Biomedical subjects

R C Chen

Publications and source records attributed to R C Chen.

At least 19 recordsLinked to original sources

PubMed2001

Prevalence, incidence, and mortality of PD: a door-to-door survey in Ilan county, Taiwan.

BACKGROUND: The reported prevalence and incidence rates of PD were significantly lower in China than those in Western countries. People in China and Taiwan have a similar ethnic background. OBJECTIVE: To investigate the prevalence, incidence, and mortality rate of PD in Taiwan. METHOD: The authors conducted a population-based survey using a two-stage door-to-door approach for patients aged 40 years or older in Ilan, Taiwan. Patients were diagnosed with PD by having at least two of the four cardinal signs of parkinsonism and exclusion of seconddary parkinsonism. To identify new cases of PD after the survey, patients with negative results of parkinsonism in the first stage were matched to the information on clinical diagnosis of PD from the Bureau of National Health Insurance toward the end of December 31, 1997. All cases of PD were linked to the Taiwan mortality registration to ascertain causes of deaths until December 31, 1999. RESULTS: The participation rate was 88.1% among the 11,411 contacted individuals. Thirty-seven cases of PD were identified. The age-adjusted prevalence rate of PD for all age groups was 130.1 per 100,000 population after being adjusted to the 1970 US census, assuming no cases of PD would be found among those younger than 40 years of age. Of 9972 non-PD subjects in the first screen, 15 new cases of PD were ascertained. The age-adjusted incidence rate was 10.4 per 100,000 population for all age groups. The case fatality rate of PD after a 7-year follow-up was 40.4% (21 deaths in 52 patients with PD). The relative risk of death for PD cases versus non-PD cases was 3.38 (95% CI: 2.05-4.34). The 5-year cumulative survival rate in PD cases (78.85%) was statistically lower than that in non-PD cases (92.84%). CONCLUSION: The prevalence and incidence rates of PD in Taiwan were much higher than those reported in China, but closer to those in Western countries. These results suggest that environmental factors may be more important than racial factors in the pathogenesis of PD.

Adult↗

PubMed2001

Attenuation of paraquat-induced dopaminergic toxicity on the substantia nigra by (-)-deprenyl in vivo.

(-)-Deprenyl (DEP) had been shown to slow of progression of Parkinson's disease (PD). The present study sought to determine whether DEP would attenuate the nigrostriatal system damage induced by intranigral administration of the herbicide paraquat (PQ) as a model of parkinsonism in vivo. Neurochemical and behavioral observations of Wistar rats were the focus of our study. In the neurochemical observation, the PQ injected in the rats caused dose-dependent depletion of dopamine (DA) in the ipsilateral striata. The coadministration of DEP with PQ partially increased the striatal DA level. The prediction of the striatal DA levels was calculated by regression coefficients obtained from multiple linear regression (r(2) = 0.82): DA level (% of control) = 103.34 - 9.58 PQ (nmol) + 0.79 DEP (nmol). It was demonstrated that the high dose of 20 nmol DEP could significant attenuate the PQ (5 nmol)-elicited dopaminergic toxicity (p < 0.05). In the behavioral observation, the intranigral injection of PQ into the rats caused a rotation behavior contralateral to the lesioned side in response to apomorphine administration (0.5 mg/kg, sc). This apomorphine-induced rotational behavior could also be attenuated significantly by coadministration of DEP (20 nmol) and PQ (5 nmol) compared with PQ-treated (5 nmol) animals (p < 0.05). The above observations indicate that DEP could provide a protective effect on the moderate injury elicited by PQ toxicity of the nigrostriatal dopaminergic system. DEP might be a useful therapeutic agent in treating patients with early-stage PD.

Animals↗

PubMed2001

Quantitative pathology of cutaneous nerve terminal degeneration in the human skin.

