European Journal of Cardiovascular Medicine

Ischemic stroke is a leading cause of disability and mortality worldwide, primarily resulting from cerebral arterial occlusion due to atherosclerosis and thromboembolism (1). It accounts for approximately 87% of all stroke cases and is strongly associated with traditional cardiovascular risk factors, including dyslipidemia, hypertension, diabetes, and smoking (2,3). Among these, lipid abnormalities play a crucial role in the development of atherosclerotic plaques, leading to carotid artery stenosis and subsequent cerebrovascular events (4).

Dyslipidemia, particularly elevated levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG), along with reduced high-density lipoprotein cholesterol (HDL-C), contributes significantly to atherosclerosis by promoting endothelial dysfunction, inflammation, and plaque instability (5,6). Carotid atherosclerosis, evaluated through Doppler ultrasound, serves as a critical predictor of ischemic stroke, allowing for the assessment of plaque morphology, degree of stenosis, and vascular flow abnormalities (7). Studies have shown that increased intima-media thickness (IMT) and the presence of complex or ulcerated plaques are associated with a higher risk of stroke (8,9).

While previous studies have examined the role of lipid profiles in cardiovascular disease, the specific relationship between lipid abnormalities and carotid artery plaque characteristics in ischemic stroke patients remains an area of active research. Understanding this association is essential for improving risk stratification and optimizing preventive strategies. The present study aims to evaluate the correlation between lipid profile parameters and carotid artery plaque characteristics in ischemic stroke patients using Doppler ultrasound.

Study Design and Population

This hospital-based cross-sectional study was conducted on ischemic stroke patients admitted to the neurology department. A total of 100 patients, aged between 45 and 75 years, who were diagnosed with ischemic stroke based on clinical and radiological findings (CT/MRI) were included. Patients with hemorrhagic stroke, malignancy, autoimmune disorders, or prior carotid interventions were excluded.

Data Collection and Laboratory Investigations

Demographic details, medical history, and risk factors such as hypertension, diabetes, and smoking status were recorded. Blood samples were collected following an overnight fast for lipid profile analysis, including total cholesterol (TC), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), and triglycerides (TG). Lipid levels were measured using an automated enzymatic colorimetric assay.

Carotid Doppler Ultrasonography

Carotid artery assessment was performed using Doppler ultrasound with a high-resolution linear probe (7–12 MHz). The presence, location, and characteristics of plaques were evaluated, along with intima-media thickness (IMT) and degree of stenosis. Plaques were categorized as echogenic or echolucent, and stenosis was graded as mild (<50%), moderate (50–70%), or severe (>70%) based on established criteria.

Statistical Analysis

Descriptive statistics were used to summarize demographic and clinical data. The association between lipid parameters and carotid plaque severity was analyzed using Pearson’s correlation and chi-square tests. A p-value <0.05 was considered statistically significant. All analyses were performed using SPSS software version 25.0.

Demographic and Clinical Characteristics

A total of 100 ischemic stroke patients were included in the study, with a mean age of 62.4 ± 8.5 years. Among them, 58% were male and 42% were female. Hypertension was present in 72% of patients, diabetes in 48%, and smoking history in 35% (Table 1).

Lipid Profile and Carotid Artery Plaque Findings

Lipid profile analysis revealed that 70% of patients had elevated LDL-C levels (>130 mg/dL), while 55% had low HDL-C levels (<40 mg/dL). The mean total cholesterol (TC) level was 210 ± 25 mg/dL, mean LDL-C was 150 ± 20 mg/dL, mean HDL-C was 38 ± 5 mg/dL, and mean triglycerides (TG) were 180 ± 30 mg/dL. A significant association was observed between elevated LDL-C and the presence of carotid plaques (Table 2).

Carotid Doppler Findings

Carotid Doppler ultrasound detected plaques in 65% of patients. Among these, 40% had mild stenosis (<50%), 20% had moderate stenosis (50–70%), and 5% had severe stenosis (>70%). Echolucent plaques were observed in 55% of cases, while mixed echogenicity plaques were found in 45%. A strong positive correlation (r = 0.72, p < 0.01) was noted between LDL-C levels and plaque severity (Table 3).

Tables

Table 1: Baseline Characteristics of the Study Population

Table 2: Lipid Profile of Ischemic Stroke Patients

Table 3: Carotid Doppler Ultrasound Findings

The results indicate that ischemic stroke patients with high LDL-C levels are more likely to develop carotid plaques, with a higher prevalence of echolucent plaques and varying degrees of stenosis (Table 3).

This study highlights a significant correlation between lipid profile abnormalities and carotid artery plaque formation in ischemic stroke patients. Dyslipidemia, particularly elevated LDL-C and reduced HDL-C levels, plays a crucial role in the pathogenesis of atherosclerosis, which is a key contributor to stroke incidence (1). Carotid atherosclerosis, as assessed by Doppler ultrasound, is an essential predictor of stroke risk, helping identify patients who may benefit from early intervention (2,3).

Our findings indicate that 70% of ischemic stroke patients had elevated LDL-C levels, and 65% exhibited carotid plaques. This aligns with previous studies that have reported a higher prevalence of carotid artery disease in patients with dyslipidemia (4,5). Elevated LDL-C is known to promote endothelial dysfunction, oxidative stress, and inflammatory responses, leading to plaque formation and progression (6). Conversely, low HDL-C levels contribute to impaired reverse cholesterol transport, further exacerbating atherosclerotic changes (7,8).

The study also observed that 40% of patients had mild stenosis, while 25% had moderate to severe stenosis, emphasizing the role of lipid abnormalities in determining plaque burden and severity. Similar findings have been reported, suggesting that increased LDL-C levels correlate with greater plaque thickness and vulnerability (9). Additionally, the predominance of echolucent plaques in 55% of cases suggests a higher risk of plaque rupture and embolization, which is associated with ischemic events (10,11).

Carotid Doppler ultrasound has proven to be a valuable non-invasive tool for detecting atherosclerotic changes in stroke patients (12). The present study reinforces the importance of incorporating routine carotid imaging in patients with dyslipidemia to identify those at high risk of cerebrovascular events. Previous research has demonstrated that lipid-lowering therapies, particularly statins, significantly reduce plaque progression and improve cardiovascular outcomes in patients with carotid atherosclerosis (13,14).

These findings suggest that early screening and aggressive management of dyslipidemia could help prevent stroke recurrence and reduce the overall disease burden. Lifestyle modifications, including dietary changes, physical activity, and smoking cessation, along with pharmacological interventions such as statins, have shown to be effective in stabilizing plaques and lowering stroke risk (15).

Despite the study’s strengths, including a well-defined cohort and standardized Doppler ultrasound assessment, certain limitations should be acknowledged. The cross-sectional nature of the study does not establish a causal relationship between lipid profile alterations and plaque formation. Additionally, factors such as inflammatory markers and genetic predisposition, which may contribute to carotid atherosclerosis, were not assessed. Future longitudinal studies are required to further explore these associations and determine the long-term impact of lipid management on stroke prevention.

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