Identifying Target Risk Factors Using Population Attributable Risks of Ischemic Stroke by Age and Sex

Background and Purpose

Estimating age- and sex-specific population attributable risks (PARs) of major risk factors for stroke may be a useful strategy to identify risk factors for targeting preventive strategies.

Methods

For this case-control matched study, consecutive patients aged 18-90 years and admitted to nine nationwide hospitals with acute ischemic stroke between December 2008 and June 2010, were enrolled as cases. Controls, individually matched by age and sex, were chosen from the 4th Korean National Health & Nutrition Examination Survey (2008-2010). Based on odds ratios and prevalence, standardized according to the age and sex structure of the Korean population, PARs of major risk factors were estimated according to age (young, ≤ 45; middle-aged, 46-65; and elderly, ≥ 66 years) and sex subgroups.

Results

In 4,743 matched case-control sets, smoking (PAR, 45.1%) was the greatest contributing risk factor in young men, followed by hypertension (28.5%). In middle-aged men, the greatest contributing factors were smoking (37.4%), hypertension (22.7%), and diabetes (14.6%), whereas in women the greatest factors were hypertension (22.7%) and stroke history (10.6%). In the elderly, hypertension was the leading factor in men (23.7%) and women (23.4%). Other noticeable factors were stroke history (men, 19.7%; women, 17.3%) and diabetes (men, 12.5%; women, 15.1%). In young women, risk factors with a PAR greater than 10% were not found.

Conclusions

Smoking cessation in young people and hypertension and diabetes control in older people may be effective in reducing the burden of stroke on the population. In the elderly, secondary prevention could also be emphasized.

Intravenous Tissue Plasminogen Activator Improves the Outcome in Very Elderly Korean Patients with Acute Ischemic Stroke

Background and Purpose

In a recent pooled analysis of randomized clinical trials (RCTs), intravenous tissue plasminogen activator (TPA) improves the outcome in patients aged ≥80 years. However, it is uncertain whether the findings are applicable to clinical practice in Asian populations.

Methods

From a multicenter stroke registry database of Korea, we identified patients with acute ischemic stroke who were aged ≥ 80 years. Using multivariable analysis and propensity score (PS)-matched analyses, we assessed the effectiveness and safety of intravenous TPA within 4.5 hours.

Results

Among 2,334 patients who met the eligible criteria, 236 were treated with intravenous TPA (mean age, 83±5; median NIHSS, 13 [IQR, 8-17]). At discharge, the TPA group compared to the no-TPA group had a favorable shift on the modified Rankin Scale (mRS) score (multivariable analysis, OR [95% CI], 1.51 [1.17-1.96], P=0.002; PS-matched analysis, 1.54 [1.17-2.04], P=0.002) and was more likely to achieve mRS 0-1 outcome (multivariable analysis, 2.00 [1.32-3.03], P=0.001; PS-matched analysis, 1.59 [1.04-2.42], P=0.032). TPA treatment was associated with an increased risk of symptomatic intracranial hemorrhage (multivariable analysis, 5.45 [2.80-10.59], P<0.001; PS-matched analysis, 4.52 [2.24-9.13], P<0.001), but did not increase the in-hospital mortality (multivariable analysis, 0.86 [0.50-1.48], P=0.58; PS-matched analysis, 0.88 [0.52-1.47], P=0.61).

Conclusions

In the setting of clinical practice, intravenous TPA within 4.5 hours improved the functional outcome despite an increased risk of symptomatic intracranial hemorrhage in very elderly Korean patients. The findings, consistent with those from pooled analysis of RCTs, strongly support the use of TPA for this population.

Case characteristics, hyperacute treatment, and outcome information from the clinical research center for stroke-fifth division registry in South Korea