Pathological diagnosis of neuropathy has traditionally depended on ultrastructural examinations of nerve biopsy specimens, particularly for sensory neuropathies affecting unmyelinated and small-myelinated nociceptive nerves. These sensory nerves terminate in the epidermis of the skin, and the pathology of neuropathy usually begins from nerve terminals. We investigated the feasibility of diagnosing small-fiber sensory neuropathy by evaluating cutaneous innervation. Skin biopsy specimens of 3-mm in diameter were obtained from the distal leg and the distal forearm of 55 healthy controls and 35 patients with sensory neuropathy. In the healthy controls, conventional intraepidermal nerve fiber densities (IENF densities) as measured using the image analysis system in the distal forearm and in the distal leg were correlated (r=0.55, P<0.0001), with significantly higher values in the distal forearm than in the distal leg (17.07+/-6.51 vs 12.92+/-5.33 fibers/mm, P<0.001). Compared to IENF densities of healthy controls, these values of neuropathic patients were significantly reduced in the distal forearm (5.82+/-6.50 fibers/mm, P<0.01) and in the distal leg (2.40+/-2.30, P<0.001). We further explored the possibility of quantifying skin innervation by counting "ocular intraepidermal nerve fiber density" (ocular nerve fiber density) with no aid of an image analysis system. This was based on the fact that the epidermal length on specifically defined sections was very close to the predicted epidermal length of 3 mm, the diameter of skin punches (P=0.14). Ocular nerve fiber densities were significantly correlated with IENF densities as measured by the image analysis system (r=0.99, P<0.0001). Dermal nerve fibers of neuropathic patients either disappeared or became degenerated. These findings were consistent with the notion of early terminal degeneration in neuropathy, and will facilitate quantitative interpretation of epidermal innervation in human neuropathy.

Adult↗

PubMed2001

Seizure frequency affects event-related potentials (P300) in epilepsy.

To analyse the effect of epilepsy an P300 event-related potentials we studied 27 patients with idiopathic generalized epilepsy (IGE), 13 patients with temporal lobe epilepsy (TLE) and 60 normal controls. The prolongation of P300 latencies was highly cor related with increasing age in controls but not epileptic patients. The age-corrected P300 latency used in this study was actual P300 latency-predicted P300 latency (predicted P300 (msec)=306.20+0.79 age, P=0.001, R2=0.32). By using ANOVA analysis, the age-corrected latencies of P300 were significantly longer in TLE patients (19.72+/-47.82 msec, mean+/-SD) than in IGE patients (10.97+/-36.97 msec) and controls (0.23+/-20.28 msec). Likewise, significantly prolonged P300 latencies were seen in the epileptic patients with a seizure frequency more than 400 times (37.21+/-47.50 msec). The multivariate-adjusted odds ratio for those who had TLE was 10.97 (95% CI=3.99 - 30.14 ) in the prolonged latencies of P300 compared with that of IGE patients. The odds ratio of longer latencies of P300 was 7.43 (95% CI=2.75 - 20.08) among those who had a high seizure frequency (> or =400 times) compared with those who had a low seizure frequency. No interaction between TLE and high frequency of attacks was found. The age at onset of seizure and duration of illness was not associated with P300 latency prolongation. From the above results, we might infer that the seizure type of TLE and a high frequency of seizure are two major independent precipitate factors for abnormal latencies of P300 in the epileptic patients.

Adult↗

PubMed2001

Vertebral bone marrow perfusion evaluated with dynamic contrast-enhanced MR imaging: significance of aging and sex.

