ETIOLOGICAL STRUCTURE AND COMORBIDITY IN ACUTE ISCHEMIC STROKE

Abstract

Abstract:
The objective of this study was to investigate the etiological factors, comorbid conditions, risk factors, and gender-specific diagnostic significance in the development of different subtypes of acute ischemic stroke (AIS).

Materials and Methods:
This observational study included 42 patients with acute ischemic strokes affecting various cerebral arterial territories. The average age was 66.5 years (ranging from 49 to 85 years), with men averaging 63 years and women 70 years. Detailed complaints, disease progression, lifestyle histories, physical examination results, and instrumental indicators were thoroughly examined. Neurological deficits were assessed using the NIHSS scale. Cardiac activity was evaluated using EKG, duplex scanning, and echocardiography with the MINDRAY CONSONA N9 apparatus. MRI brain images were obtained using the Signa Explorer 1.5 TV T1, T2, and Dwi modes. Statistical analyses, including the T-test, chi-square, and ANOVA, were performed using Excel, with a significance level set at P = 0.05.

Results:
According to the WHO classification, the age distribution of patients showed that 54% were elderly (60–74 years), 24% were old (75–90 years), and 22% were middle-aged (45–59 years). The study group comprised 52% men and 48% women, with an average BMI of 29.3 kg/m² for men and 31.7 kg/m² for women. Among the patients, 8 had a gradual onset with dizziness and dysarthria, while 34 experienced a sudden onset with speech disturbances and hemiparesis, and some also lost consciousness. Men exhibited smoking and obesity, while atrial fibrillation was more common in women. No significant statistical difference was found between risk factors (diabetes mellitus, hypertension, obesity, smoking, atrial fibrillation, alcohol) and ischemic stroke subtypes (atherothrombotic, cardioembolic, lacunar, cryptogenic) (p = 0.826; p > 0.05). The NIHSS score averaged 7.5 (2–16) for women and 8 (0–16) for men. No gender differences in the development of AIS subtypes according to the NIHSS scale were identified. ( p = 0.249; p > 0.05). Statical analysis indicated significant differences in the severity of neurological deficits and subtypes (p = 0.002; p<0.05). Ischemic foci were located in the middle cerebri artery(MCA) region in 45% of cases; in 26%, no acute foci were identified on MRI, possibly due to the minimal formation of ischemic foci in the acute phase of AIS. Significant differences were found between the localization of ischemic foci in the cerebral hemispheres and different subtypes (p = 0.01; p<0.05).

Cardioembolic strokes often affect the MCA region bilaterally and the parietal region. Atherothrombotic strokes predominantly occurred in the left MCA, right periventricular  and parietal regions. Cryptogenic strokes were localized in the right posterior cerebral artery (PCA) region. Lacunar type ischemic foci were localized in the left periventricular region. Circulatory encephalopathy (CE) often showed atrophy in the frontal, parietal  and temporal regions.

Duplex scanning assessed blood flow volume and velocity in the common carotid arteries, internal carotid artery, external carotid artery  and vertebrobasilar artery. Hemodynamically significant stenosis (70%) was recorded in 4 patients, while 4 had non-hemodynamically significant stenosis (50–70%), and 7 had stenosis less than 50%. Stenoses were primarily localized symmetrically in the bifurcation area of the common carotid arteries and the internal carotid artery. AF patients' acute cerebrovascular accident  risk was evaluated using the CH2ADS2-VASc scale, averaging 2.75 for women (min - 1, max - 4) and 2.65 for men (min - 1, max - 5). No significant gender differences were identified in the risk of recurrent acute cerebrovascular accidents. AF was detected in 72% of cardioembolic stroke cases.

Based on the above data, the subtypes of ischemic stroke in 42 patients were identified: atherothrombotic in 13 cases, cardioembolic(CE) in 11 cases, lacunar in 1 case, TIA in 4 cases, DCE in 2 cases  and cryptogenic in 11 cases. The distribution of different AIS subtypes varied significantly (p = 0.005; p > 0.05).

Conclusion:
No statistically significant gender difference was found between risk factors and ischemic stroke. Risk factors such as smoking, alcoholism, and obesity were more common in men, while AF was more common among women. AI in men had an earlier onset (average 63 years) compared to women. The majority of the patients (54%) were elderly (60–74), highlighting the vulnerability of this age group and the need for a detailed examination of AIS risk factors. Cardioembolic and atherothrombotic strokes were more severe compared to TIA, cryptogenic and lacunar AIS subtypes (NIHSS data). In 26% of cases, CE was a significant factor, with atrial fibrillation being the primary cause in 72% of these cases (p = 0.001; p > 0.05). Other factors included artificial valves, mitral and aortic valve insufficiency and a low left ventricular ejection fraction. The high proportion of the cryptogenic subtype (26%) indicates the need for detailed examination of this category at specialized centers to identify the source of embolism and transition to appropriate AIS subtypes.