Characteristics of stroke cases, acute stroke care, and outcomes after stroke differ according to geographical and cultural background. To provide epidemiological and clinical data on stroke care in South Korea, we analyzed a prospective multicenter clinical stroke registry, the Clinical Research Center for Stroke-Fifth Division (CRCS-5). Patients were 58% male with a mean age of 67.2±12.9 years and median National Institutes of Health Stroke Scale score of 3 [1-8] points. Over the 6 years of operation, temporal trends were documented including increasing utilization of recanalization treatment with shorter onset-to-arrival delay and decremental length of stay. Acute recanalization treatment was performed in 12.7% of cases with endovascular treatment utilized in 36%, but the proportion of endovascular recanalization varied across centers. Door-to-IV alteplase delay had a median of 45 [33-68] min. The rate of symptomatic hemorrhagic transformation (HT) was 7%, and that of any HT was 27% among recanalization-treated cases. Early neurological deterioration occurred in 15% of cases and were associated with longer length of stay and poorer 3-month outcomes. The proportion of mRS scores of 0-1 was 42% on discharge, 50% at 3 months, and 55% at 1 year after the index stroke. Recurrent stroke up to 1 year occurred in 4.5% of patients; the rate was higher among older individuals and those with neurologically severe deficits. The above findings will be compared with other Asian and US registry data in this article.

Recombinant factor IX (BAX326) in previously treated paediatric patients with haemophilia B: a prospective clinical trial

A newly developed recombinant factor IX (BAX326(1) ) was investigated for prophylactic use in paediatric patients aged <12 years with severe (FIX level <1%) or moderately severe (FIX level 1-2%) haemophilia B. The aim of this prospective clinical trial was to assess the safety, haemostatic efficacy and pharmacokinetic profile of BAX326 in previously treated paediatric patients. BAX326 was administered as prophylaxis twice a week for a period of 6 months, and on demand for treatment of bleeds. Safety was assessed by the occurrence of related AEs, thrombotic events and immunologic assessments. Efficacy was evaluated by annualized bleeding rate (ABR), and by treatment response rating (excellent, good, fair, none). PK was assessed over 72 h. None of the 23 treated paediatric subjects had treatment-related SAEs or AEs. There were no thrombotic events, inhibitory or specific binding antibodies against FIX, rFurin or CHO protein. Twenty-six bleeds (19 non-joint vs. 7 joint bleeds) occurred (mean ABR 2.7 ± 3.14, median 2.0), of which 23 were injury-related. Twenty subjects (87%) did not experience any bleeds of spontaneous aetiology. Haemostatic efficacy of BAX326 was excellent or good for >96% of bleeds (100% of minor, 88.9% of moderate and 100% of major bleeds); the majority (88.5%) resolved after 1-2 infusions. Longer T1/2 and lower IR were observed in younger children (<6 years) compared to those aged 6 to 12 years. BAX326 administered as prophylactic treatment as well as for controlling bleeds is efficacious and safe in paediatric patients aged <12 years with haemophilia B.

Grading and interpretation of white matter hyperintensities using statistical maps

BACKGROUND AND PURPOSE

We aimed to generate rigorous graphical and statistical reference data based on volumetric measurements for assessing the relative severity of white matter hyperintensities (WMHs) in patients with stroke.

METHODS

We prospectively mapped WMHs from 2699 patients with first-ever ischemic stroke (mean age=66.8±13.0 years) enrolled consecutively from 11 nationwide stroke centers, from patient (fluid-attenuated-inversion-recovery) MRIs onto a standard brain template set. Using multivariable analyses, we assessed the impact of major (age/hypertension) and minor risk factors on WMH variability.

RESULTS

We have produced a large reference data library showing the location and quantity of WMHs as topographical frequency-volume maps. This easy-to-use graphical reference data set allows the quantitative estimation of the severity of WMH as a percentile rank score. For all patients (median age=69 years), multivariable analysis showed that age, hypertension, atrial fibrillation, and left ventricular hypertrophy were independently associated with increasing WMH (0-9.4%, median=0.6%, of the measured brain volume). For younger (≤69) hypertensives (n=819), age and left ventricular hypertrophy were positively associated with WMH. For older (≥70) hypertensives (n=944), age and cholesterol had positive relationships with WMH, whereas diabetes mellitus, hyperlipidemia, and atrial fibrillation had negative relationships with WMH. For younger nonhypertensives (n=578), age and diabetes mellitus were positively related to WMH. For older nonhypertensives (n=328), only age was positively associated with WMH.

CONCLUSIONS

We have generated a novel graphical WMH grading (Kim statistical WMH scoring) system, correlated to risk factors and adjusted for age/hypertension. Further studies are required to confirm whether the combined data set allows grading of WMH burden in individual patients and a tailored patient-specific interpretation in ischemic stroke-related clinical practice.

Internet-based control recruitment for a case-control study of major risk factors for stroke in Korea: lessons from the experience

BACKGROUND

This study aimed to estimate the population-attributable risks (PARs) of 9 major risk factors for stroke in Korea through a case-control study and to test the feasibility and validity of internet-based control recruitment.

