BACKGROUND/AIMS: Race and ethnicity are important determinants when estimatingglomerular filtration rate (GFR). The Korean coefficients for the isotope dilution mass spectrometry (IDMS) Modification of Diet in Renal Disease (MDRD) Study equations were developed in 2010. However, the coefficients have not been validated. The aim of this study was to validate the performance of the Korean coefficients for the IDMS MDRD Study equations. METHODS: Equation development and validation were performed in separate groups (development group, n = 147 from 2008 to 2009; validation group, n = 125 from 2010 to 2012). We compared the performance of the original IDMS MDRD equations and modified equations with Korean coefficients. Performance was assessed by comparing correlation coefficients, bias, and accuracy between estimated GFR and measured GFR, with systemic inulin clearance using a single injection method. RESULTS: The Korean coefficients for the IDMS MDRD equations developed previously showed good performance in the validation group. The new Korean coefficients for the four- and six-variable IDMS MDRD equations using both the development and validation cohorts were 1.02046 and 0.97300, respectively. No significant difference was detected for the new Korean coefficients, in terms of estimating GFR, between the original and modified IDMS MDRD Study equations. CONCLUSIONS: The modified equations with Korean coefficients for the IDMS MDRD Study equations were not superior to the original equations for estimating GFR. Therefore, we recommend using the original IDMS MDRD Study equation without ethnic adjustment in the Korean population.
Adult ; Aged ; *Asian Continental Ancestry Group ; Biomarkers/blood ; Case-Control Studies ; Chromatography, High Pressure Liquid ; Creatinine/blood ; Female ; *Glomerular Filtration Rate ; Humans ; Indicator Dilution Techniques ; Inulin/administration & dosage/blood ; Kidney/*physiopathology ; Male ; Mass Spectrometry ; Middle Aged ; *Models, Biological ; Oligosaccharides/administration & dosage/blood ; Predictive Value of Tests ; Renal Insufficiency, Chronic/blood/*diagnosis/ethnology/physiopathology ; Reproducibility of Results ; Republic of Korea

PURPOSE: This study determined which obesity measurement correlates the best with diabetes and prediabetes. MATERIALS AND METHODS: This cross-sectional study enrolled 1603 subjects (611 men, 992 women; age 30-64 years) at the Cardiovascular and Metabolic Diseases Etiology Research Center. Body mass index, waist circumference, waist-height ratio, waist-hip ratio, waist-thigh ratio, and visceral fat were used as measures of obesity. Visceral fat was acquired using dual-energy X-ray absorptiometry (DXA). The prevalences of diabetes and prediabetes were defined using the criteria in the American Diabetes Association 2015 guidelines. RESULTS: After adjusting for age and other potential confounding factors, participants with a visceral fat mass in the upper 10th percentile had a higher odds ratio (OR) for diabetes and prediabetes than the upper 10th percentile of other adiposity indices [men, OR=15.9, 95% confidence interval (CI)=6.4-39.2; women, OR=6.9, 95% CI=3.5-13.7]. Visceral fat mass also had the highest area under the curve with diabetes and prediabetes in both men (0.69, 95% CI=0.64-0.73) and women (0.70, 95% CI=0.67-0.74) compared to other anthropometric measurements of obesity. CONCLUSION: Visceral fat mass measured using DXA is an indicator of diabetes or prediabetes, due to its ability to differentiate between abdominal visceral and subcutaneous fat.
Absorptiometry, Photon ; *Adiposity ; Adult ; Anthropometry ; Asian Continental Ancestry Group/*statistics & numerical data ; Biomarkers/blood ; Body Mass Index ; Cross-Sectional Studies ; Diabetes Mellitus/*ethnology ; Female ; Humans ; *Intra-Abdominal Fat ; Male ; Middle Aged ; Obesity/complications/*ethnology ; Odds Ratio ; Prediabetic State/*ethnology ; Prevalence ; Prospective Studies ; Republic of Korea/epidemiology ; Waist Circumference

