Clinical Characteristics and Risk Factors of First-Ever Stroke in Young Adults: A Multicenter, Prospective Cohort Study.

Stroke in young adults has catastrophic consequences and has increased in prevalence, contrary to the trends of most other diseases. This study aimed to determine the major characteristics and risk factors for stroke in younger adults compared with older adults. From the Korean Stroke Cohort for Functioning and Rehabilitation, 10,584 patients with first-ever stroke between August 2012 and March 2015 were enrolled retrospectively and divided into younger (age ≤ 45) and older groups (age > 45). The clinical characteristics and risk factors of stroke were compared between the younger and older groups. The younger group comprised 915 patients (8.6%). The proportion of hemorrhage strokes in the younger group (42.3%) was significantly higher than in the older group (20.0%) (p < 0.001). Obesity, current smoking, and heavy alcohol consumption were significantly more common risk factors in the younger group than in the older group for all stroke types, whereas hypertension, diabetes mellitus, hyperlipidemia, atrial fibrillation, and coronary heart disease were significantly more frequent in the older group (both p < 0.001). The major risk factors in the younger group may be lifestyle-related. Therefore, increasing awareness of lifestyle-related risk factors may be necessary to prevent stroke in young adults.

Post-stroke Hyperglycemia in Non-diabetic Ischemic Stroke is Related With Worse Functional Outcome: A Cohort Study.

OBJECTIVE: To investigate long-term and serial functional outcomes in ischemic stroke patients without diabetes with post-stroke hyperglycemia. METHODS: The Korean Stroke Cohort for Functioning and Rehabilitation (KOSCO) is a large, multi-center, prospective cohort study of stroke patients admitted to participating hospitals in nine areas of Korea. From KOSCO, ischemic stroke patients without diabetes were recruited and divided into two groups: patients without diabetes without (n=779) and with post-stroke hyperglycemia (n=223). Post-stroke hyperglycemia was defined as a glucose level >8 mmol/L. Functional assessments were performed 7 days and 3, 6, and 12 months after stroke onset. RESULTS: There were no significant differences in baseline characteristics between the groups, except in the age of onset and smoking. Analysis of the linear correlation between the initial National Institutes of Health Stroke Scale (NIHSS) score and glucose level showed no significant difference. Among our functional assessments, NIHSS, Fugl-Meyer Assessment (affected side), Functional Ambulatory Category, modified Rankin Scale, and Korean Mini-Mental State Examination (K-MMSE) showed statistically significant improvements in each group. All functional improvements except K-MMSE were significantly higher in patients without post-stroke hyperglycemia at 7 days and 3, 6, and 12 months. CONCLUSION: The glucose level of ischemic stroke patients without diabetes had no significant correlation with the initial NIHSS score. The long-term effects of stress hyperglycemia showed worse functional outcomes in ischemic stroke patients without diabetes with post-stroke hyperglycemia.

Health Indicators Related to Disease, Death, and Reproduction.

One of the primary goals of epidemiology is to quantify various aspects of a population's health, illness, and death status and the determinants (or risk factors) thereof by calculating health indicators that measure the magnitudes of various conditions. There has been some confusion regarding health indicators, with discrepancies in usage among organizations such as the World Health Organization the, Centers for Disease Control and Prevention (CDC), and the CDC of other countries, and the usage of the relevant terminology may vary across papers. Therefore, in this review, we would like to propose appropriate terminological definitions for health indicators based on the most commonly used meanings and/or the terms used by official agencies, in order to bring clarity to this area of confusion. We have used appropriate examples to make each health indicator easy for the reader to understand. We have included practical exercises for some health indicators to help readers understand the underlying concepts.

Public Perception of the Concentration of Cardiac and Cerebrovascular Surgery to Metropolitan Hospitals.

