the highest vs lowest quartile of sST2 was 2.38 (95% CI, 1.42-4.00) and 1.82 (95% CI 1.09-3.03) risk of cognitive impairment defined by MoCA and MMSE score, respectively. Incorporation sST2 into a model containing conventional risk factors significantly improved reclassification.

CONCLUSIONS

Elevated plasma sST2 levels were significantly associated with post-stroke cognitive impairment.

Diagnostic and prognostic blood biomarkers in vascular dementia: From the viewpoint of ischemic stroke

Reliable quantitative blood biomarkers are important in vascular dementia (VaD) because early diagnosis and therapeutic intervention are effective in preventing progression of dementia. Although many blood biomarkers for acute ischemic stroke (AIS) or VaD have been reported, there are few reliable blood biomarkers. VaD and AIS have similar pathological conditions that are associated with small vessel disease (SVD) such as oxidative stress, inflammation, endothelial dysfunction, and neuronal injury. Therefore, it may be possible to find superior blood biomarkers of VaD among AIS blood biomarkers. Owing to recent developments, noncoding RNAs such as microRNA and long noncoding RNA, which can be analyzed using a single drop of blood, are also particularly reliable VaD markers because they stably reflect brain tissue damage. A multimarker combining several blood biomarkers or artificial intelligence technology may also be beneficial to compensate for insufficiencies of a single blood biomarker. This review describes the blood biomarkers of VaD and how they are related to blood biomarkers of AIS.

The Role of Oxidative Stress in Cardiovascular Aging and Cardiovascular Diseases

Aging can be seen as process characterized by accumulation of oxidative stress induced damage. Oxidative stress derives from different endogenous and exogenous processes, all of which ultimately lead to progressive loss in tissue and organ structure and functions. The oxidative stress theory of aging expresses itself in age-related diseases. Aging is in fact a primary risk factor for many diseases and in particular for cardiovascular diseases and its derived morbidity and mortality. Here we highlight the role of oxidative stress in age-related cardiovascular aging and diseases. We take into consideration the molecular mechanisms, the structural and functional alterations, and the diseases accompanied to the cardiovascular aging process.

Oxidative Stress at the Crossroads of Aging, Stroke and Depression

Epidemiologic studies have shown that in the aging society, a person dies from stroke every 3 minutes and 42 seconds, and vast numbers of people experience depression around the globe. The high prevalence and disability rates of stroke and depression introduce enormous challenges to public health. Accumulating evidence reveals that stroke is tightly associated with depression, and both diseases are linked to oxidative stress (OS). This review summarizes the mechanisms of OS and OS-mediated pathological processes, such as inflammation, apoptosis, and the microbial-gut-brain axis in stroke and depression. Pathological changes can lead to neuronal cell death, neurological deficits, and brain injury through DNA damage and the oxidation of lipids and proteins, which exacerbate the development of these two disorders. Additionally, aging accelerates the progression of stroke and depression by overactive OS and reduced antioxidant defenses. This review also discusses the efficacy and safety of several antioxidants and antidepressants in stroke and depression. Herein, we propose a crosstalk between OS, aging, stroke, and depression, and provide potential therapeutic strategies for the treatment of stroke and depression.

The emerging role of cell senescence in atherosclerosis

Cell senescence is a fundamental mechanism of aging and appears to play vital roles in the onset and prognosis of cardiovascular disease, fibrotic pulmonary disease, liver disease and tumor. Moreover, an increasing body of evidence shows that cell senescence plays an indispensable role in the formation and development of atherosclerosis. Multiple senescent cell types are associated with atherosclerosis, senescent human vascular endothelial cells participated in atherosclerosis via regulating the level of endothelin-1 (ET-1), nitric oxide (NO), angiotensin II and monocyte chemoattractant protein-1 (MCP-1), senescent human vascular smooth muscle cells-mediated plaque instability and vascular calcification via regulating the expression level of BMP-2, OPN, Runx-2 and inflammatory molecules, and senescent macrophages impaired cholesterol efflux and promoted the development of senescent-related cardiovascular diseases. This review summarizes the characteristics of cell senescence and updates the molecular mechanisms underlying cell senescence. Moreover, we also discuss the recent advances on the molecular mechanisms that can potentially regulate the development and progression of atherosclerosis.