PURPOSE: The genes for cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex subunit 1 (VKORC1) have been identified as important genetic determinants of warfarin dosing and have been studied. We developed warfarin algorithm for Korean patients with stroke and compared the accuracy of warfarin dose prediction algorithms based on the pharmacogenetics. MATERIALS AND METHODS: A total of 101 patients on stable maintenance dose of warfarin were enrolled. Warfarin dosing algorithm was developed using multiple linear regression analysis. The performance of all the algorithms was characterized with coefficient of determination, determined by linear regression, and the mean of percent deviation was used to predict doses from the actual dose. In addition, we compared the performance of the algorithms using percentage of predicted dose falling within ±20% of clinically observed doses and dividing the patients into a low-dose group (≤3 mg/day), an intermediate-dose group (3-7 mg/day), and high-dose group (≥7 mg/day). RESULTS: A new developed algorithms including the variables of age, body weight, and CYP2C9 and VKORC1 genotype. Our algorithm accounted for 51% of variation in the warfarin stable dose, and performed best in predicting dose within 20% of actual dose and intermediate-dose group. CONCLUSION: Our warfarin dosing algorithm may be useful for Korean patients with stroke. Further studies to elucidate clinical utility of genotype-guided dosing and find the additional genetic association are necessary.
Aged ; *Algorithms ; Anticoagulants/*administration & dosage/therapeutic use ; Cytochrome P-450 CYP2C9/*genetics ; Dose-Response Relationship, Drug ; Female ; Genotype ; Humans ; International Normalized Ratio ; Linear Models ; Male ; Middle Aged ; Multivariate Analysis ; Pharmacogenetics ; Regression Analysis ; Republic of Korea ; Stroke/*drug therapy/ethnology ; Vitamin K Epoxide Reductases/*genetics ; Warfarin/*administration & dosage/therapeutic use

PURPOSE: The association between the red cell distribution width (RDW) and vasospastic angina (VSA) has not been elucidated. We investigated the association of the RDW with the incidence and angiographic subtypes of VSA in Korean patients. MATERIALS AND METHODS: A total of 460 patients who underwent intracoronary ergonovine provocation tests were consecutively enrolled and classified into two groups: the VSA group (n=147, 32.0%) and non-VSA group (n=313, 68.0%). The subjects were classified into 3 subgroups (tertiles) according to the baseline level of RDW assessed before the angiographic provocation test. RESULTS: The VSA group had a higher RDW than the non-VSA group (12.9±0.8% vs. 12.5±0.7%, p=0.013). The high RDW level demonstrated an independent association with the high incidence of VSA [second tertile: hazard ratio (HR) 1.96 (1.13-2.83), third tertile: HR 2.33 (1.22-3.47), all p<0.001]. Moreover, the highest RDW tertile level had a significant association with the prevalence of the mixed-type coronary spasm [HR 1.29 (1.03-1.59), p=0.037]. CONCLUSION: The high level of RDW was significantly associated with the prevalence of VSA and the high-risk angiographic subtype of coronary spasm, suggesting that a proactive clinical investigation for VSA could be valuable in Korean patients with an elevated RDW.
Aged ; Aged, 80 and over ; Angina Pectoris/*blood/ethnology ; Coronary Angiography/methods ; Coronary Vasospasm/*blood/ethnology ; Erythrocyte Indices/*physiology ; Female ; Humans ; Incidence ; Male ; Middle Aged ; Prevalence ; Proportional Hazards Models ; Republic of Korea/epidemiology

We aimed to examine the potential relationship between season of birth (SOB) and clinical characteristics in Korean patients with unipolar non-psychotic major depressive disorder (MDD). Using data from the Clinical Research Center for Depression (CRESCEND) study in South Korea, 891 MDD patients were divided into two groups, those born in spring/summer (n=457) and those born in autumn/winter (n=434). Measurement tools comprising the Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, Brief Psychiatric Rating Scale, Scale for Suicidal Ideation, Clinical Global Impression of severity, Social and Occupation Functional Assessment Scale, WHO Quality of Life assessment instrument-abbreviated version, Alcohol Use Disorder Identification Test, and Temperament and Character Inventory were used to evaluate depression, anxiety, overall symptoms, suicidal ideation, global severity, social function, quality of life, drinking, and temperament and character, respectively. Using independent t-tests for continuous variables and χ2 tests for discrete variables, the clinical characteristics of the two groups were compared. MDD patients born in spring/summer were on average younger at onset of first depressive episode (t=2.084, p=0.038), had greater loss of concentration (χ2=4.589, p=0.032), and were more self-directed (t=2.256, p=0.025) than those born in autumn/winter. Clinically, there was a trend for the MDD patients born in spring/summer to display the contradictory characteristics of more severe clinical course and less illness burden; this may have been partly due to a paradoxical effect of the 5-HT system.
Adult ; Age of Onset ; Aged ; Alcohol Drinking ; Bipolar Disorder/*diagnosis/*ethnology/psychology ; Character ; Cost of Illness ; Depression ; Depressive Disorder, Major/*diagnosis/*ethnology/psychology ; Female ; Humans ; Male ; Middle Aged ; Personality Inventory/statistics & numerical data ; *Quality of Life ; Republic of Korea/epidemiology ; *Seasons ; Temperament