BACKGROUND: This study investigates the perception of the general public regarding the concentration to metropolitan, hospitals of cardiac and cerebrovascular surgeries, and the perceived public need for government policies to resolve this issue. METHODS: A total of 800 participants were recruited for our telephone interview survey. Quota sampling was performed, adjusting for age and sex, to select by various geographic regions. Sampling with random digit dialing was performed; we called the randomly generated telephone numbers and made three attempts for non-responders before moving on to a different telephone number. RESULTS: Our sample population was 818 participants, 401 men (49.0%) and 417 women (51.0%). Our data showed that 85.5% of participants thought that cardiac surgery and neurosurgery patients are concentrated in large hospitals in Seoul. The principle reason for regional patients to want to receive surgery at major hospitals in Seoul was because of poor medical standards associated with regional hospitals (87.7%). We found that a vast majority of participants (97.5%) felt that government policies are needed to even out the clustering of cardiac surgery and neurosurgery patients, and that this clustering may be alleviated if policies that can specifically enhance the quality and the capacity of regional hospitals to carry out surgeries are adopted (98.3%). CONCLUSION: Government policy making must reflect public desiderata, and we suggest that these public health needs may be partially resolved through government-designated cardiac and neurosurgery specialist hospitals in regional areas.

Gender-Specific Factors Associated with Suicide Attempts among the Community-Dwelling General Population with Suicidal Ideation: the 2013 Korean Community Health Survey.

We identified traditional risk factors and investigated poorly understood risk factors for suicide attempts according to gender in a large Korean population. We analyzed the data from 6,768 males and 12,475 females with suicidal ideation obtained from the nationwide 2013 Korean Community Health Survey. The dependent variable was suicide attempts within the past year. There was a significant trend towards an increase in suicide attempts with decreasing age in both genders. Compared with those who were married, suicide attempts were significantly higher among those who were widowed, divorced, or separated for males (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.34-3.20), but lower for females (OR, 0.66; 95% CI, 0.45-0.98). Current smoking and depression were significant risk factor for suicide attempts in males and females. However, monthly household income, myocardial infarction, and osteoporosis were significantly associated with suicide attempts only in males, whereas education level, recipient of National Basic Livelihood Security, family contact, leisure activity, and drinking frequency were significantly associated only in females. These findings indicate that gender difference should be considered in the assessment, prevention, and management of future suicide attempts by community policy-makers and clinicians.

Public Awareness of Stroke and Its Predicting Factors in Korea: a National Public Telephone Survey, 2012 and 2014.

The aim of this study was to investigate time trends in the public awareness of stroke and its predicting factors. The target population was 9,600 community-dwelling adults, aged 19-79 years, in 16 metropolitan cities and provinces in Korea. The survey samples in 2012 and 2014 were selected separately (entirely different sets of subjects) using a proportionate quota sampling method. Information concerning knowledge of stroke and demographics was collected by trained telephone interviewers using random digit dialing. After excluding subjects with a non-response or refusal to answer any question, the analyses included 8,191 subjects in 2012 and 8,127 subjects in 2014. Respondents' awareness of stroke warning signs (numbness or weakness, difficulty speaking or understanding speech, dizziness, visual impairment, and severe headache) was highest for difficulty speaking or understanding speech (80.9% in 2012 and 86.4% in 2014). There were significant increases in the proportion of respondents understanding the appropriate action (i.e., calling an ambulance) at the time of stroke occurrence (59.6% to 67.1%), and in the proportion aware of the general need for prompt treatment (86.7% to 89.8%). In multivariable logistic regression analysis, older age, higher education level, higher household income, current non-smoking, exposure to stroke-related public relations materials, and experience of stroke education were significantly associated with both high knowledge of stroke warning signs and awareness of the need for prompt treatment. Between 2012 and 2014, the public's awareness of stroke increased significantly. More specialized interventions, including public relations materials and education, should focus on subgroups who have lower stroke knowledge.

Representative levels of blood lead, mercury, and urinary cadmium in youth: Korean Environmental Health Survey in Children and Adolescents (KorEHS-C), 2012-2014.

