Neural network-based clustering model of ischemic stroke patients with a maximally distinct distribution of 1-year vascular outcomes.

Clustering stroke patients with similar characteristics to predict subsequent vascular outcome events is critical. This study aimed to compare several clustering methods, particularly a deep neural network-based model, and identify the best clustering method with a maximally distinct 1-year outcome in patients with ischemic stroke. Prospective stroke registry data from a comprehensive stroke center from January 2011 to July 2018 were retrospectively analyzed. Patients with acute ischemic stroke within 7 days of onset were included. The primary outcomes were the composite of all strokes (either hemorrhagic or ischemic), myocardial infarction, and all-cause mortality within one year. Neural network-based clustering models (deep lifetime clustering) were compared with other clustering models (k-prototype and semi-supervised clustering, SSC) and a conventional risk score (Stroke Prognostic Instrument-II, SPI-II) to obtain a distinct distribution of 1-year vascular events. Ultimately, 7,650 patients were included, and the 1-year primary outcome event occurred in 13.1%. The DLC-Kuiper UB model had a significantly higher C-index (0.674), log-rank score (153.1), and Brier score (0.08) than the other cluster models (SSC and DLC-MMD) and the SPI-II score. There were significant differences in primary outcome events among the 3 clusters (41.7%, 13.4%, and 6.5% in clusters 0, 1, and 2, respectively) when the DLC-Kuiper UB model was used. A neural network-based clustering model, the DLC-Kuiper UB model, can improve the clustering of stroke patients with a maximally distinct distribution of 1-year vascular outcomes among each cluster. Further studies are warranted to validate this deep neural network-based clustering model in ischemic stroke.

Screening for Atrial Fibrillation Using a Smartphone-Based Electrocardiogram in Korean Elderly.

Atrial fibrillation (AF) is responsible for 10-20% of cerebral infarctions. Several mobile devices have been developed to screen for AF and studies of AF screening have been conducted in several countries to evaluate the applicability of these mobile devices. In this tradition, we conducted a community-based AF screening using an automated single-lead electrocardiogram (SL-ECG). This survey examined 2,422 participants in a community dementia screening program who were aged 60 years or older in the preliminary study, and 5,366 participants at 9 Senior Welfare Centers aged 60 years or older in the expanded study. AF screening was conducted using an automated SL-ECG (Kardia Mobile, AliveCor, Mountain View, CA, USA). AF was confirmed with a 12-lead electrocardiogram in subjects classified as having AF on the SL-ECG. In the preliminary study, of the 2,422 subjects, 124 had AF on the SL-ECG. The prevalence of AF was 3.0% (95% confidence interval [CI]: 2.4-3.8). The positive predictive value (PPV) of SL-ECG was 58.9% (95% CI: 50.1-67.1). Of the subjects diagnosed with AF, 65.8% (95% CI: 54.3-75.6) were newly diagnosed. In an expanded study, of the 5,366 subjects, 289 had AF on SL-ECG. The prevalence was 2.6% (95% CI: 2.2-3.1) and PPV of SL-ECG was 48.8% (95% CI: 43.1-54.5). In this community-based AF screening, we found that AF is underdiagnosed and undertreated. These results suggest that the early detection of AF using mobile devices is needed in Korea.

Association of Coffee and Tea with Ferritin: Data from the Korean National Health and Nutrition Examination Survey (IV and V).

There have been few studies that have evaluated the association between coffee intake and iron in Korean population. Data from the Korean National Health and Nutrition Examination Survey (IV and V; 2007-2012) was used to investigate the association between coffee and green tea intake and serum ferritin levels in Korean adults. Beverage intake was assessed using a food frequency questionnaire. Multivariate linear regression was performed to evaluate the relationship between coffee and tea intake and serum ferritin levels, after adjusting for age, body mass index, education level, smoking status, alcohol consumption, physical activity, hypertension, diabetes mellitus, and daily iron intake. Coffee intake was negatively related to serum ferritin levels in both sexes. The multivariate-adjusted geometric mean of serum ferritin level was 100.7 ng/mL (95% confidence interval [CI]: 98.2-103.4) in men drinking <1 coffee/day, and 92.2 ng/mL (95% CI: 89.7-94.8) in those drinking ≥3 coffees/day. In women, the equivalent serum ferritin levels were 35.6 ng/mL (95% CI: 34.8-36.4) and 28.9 ng/mL (95% CI: 27.8-30.1). However, green tea intake was not related to serum ferritin levels. In conclusion, coffee consumption was associated with lower serum ferritin levels in Korean adults.

Association between Smoking and Unintentional Injuries among Korean Adults.

Using a cross-sectional representative national survey, we evaluated the relationship between cigarette smoking and unintentional injuries among Korean adults. We used data from the 2009 Korean Community Health Survey. Smoking status was defined as never smokers, ex-smokers, and current smokers. Current smokers were categorized into light daily smokers (1-10 cigarettes/day), moderate daily smokers (11-20 cigarettes/day), or heavy daily smokers (≥21 cigarettes/day). We used the Poisson regression model with a robust variance estimation to estimate prevalence rate ratios (PRR) and corresponding 95% confidence interval (95% CI). After adjusting for demographic characteristics, socioeconomic variables, lifestyle variables, and health status variables, former smokers (PRR, 1.19, 95% CI 1.11-1.28), light daily smokers (PRR 1.22, 95% CI 1.13-1.32), moderate daily smokers (PRR 1.33, 95% CI 1.24-1.42), and heavy daily smokers (PRR 1.40, 95% CI 1.25-1.57) had an increased risk for unintentional injuries compared with non-smokers. In conclusion, cigarette smoking is associated with unintentional injuries in a dose-response manner in Korean adults. The findings suggest that community smoking cessation programs may reduce morbidity and mortality from unintentional injuries.

