Teng-Yeow Tan

Prediction of Length of Stay of First-Ever Ischemic Stroke

Background and Purpose— Accurate information about hospital resource utilization is necessary for management of healthcare service. The purpose of this study was to determine the demographic and clinical predictors of length of hospital stay (LOS) of acute care hospitalization for first-ever ischemic stroke patients. Methods— A group of 330 patients who suffered from first-ever ischemic stroke and were consecutively admitted to a medical center in southern Taiwan were followed prospectively. Because our intention was to identify the major predictors of LOS from the information available at admission, we evaluated only those factors that could be assessed at the time of admission. Univariate analysis and multiple regression analysis were used to identify the main predictors of LOS. Results— The median LOS was 7 days (mean, 11 days; range, 1 to 122 days). Among the prespecified demographic and clinical characteristics, National Institutes of Health Stroke Scale (NIHSS) score at admission, the quadratic term of the initial NIHSS score, modified Barthel Index score at admission, small-vessel occlusion stroke, sex, and smoking were the main explanatory factors for LOS. In particular, for each 1-point increase in the total score of NIHSS, LOS increased approximately 1 day for patients with mild or moderate (score 0 to 15 points) neurological impairments, while LOS decreased approximately 1 day for patients with severe (score >15 points) neurological impairments. Conclusions— The severity of stroke, as rated by the total score on NIHSS, is an important factor that influences LOS after acute stroke hospitalization.

Prehospital Delay After Acute Stroke in Kaohsiung, Taiwan

Background and Purpose— Successful acute stroke intervention depends on early hospital presentation. Our study aimed to examine the extent of and factors associated with prehospital delays after acute stroke in Taiwan, where people are new to thrombolytic therapy for stroke. Methods— Data were prospectively collected from 196 patients admitted with acute stroke who presented to the emergency department (ED) of the study hospital within 48 hours of symptom onset before intravenous recombinant tissue plasminogen activator was approved. Prehospital delay was defined as time from symptom onset to the ED arrival. Univariate and multivariable regression analyses were conducted to evaluate factors influencing delay in ED presentation and delay in decision to seek medical help. Results— The median interval between symptom onset and decision to seek medical contact was 90 minutes; the median interval between symptom onset and ED arrival was 335 minutes. The time from symptom onset to first call for medical help accounted for 45% (95% confidence interval, 41 to 50) of the prehospital delay. Advanced age delayed the decision to seek medical help, whereas stroke severity reduced the risk for this delay. Conclusions— The time interval between symptom onset and the decision to call for medical care is far from optimal and is the underlying cause of prolonged prehospital delay. Educational efforts to reduce extent of delay are urgently needed.

Increased Oxidative Damage with Altered Antioxidative Status in Type 2 Diabetic Patients Harboring the 16189 T to C Variant of Mitochondrial DNA

Abstract: A transition of T to C at nucleotide position 16189 in mitochondrial DNA (mtDNA) has attracted biomedical researchers for its probable correlation with the development of diabetes mellitus in adult life. In diabetes, persistent hyperglycemia may cause high production of free radicals. Reactive oxygen species are thought to play a role in a variety of physiologic and pathophysiologic processes in which increased oxidative stress may play an important role in disease mechanisms. The aim of the present study was to clarify the degree of oxidative damage and plasma antioxidant status in diabetic patients and to see the potential influence of the 16189 variant of mtDNA on the oxidative status in these patients. An indicative parameter of lipid peroxidation, malondialdehyde (MDA), and total free thiols were measured from plasma samples of 165 type 2 diabetic patients with or without this variant and 168 normal subjects. Here we report an increase in the plasma levels of MDA and total thiols in type 2 diabetic patients compared with control subjects. The levels of plasma thiols in diabetic patients with the 16189 variant of mtDNA were not different from those in controls. These results suggest an increase in the oxidative damage and a compensatory higher antioxidative status in patients with type 2 diabetes. Harboring the 16189 mtDNA variant may impair the ability of a cell to respond properly to oxidative stress and oxidative damage.

Predicting 3-month Mortality Among Patients Hospitalized for First-ever Acute Ischemic Stroke

BACKGROUND The clinical course of patients with acute ischemic stroke tends to be unstable. Understanding the factors contributing to the progression of stroke is important for the appropriate management of patients. This study investigated the factors related to 3-month mortality at admission in patients with first-ever acute ischemic stroke. METHODS Patients with first-ever acute ischemic stroke consecutively admitted to a medical center in Taiwan within 48 hours after stroke onset were prospectively followed-up for 3 months. All deaths during this 3-month post-stroke period were analyzed. We evaluated only those characteristics that could be assessed at admission. Multivariate logistic regression analysis was used to identify the main predictors of 3-month stroke-related mortality. RESULTS In the 360 enrolled patients, the inhospital mortality rate was 7.8% (28 deaths), and the 3-month mortality rate was 9.7% (35 deaths). Twenty-seven deaths (77%) were stroke-related. Risk factors for mortality at 3 months included sex (odds ratio [OR], 3.18; 95% confidence interval [CI], 1.08-9.41; p=0.036), National Institutes of Health Stroke Scale (NIHSS) at admission (per unit increase: OR, 1.17; 95% CI, 1.12-1.22; p<0.001), history of cardiac disease (OR, 2.73; 95% CI, 1.04-7.16; p=0.042), and posterior circulation stroke (OR, 5.25; 95% CI, 1.92-14.36; p=0.001). CONCLUSION This study of hospital-based data on patients with first-ever acute ischemic stroke in Taiwan found that initial NIHSS, posterior circulation stroke and history of cardiac disease were risk factors for 3-month mortality.