BACKGROUND: This study examined levels of blood lead and mercury, and urinary cadmium, and associated sociodemographic factors in 3-18 year-old Korean children and adolescents. MATERIALS AND METHODS: We used the nationally representative Korean Environmental Health Survey in Children and Adolescents data for 2012-2014 and identified 2388 children and adolescents aged 3-18 years. The median and 95th percentile exposure biomarker levels with 95% confidence intervals (CIs) were calculated. Multivariate regression analyses were performed on log transformed exposure biomarker levels adjusted for age, sex, area, household income, and father's education level. The median exposure biomarker levels were compared with data from Germany, the US, and Canada, as well as the levels of Korean children measured at different times. RESULTS: The median levels of blood lead and mercury, as well as urinary cadmium were 1.23µg/dL, 1.80µg/L, and 0.40µg/L (95% CIs, 1.21-1.25, 1.77-1.83, and 0.39-0.41, respectively). The blood lead levels were significantly higher in boys and younger children (p<0.0001) and children with less educated fathers (p=0.004) after adjusting for covariates. Urinary cadmium level increased with age (p<0.0001). The median levels of blood mercury and urinary cadmium were much higher in Korean children and adolescents than those in their peers in Germany, the US, and Canada. Blood lead levels tended to decrease with increasing age and divergence between the sexes, particularly in the early teen years. Median levels of blood lead and urinary cadmium decreased since 2010. CONCLUSION: Sociodemographic factors, including age, sex, and father's education level were associated with environmental exposure to heavy metals in Korean children and adolescents. These biomonitoring data are valuable for ongoing surveillance of environmental exposure in this vulnerable population.

Chronic Kidney Disease and Functional Outcomes 6 Months after Ischemic Stroke: A Prospective Multicenter Study.

BACKGROUND: The aim of this study was to investigate whether chronic kidney disease (CKD) predicts the outcome of the Functional Independence Measure (FIM) and the Korean version of the modified Barthel Index (K-MBI) 6 months after stroke with adjustment for age, gender, education, smoking, drinking, obesity, hypertension, diabetes mellitus, dyslipidemia, the FIM or K-MBI at discharge and the National Institutes of Health Stroke Scale (NIHSS) score 7 days post stroke. METHODS: This study is an interim report of the Korean Stroke Cohort for Functioning and Rehabilitation. The sample included 2,037 ischemic stroke patients aged 18 years or older. The FIM and K-MBI scores were assessed at discharge and at 6 months after the onset of stroke. The estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. CKD was defined as an eGFR <60 ml/min/1.73 m2. RESULTS: Overall, the mean age was 65.5 (±12.4) years. The proportion of men was 62.6%. The proportion of CKD cases was 12.7%. The means of the 6-month FIM and K-MBI were 109.8 (±27.9) and 87.0 (±26.4), respectively. In multiple linear regressions, the 6-month FIM after stroke was significantly associated with CKD (-2.85, p < 0.05), age (-0.29, p < 0.01), the FIM at discharge (0.46, p < 0.01) and the 7-day NIHSS score (-1.71, p < 0.01). Additionally, the post-stroke 6-month K-MBI was significantly associated with CKD (-2.88, p < 0.01), age (-0.27, p < 0.01), the K-MBI at discharge (0.46, p < 0.01) and the 7-day NIHSS score (-1.55, p < 0.01). CONCLUSIONS: This nationwide hospital-based cohort study showed that CKD might predict poor 6-month FIM and K-MBI scores in ischemic stroke patients.

Seropositivity among Korean Young Adults Approximately 2 Years after a Single-Dose Vaccination against Hepatitis A Virus.

We previously observed 80.7% seropositivity and a significant interaction between gender and hepatitis A virus (HAV) vaccine type (Havrix vs. Epaxal) on the seropositivity approximately 11 months after single-dose HAV vaccinations in Korean young adults. Our objective was to evaluate seropositivity approximately 2 years after a single-dose HAV vaccination and the influence of demographic characteristics on seropositivity, including the interaction between gender and vaccine type. Seronegative medical school students were randomly vaccinated with Havrix or Epaxal. Based on a total serum anti-HAV antibody titer cutoff of 20 IU/mL, 338 participants (76.0%) of the 445 vaccinees were seropositive 20-25 months after a single-dose HAV vaccination. The seropositive rates were similar after vaccination with Havrix (77.0%) and Epaxal (74.9%). Univariate analysis indicated that female (p = 0.052) and less obese (p < 0.001) participants had a higher seropositive rate, whereas other characteristics such as age, alcohol use, smoking history, vaccine type, and follow-up duration were not associated with seropositivity. Multivariate analysis indicated that women (p = 0.026) and participants with moderate alcohol use (p < 0.001) showed significantly higher seropositive rates than men and participants with no or low alcohol use, respectively. The seropositive rates after vaccination with Havrix and Epaxal were 70.9% and 67.5% in men and 87.7% and 91.3% in women, respectively (p for interaction = 0.304). Compared with the seropositive rate approximately 11 months after vaccination, the seropositive rate decreased substantially only in men in the Havrix group (11.0% points), and consequently, the interaction between gender and vaccine type disappeared while seropositivity remained high (87.7% and 91.3% in Havrix and Epaxal groups, respectively) among women approximately 2 years after vaccination. Further studies are needed to assess whether the seropositive rate would be maintained in all groups more than 2 years after a single-dose HAV vaccination.

