Kwang Yeol Park

Ischemic Stroke and Cancer: Stroke Severely Impacts Cancer Patients, While Cancer Increases the Number of Strokes

Background Cancer and ischemic stroke are two of the most common causes of death among the elderly, and associations between them have been reported. However, the main pathomechanisms of stroke in cancer patients are not well known, and can only be established based on accurate knowledge of the characteristics of cancer-related strokes. We review herein recent studies concerning the clinical, laboratory, and radiological features of patients with cancer-related stroke. Main Contents This review covers the epidemiology, underlying mechanisms, and acute and preventive treatments for cancer-related stroke. First, the characteristics of stroke (clinical and radiological features) and systemic cancer (type and extent) in patients with cancer-specific stroke are discussed. Second, the role of laboratory tests in the early identification of patients with cancer-specific stroke is discussed. Specifically, serum D-dimer levels (as a marker of a hypercoagulable state) and embolic signals on transcranial Doppler (suggestive of embolic origin) may provide clues regarding changes in the levels of coagulopathy related to cancer and anticoagulation. Finally, strategies for stroke treatment in cancer patients are discussed, emphasizing the importance of preventive strategies (i.e., the use of anticoagulants) over acute revascularization therapy in cancer-related stroke. Conclusion Recent studies have revealed that the characteristics of cancer-related stroke are distinct from those of conventional stroke. Our understanding of the characteristics of cancer-related stroke is essential to the correct management of these patients. The studies presented in this review highlight the importance of a personalized approach in treating stroke patients with cancer.

Symptomatic Hemorrhagic Transformation and Its Predictors in Acute Ischemic Stroke with Atrial Fibrillation

Background and Purpose: Patients with acute cardioembolic stroke frequently show hemorrhagic transformation (HTr). We attempted to identify predictors of symptomatic HTr in acute ischemic stroke with atrial fibrillation (AF). Methods: Of the consecutive acute ischemic stroke patients with AF at 12 hospitals in Korea, patients with posterior circulation stroke or thrombolytic therapy were excluded. Immediate anticoagulation was recommended to all patients, except those with: (1) large infarcts, 50% or more of the middle cerebral artery territory, (2) significant HTr on initial imaging, or (3) other safety concerns. Symptomatic HTr was defined as cerebral hemorrhage temporally related to neurological deterioration. Results: Of the 389 included patients (mean age 71 years), 260 (67%) were treated with anticoagulation within 1 week from the onset. Symptomatic HTr occurred in 4.6%. Large infarct (OR 6.38, 95% CI 1.16–35.14), previous hemorrhagic stroke (OR 10.67, 1.77–64.25), and low platelet count (OR per 104 increase 0.87, 0.79–0.97) were independent predictors of symptomatic HTr. hsCRP values tended to be higher in patients with symptomatic HTr (p = 0.055). Conclusions: Caution is needed in anticoagulation treatment of acute cardioembolic stroke patients with a large infarct, previous hemorrhagic stroke, low platelet count, or a high hsCRP level.

Large-Artery Stenosis Predicts Subsequent Vascular Events in Patients with Transient Ischemic Attack

Background and purpose We investigated subsequent vascular events in patients with transient ischemic attack (TIA) and determined the predictors of such events among vascular risk factors including large-artery disease, TIA-symptom duration, and acute ischemic lesions on diffusion-weighted imaging (DWI). Methods We identified 98 consecutive patients with TIA who visited a tertiary university hospital and underwent DWI and brain magnetic resonance angiography within 48 hours of symptom onset. We reviewed the medical records to assess the clinical characteristics of TIA, demographics, and the subsequent vascular events including acute ischemic stroke, TIA, and myocardial infarction. Results Large-artery disease was detected in 55 patients (56%). Ten patients (10%) experienced TIA symptoms for longer than 1 hour, and acute infarctions on DWI were identified in 30 patients (31%). During the mean follow-up period of 19 months, seven patients (7%) had an acute ischemic stroke and 20 patients (20%) had TIA. Retinal artery occlusion in two patients, spinal cord infarction in one patient, and peripheral vascular claudication in one patient were also recorded. Cox proportional-hazards multivariate analysis revealed that large-artery disease was an independent predictor of subsequent cerebral ischemia (hazard ratio [HR], 2.8; 95% confidence interval [CI], 1.1-7.1; p=0.02) and subsequent vascular events (HR, 2.9; 95% CI, 1.2-6.7; p=0.01). Conclusions In patients with TIA, large-artery disease is an independent predictor of subsequent vascular events. Acute infarction on DWI and a symptom duration of more than 1 hour are not significantly correlated with a higher risk of subsequent vascular events. These findings suggest that the underlying vascular status is more important than symptom duration or acute ischemic lesion on DWI.