METHODS

From April 2008 to September 2009, controls were enrolled via internet after providing consent for participation through a web-based survey. The cases included patients who were admitted to the participating centers due to acute stroke or transient ischemic attack within 7 days of onset during the study period. Each control was age- and sex-matched with 2 cases. Adjusted odd ratios, age-standardized prevalence, and PARs were estimated for the 9 major risk factors using the prevalence of risk factors in the control group and the age and sex characteristics from Korea's national census data.

RESULTS

In total, 1041 controls were matched to 2082 stroke cases. Because of a shortage of elderly controls in the internet-based recruitment, 248 controls were recruited off-line. The PARs were 23.44%, 10.95%, 51.32%, and 6.35% for hypertension, diabetes, smoking, and stroke history, respectively. Hypercholesterolemia, atrial fibrillation, obesity, coronary heart disease, and a family history of stroke were not associated with stroke. Comparison with education and religion of the control group with that mentioned in the national census data showed a notable difference.

CONCLUSIONS

The study results imply that internet-based control recruitment for a case-control study requires careful selection of risk factors with high self-awareness and effective strategies to facilitate the recruitment of elderly participants.

Abstract 72: Comparative Effectiveness of Intravenous Thrombolysis in patients with Mild Ischemic Stroke

Background: One third of patients with initially mild strokes have unfavorable outcome, and the efficacy of intravenous thrombolysis (IVT) in those patients has not proven. This study aimed to evaluate the comparative effectiveness of IVT over no thrombolysis in patients with mild ischemic stroke presenting within 4.5 hours of onset.

Methods: From a multicenter prospective stroke registry database, we identified acute ischemic stroke patients (1) who were aged 18 years or more, (2) whose neuroimaging confirmed relevant acute ischemic lesions, (3) who were presented within 4.5 hours of onset, and (4) whose initial NIHSS scores were 5 points or less. Matching and inverse probability of treatment weighting (IPTW) by propensity score (PS) were used to remove baseline imbalance between the IVT and no treatment groups. Further adjustments for potential confounders were made in the IPTW analysis. The adjusted odds ratios (ORs) and their 95% confidence intervals (CIs) of IVT compared to no treatment were calculated for 3-month modified Rankin Scale (mRS) 0-1 (primary efficacy outcome), the full distribution of mRS scores (sedoncary efficacy outcome, by an ordinal logistic regression analysis), and symptomatic hemorrhagic transformation (sHT, safety outcome).

Results: Between April 2008 and May 2012, 13,117 stroke patients were hospitalized to the 12 participating centers. Among them, 1,386 subjects met the eligibility criteria, and 194 (14.0%) were treated with IVT. The proportions of 3-month mRS 0-1 were not different between the IVT and no treatment groups (71% vs. 75%, p=0.18), but those of sHT were different (4.1% vs. 0.5%, p<0.001).

The adjusted ORs (95% CIs, p values) were 1.46 (0.95-2.25, 0.08) by PS-matching and 1.47 (0.77-2.82, 0.24) by IPTW for 3-month mRS 0-1; 1.05 (0.73-1.49, 0.80) by PS-matching and 1.09 (0.65-1.81, 0.75) for an increment of 3-month mRS score; and 7.47 (1.52-36.64, 0.01) by PS-matching and 3.85 (0.82-18.06, 0.09) by IPTW for sHT.

Conclusion: This comparative effectiveness analysis based on the large multicenter stroke registry database failed to prove the superiority of intravenous thrombolysis over no treatment in patients with mild ischemic stroke.

Abstract 65: Effect of Prestroke Statin Use on Stroke Severity and Early Functional Recovery

Background: Experimental studies suggest that prestroke statin treatment has dual effect of neuroprotection during ischemia and neurorestoration after ischemic injury. However, human clinical stroke studies of small to modest sample sizes have shown inconsistent results regarding these effects.

Methods: We analyzed the Clinical Research Center for Stroke-5 data set for patients hospitalized with acute ischemic stroke in 12 academic hospitals between April 1, 2008 and January 31, 2012. Primary endpoint was the initial stroke severity as measured by the National Institutes of Health Stroke Scale (NIHSS) score. Secondary endpoints were mRS 0-2 proportion and overall distribution of mRS outcomes at discharge. Propensity score (PS) analysis were used to adjust baseline characteristics between statin users and non-users in addition to multivariable analyses.