Normative and mean carotid intima-media thickness values according to metabolic syndrome in Koreans: the Namwon study.

OBJECTIVES: We determined the gender- and age-specific normative values of carotid intima-media thickness (IMT) in a healthy Korean population. We also present the mean age-specific carotid IMT values according to the presence of metabolic syndrome (MetS) and the number of MetS components. METHODS: A total of 9374 subjects from the Namwon Study aged 45-74 years were included in the analysis. Subjects without hypertension, diabetes, dyslipidemia, obesity, and current smoking were classified as the healthy reference population (n = 2595). MetS was identified by the presence of three or more of the following five components: abdominal obesity, high triglycerides, low high-density lipoprotein cholesterol, high blood pressure, and high fasting blood glucose. Common carotid artery IMT (CCA-IMT) and carotid bulb IMT values were determined in a region free of plaque by B-mode carotid ultrasonography. RESULTS: The mean normative CCA-IMT values of 45-49, 50-54, 55-59, 60-64, 65-69, and 70-74 year old males were 0.614, 0.671, 0.711, 0.759, 0.783, and 0.787 mm and 0.613, 0.653, 0.689, 0.718, 0.753, and 0.778 mm for females, respectively. An increase in CCA-IMT of 0.007 mm/year was estimated in both genders. The mean CCA-IMT values of subjects with 0, 1, 2, 3, 4, and 5 MetS components were 0.744, 0.753, 0.765, 0.766, 0.771, and 0.798 mm for males and 0.688, 0.705, 0.724, 0.734, 0.757, and 0.762 mm for females, respectively. CONCLUSION: The gender-specific normative carotid IMT values were determined in a large healthy Korean population. An increasing trend in the CCA-IMT values was observed with an increasing number of MetS components in both genders.

The immunogenicity of a single dose of hepatitis A virus vaccines (Havrix® and Epaxal®) in Korean young adults.

PURPOSE: Assessing the immunogenicity of a single dose of hepatitis A virus (HAV) vaccines is important because some people receive only a single dose. However, previous studies have shown variable results and have not examined the effects of demographic characteristics other than gender. This study was performed to examine the immunogenicity of a single dose of HAV vaccine according to the vaccine type and demographic characteristics in young adults. MATERIALS AND METHODS: Seronegative medical school students were randomly allocated to receive either Havrix or Epaxal. RESULTS: After approximately 11 months, the seroconversion rate in 451 participants was 80.7%. In men, the Havrix group showed a significantly higher seroconversion rate (81.9%) than the Epaxal group (69.2%), whereas both vaccine groups showed similarly high immunogenicity in women (Havrix: 90.1%, Epaxal: 92.9%; P for interaction=0.062). According to the results of a multivariate analysis, Epaxal showed significantly lower immunogenicity than Havrix only in men. Age, obesity, drinking, smoking, and follow-up time did not significantly affect seroconversion in either gender. CONCLUSION: The seroconversion rate of single-dose HAV vaccines was low in men, particularly in those who received Epaxal. Our results suggest that gender effects should be considered when comparing the immunogenicity of different HAV vaccines.

Identification of single nucleotide polymorphisms in the TNFRSF17 gene and their association with gastrointestinal disorders.