The neuroprotective mechanisms of ginkgolides and bilobalide in cerebral ischemic injury: a literature review

The incidence and mortality of strokes have increased over the past three decades in China. Ischemic strokes can cause a sequence of detrimental events in patients, including increased permeability and dysfunction of the blood-brain barrier, brain edema, metabolic disturbance, endoplasmic reticulum stress, autophagy, oxidative stress, inflammation, neuron death and apoptosis, and cognitive impairment. Thrombolysis using recombinant tissue plasminogen activator (rtPA) and mechanical embolectomy with a retrievable stent are two recognized strategies to achieve reperfusion after a stroke. Nevertheless, rtPA has a narrow therapeutic timeframe, and mechanical embolectomy has limited rates of good neurological outcomes. EGb761 is a standardized and extensively studied extract of Ginkgo biloba leaves. The ginkgolides and bilobalide that constitute a critical part of EGb761 have demonstrated protective properties towards cerebral injury. Ginkgolides include Ginkgolide A (GA), Ginkgolide B (GB), Ginkgolide C (GC), Ginkgolide J (GJ), Ginkgolide K (GK), Ginkgolide L (GL), and Ginkgolide M (GM). This review seeks to elucidate the neuroprotective effects and mechanisms of ginkgolides, especially GA and GB, and bilobalide in cerebral injury following ischemic strokes.

The Role of Oxidative Stress in Common Risk Factors and Mechanisms of Cardio-Cerebrovascular Ischemia and Depression

The public health sector faces a huge challenge as a result of the high prevalence and burden of disability caused by ischemic cardio-cerebrovascular disease (CVD) and depression. Although studies have explored the underlying mechanisms and potential therapies to address conditions, there is no treatment breakthrough, especially for depression which is highly influenced by social stressors. However, accumulating evidence reveals that CVD and depression are correlated and share common risk factors, particularly obesity, diabetes, and hypertension. They also share common mechanisms, including oxidative stress (OS), inflammation and immune response, cell death signaling pathway, and microbiome-gut-brain axis. This review summarizes the relationship between ischemic CVD and depression and describes the interactions among common risk factors and mechanisms for these two diseases. In addition, we propose that OS mediates the crosstalk between these diseases. We also reveal the potential of antioxidants to ameliorate OS-related injuries.

What is the Current Role for Vitamin D and the Risk of Stroke?

INTRODUCTION

Increasing evidence supports the relationship between vitamin D and stroke. Vitamin D has now been proposed as a prognostic biomarker also for functional outcome in stroke patients.

METHODS

A revision of the data suggests that low vitamin D is associated more with ischemic than with haemorrhagic stroke, even if the role of optimal vitamin D levels for vascular wall is still unclear. Vitamin D deficiency induces with different mechanisms an alteration of vascular wall.

RESULTS

However, to date, the research supporting the effectiveness of vitamin D supplementation in stroke and in post-stroke recovery is still inadequate and conclusive evidences have not been published.

CONCLUSION

In this review, we provide a better understanding of the role of vitamin D in stroke.

Association between vitamin D status and cognitive impairment in acute ischemic stroke patients: a prospective cohort study

Objective

Previous studies found that low vitamin D levels were modestly associated with risk of stroke and poor functional outcome after stroke. In addition, vitamin D deficiency has been linked with cognitive decline. Our study aimed to explore the potential relationship between vitamin D levels in the short-term acute phase of ischemic stroke and cognitive impairment at 1 month.

Methods

In total, 354 ischemic stroke patients were consecutively enrolled in the study and received 1-month follow-up. The serum levels of vitamin D were measured within 24 hours after admission. Cognitive function was evaluated by the Mini-Mental State Examination (MMSE) at 1 month after acute ischemic stroke. Cognitive impairment was defined according to different education levels.

Results

According to MMSE scores, 114 participants (32.2%) had cognitive impairment at 1 month. Patients with vitamin D deficiency were more likely to have cognitive impairment than those with vitamin D insufficiency and vitamin D sufficiency (P<0.001). After adjusting for potential confounders in our Cox proportional hazards model, vitamin D deficiency was independently associated with the development of cognitive impairment in acute ischemic stroke patients.

Conclusion

Independent of established risk factors, vitamin D deficiency in the short-term phase of ischemic stroke was associated with a higher incidence of 1-month cognitive impairment.