PURPOSE: Roflumilast is the only oral phosphodiesterase 4 inhibitor approved to treat chronic obstructive pulmonary disease (COPD) patients [post-bronchodilator forced expiratory volume in 1 second (FEV1) <50% predicted] with chronic bronchitis and a history of frequent exacerbations. This study evaluated the efficacy and safety of roflumilast in Korean patients with COPD and compared the efficacy based on the severity of airflow limitation. MATERIALS AND METHODS: A post-hoc subgroup analysis was performed in Korean COPD patients participating in JADE, a 12-week, double-blinded, placebo-controlled, parallel-group, phase III trial in Asia. The primary efficacy endpoint was the mean [least-squares mean adjusted for covariates (LSMean)] change in post-bronchodilator FEV1 from baseline to each post-randomization visit. Safety endpoints included adverse events (AEs) and changes in laboratory values, vital signs, and electrocardiograms. RESULTS: A total of 260 Korean COPD patients were recruited, of which 207 were randomized to roflumilast (n=102) or placebo (n=105) treatment. After 12 weeks, LSMean post-bronchodilator FEV1 increased by 43 mL for patients receiving roflumilast and decreased by 60 mL for those taking placebo. Adverse events were more common in the roflumilast group than in the placebo group; however, the types and frequency of AEs were comparable to those reported in previous studies. CONCLUSION: Roflumilast significantly improved lung function with a tolerable safety profile in Korean COPD patients irrespective of the severity of airflow limitation.
Aged ; Aminopyridines/*therapeutic use ; *Asian Continental Ancestry Group ; Benzamides/*therapeutic use ; Cyclopropanes/therapeutic use ; Double-Blind Method ; Female ; Humans ; Male ; Middle Aged ; Phosphodiesterase 4 Inhibitors/*therapeutic use ; Pulmonary Disease, Chronic Obstructive/*drug therapy/*ethnology/physiopathology ; Republic of Korea ; Respiratory Function Tests ; Treatment Outcome

PURPOSE: Up to 71% of South Korean postmenopausal women have vitamin D deficiency {serum 25-hydroxyvitamin D [25(OH) D] level <50 nmol/L}. Data on vitamin D supplementation was collected during the screening phase of an efficacy/safety study of denosumab in Korean postmenopausal women with osteoporosis. This report describes the effect of vitamin D supplementation on repletion to 25(OH)D levels ≥50 nmol/L in Korean postmenopausal women with osteoporosis. MATERIALS AND METHODS: Vitamin D levels of Korean postmenopausal women (60-90 years old) were measured by extracting 25(OH)D2 and 25(OH)D3 from serum samples via protein precipitation and using liquid chromatography with tandem mass spectrometry detection. Calibration curves were constructed from the mass chromatograms to obtain total vitamin D levels. Subjects with serum 25(OH)D levels <50 nmol/L were supplemented with 1000 IU of vitamin D tablets during the 2.5-month-long screening period. Dose, frequency, and duration were determined by the investigator. If repletion was achieved (≥50 nmol/L) on retest, subjects were eligible to be rescreened for study entry. RESULTS: Of 371 subjects screened, 191 (52%) required vitamin D supplementation, and 88% (168 of 191) were successfully repleted. More than half of the subjects (58%) who were successfully repleted received doses of 2000 IU daily. The mean time to successful repletion was 31 days (standard deviation 8.4 days; range 11-48 days). CONCLUSION: Supplementation with daily median doses of 2000 IU vitamin D successfully repleted 88% of Korean postmenopausal women with osteoporosis within 48 days to a serum vitamin D level of 50 nmol/L.
Aged ; Aged, 80 and over ; *Asian Continental Ancestry Group ; Bone Density Conservation Agents/*therapeutic use ; *Dietary Supplements ; Double-Blind Method ; Female ; Humans ; Middle Aged ; Osteoporosis, Postmenopausal/*complications/drug therapy/ethnology ; Postmenopause/blood ; Republic of Korea ; Vitamin D/analogs & derivatives/blood/*therapeutic use ; Vitamin D Deficiency/diagnosis/*drug therapy/ethnology