TNFRSF17 is preferentially expressed in mature B lymphocytes, and may be important for the development of B cells. TNFRSF17 is selected as a candidate susceptibility gene to IBD pathogenesis by our cDNA microarray analysis, and we showed the specific expression of TNFRSF17 in resting and activated CD19(+) cells obtained from human blood. We identified four SNPs (g-1729G>A, g.2295T>C, g.2445G>A and g.2493G>A) and one variation site (g.894delT) in the TNFRSF17 gene using direct sequencing analysis. In addition, the association of the genotype and allelic frequencies of these SNPs was studied in healthy controls and in patients with ulcerative colitis (UC) or irritable bowel syndrome (IBS). Although, the genotype and allelic frequencies of these SNPs, in the UC and IBS patients, were not significantly different from those in the healthy controls, the distribution of the AAG, GGA, AGG and AAA haplotypes, of the SNPs (g.-1729G>A, g.2445G> A and g.2493G>A) associated with the TNFRSF17 gene, in the UC patients, were notably different from those of the healthy controls (P = 0.002, 0.002, 4.7E-4 and 3.3E-6, respectively). Moreover, the frequencies of the AAG, AGG, GAG and GAA haplotypes were significantly different in the IBS patients compared to the healthy controls (P = 4.2E-5, 4.4E-17, 1.8E-22 and 1.6E-10, respectively). These results suggest that the haplotypes of the TNFRSF17 polymorphisms might be associated with UC and IBS susceptibility.

Association between glutathione S-transferase M1 and T1 polymorphisms and increased risk for bladder cancer in Korean smokers.

We evaluated the relationship between polymorphisms in the GSTM1 and GSTT1 genes and smoking status in a case-controlled study of a Korean population. The GSTM1 and GSTT1 genotypes were determined using a polymerase chain reaction (PCR)-based method and prognostic factors, such as staging and grading were evaluated for 126 bladder cancer patients, and 204 control subjects. Smoking represented a high-risk factor (odds ratio (OR)=4.8, 95% confidence interval (CI)=2.9-8.0) for the patients with bladder cancer. The frequency of GSTM1 null individuals was higher than in the controls, but the differences were not statistically significant (OR=1.56, 95% CI=2.9-8.0). For Korean subjects who smoked more than 1 pack of cigarettes per year (PPY), the increased risk of bladder cancer was associated with the GSTM1 null genotype (OR=0.5, 95% CI=0.3-0.9). Low-stage bladder tumors were more common among the GSTM1 null genotypes (OR=2.3; 95% CI=1.1-5.5). This study suggests that in Korean subjects the GSTM1 null genotype may be associated with increased risk for bladder cancer, in a manner that appears to depend upon smoking status. And also, in bladder cancer patients the GSTM1 null genotype appears to be associated with a poorer prognosis with low stage bladder tumors.

Prognostic potential of glutathione S-transferase M1 and T1 null genotypes for gastric cancer progression.

To improve understanding of glutathione S-transferase (GST) behavior in terms of a development and prognostic factor for gastric adenocarcinoma, we investigated the association between the GSTM1 and GSTT1 null genotypes and gastric cancer risk or the prognostic value of the GSTM1 and GSTT1 null genotypes was evaluated. Using a polymerase chain reaction-based method, the frequencies of GSTM1 and GSTT1 genotypes and prognostic factors, such as staging, differentiation, and histologic type (intestinal vs. diffuse), were evaluated in 80 patients with curatively resected primary gastric adenocarcinoma. The frequencies of GSTM1 and GSTT1 null individuals were higher in the gastric cancer group, but the differences were not statistically significant (for GSTM1 null odds ratio (OR)=0.86; 95% confidence interval (CI)=0.49-1.51 and for GSTT1, OR=0.97; 95% CI=0.55-1.71). Since the GSTM1 and GSTT1 null genotypes are potential indicators of gastric adenocarcinoma, we examined the relationship between the GSTM1 and GSTT1 genotypes and prognostic factors. In terms of the histologically diffuse type of cancer, GSTM1 indicated an approximately 3.24-fold increase (OR=3.24; 95% CI=1.05-10.17). With respect to gastric cancer differentiation, the frequency of the GSTM1 null genotype was linked with a statistically significant increase in risk (3.42-fold) for the high-grade type (OR=3.42; CI=1.02-13.24). Our results indicate that there is no obvious relationship between GSTM1 and GSTT1 polymorphisms and the development of gastric cancer. However, in Korean gastric adenocarcinoma patients the GSTM1 null genotype appears to be associated with a poorer prognosis.