Association between Obesity and Cardiovascular Disease Risk Factors in Different Age Groups of Adolescents: An Analysis of Data from the Korean National Health and Nutritional Examination Survey.

We investigated the association between obesity and cardiovascular disease risk factors (CVDRFs) in adolescents. We performed a cross-sectional study using the data from 8149 adolescents, aged 10-18 years, included in the Korean National Health and Nutrition Examination Survey (2011-2020). Using the body mass index, we defined "overweight" (≥85th to <95th percentile) and "obese" (≥95th percentile). We analyzed the associations between obesity and CVDRFs (high blood pressure, abnormal lipid profiles, and high fasting glucose levels) by sex and age groups (early [10-12 years], middle [13-15 years], and late [16-18 years] adolescence). When analyzing all the subjects, being overweight was correlated with high blood pressure and abnormal all-lipid profiles in boys and high triglyceride and low high-density lipoprotein cholesterol levels in girls, while obesity was associated with all CVDRFs in both boys and girls. Analyzing separately in the age subgroups, the correlation between obesity and CVDRFs tended to be shown earlier in boys than in girls, and obesity tended to be associated with CVDRFs earlier than being overweight. The association between obesity and CVDRFs may begin to be shown at different periods of youth, depending on the degree of obesity, CVDRF variables, and sex.

Association of blood pressure and hypertension between parents and offspring: The Korea National Health and Nutrition Examination Survey.

As the number of hypertension cases in the pediatric population is growing, we aimed to investigate the parent-offspring association of hypertension in Korea. We performed a cross-sectional analysis using the data of children and adolescents aged 10-18 years and their parents extracted from the Korea National Health and Nutrition Examination Survey (2008-2018). We analyzed the correlation of blood pressure (BP) between offspring and their parents and investigated the odds ratio (OR) of having hypertension in offspring based on parental hypertensive status. A total of 3996 children and adolescents (2224 boys and 1772 girls) aged 10-18 years and their parents (3197 fathers and 3197 mothers) were evaluated. Both boys and girls had positive associations with both parents for systolic and diastolic BP. When neither parent, only the father, only the mother, or both parents were hypertensive, 6.6%, 10.4%, 13.3%, and 25.3% of boys and 6%, 12%, 12.7%, and 22.1% of girls had hypertension, respectively. The risk of having hypertension among offspring was approximately two times higher when one parent was hypertensive and over four times higher when both parents were hypertensive compared to that among controls whose parents were not hypertensive (OR: 2.230, 1.655, and 5.021 in boys with hypertension and 2.321, 2.169, and 4.554 in girls with hypertension in the mother only, the father only, and both parents, respectively). We identified familial aggregation of hypertension in Korea. As there was an increased likelihood of having hypertension in children with parental hypertension, parental hypertension may be utilized as a screening tool for hypertension in children.

Case report: Myocarditis with nonsustained ventricular tachycardia following COVID-19 mRNA vaccination in a female adolescent.

Children with underlying medical conditions potentially develop severe illness from Coronavirus disease 2019 (COVID-19). The use of vaccines against COVID-19 is currently recommended for the pediatric population. The COVID-19 vaccine has a temporal association with the occurrence of myocarditis. Although most patients with COVID-19 vaccination-associated myocarditis (C-VAM) exhibit a mild clinical course and rapid recovery, C-VAM potentially causes electrical instability and sudden cardiac death. Herein, we report the case of a 17-year-old woman who presented with chest pain and syncope following the first dose of the messenger RNA COVID-19 vaccine. The patient's heart function was impaired, and nonsustained ventricular tachycardia was frequent. Cardiac magnetic resonance (CMR) imaging satisfied the criteria for myocarditis. Despite the administration of immunomodulatory drugs, the patient's heart function was not fully restored, and the concentration of cardiac enzymes remained above the normal range. Persistence of late gadolinium enhancement was observed on short-term follow-up CMR imaging. Although most patients with C-VAM exhibit mild symptoms, significant cardiac arrhythmias potentially occur. Furthermore, some patients with C-VAM demonstrate prolonged impaired heart function and sustained late gadolinium enhancement on follow-up CMR imaging. Therefore, monitoring of electrical and functional cardiac abnormalities in patients with C-VAM is crucial and the long-term outcomes and prognosis of patients with C-VAM require further investigation.

Nutrition, Body Composition, and Blood Pressure in Children and Adolescents from the Korea National Health and Nutrition Examination Survey.