Results: Among 8,340 patients included in this study (age, 67±13 years; men, 59.6%; initial median NIHSS score [interquartile range, IQR], 3 [2-7]), 964 patients (11.6%) were taking statins before the index stroke. Prestroke statin users had significantly lesser initial NIHSS score than that of non-users (unadjusted mean [95% CI], 4.6 [4.3-4.9] versus 5.4[5.3-5.6], p <0.0001; median [IQR]), 3 (IQR, 1-6) versus 3 (IQR, 2-7) , p <0.0001).The difference remained significant after adjustment for covariates (adjusted mean, 6.0 [5.5-6.5] versus 6.6 [6.1-7.0]; p=0.0062) as well as PS-matched cohort (adjusted mean, 4.8[4.3-5.2] versus 5.4[5.1-5.7], p=0.0298). After adjusting for covariates including initial NIHSS score, statin users had more frequent mRS 0-2 outcome (adjusted OR [95% CI], 1.50 [1.21-1.86]; p=0.0002) and greater favorable shift on the mRS score at discharge than those of non-users (adjusted OR [95% CI], 1.26 [1.08-1.48]; p=0.003). In PS-matched cohort, similar associations were also found for dichotomized outcomes (adjusted OR [95% CI], 1.55 [1.22-1.97]; p=0.0003) and for ordinal outcomes (adjusted OR [95% CI], 1.28 [1.07-1.52]; p=0.0058).

Conclusions: Prestroke statin use was independently associated with lesser stroke severity at presentation and better early functional outcome, suggesting dual effect of neuroprotection and neurorestoration in human clinical strokes.

Greater stroke severity predominates over all other factors for the worse outcome of cardioembolic stroke

BACKGROUND

Cardioembolic (CE) strokes are more disabling and more fatal than non-CE strokes. Multiple prognostic factors have been recognized, but the magnitude of their relative contributions has not been well explored.

METHODS

Using a prospective stroke outcome database, we compared the 3-month outcomes of CE and non-CE strokes. We assessed the relative contribution of each prognostic factor of initial stroke severity, poststroke complications, and baseline characteristics with multivariable analyses and model fitness improvement using -2 log-likelihood and Nagelkerke R2.

RESULTS

This study included 1233 patients with acute ischemic stroke: 193 CE strokes and 1040 non-CE strokes. Compared with the non-CE group, CE group had less modified Rankin Scale (mRS) 0-2 outcomes (47.2% versus 68.5%; odds ratio [95% confidence interval], .41 [.30-.56]), less mRS 0-1 outcomes (33.7% versus 53.5%; .44 [.32-.61]), more mRS 5-6 outcomes (32.1% versus 10.9%; 3.88 [2.71-5.56]), and higher mortality (19.2% versus 5.2%; 4.33 [2.76-6.80]) at 3 months. When adjusting either baseline characteristics or poststroke complications, the outcome differences between the 2 groups remained significant. However, adjusting initial National Institute of Health Stroke Scale (NIHSS) score alone abolished all outcome differences except for mortality. For mRS 0-2 outcomes, the decrement of -2 log-likelihood and the Nagelkerke R2 of the model adjusting initial NIHSS score alone approached 70.2% and 76.7% of the fully adjusting model.

CONCLUSION

Greater stroke severity predominates over all other factors for the worse outcome of CE stroke. Primary prevention and more efficient acute therapy for stroke victims should be given top priorities to reduce the burden of CE strokes.

Abstract WP400: Greater Stroke Severity Predominates Over All Other Factors For The Worse Outcome Of Cardioembolic Stroke

Background: Cardioembolic (CE) strokes are more disabling and more fatal than non-CE strokes. Multiple prognostic factors have been recognized, but the magnitude of their relative contribution has not been well explored.

Methods: Using a stroke outcome registry, we compared the outcomes of CE and non-CE strokes. The relative contribution of prognostic factors was assessed with multivariable models and model fitness improvement using -2 log-likelihood and Nagelkerke’s R 2 .