PURPOSE: To investigate blood perfusion of nonfractured, normal-appearing vertebral bodies with regard to age and sex. MATERIALS AND METHODS: Dynamic magnetic resonance imaging (160 images obtained in 80 seconds) was performed from T10 to L5 in 66 patients. Patients were assigned to three groups: group 1, those 50 years or younger without compression fracture; group 2, those older than 50 years without compression fracture; or group 3, those older than 50 years with compression fracture. Peak enhancement percentage and enhancement slope were determined from the time-intensity curve of normal (nonfractured) vertebral body. Comparisons were made between groups, and the effect of age and sex interaction was analyzed. RESULTS: Higher peak enhancement percentage was demonstrated for group 1 compared with group 2 (58.21 +/- 44.65 [SD] vs 21.88 +/- 14.77, P <.005). Group 1 women revealed a higher enhancement percentage compared with group 1 men (87.17 +/- 54.13 vs 38.16 +/- 21.69, P <.05), which significantly decreased in those older than 50 years (from 87.17 +/- 54.13 to 17.98 +/- 13.80, P <.005). For men, this decrease in those older than 50 years was not as pronounced (from 38.16 +/- 21.69 to 25.38 +/- 15.43, P >.05). Presence of compression fracture at other levels of the spine (group 3) was not associated with a different enhancement percentage for normal vertebrae. CONCLUSION: Rate of vertebral bone marrow perfusion revealed a significant decrease in subjects older than 50 years. Women demonstrated a higher marrow perfusion rate than men younger than 50 years and a more marked decrease than men older than 50 years.

Adult↗

PubMed2001

Comparison of Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for measurement of cardiac troponin I.

Myocardial infarction is a common cause of morbidity and mortality in patients with chest pain. The presence of human cardiac troponin I (cTnI) in serum is considered to be a highly specific biochemical marker of acute myocardial infarction. In this study we compare the performances of the Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for the measurement of cTnI. The first two methods use a fluorogenic enzyme-linked immunoassay. whereas the last two use chemiluminescent immunometric assays. All procedures are completely automated. Total percentage coefficients of variation using pooled sera ranged from 5.9 to 6.5% for the AxSYM, 14.4 to 25.6% for the Opus, 6.9 to 9.8% for the Immulite and 4.5 to 5.2% for the Vitros ECi method. The closest correlation between methods, obtained from 120 fresh serum samples, was observed between the Vitros ECi and the Immulite methods, with r=0.99, and the regression line was Immulite cTnI 1.505 (95% confidence interval 1.474-1.536) x Vitros cTnI--0.154 (-0.702 to 0.394). Receiver operating characteristic curves were nearly identical for all assays, and the areas under the curves were 0.972, 0.927, 0.967 and 0.969 for the AxSYM, Opus, Immulite and Vitros ECi methods, respectively. There was a significant difference between the AxSYM and Opus methods (P= 0.036).

Biomarkers↗

PubMed2001

Paget's disease of the bone: a case report.

Paget's disease of bone is rare in Asia. We report a case of Paget's disease in a 58-year-old Taiwanese man who was admitted with a 3-month history of bilateral numbness in the buttock region. Laboratory data disclosed an elevated serum alkaline phosphatase level (510 U/L). Plain radiographs of the lumbar spine showed generalized increased density at the third lumbar vertebra, associated with cortical thickening, loss of cortico-cancellous definition, and increased anteroposterior diameter. The T1-weighted magnetic resonance image of the lumbar spine showed diffuse, heterogeneous low signal intensity at the third lumbar vertebral body, pedicle, laminae, and spinal process; these areas showed mixed high and low signal intensity on the T2-weighted image. Technetium-99m bone scan revealed abnormal uptake in the involved vertebra. Histologic examination of the third lumbar spinal process confirmed the diagnosis of Paget's disease of bone. The patient remained well during a follow-up period of 6 months.

Humans↗

PubMed2001

Erythrocyte Lewis antigen phenotypes of dyspeptic patients in Taiwan--correlattion of host factor with Helicobacter pylori infection.