We aimed to investigate the association between nutrition and blood pressure and the role that body composition plays in this relationship. Korea National Health and Nutrition Examination Survey data from the years 2008-2020 were reviewed. A total of 11,234 subjects (5974 boys and 5260 girls) aged 10-18 years of age were selected. We analyzed the correlation between nutrition (intakes of energy, protein, fat, carbohydrate, sodium, saturated fatty acid (SFA), unsaturated fatty acid (USFA), and dietary fiber (DF)) and body composition (height, weight, waist circumference (WC), body mass index (BMI), and waist to height ratio (WHtR)), and performed multiple regression analysis to find the independent correlation between body composition and blood pressure (BP). We then compared the correlation between nutrition and BP, with or without adjustment for body composition. The intakes of energy, protein, fat, carbohydrate, sodium, and USFA had positive associations with height, weight, WC, and BMI. Systolic BP (SBP) and diastolic BP (DBP) were independently positively correlated with height and BMI. The intakes of energy, protein, fat, carbohydrate, sodium, and SFA had positive correlations with SBP and DBP, which disappeared when additionally adjusted for BMI and height. In conclusion, nutrition seems to affect BP via height and BMI in Korean children and adolescents.

The compatibility of new blood pressure reference values for Korean children and adolescents with the US reference: the Korean Working Group of Pediatric Hypertension.

BACKGROUND: Childhood hypertension is associated with hypertension and metabolic syndrome in adulthood. Since the definition of childhood hypertension is based on the distribution of normative blood pressure (BP), a reference range is essential to create hypertension guidelines for children. We aimed to investigate the compatibility of the new Korean BP reference with the United States (US) BP reference based on the 2017 Clinical Practice Guideline. METHODS: We compared the new Korean reference BP values for children and adolescents aged 10 to 17 years with those in the 2017 Clinical Practice Guidelines. We also analyzed the differences in the prevalence of hypertension in Korean children and adolescents when reference value was applied. Considering Korean and US BP references together, linear trend lines were sought. RESULTS: Systolic BP (SBP) and diastolic BP (DBP) values in 95th percentiles showed no significant differences between the two BP references. Applying the two reference values, there was no significant difference in the prevalence of elevated BP and a combination of elevated BP and hypertension. Combining the Korean and US BP values and plotting them against age, approximate lines for the 90th and 95th SBP and DBP percentiles were observed. CONCLUSIONS: The BP values of the new Korean BP reference were similar to those of the US BP reference; they were reliable and interchangeable.

Relationship between Waist Circumference and Cardiovascular Risk Factors in Adolescents: Analysis of the Korea National Health and Nutrition Examination Survey Data.

BACKGROUND AND OBJECTIVES: High waist circumference (WC) is associated with increased cardiovascular risk (CVR) in adulthood. We investigated this association in adolescents. METHODS: We performed a cross-sectional analysis of data for 10-18-year-olds included in the Korea National Health and Nutrition Examination Survey (KNHANES) (2005-2014). The association between WC and CVR factors was evaluated. We analyzed this relationship according to age. RESULTS: We analyzed 8,153 participants (4,319 boys and 3,834 girls) from the KNHANES. High WC was associated with increased incidence of CVR factors: hypertension (odds ratio [OR], 3.5 in boys, 1.9 in girls), high total cholesterol (OR, 3.9 in boys, 1.9 in girls), high triglycerides (OR, 4.9 in boys, 3.2 in girls), high low-density lipoprotein (LDL) cholesterol (OR, 5.0 in boys, 1.8 in girls), low high-density lipoprotein (HDL) cholesterol (OR, 2.6 in boys, 3.0 in girls), and hyperglycemia (OR, 2.8 in girls). In boys, the association between high WC and hypertension, high triglycerides, and low HDL cholesterol was noted in early adolescence. High WC was associated with high total cholesterol and high LDL cholesterol in middle adolescence. In girls, high WC was correlated with high total cholesterol, high triglycerides, and low HDL cholesterol in early adolescence. High WC was shown to be associated with hyperglycemia in middle adolescence, and with hypertension and high LDL cholesterol in late adolescence. CONCLUSIONS: High WC in adolescents is associated with increased CVR. The timing of this association differs according to sex and CVR factors.

Blood Pressure Reference Values for Normal Weight Korean Children and Adolescents: Data from The Korea National Health and Nutrition Examination Survey 1998-2016: The Korean Working Group of Pediatric Hypertension.