Results: A total of 1233 patients were included in this analysis. As compared to non-CE strokes, CE strokes had less mRS 0-2 outcomes (47.2% vs 68.5%, p<0.001), less mRS 0-1 outcomes (33.7% vs 53.5%, p<0.001), more mRS 5-6 outcomes (32.1% vs 10.9%, p<0.001), and higher mortality (19.2% vs 5.2%, p<0.001). When adjusting either baseline demographics or poststroke complications, the outcome differences remained significant. However, adjusting initial NIHSS score alone abolished the differences in mRS 0-2 outcome (Figure) and mRS 0-1 and mRS 5-6 outcomes. For mRS 0-2 outcome, the differences in -2 log-likelihood and Nagelkerke’s R 2 between univariable model and multivariable model were greater with adjusting NIHSS alone (-2 log-likelihood difference, 418; Nagelkerke’s R 2 difference, 38.7%) than with adjusting baseline demographics (184; 17.7%) or poststroke complication (279; 27.3%). Further adjustment of baseline demographics and poststroke complication to the initial NIHSS score adjustment resulted in a small shift of odds ratio. The decrement of -2 log-likelihood and the Nagelkerke’s R 2 of the model adjusting initial NIHSS score alone approached 70.2% and 76.7% of the model adjusting baseline demographics, poststroke complication, and initial NIHSS score.

Conclusion: Greater stroke severity predominates over all other factors for the worse outcome of CE stroke.

Abstract TP194: Internet-based Control Recruitment for a Case-Control Study of Major Risk Factors for Stroke in Korea: A Failure and Lessons Learned from the Experience

This study aimed to estimate the population attributable risks (PARs) of major risk factors for stroke in Korea through an internet-based case-control study and test the feasibility and validity of this approach.

Control subjects were recruited by a web-based questionnaire from April 2008 to September 2009. Cases were consecutive stroke patients hospitalized to during the same period. Each control was matched with 2 cases for age and sex. The presence of hypertension, diabetes, hypercholesterolemia, smoking, atrial fibrillation, coronary heart disease, history of stroke, family history of stroke and obesity were investigated. Age-standardized prevalence, adjusted odd ratios (ORs) and PARs for 9 risk factors for stroke were calculated.

One thousand forty one control subjects were matched with 2,082 cases. Adjusted ORs for stroke were 2.80 for hypertension, 3.56 for diabetes, 3.65 for smoking, 3.95 for history of stroke, and 1.25 for obesity. Risk of atrial fibrillation, coronary heart disease, and family history of stroke were not significant, while hypercholesterolemia showed inverse correlation. PARs for stroke were 16.3% for hypertension, 9.4% for diabetes, 23.6% for smoking, 5.84% for stroke history, and 4.18% for obesity. Comparisons of education level and religion between the control group and the national census data for validating its representativeness revealed significant discrepancy.

In conclusion, internet-based control recruitment for a case-control study of stroke risk factors may be feasible; however, careful approaches for reducing selection and reporting biases are essential.

Abstract WP63: Safety and Efficacy of Modest Blood Pressure Reduction with Valsartan in Acute Ischemic Stroke

Background and purpose Recently, the lowering of blood pressure (BP) with angiotensin-receptor blocker did not show the beneficial effect in patients with acute stroke. However, the management of BP in acute ischemic stroke has still been a matter of debate in clinical practice. We designed a prospective, randomized, open-labeled, blinded endpoints, multi-center study to evaluate Valsartan Efficacy oN modesT blood pressUre REduction in Acute Ischemic Stroke (VENTURE).

Methods Eligible patients were randomly assigned to receive valsartan or no anti-hypertensive agents as a control for 7 days after symptom onset by the central computerized system. Inclusion criteria were 1) age older than 18 years, 2) admission within 24 hours from onset, 3) treatment initiation within 48 hours, 4) NIH stroke scales 2-21, and 5) Systolic BP 150-185 mmHg. Primary endpoint was death or dependency measured as modified Rankin Scale score ≥ 3 at 90 days. Safety endpoints were early neurological deterioration within 7 days and mortality at 90 days. Thirty centers have participated since October 2008 in South Korea. Analyses were based on intention to treat. This study is registered as number NCT00874601 in ClinicalTrials.gov.

Results 405 patients were randomly assigned to valsartan (n=203) or control group (n=202), and primary endpoints were available for 373 patients (187 valsartan, 186 control). The BP reduction was significantly greater in valsartan group than in control group during the 7-day treatment (mean diastolic BP was 84.7±2.5 mmHg in valsartan group and 87.1±2.67 mmHg in control group; P=0.022). However, there was no difference in the primary endpoint between valsartan (n=46, 24.6%) and control (n=42, 22.6 %) groups (Odds ratio 1.13, 95% CI 0.79-1.63; p=0.643). In addition, safety endpoints including early neurological deterioration within 7 days (20 (10.7%) in valsartan and 11 (5.9%) in control group, p=0.137) and mortality at 90 days (2 in valsartan and 0 in control group, p=0.333) were similar between the two groups.