BACKGROUND AND AIMS: Because of the molecular mimicry between Helicobacter pylori lipopolysaccharide and host Lewis blood-group antigens, Lewis antigen may mediate specific H. pylori binding to surface epithelial cells in gastric mucosa. We, therefore, tested whether different Lewis antigen phenotypes have different prevalence rates of H. pylori infection, and determined the specific H. pylori-related disease entities or histologic features. METHOD: A total of 342 dyspeptic patients without previous anti-H. pylori therapy were enrolled after endoscopy. The Lewis phenotypes, defined as Le(a-b-), Le(a-b+), Le(a+b-), and Le(a+b+) subtypes, were determined from the expression or absence of Lewis antigens (Le(a) and Le(b)) on erythrocytes in each patient using monoclonal antibodies. The H. pylori-specific gastric histology was evaluated using the updated Sydney's system. RESULTS: Of 342 patients, 233 (68.1%) had H. pylori infection. The H. pylori infection rates were significantly higher in patients with Lewis phenotypes Le(a+b-) and Le(a+b+) (p < 0.05). Patients expressing the Le(a) antigen had a higher H. pylori infection rate than those without the Le(a) antigen (80.8 vs 64%, p < 0.005). In H. pylori-infected patients, patients expressing Le(b) antigen had a lower rate of gastroduodenal ulcers than those without Le(b) antigen (46.9 vs 61.4%, p < 0.05). H. pylori-positive patients who expressed the Le(b) antigen had higher bacterial density and inflammation severity in the gastric cardia than those who did not. Patients who expressed the Le(a) antigen had lower bacterial density, less chronic inflammation severity, and lower frequency of lymphoid follicles in the gastric cardia than those who did not (p < 0.05). CONCLUSION: The erythrocyte Lewis phenotype can be a significant host factor related to susceptibility, different histologic patterns, and clinical outcomes of H. pylori infection in Taiwan.

Dyspepsia↗

PubMed2000

Effect of MAO-B inhibitors on MPP+ toxicity in Vivo.

l-Deprenyl (Selegiline), a selective and irreversible type B monoamine oxidase inhibitor, has been used as an adjunct to levodopa therapy in Parkinson's disease. Recently, it is proposed as a putative neuroprotective agent in delaying the progression of cell death based on its capability of reducing the oxidative stress derived from the MAO-B dependent metabolism of dopamine, and blocking the development of MPTP-parkinsonism. However, a variety of experimental models suggest that l-deprenyl provides neuroprotection through multiple modes of mechanism other than the inhibition of MAO-B. We have previously shown that l-deprenyl protects midbrain dopamine neurons from MPP+ toxicity by a novel antioxidant effect. In the present study we examined whether the protection against MPP+ toxicity is also shared by other reversible or irreversible MAO-B inhibitors including (+)-deprenyl, Ro16-6491 and pargyline. Our data show that non of these MAO-B inhibitors changes the dopamine loss in the striatum induced by intranigral injection of MPP+. Our result suggests that l-deprenyl may possess a unique neuroprotective action on nigral neuron against MPP+ toxicity independent of the MAO-B inhibition.

1-Methyl-4-phenylpyridinium↗

PubMed2000

Imaging in the diagnosis and follow-up evaluation of vertebral artery dissection.

The purpose of this report is to discuss the value of ultrasonographic examination in the diagnosis and follow-up evaluation of vertebral artery dissection. We collected data on 8 patients with 11 pathologic vessels: 9 were affected intracranially and 6 were affected extracranially. Four vessels were affected in both intracranial and extracranial segments. Extracranial color-flow duplex sonography could detect abnormalities in every extracranial vertebral artery dissection. Most abnormal findings were non-specific, including severely reduced flow, absence of flow, and absence of diastolic flow. A specific finding (intramural hematoma) was noted in one artery. Abnormal transcranial color-coded sonographic findings included absence of flow, reduced velocity and reversed flow direction. Three intracranial dissecting arteries showed normal findings on transcranial color-coded sonography. Ultrasonographic follow-up study revealed evidence of improvement; this was noted almost exclusively in the extracranial segments of the vertebral artery but infrequently in the intracranial segment. Extracranial color-flow duplex sonography is sensitive in the detection of extracranial vertebral artery dissection, both in initial diagnosis and in follow-up evaluation.