Association of the mitochondrial DNA 16189 T to C variant with lacunar cerebral infarction: evidence from a hospital-based case-control study.

Abstract: A transition of T to C at nucleotide position 16189 in the hypervariable D‐loop region of mitochondrial DNA (mtDNA) has attracted research interest for its probable correlation with increasing insulin resistance and development of diabetes mellitus (DM) in adult life. In this article, we present our observations of the positive relationship between this variant and cerebral infarction. Six hundred and one subjects in two groups—one with cerebral infarction (307 cases), the other with no cerebral infarction (294 cases)—were recruited. Their clinical features, fasting blood sugar and insulin levels, and insulin resistance index, were recorded. Patients with cerebral infarction were further categorized into four different subgroups according to the TOAST criteria for stroke classification. The results showed the occurrence of the mtDNA 16189 variant in 34.2% of patients with cerebral infarction and in 26.5% of normal controls. The difference in the occurrence rates between the two groups was statistically significant (P= 0.041). Further studies of the occurrence rate in each stroke subgroup revealed that the variant occurred at the highest frequency in the small vessel subgroup (41.5%). The difference in occurrence rate between this subgroup and the normal controls is highly significant (P= 0.006). These results correlated well with the findings of significantly increased levels of average fasting blood insulin and a higher index of average insulin resistance in the small vessel subgroup of patients harboring this mtDNA variant. Taken together, we suggest that the mtDNA 16189 variant is a predisposing genetic factor for the development of insulin resistance and may be related to various phenotypic expressions in adult life such as development of DM and vascular pathologies involved in stroke and cardiovascular diseases.

Lack of Relation Between Severity of Stroke and Severity of Extracranial Internal Carotid Artery Lesions in Taiwanese First-Ever Ischemic Stroke Patients

Background and Purpose. The authors attempt to determine whether hemodynamically significant extracranial internal carotid artery (ICA) lesions correlate with the severity of first‐ever hemispheric ischemic stroke. Methods. Carotid duplex was used to evaluate carotid arteries. The National Institutes of Health Stroke Scale was used to describe the severity of the stroke and was stratified as follows: 1–6 = mild, 7–15 = moderate, >15 = severe. Duplex findings were categorized according to velocity criteria into <50% stenosis if ICA peak systolic velocity (PSV) (cm/s) <140 and >50% stenosis if ICA PSV >140 or ratio of ICA and common carotid artery in PSV >2. No detectable flow at ICA was considered occlusion. Stroke subtype was classified according to TOAST criteria. Results. Two hundred nineteen consecutive patients were enrolled, including 127 with mild, 65 with moderate, and 27 with severe stroke. The prevalence of ICA stenosis >50% in each group was 3.6%, 1.4%, 0.9%, respectively. Two patients in the severe group had total ICA occlusion. The overall prevalence of significant ICA lesions was 6.8%. Conclusions. There is no positive correlation of stroke severity with the severity of duplex findings, which may be due to low prevalence of significant ICA lesions or other stroke mechanisms. Most of the patients had mild stroke, and the majority had ICA stenosis <50%. Small‐vessel occlusion tended to have mild severity of stroke. Intracranial artery lesions or other factors causing stroke in Taiwanese should be investigated. Given the low incidence of significant extracranial carotid disease in symptomatic Taiwanese stroke patients, routine screening of symptomatic Taiwanese for extracranial carotid artery disease does not provide enough information to determine stroke mechanism, and transcranial Doppler should be added to the screening tests.

Association of the Mitochondrial DNA 16189 T to C Variant with Lacunar Cerebral Infarction

A transition of T to C at nucleotide position 16189 in the hypervariable D-loop region of mitochondrial DNA (mtDNA) has attracted research interest for its probable correlation with increasing insulin resistance and development of diabetes mellitus (DM) in adult life. In this article, we present our observations of the positive relationship between this variant and cerebral infarction. Six hundred and one subjects in two groups-one with cerebral infarction (307 cases), the other with no cerebral infarction (294 cases)-were recruited. Their clinical features, fasting blood sugar and insulin levels, and insulin resistance index, were recorded. Patients with cerebral infarction were further categorized into four different subgroups according to the TOAST criteria for stroke classification. The results showed the occurrence of the mtDNA 16189 variant in 34.2% of patients with cerebral infarction and in 26.5% of normal controls. The difference in the occurrence rates between the two groups was statistically significant (P = 0.041). Further studies of the occurrence rate in each stroke subgroup revealed that the variant occurred at the highest frequency in the small vessel subgroup (41.5%). The difference in occurrence rate between this subgroup and the normal controls is highly significant (P = 0.006). These results correlated well with the findings of significantly increased levels of average fasting blood insulin and a higher index of average insulin resistance in the small vessel subgroup of patients harboring this mtDNA variant. Taken together, we suggest that the mtDNA 16189 variant is a predisposing genetic factor for the development of insulin resistance and may be related to various phenotypic expressions in adult life such as development of DM and vascular pathologies involved in stroke and cardiovascular diseases.