Conclusion The modest BP reduction with valsartan did not suggest any beneficial effect in patients with acute stroke and raised blood pressure. However, These findings might be because this study was underpowered owing to early termination.

Weekend admission in patients with acute ischemic stroke is not associated with poor functional outcome than weekday admission

Background and Purpose

Stroke requires consistent care, but there is concern over the "weekend effect", whereby a weekend admission results in a poor outcome. Our aim was to determine the impact of weekend admission on clinical outcomes in patients with acute ischemic stroke in Korea.

Methods

The outcomes of patients admitted on weekdays and weekends were compared by analyzing data from a prospective outcome registry enrolling 1247 consecutive patients with acute ischemic stroke admitted to four neurology training hospitals in South Korea between September 2004 and August 2005. The primary outcome was a poor functional outcome at 3 months, defined as modified Rankin Scale (mRS) of 3-6. Secondary outcomes were 3-month mortality, use of thrombolysis, complication rate, and length of hospitalization. Shift analysis was also performed to compare overall mRS distributions.

Results

On weekends, 334 (26.8%) patients were admitted. Baseline characteristics were comparable between the weekday and weekend groups except for more history of heart disease and shorter admission time in weekend group. Univariate analysis revealed poor functional outcome at 3 months, 3-month mortality, complication rate, and length of hospitalization did not differ between the two groups. In addition, overall mRS distributions were comparable (p=0.865). After adjusting for baseline factors and stroke severity, weekend admission was not associated with poor functional outcome at 3 months (adjusted odds ratio, 1.05; 95% CI, 0.74-1.50). Furthermore, none of secondary endpoints differed between the two groups in multivariate analysis.

Conclusions

Weekend admission was not associated with poor functional outcome than weekday admission in patients with acute ischemic stroke in this study. The putative weekend effect should be explored further by considering a wider range of hospital settings and hemorrhagic stroke.

Burden of ischemic stroke in Korea: analysis of disability-adjusted life years lost

Background and Purpose

Disability-adjusted life years (DALY), incorporating both disability and mortality, has been widely employed to measure regional and global burdens of stroke. Thus far, the DALY lost to stroke in a population has been estimated using only the crude population-level data; no previous study has incorporated refined data from stroke registries. The aim of this study was to integrate the stroke registry data and the population-level incidence data to project the nationwide DALY lost to ischemic stroke.

Methods

From the data of two large ischemic stroke registries, we derived an average DALY lost due to ischemic stroke for each of the following age groups: <45, 45-54, 55-64, 65-74, 75-84, and ≥85 years. The nationwide ischemic stroke incidence for each age group was extracted from a cardiovascular and cerebrovascular surveillance study that analyzed the 2004 Korean Health Insurance database.

Results

The average DALY lost due to ischemic stroke for the age groups <45, 45-54, 55-64, 65-74, 75-84, and ≥85 years was 5.07, 4.63, 4.35, 3.88, 2.88, and 1.73, respectively. By multiplying the incidence and the average DALY lost, the nationwide DALY lost was determined to be 9,952 for those <45 years, 24,608 for 45-54 years, 50,682 for 55-64 years, 88,875 for 65-74 years, 52,089 for 75-84 years, and 8,192 for ≥85 years, respectively. The projected nationwide DALY lost due to 64,688 ischemic strokes in 2004 was 234,399 (121,482 for men and 113,244 for women), and the DALY lost per 100,000 person-years was 483 (500 for men and 469 for women).

Conclusions

Incidence data from a population study and DALY values derived from stroke registries can be integrated to provide a more refined projection of the nationwide burden of ischemic stroke. In Korea, more than 230,000 years of healthy life are being lost annually due to ischemic stroke, and hence prompt action is imperative.

Stroke awareness decreases prehospital delay after acute ischemic stroke in Korea

BACKGROUND

Delayed arrival at hospital is one of the major obstacles in enhancing the rate of thrombolysis therapy in patients with acute ischemic stroke. Our study aimed to investigate factors associated with prehospital delay after acute ischemic stroke in Korea.