The relationship between oxidized low-density lipoprotein and related ratio and acute cerebral infarction

This study aimed to study the value of oxidized low-density lipoprotein (OX-LDL) and related ratio in the diagnosis of acute cerebral infarction and the classification of acute cerebral infarction.Of the 129 patients enrolled in this study, 94 patients with acute cerebral infarction were assigned to the case group, and 35 healthy subjects were enrolled as control group (n = 35). And then the case group were divided into large-artery atherosclerosis (LAA) group (n = 61) and small-artery occlusion (SAO) group (n = 33) according to the TOAST classification standard. Plasma OX-LDL levels were determined by enzyme-linked immunosorbent assay. OX-LDL/total cholesterol (OX-LDL/TC), OX-LDL/high-density lipoprotein (OX-LDL/HDL), OX-LDL/LDL were calculated.There were significant differences in OX-LDL, OX-LDL/TC, OX-LDL/HDL, and OX-LDL/LDL in patients with acute cerebral infarction and those in control group (P < .001). The area under the receiver-operating characteristic curve of OX-LDL and related ratio was >0.7 (P < .001). There was a slight positive correlation between OX-LDL/TC and National Institutes of Health Stroke Scale score at admission (r = 0.265, P = .039) in the LAA group.OX-LDL, OX-LDL/TC, OX-LDL/HDL, and OX-LDL/LDL were closely related to acute cerebral infarction, especially with large atherosclerotic cerebral infarction. OX-LDL/TC can reflect the severity of acute cerebral infarction for LAA, but it cannot predict the short-term prognosis of acute cerebral infarction.

Using the Oxford Cognitive Screen to Detect Cognitive Impairment in Stroke Patients: A Comparison with the Mini-Mental State Examination

Background

The Oxford Cognitive Screen (OCS) was recently developed with the aim of describing the cognitive deficits after stroke. The scale consists of 10 tasks encompassing five cognitive domains: attention and executive function, language, memory, number processing, and praxis. OCS was devised to be inclusive and un-confounded by aphasia and neglect. As such, it may have a greater potential to be informative on stroke cognitive deficits of widely used instruments, such as the Mini-Mental State Examination (MMSE) or the Montreal Cognitive Assessment, which were originally devised for demented patients.

Objective

The present study compared the OCS with the MMSE with regards to their ability to detect cognitive impairments post-stroke. We further aimed to examine performance on the OCS as a function of subtypes of cerebral infarction and clinical severity.

Methods

325 first stroke patients were consecutively enrolled in the study over a 9-month period. The OCS and MMSE, as well as the Bamford classification and NIHSS, were given according to standard procedures.

Results

About a third of patients (35.3%) had a performance lower than the cutoff (<22) on the MMSE, whereas 91.6% were impaired in at least one OCS domain, indicating higher incidences of impairment for the OCS. More than 80% of patients showed an impairment in two or more cognitive domains of the OCS. Using the MMSE as a standard of clinical practice, the comparative sensitivity of OCS was 100%. Out of the 208 patients with normal MMSE performance 180 showed impaired performance in at least one domain of the OCS. The discrepancy between OCS and MMSE was particularly strong for patients with milder strokes. As for subtypes of cerebral infarction, fewer patients demonstrated widespread impairments in the OCS in the Posterior Circulation Infarcts category than in the other categories.

Conclusion

Overall, the results showed a much higher incidence of cognitive impairment with the OCS than with the MMSE and demonstrated no false negatives for OCS vs MMSE. It is concluded that OCS is a sensitive screen tool for cognitive deficits after stroke. In particular, the OCS detects high incidences of stroke-specific cognitive impairments, not detected by the MMSE, demonstrating the importance of cognitive profiling.

Low levels of serum magnesium are associated with poststroke cognitive impairment in ischemic stroke patients

PURPOSE

Population-based studies have revealed a high prevalence of cognitive impairment after stroke. We aimed to determine the impact of serum magnesium (Mg²⁺) levels on the occurrence of poststroke cognitive impairment (PSCI).

PATIENTS AND METHODS

Acute ischemic stroke patients (n = 327) were enrolled in our study and serum Mg²⁺ levels were assessed on admission. The cognitive performance of each patient was evaluated using the Mini-Mental State Examination (MMSE) at a 1-month follow-up visit.

RESULTS

One hundred five (32.1%) patients were diagnosed with PSCI at 1-month poststroke. The serum Mg²⁺ levels in both the PSCI group and the non-PSCI group were significantly lower than those in normal control group (P<0.001). In addition, the PSCI group had lower levels of serum Mg²⁺ compared to the non-PSCI group (P=0.003). In the binary logistic regression analysis, a serum Mg²⁺ level of ≤0.82 mmol/L was significantly associated with an increased risk of developing PSCI by the 1-month follow-up (OR 2.236, 95% CI 1.232-4.058, P=0.008), as was age (OR 1.043, 95% CI 1.014-1.073, P=0.003).

CONCLUSION

Our results demonstrate the existence of a significant association between low levels of serum Mg²⁺ and the occurrence of PSCI 1-month poststroke, and these results suggest that low levels of serum Mg²⁺ on admission may serve as a risk factor for developing PSCI by 1-month poststroke.