PURPOSE: The efficacy and safety of denosumab was compared with placebo in Korean postmenopausal women with osteoporosis in this phase III study. MATERIALS AND METHODS: Women aged 60 to 90 years with a T-score of <-2.5 and ≥-4.0 at the lumbar spine or total hip were randomized to a single 60 mg subcutaneous dose of denosumab or placebo for the 6-month double-blind phase. Eligible subjects entered the 6-month open-label extension phase and received a single dose of denosumab 60 mg. RESULTS: Baseline demographics were similar in the 62 denosumab- and 64 placebo-treated subjects who completed the double-blind phase. Treatment favored denosumab over placebo for the primary endpoint {mean percent change from baseline in lumbar spine bone mineral density (BMD) at Month 6 [3.2% (95% confidence interval 2.1%, 4.4%; p<0.0001)]}; and secondary endpoints (mean percent change from baseline in lumbar spine BMD at Month 1, total hip, femoral neck, and trochanter BMD at Months 1 and 6, and median percent change from baseline in bone turnover markers at Months 1, 3, and 6). Endpoint improvements were sustained over 12 months in the open-label extension (n=119). There were no new or unexpected safety signals. CONCLUSION: Denosumab was well tolerated and effective in increasing BMD and decreasing bone turnover markers over a 12-month period in Korean postmenopausal women. The findings of this study demonstrate that denosumab has beneficial effects on the measures of osteoporosis in Korean postmenopausal women.
Aged ; Aged, 80 and over ; *Asian Continental Ancestry Group ; Bone Density ; Bone Density Conservation Agents/*therapeutic use ; Denosumab/*therapeutic use ; Double-Blind Method ; Female ; Femur ; Femur Neck ; Humans ; Lumbar Vertebrae ; Middle Aged ; Osteoporosis, Postmenopausal/*drug therapy/*ethnology ; Postmenopause ; Republic of Korea

PURPOSE: This study was conducted to assess predictor variables of husbands in multicultural families and examine the relationship among variables after setting up a hypothetical model including influencing factors, so as to provide a framework necessary for developing nursing interventions of domestic violence. METHODS: The participants were 260 husbands in multicultural families in four cities in Korea. Data were analyzed using SPSS 22.0 and AMOS 20.0. RESULTS: Self-control, social support, family of origin violence experience and stress on cultural adaptation directly affected to dysfunctional communication, and the explanatory power of the variables was 64.7%. Family of origin violence experience in domestic stress on cultural adaptation, and dysfunctional communication were directly related to domestic violence in multicultural families, and the explanatory power of the variables was 64.6%. We found out that all variables in the model had mediation effects to domestic violence through dysfunctional communication. In other words, self-control and social support had complete mediation effects, and family of origin violence experience in domestic violence and stress on cultural adaptation had partial mediation effects. CONCLUSIONS: The variables explained in this study should be considered as predictive factors of domestic violence in multicultural families, and used to provide preventive nursing intervention. Our resutls can be taken into account for developing and implementing programs on alleviating dysfunctional communication in multicultural families in Korea.
Acculturation ; Communication ; Cross-Sectional Studies ; *Cultural Diversity ; Domestic Violence/ethnology/*statistics & numerical data ; Emigrants and Immigrants/psychology/statistics & numerical data ; Female ; Humans ; Male ; Models, Psychological ; Republic of Korea/epidemiology ; Self-Control/psychology ; Social Support ; Spouses/ethnology/psychology/statistics & numerical data ; Stress, Psychological/ethnology/etiology

PURPOSE: The aim of the present study was to develop an osteoporosis risk-assessment model to identify high-risk individuals among Korean men. MATERIALS AND METHODS: The study used data from 1340 and 1110 men > or =50 years who participated in the 2009 and 2010 Korean National Health and Nutrition Examination Survey, respectively, for development and validation of an osteoporosis risk-assessment model. Osteoporosis was defined as T score < or =-2.5 at either the femoral neck or lumbar spine. Performance of the candidate models and the Osteoporosis Self-assessment Tool for Asian (OSTA) was compared with sensitivity, specificity, and area under the receiver operating characteristics curve (AUC). A net reclassification improvement was further calculated to compare the developed Korean Osteoporosis Risk-Assessment Model for Men (KORAM-M) with OSTA. RESULTS: In the development dataset, the prevalence of osteoporosis was 8.1%. KORAM-M, consisting of age and body weight, had a sensitivity of 90.8%, a specificity of 42.4%, and an AUC of 0.666 with a cut-off score of -9. In the validation dataset, similar results were shown: sensitivity 87.9%, specificity 39.7%, and AUC 0.638. Additionally, risk categorization with KORAM-M showed improved reclassification over that of OSTA up to 22.8%. CONCLUSION: KORAM-M can be simply used as a pre-screening tool to identify candidates for dual energy X-ray absorptiometry tests.
Aged ; Asian Continental Ancestry Group/*statistics & numerical data ; Bone Density ; Female ; Humans ; Male ; Middle Aged ; *Models, Biological ; Nutrition Surveys ; Osteoporosis/*diagnosis/ethnology ; Predictive Value of Tests ; Prevalence ; ROC Curve ; Reproducibility of Results ; Republic of Korea/epidemiology ; Risk Assessment/*methods ; Sensitivity and Specificity ; Surveys and Questionnaires/*standards