BACKGROUND AND OBJECTIVES: Hypertension is becoming one of the most common health conditions in children and adolescents due to increasing childhood obesity. We aimed to provide the auscultatory blood pressure (BP) normative reference values for Korean non-overweight children and adolescents. METHODS: BP measurements in children and adolescents aged 10 to 18 years were performed in the Korean National Health and Nutrition Examination Survey (KNHANES) from 1998 to 2016. BP was measured using a mercury sphygmomanometer. Sex-, age- and height-specific systolic BP (SBP) and diastolic BP (DBP) percentiles were calculated in the non-overweight children (n=10,442). We used the General Additive Model for Location Scale and Shape method to calculate BP percentiles. RESULTS: The 50th, 90th, 95th, and 99th percentiles of SBP and DBP tables and graphs of non-overweight children and adolescents aged 10 to 18 years were presented by age and height percentiles. We found that the SBP and DBP at the 95th percentile were well correlated with height. The BP tables presented by height contained BP values from 124 cm to 190 cm for boys and from 120 cm to 178 cm for girls. Boys had higher SBP and DBP. CONCLUSIONS: We provided the sex-, age- and height-specific auscultatory BP values using the KNHANES big data. These may be useful in diagnosis and treatment of hypertension in Korean children and adolescents.

Hemodynamically balanced congenitally corrected transposition of the great arteries with a large ventricular septal defect, and subvalvular pulmonic stenosis: a case report.

BACKGROUND: Adults with unoperated congenitally corrected transposition of the great arteries are rare but form a distinct group among adults with congenital heart disease. Patients with congenitally corrected transposition of the great arteries often have one or more associated cardiac anomalies that dictate the need for, and timing of, surgical intervention in childhood. However, in a proportion of patients, the hemodynamics does not require surgical attention during childhood, and, in some patients, a correct diagnosis is not established until adulthood. Here we report an adult case of unoperated congenitally corrected transposition of the great arteries with a large ventricular septal defect and probable pulmonary arterial hypertension. CASE PRESENTATION: Our patient was a 46-year-old Korean man. Transthoracic echocardiography and cardiac catheterization demonstrated hemodynamically balanced ventricles with a non-regurgitant systemic atrioventricular valve, normal pulmonary arterial pressure, and a reasonable difference between the oxygen saturation values of the aorta and pulmonary trunk, even with the presence of a large ventricular septal defect. Further morphological assessments using cardiac computed tomography and three-dimensional modeling/printing of his heart revealed that the mitral valve was straddling over the posteriorly positioned ventricular septal defect, which could explain the functional and anatomical subvalvular pulmonary stenosis and a small amount of shunt flow through the large ventricular septal defect. We interpreted this combination of cardiac defects as able to sustain his stable cardiac function. Thus, we decided to maintain his unoperated status. CONCLUSION: A detailed anatomical understanding based on transthoracic echocardiography, cardiac computed tomography, and three-dimensional printing can justify a decision to not operate in cases of congenitally corrected transposition of the great arteries with hemodynamically balanced pulmonary stenosis and a ventricular septal defect, as observed in the present case.

A Survey of Parental Perception and Pattern of Action in Response to Influenza-like Illness in Their Children: Including Healthcare Use and Vaccination in Korea.

Seasonal influenza is a significant cause of morbidity and mortality of children in Korea. However, few data are available on parental perception and action toward childhood influenza. This study aimed to characterize parental perception and patterns of action in response to influenza and influenza-like illnesses (ILIs), including vaccination and healthcare use. This prospective study involved a random survey of parents whose children were aged 6-59 months. The survey was conducted in October 2014. The study included 638 parents of 824 children younger than 6 years. Most parental information of influenza came from mass media (28.2%) and social media (15.5%). The factor that most often motivated parents to vaccinate their children against influenza was promotion of the government or mass media (36.6%). Negative predictors of immunization included safety concerns about influenza vaccination (28.1%) and mistrust in the vaccine's effectiveness (23.3%). Therefore, correct information about influenza and vaccination from mass media will be one of the cornerstones for implementing a successful childhood immunization program and reducing morbidity and mortality in Korea. Furthermore, to enroll younger children in vaccination programs, and to minimize coverage gaps, public concerns about vaccine safety should be resolved. The demographic data in the present study will be used to provide a deeper insight into a parental perception and will help health care providers increase influenza immunization rate.

Medium- or Higher-Dose Acetylsalicylic Acid for Acute Kawasaki Disease and Patient Outcomes.