Comprehensive Application of the International Classification of Headache Disorders Third Edition, Beta Version

The purpose of this study was to test the feasibility and usefulness of the International Classification of Headache Disorders, third edition, beta version (ICHD-3β), and compare the differences with the International Classification of Headache Disorders, second edition (ICHD-2). Consecutive first-visit patients were recruited from 11 headache clinics in Korea. Headache classification was performed in accordance with ICHD-3β. The characteristics of headaches were analyzed and the feasibility and usefulness of this version was assessed by the proportion of unclassified headache disorders compared with ICHD-2. A total of 1,627 patients were enrolled (mean age, 47.4±14.7 yr; 62.8% female). Classification by ICHD-3β was achieved in 97.8% of headache patients, whereas 90.0% could be classified by ICHD-2. Primary headaches (n=1,429, 87.8%) were classified as follows: 697 migraines, 445 tension-type headaches, 22 cluster headaches, and 265 other primary headache disorders. Secondary headache or painful cranial neuropathies/other facial pains were diagnosed in 163 patients (10.0%). Only 2.2% were not classified by ICHD-3β. The main reasons for missing classifications were insufficient information (1.6%) or absence of suitable classification (0.6%). The diagnoses differed from those using ICHD-2 in 243 patients (14.9%). Among them, 165 patients were newly classified from unclassified with ICHD-2 because of the relaxation of the previous strict criteria or the introduction of a new diagnostic category. ICHD-3β would yield a higher classification rate than its previous version, ICHD-2. ICHD-3β is applicable in clinical practice for first-visit headache patients of a referral hospital.

Differences of Ankle-Brachial Index according to Ischemic Stroke Subtypes: The Peripheral Artery Disease in Korean Patients with Ischemic Stroke (PIPE) Study

Background/Aims: Although previous studies showed a high prevalence of abnormal ankle-brachial index (ABI) in patients with ischemic stroke, few data exist regarding ABI in Asian patients with ischemic stroke. The purpose of the present study was to determine the prevalence and factors associated with abnormal ABI (≤0.9) in a cohort of ischemic stroke patients. Methods: In this prospective multicenter study, 1,293 patients diagnosed with acute ischemic stroke or transient ischemic attack underwent ABI measurement to evaluate an association between abnormal ABI and vascular risk factors and clinical characteristics. Differences in ABI by stroke subtypes were also assessed. Results: Abnormal ABI of ≤0.9 was found in 13.0%. Patients with abnormal ABI were more likely to be older and had higher initial stroke severity. The prevalence of abnormal ABI was 18.4% in large artery atherosclerosis, 7% in small artery disease, and 19.2% in cardioembolism (p < 0.001). Multiple logistic regression analysis showed that age, hyperlipidemia, diabetes, and large artery atherosclerosis subtype were independent factors associated with abnormal ABI. Conclusions: These data suggest that the prevalence of abnormal ABI in Korean patients with ischemic stroke was lower than that in Caucasian patients, which might be associated with ethnic differences in underlying stroke subtypes.

Chronic Daily Headache and Medication Overuse Headache in First-Visit Headache Patients in Korea: A Multicenter Clinic-Based Study.

Background and Purpose Chronic daily headache (CDH) is defined as a headache disorder in which headaches occur on a daily or near-daily basis (at least 15 days/month) for more than 3 months. Chronic migraine (CM) and medication overuse headache (MOH) are very disabling headaches that remain underdiagnosed. The aim of this study was to establish the frequency of CDH and its various subtypes, and examine the associations with MOH among first-visit headache patients presenting at neurology outpatient clinics in Korea. Methods Eleven neurologists enrolled first-visit patients with complaints of headaches into outpatient clinics for further assessment. Headache disorders were classified according to the International Classification of Headache Disorder (third edition beta version) by each investigator. Results Primary CDH was present in 248 (15.2%) of the 1,627 included patients, comprising CM (143, 8.8%), chronic tension-type headache (CTTH) (98, 6%), and definite new daily persistent headache (NDPH) (7, 0.4%). MOH was associated with headache in 81 patients (5%). The association with MOH was stronger among CM patients (34.5%) than patients with CTTH (13.3%) or NDPH (14.3%) (p=0.001). The frequency of CDH did not differ between secondary and tertiary referral hospitals. Conclusions The frequencies of CDH and MOH diagnoses were 15.2% and 5%, respectively in first-visit headache patients presented at secondary or tertiary referral hospitals in Korea. CM was the most common subtype of CDH and was most frequently associated with MOH.

Incidence and Etiology of Microinfarcts in Patients with Ischemic Stroke: Etiology of Microinfarcts

Cerebral microinfarcts (CMI) are associated with intracerebral hemorrhage due to small vessel disease (SVD) in studies not including an ischemic etiologic workup. We aimed to determine their incidence and potential causes in a large ischemic stroke (IS) cohort.