Adult↗

PubMed2000

Monitoring of the levodopa concentration-response relationship in Parkinson's disease.

Motor fluctuations and abnormal involuntary movements are common complications encountered in advanced Parkinson's disease (PD) patients with long-term levodopa therapy. Monitoring of plasma levodopa concentrations and clinical effects has been reported to benefit the management of these complications. However, to our knowledge, there is no data available in Taiwan concerning the correlation between the plasma levodopa levels and motor fluctuations. In this study, we developed the laboratory methodology for plasma levodopa determination by using the aluminum extraction procedure and HPLC-ED. Serial blood samples and motor scores were obtained from 7 PD patients, and the correlation between plasma levodopa levels and motor responses were studied individually. In three patients with wearing-off phenomenon, plasma levodopa concentrations are compatible with the clinical "on" and "off" states. In the other four patients with complex fluctuating responses, their levodopa dosages were adjusted by the results of monitoring. Better motor responses were achieved by optimization of the levodopa pharmacokinetics in these patients. Our preliminary data suggest that simultaneous monitoring of plasma levodopa concentrations and clinical effects might be helpful to improve the therapeutic strategy in some of the parkinsonian patients with fluctuating responses to levodopa.

Adult↗

PubMed1999

Perceived inspiratory difficulty during inspiratory threshold and hyperinflationary loadings.

Dynamic hyperinflation loads the inspiratory muscles by increasing end-expiratory lung volume (EELV) and imposing intrinsic positive end-expiratory pressure (PEEPi), the latter behaving as an inspiratory threshold load (ITL). The major purpose of this study was to describe the independent effects of the imposed ITL and changes in operating lung volume on the perception of inspiratory difficulty. In eight healthy subjects, independent increases in EELV and ITL were induced by continuous positive airway pressure (CPAP) and external ITL applications, respectively; increase in both EELV and PEEPi (thus the imposed ITL) was induced by application of positive end-expiratory pressure (PEEP). The perceived inspiratory difficulty increased significantly when either EELV or ITL was increased, and was always greater during combined increase in EELV and the imposed ITL (during PEEP) than when either factor was increased independently, suggesting that the imposed ITL and EELV each contribute independently to inspiratory difficulty. Inspiratory difficulty of each subject under all conditions was then fitted into a step-forward multiple regression model. The imposed ITL was a significant contributor to inspiratory difficulty in all subjects and was the first parameter to be selected in six of the eight subjects. When the results of all the subjects were pooled, the imposed ITL alone explained 40% of variations in inspiratory difficulty. Adding the change in end-inspiratory lung volume (DeltaEILV) to the model explained an additional 24% of variations in inspiratory difficulty. The coefficients (slopes) of the imposed ITL and DeltaEILV were 0.21 +/- 0.02 cm H2O-1 and 0.051 +/- 0.006 %IC-1, respectively. It is concluded that under our experimental conditions, the imposed ITL is a better predictor for explaining the variability of the perceived inspiratory difficulty than the operating lung volume.

Adult↗

PubMed1998

Subtypes and case-fatality rates of stroke: a hospital-based stroke registry in Taiwan (SCAN-IV).