OBJECTIVE: To investigate the effect of medium- or higher-dose acetylsalicylic acid (ASA) for treating acute-phase Kawasaki disease to prevent coronary artery aneurysm (CAA). STUDY DESIGN: Among the children with acute Kawasaki disease investigated in the eighth nationwide survey in the Republic of Korea, 8456 children with adequate data were included in this study. The subjects were divided into 2 groups according to the use of medium- or higher-dose ASA (≥30 mg/kg/day), or-low dose ASA (3-5 mg/kg/day) during the acute febrile phase. Both z- score-based criteria and Japanese criteria for CAA were used. RESULTS: The prevalence of CAA based on z-score (24.8% vs 18.3%; P = .001) and on the Japanese criteria (19.0% vs 10.4%; P < .001) was higher in the 7947 patients who received medium- or higher-dose ASA compared with the 509 patients who received low-dose ASA. The use of medium- or higher-dose ASA was a significant predictor of CAA based on both sets of criteria by univariate analysis (based on z-score: OR, 1.472, 95% CI, 1.169-1.854, P = .001; based on Japanese criteria: OR, 2.013, 95% CI, 1.507-2.690, P < .001) and multivariate logistic regression analysis (OR, 1.527, 95% CI, 1.166-2.0, P = .003 and OR, 2.198, 95% CI, 1.563-3.092, P < .001, respectively). CONCLUSIONS: The use of medium- or higher-dose ASA in acute Kawasaki disease did not prevent CAA. A future randomized controlled trial is needed to determine the optimum dose of ASA.

Impact of lifestyle factors on trends in lipid profiles among Korean adolescents: the Korea National Health and Nutrition Examination Surveys study, 1998 and 2010.

PURPOSE: Only a few studies have explored nationwide trends in lipid profiles among Asian adolescents. We aimed to assess trends in lipid profiles and the associated lifestyle factors among Korean children. METHODS: We analyzed data for 2,094 adolescents who were aged 10-18 years and had participated in the Korea National Health and Nutrition Examination Surveys in 1998 and 2010. RESULTS: During 1998-2010, the prevalence of obesity significantly increased in boys, but no changes were observed in girls. Over this period, there was a small but significant decrease in the mean low-density lipoprotein (LDL)-cholesterol level in boys (1998, 87.5 mg/dL; 2010, 83.6 mg/dL; P=0.019) and mean triglyceride levels in girls (1998, 90.8 mg/dL; 2010, 85.8 mg/dL; P=0.020). There were no significant changes in the prevalence of dyslipidemia in boys, but a modest decrease was noted in girls (1998, 25.1%; 2010, 18.3%; P=0.052). During the study period, the prevalence of breakfast skipping decreased, whereas that of regular exercise increased in both groups. Daily total energy intake did not change between these years. In multivariable logistic regression analyses, breakfast skipping was associated with increased risk of hyper-LDL-cholesterolemia in boys (odds ratio [OR], 5.77) and hypertriglyceridemia (OR, 2.27) in girls. Regular exercise was associated with decreased risk of hypo-HDL-cholesterolemia (OR, 0.40) in boys. CONCLUSION: Although the prevalence of obesity in boys increased, favorable or constant trends in lipid profiles were observed among Korean adolescents during 1998-2010. Decrease in breakfast skipping and increase in regular exercise may have contributed to these trends.

Complications of Cardiac Catheterization in Structural Heart Disease.

BACKGROUND AND OBJECTIVES: Cardiac catheterization is used to diagnose structural heart disease (SHD) and perform transcatheter treatment. This study aimed to evaluate complications of cardiac catheterization and the associated risk factors in a tertiary center over 10 years. SUBJECTS AND METHODS: Total 2071 cardiac catheterizations performed at the Seoul National University Children's Hospital from January 2004 to December 2013 were included in this retrospective study. RESULTS: The overall complication, severe complication, and mortality rates were 16.2%, 1.15%, and 0.19%, respectively. The factors that significantly increased the risk of overall and severe complications were anticoagulant use before procedure (odds ratio [OR] 1.83, p=0.012 and OR 6.45, p<0.001, respectively), prothrombin time (OR 2.30, p<0.001 and OR 5.99, p<0.001, respectively), general anesthesia use during procedure (OR 1.84, p=0.014 and OR 5.31, p=0.015, respectively), and total procedure time (OR 1.01, p<0.001 and OR 1.02, p<0.001, respectively). Low body weight (OR 0.99, p=0.003), severe SHD (OR 1.37, p=0.012), repetitive procedures (OR 1.7, p=0.009), and total fluoroscopy time (OR 1.01, p=0.005) significantly increased the overall complication risk. High activated partial thromboplastin time (OR 1.04, p=0.001), intensive care unit admission state (OR 14.03, p<0.001), and concomitant electrophysiological study during procedure (OR 3.41, p=0.016) significantly increased severe complication risk. CONCLUSION: Currently, the use of cardiac catheterization in SHD is increasing and becoming more complex; this could cause complications despite the preventive efforts. Careful patient selection for therapeutic catheterization and improved technique and management during the peri-procedural period are required to reduce complications.