Evaluation of dietary methionine requirement of male Korean native ducks for 3 weeks post-hatching.

A total of 336 1-day-old male Korean native ducks (KND) were used in a completely randomized design with seven dietary methionine levels (0.30-0.90% with 0.1% increment) to determine the methionine requirement of male Korean native ducks for 3 weeks after hatching. Each dietary treatment had six replicates with eight ducklings per pen. One duckling from each pen (n = 6) was sacrificed to weigh empty body and drumsticks at the end of the experiment. Final body weight and weight gain of 3 weeks old KND were increased with increasing dietary methionine levels up to 0.4%, and then decreased (P < 0.05) with a further increasing dietary methionine level. In contrast, feed conversion ratio of the KND decreased up to 0.4% and increased (P < 0.05) with the increasing dietary methionine level. Both empty body weight and proportions of empty body weight were linearly increased (P < 0.05) while the dietary methionine level elevated up to 0.4%. Estimated dietary methionine requirement for maximum body weights, daily gain and minimum feed conversion ratio were 0.36, 0.39 and 0.40%, respectively, when it was fitted into linear- and quadratic-plateau models.

Reconstruction of Postburn Contracture of the Forefoot Using the Anterolateral Thigh Flap.

BACKGROUND: Severe forefoot deformities, particularly those involving the dorsum of the foot, cause inconvenience in daily activities of living including moderate pain on the dorsal aspect of the contracted foot while walking and difficulty in wearing nonsupportive shoes due to toe contractures. This paper presents clinical results of reconstruction of severe forefoot deformity using the anterolateral thigh (ALT) free flap. METHODS: Severe forefoot deformities were reconstructed using ALT flaps in 7 patients (8 cases) between March 2012 and December 2015. The mean contracture duration was 28.6 years. RESULTS: All the flaps survived completely. The size of the flaps ranged from 8 cm × 5 cm to 19 cm × 8 cm. The mean follow-up period was 10 months (range, 7 to 15 months). There was no specific complication at both the recipient and donor sites. There was one case where the toe contracture could not be completely treated after surgery. All of the patients were able to wear shoes and walk without pain. Also, the patients were highly satisfied with cosmetic results. CONCLUSIONS: The ALT flap may be considered ideal for the treatment of severe forefoot deformity.

Erratum: correction of prevalence of falls by sex in article 'risk factors for falls in older korean adults: the 2011 community health survey'.

[This corrects the article on p. 1482 in vol. 29, PMID: 25408578.].

Risk factors for falls in older Korean adults: the 2011 Community Health Survey.

Falls are a major health problem for elderly populations worldwide. We analyzed data from the 2011 Korean Community Health Survey to identify potential risk factors for falls in a representative population-based sample of community-dwelling older Korean adults. Risk factors for falls were assessed by multivariate survey logistic regression models. The prevalence of falls was 16.9% in males and 24.3% in females [Corrected]. Age and female sex were associated with a higher risk of falls. Similarly, living alone, living in an urban area, poor self-rated health, and high stress were associated with a high risk of falls. Subjects with diabetes mellitus, stroke, osteoarthritis, osteoporosis, urinary incontinence, cataracts, or depression had a high risk of falls. However, subjects with hypertension were at low risk for falls. In conclusion, age, female sex, marital status, residence location, self-rated health, stress, and several chronic conditions were significantly associated with the risk for falls in the older Korean adults. Our findings suggest that these risk factors should be addressed in public health policies for preventing falls.

Gender Difference in the Level of HDL Cholesterol in Korean Adults.

BACKGROUND: High density lipoprotein (HDL) cholesterol level varies with ethnicity and gender. In Korea there has not been an agreement on standards for HDL cholesterol level. Therefore, in order to establish a foundation for research on HDL cholesterol, we investigated the gender difference in HDL cholesterol level after adjusting associated factors. METHODS: The study population included 4,465 individuals (1,833 men, 2,632 women) representing 33,502,918 Koreans 20 years of age or older, who participated in the 2005 Korean National Health and Nutrition Survey. After stratifying by gender, we analyzed the HDL cholesterol level according to the general characteristics of the study population. Then we identified independent factors associated with HDL cholesterol level. After adjusting for covariates, we estimated the gender difference in HDL cholesterol level. RESULTS: We demonstrated that age, current smoking, body mass index, alcohol intake, triglyceride and low density lipoprotein cholesterol level have significant impact on HDL cholesterol level. In addition, educational status was also an important factor for men, while fat intake was a significant factor for women. After adjusting associated factors, the means (standard errors) of HDL cholesterol level were 43.8 (0.2) mg/dL in men and 46.3 (0.2) mg/dL in women, respectively. CONCLUSION: The mean gender difference in HDL level (2.5 mg/dL) in Korean adults was, therefore, less than those observed in previous western studies.