Stroke data bank can afford important information regarding risk factors, pathogenesis, prognosis, etc. By means of hospital-based stroke registry, we investigated the risk factors and case-fatality rates in different types of stroke and transient ischemic attack (TIA) patients at the National Taiwan University Hospital in 1995. After excluding ineligible patients, 995 patients aged 1-98 years (575 men and 420 women) were recruited. Men predominated in all age groups for stroke and TIA in general except for cerebral hemorrhage (CH) in patients aged < 35 years and subarachnoid hemorrhage (SAH) in patients aged > or = 45 years. Of these, 676 (67.9%), 41 (4.1%), 228 (22.9%) and 50 (5%) patients were classified in the categories of cerebral infarction (CI), TIA, CH and SAH, respectively. The CI/CH ratio was 2.96. Hypertension remained one of the most important risk factors for CI, CH and TIA patients. Severe extracranial carotid artery stenosis (> or = 50%) was found in 12% of the CI patients and 27% of the TIA patients, but not found in the CH and SAH patients. Of these patients, the 30-day case-fatality rate was 10.9%, highest in SAH (30%), followed by CH (24.1%) and CI (5.6%). There were 41 in-hospital stroke patients who had significantly higher case-fatality rates than the other stroke patients (P<0.001 for all stroke, CI and CH patients by chi2 test). As compared to the previous stroke registries in Taiwan, there is a secular trend of increasing CI/CH ratios. These findings in Taiwan were compared with those in other populations, including other Asian, Caucasian and black populations. The CI/CH ratios in Asian populations, including Chinese, Japanese and Korean, were much lower than those in Caucasian and black populations. Dietary, environmental and genetic factors probably play important roles in these differences.

Adolescent↗

PubMed1998

Carbon dioxide enhanced ultrasonography of hepatic haemangiomas.

The purpose of this study was to characterize the imaging manifestations of carbon dioxide enhanced ultrasonography (CO2US) in hepatic haemangiomas. CO2US was performed for 52 haemangiomas in 25 patients and for 352 various hepatic nodules in 192 patients. Characteristic enhancement patterns for hepatic haemangiomas were noted. All 39 large haemangiomas (> 1 cm) demonstrated peripheral nodular enhancement in the early and parenchymal phases associated with delayed washout character (> 30 min). Centripetal fill-in of CO2 was noted in 82.1% of large haemangiomas. Two enhancing patterns were noted in 13 small haemangiomas (< 1 cm): peripheral nodular (69.2%) and homogeneous (30.8%). Delayed washout was also noted in all small haemangiomas. Centripetal fill-in of CO2 was hard to define in small haemangiomas. None of the other 352 hepatic nodules had the same imaging features. In conclusion we found that CO2US is valuable in differentiating hepatic haemangiomas from other liver tumours in clinically doubtful cases.

Adult↗

PubMed1998

Intra-arterial carbon dioxide-enhanced ultrasonogram of hepatocellular carcinoma treated by transcatheter arterial embolization and percutaneous ethanol injection therapy.

The purpose of this study was to investigate the value of carbon dioxide-enhanced ultrasonography (CO2-US) in the evaluation of viable hepatocellular carcinomas (HCC) which were treated by transcatheter arterial embolization (TAE), percutaneous ethanol injection (PEI), or a combination treatment (TAE and PEI). Forty-one patients with 66 HCC were included in the study. They underwent CO2-US and angiography were performed in all tumours after they were treated by TAE, PEI or a combination treatment. Forty-six tumours were positively enhanced by CO2-US and 40 of them were positive by angiography. These 46 tumours were proved to be viable tumours either by biopsy or by follow-up studies. The positive predictive value was 100% for CO2-US and 87.8% in angiography. Twenty tumours were negative by CO2-US and these were also negative by angiography. Carbon dioxide-enhanced ultrasonography is a more reliable method for detecting the viable portion of the treated HCC compared with conventional angiography.

Adult↗

PubMed1998

Introduction to a new inspiratory threshold loading device.

Inspiratory threshold loading is an important tool in assessing inspiratory muscle function and has been widely used in studies of respiratory mechanics. A simple system was designed to provide a pure and precise inspiratory threshold load. The inspiratory threshold loading system comprises a flow generator attached via a pressure chamber, to the inspiratory port of a Hans-Rudolph valve. By limiting the circulation of air generated by the flow generator between the room and the pressure chamber, different levels of negative pressure are produced in the pressure chamber and applied to the inspiratory valve. An inspiratory pressure equal to the negative pressure in the chamber has to be generated to open the inspiratory valve for flow. The system was tested in four subjects by measuring mouth pressure (Pm), threshold pressure (Pth) and valve resistance (R). The Pm at the beginning of inspiratory flow was defined as the opening pressure (Pop). The Pth was constant throughout inspiration. Pop was linearly related to Pth (p<0.0001), with slopes within 2% of identity and intercepts within +/-0.2 cmH2O. R was between 0.7-1.1 cmH2O x L(-1) x s(-1) under all conditions and was independent of both Pth (p=0.76) and inspiratory flow (p=0.24). The results demonstrate that this system can provide a constant inspiratory threshold load throughout inspiration with little flow resistance, and is therefore ideal for respiratory studies.