Impact of time to treatment of oseltamivir on influenza hospitalization cost among Korean children.

BACKGROUND: Although oseltamivir is a common influenza treatment, there is a lack of data on the economic benefits of timely oseltamivir treatment. METHODS: From February 2004 through June 2007, 116 hospitalized children ≤ 15 years of age with laboratory-confirmed influenza who received oseltamivir were identified via retrospective medical chart review. Demographic, clinical, and cost data were abstracted and multivariate linear regression was used to assess the association between oseltamivir time to treatment and treatment-related costs among hospitalized children with laboratory-confirmed influenza. RESULTS: Overall, 28% (n = 33) of patients were treated with oseltamivir ≥ day 3 of admission. Rapid influenza diagnostic test was used in a significantly lower proportion of patients treated with oseltamivir ≥ day 3 of admission compared with those who received oseltamivir earlier. On multivariate linear regression, initiation of oseltamivir ≥ day 3 of admission was associated with a 60.84% increase (95%CI: 32.59-95.11) in treatment-related hospital costs, compared with initiation on admission. CONCLUSION: Delayed initiation of oseltamivir was found to be associated with increased treatment-related hospital costs among children hospitalized with laboratory-confirmed influenza.

Sex differences in the relation of body composition to cardiovascular parameters and functions in Korean adolescents: a school-based study.

OBJECTIVE: Obesity in adolescence is associated with increased cardiovascular risk. The patterns of obesity and body composition differ between boys and girls. It is uncertain how body composition correlates with the cardiovascular system and whether such correlations differ by sex in adolescents. METHODS: Body composition (fat-free mass (FFM), adipose mass, waist circumference (WC)) and cardiovascular parameters and functions were studied in 676 healthy Korean adolescents aged 12-16 years. Partial correlation and path analyses were done. RESULTS: WC correlated with stroke volume (SV) and cardiac output (CO), systolic blood pressure (SBP) and pulse pressure (PP), cardiac diastolic function (ratio of early to late filling velocity (E/A ratio)), and vascular function (pulse wave velocity (PWV)) in boys. Adipose mass was related to SV, CO, SBP, PP, left ventricular mass (LVM), and PWV in girls - and to E/A ratio in both sexes. FFM affected SV, CO, SBP, and PP in both sexes and LVM in boys. Cardiac systolic functions had no relation with any body composition variable in either sex. CONCLUSION: In adolescence, the interdependence of the cardiovascular system and the body composition differs between sexes. Understanding of those relations is required to control adolescent obesity and prevent adult cardiovascular disease.

Development of a multiplex and cost-effective genotype test toward more personalized medicine for the antiplatelet drug clopidogrel.

There has been a wide range of inter-individual variations in platelet responses to clopidogrel. The variations in response to clopidogrel can be driven by genetic polymorphisms involved in the pathway of absorption, distribution, metabolism, excretion, and the target receptor P2Y12. A set of genetic variants known for causing variations in clopidogrel responses was selected, which included CYP2C19*2, *3, *17, CYP2B6*4, *6, *9, CYP3A4*18, CYP3A5*3, MDR1 2677G>T/A, 3435C>T, and P2Y12 H2 (742T>C). The simultaneous detection of these 10 variants was developed by using a multiplex PCR and single-base extension (MSSE) methodology. The newly developed genotyping test was confirmed by direct DNA sequencing in the representative positive control samples and validated in an extended set of 100 healthy Korean subjects. Genotyping results from the developed MSSE exhibited a perfect concordance with the direct DNA sequencing data and all of variants tested in 100 healthy Korean subjects were in agreement with Hardy-Weinberg equilibrium (p>0.05). The present molecular diagnostic studies provide an accurate, convenient, and fast genotyping method for the detection of multiple variants. This would be helpful for researchers, as well as clinicians, to use genetic information toward more personalized medicine of clopidogrel and other antiplatelet drugs in the future.

The association between influenza treatment and hospitalization-associated outcomes among Korean children with laboratory-confirmed influenza.