METHODS

A prospective, multicenter study was conducted at 14 tertiary hospitals in Korea from March 2009 to July 2009. We interviewed 500 consecutive patients with acute ischemic stroke who arrived within 48 hours. Univariate and multivariate analyses were performed to evaluate factors influencing prehospital delay.

RESULTS

Among the 500 patients (median 67 years, 62% men), the median time interval from symptom onset to arrival was 474 minutes (interquartile range, 170-1313). Early arrival within 3 hours of symptom onset was significantly associated with the following factors: high National Institutes of Health Stroke Scale (NIHSS) score, previous stroke, atrial fibrillation, use of ambulance, knowledge about thrombolysis and awareness of the patient/bystander that the initial symptom was a stroke. Multivariable logistic regression analysis indicated that awareness of the patient/bystander that the initial symptom was a stroke (OR 4.438, 95% CI 2.669-7.381), knowledge about thrombolysis (OR 2.002, 95% CI 1.104-3.633) and use of ambulance (OR 1.961, 95% CI 1.176-3.270) were significantly associated with early arrival.

CONCLUSIONS

In Korea, stroke awareness not only on the part of patients, but also of bystanders, had a great impact on early arrival at hospital. To increase the rate of thrombolysis therapy and the incidence of favorable outcomes, extensive general public education including how to recognize stroke symptoms would be important.

Gender differences in the mortality and outcome of stroke patients in Korea

BACKGROUND

We aimed to determine gender differences in outcomes and mortality in Korean stroke patients.

METHODS

We analyzed the demographics, risk factors, in-hospital mortality, functional outcomes at discharge, and any-cause mortality over a 5-year period for 18,364 Korean patients, and determined a cumulative mortality rate using Kaplan-Meier and Cox proportional hazards regression analyses to elucidate gender differences in stroke outcomes.

RESULTS

Women suffered strokes that were severer than those suffered by men. Although women had a lower risk of any-cause death than men, they exhibited poorer functional status at discharge.

CONCLUSION

In Korea, women lived longer, but had greater disabilities after strokes than men, indicating the need to develop gender-specific interventions to improve stroke outcomes and reduce the disability burden in women.

Diabetes mellitus and drug-induced Parkinsonism: a case-control study

To investigate if diabetes is more common in drug-induced parkinsonism patients. We performed a hospital-based retrospective case-control study on 44 drug-induced parkinsonism (DIP) patients, 177 Parkinson disease patients, and 176 acute stroke patients matched for age and sex who were seen over the same period at the same hospital. The frequency of diabetes, age-at onset and sex were compared between DIP and IPD or acute stroke. Multivariate analysis showed that patients with diabetes are more frequent in DIP compared with IPD (p<0.001, adjusted OR 5.48; 95% CI, 2.52-11.94). The frequency of diabetes in DIP was comparable to that in acute stroke patients (p=0.16, adjusted OR 0.62; 95% CI, 0.32-1.21). These data suggest that diabetes may be a risk factor for DIP. Drugs with dopamine receptor blocking potency should be avoided in elderly with diabetes.

Long-term outcomes of acute ischemic stroke in patients aged 80 years and older

PURPOSE

Short life expectancy influences decision-making when treating very old patients with acute ischemic stroke (AIS). We investigated mortality and survival duration in very old AIS patients (>or= 80 years) who received hospital care.

PATIENTS AND METHODS

Mortality data were obtained from medical records, structured telephone inquiries, death certificates from the Korean National Statistical Office, and social security data 5+/-1.9 years after stroke onset. Age, gender, vascular risk factors, and functional outcomes from modified Rankin scales (MRS) at discharge were analyzed as predictors of mortality.

RESULTS

Among 134 patients, 92 (68.7%) died. On Kaplan-Meier analysis, duration of survival of patients aged 80-84 years was longer than those aged 85-89 or 90-94 (24+/-6.4, 8+/-7.3, 7+/-2.0 months, respectively, p=0.002). Duration of survival of patients discharged in a state of MRS 0-1 was longer than the remaining groups at 47+/-4.8 months (p<0.001). In Cox proportional hazard analysis, age and MRS at discharge were independent predictors of mortality.

CONCLUSION

Long-term outcomes of very old patients with AIS are not uniformly grave, therefore predictors of mortality and estimated duration of survival should be considered during decision-making for treatment.