Adult↗

PubMed1997

Carbamazepine inhibition of neuronal Na+ currents: quantitative distinction from phenytoin and possible therapeutic implications.

Carbamazepine and phenytoin, two of the most commonly prescribed antiepileptic drugs, have been proposed to share a similar mechanism of action by use-dependent inhibition of Na+ channels. The proposed similar mechanism of action, however, cannot explain the common clinical experiences that the two drugs are different; in some patients, one drug may be more effective than the other. This may occur even when optimal therapeutic concentrations are reached with both medications in plasma or the cerebrospinal fluid. In this study, we show that the action of the two drugs on Na+ channels are quantitatively very different. The affinity between inactivated Na+ channels and carbamazepine (apparent dissociation constant approximately 25 microM) is approximately 3 times lower than that of phenytoin, yet the binding rate constant of carbamazepine onto the inactivated Na+ channels is approximately 38,000 M(-1)/sec(-1), or approximately 5 times faster than that of phenytoin. It is speculated that carbamazepine may be more effective than phenytoin in treating seizures whose ictal depolarization shift is relatively short, whereas a better response to phenytoin may imply abnormal discharges characterized by more prolonged depolarization.

Animals↗

PubMed1997

Subtypes of ischemic stroke. A hospital-based stroke registry in Taiwan (SCAN-IV).

BACKGROUND AND PURPOSE: To better understand the clinical pattern and further elucidate the risk factors and outcome in different subtypes of cerebral infarction (CI) of the Chinese in Taiwan, we analyzed the National Taiwan University Hospital Stroke Registry in 1995 and performed an ethnic comparison with similar data banks. METHODS: From the National Taiwan University Hospital Stroke Registry in 1995, 676 patients (383 men and 293 women; mean age, 64.9 years; SD, 13.8 years; range, 1 to 98 years) with CI were recruited for this analysis. CI was classified into five subtypes based on clinical manifestations, ultrasonographic studies, and neuroimaging findings: large-artery atherosclerosis, lacunae, cardioembolism, other less common determined causes, and undetermined cause. Vascular risk factors, extracranial carotid artery atherosclerosis, and 30-day case-fatality rates were investigated in each subtype of CI. RESULTS: Of all CI patients, 17%, 29%, 20%, 6%, and 29% were classified as large-artery atherosclerosis, lacunae, cardioembolism, other determined causes, and undetermined cause subtypes, respectively. The present results were compared with those from eight similar Western stroke registries. The relative incidence of lacunar CI in Chinese patients was more common, but large-artery atherosclerotic CI was less common than in whites. Hypertension was frequently seen in CI patients, especially in those with lacunae (85%) and large-artery atherosclerosis (69%). Patients with cardioembolism had a higher percentage of atrial fibrillation (69%), left ventricular hypertrophy, and ischemic heart disease than the other patients. Patients with large-artery atherosclerosis had more vascular risk factors, such as hypertension, diabetes mellitus, smoking, and carotid stenosis. Cardioembolic patients had higher case-fatality rates than other CI patients. Of the cardioembolic patients, 17.3% and 21.8% died within 30 days and during hospitalization, respectively. CONCLUSIONS: The proportion of CI subtypes varied in different stroke registries. This may be partly due to applied classification criteria and racial-ethnic differences. Awareness of the risk factors and outcome in each subtype of stroke may afford further insights into the surveillance and treatment of cerebrovascular disease.

Adolescent↗