There are limited data evaluating the relationship between influenza treatment and hospitalization duration. Our purpose assessed the association between different treatments and hospital stay among Korean pediatric influenza patients. Total 770 children ≤ 15 yr-of-age hospitalized with community-acquired laboratory-confirmed influenza at three large urban tertiary care hospitals were identified through a retrospective medical chart review. Demographic, clinical, and cost data were extracted and a multivariable linear regression model was used to assess the associations between influenza treatment types and hospital stay. Overall, there were 81% of the patients hospitalized with laboratory-confirmed influenza who received antibiotic monotherapy whereas only 4% of the patients received oseltamivir monotherapy. The mean treatment-related charges for hospitalizations treated with antibiotics, alone or with oseltamivir, were significantly higher than those treated with oseltamivir-only (P < 0.001). Influenza patients treated with antibiotics-only and antibiotics/oseltamivir combination therapy showed 44.9% and 28.2%, respectively, longer duration of hospitalization compared to those treated with oseltamivir-only. Patients treated with antibiotics, alone or combined with oseltamivir, were associated with longer hospitalization and significantly higher medical charges, compared to patients treated with oseltamivir alone. In Korea, there is a need for more judicious use of antibiotics, appropriate use of influenza rapid testing.

The correlation of blood pressure with height and weight in Korean adolescents aged 10-19 years; The Korean National Health and Nutrition Examination Surveys (2009-2011).

PURPOSE: Height-specific blood pressure (BP) is the standard parameter used to diagnose childhood hypertension. However, there has been some argument that weight may be a better variable than height in the reference BP standards. Therefore, before assessing the BP status using the reference BP standards, a basic understanding of the fundamental association of weight and height with BP is required. METHODS: In the present study, we analyzed the correlation of BP with height and weight in Korean adolescents (age, 10-19 years), using data from the Korean National Health and Nutrition Examination Surveys (2009-2011). RESULTS: Systolic BP (SBP) was more closely correlated with weight than with height in the normal weight (body mass index [BMI], ≤85th percentile) and overweight (BMI, >85th percentile) groups and in the normal waist circumference (WC, ≤90th percentile) and high WC (>90th percentile) groups in both sexes. Diastolic BP (DBP) had a higher correlation with height than with weight in the normal weight and normal WC groups, whereas weight was more closely associated with DBP than height in the overweight and high WC groups in both boys and girls. CONCLUSION: In Korean adolescents, weight had a greater effect on SBP than height in both the normal weight and overweight groups. DBP was mainly affected by height in the normal weight group, whereas weight was the major determinant of DBP in the overweight group. Therefore, it may be necessary to consider weight in the establishment of reference BP standards.

The association of blood pressure with body mass index and waist circumference in normal weight and overweight adolescents.

PURPOSE: Overweight can be defined by the body mass index (BMI) and is likely associated with an increased cardiovascular disease risk. However, waist circumference (WC), a central adiposity index, may be a better indicator of cardiovascular disease risk. Studies comparing the effects of BMI and WC on cardiovascular risk factors, such as high blood pressure (BP), are rare in adolescents. METHODS: We analyzed the correlations of BMI and WC with BP in 3,363 Korean adolescents (aged 10-19 years), using data from the Korean National Health and Nutrition Examination Surveys (2009-2011). RESULTS: Systolic BP (SBP) in both sexes and diastolic BP (DBP) in boys were higher in the high BMI (>85th percentile) and high WC (>90th percentile) groups. High BMI and high WC were positively correlated with high SBP (>90th percentile) in both sexes, and high DBP (>90th percentile), in boys. BMI maintained its positive associations with SBP, DBP, high SBP, and high DBP in the normal weight (BMI≤85th percentile) and overweight (BMI>85th percentile) groups in both boys and girls, as well as in all subjects of both sexes, even after adjustment for WC. However, WC did not correlate with SBP, DBP, high SBP, or high DBP after adjustment for BMI in any group in either sex. CONCLUSION: In Korean adolescents, BMI correlated better with BP and high BP levels than WC. Further, BMI was positively associated with BP and high BP in the normal weight group as well as in the overweight group.

A Memory Molecule, Ca(2+)/Calmodulin-Dependent Protein Kinase II and Redox Stress; Key Factors for Arrhythmias in a Diseased Heart.

Arrhythmias can develop in various cardiac diseases, such as ischemic heart disease, cardiomyopathy and congenital heart disease. It can also contribute to the aggravation of heart failure and sudden cardiac death. Redox stress and Ca(2+) overload are thought to be the important triggering factors in the generation of arrhythmias in failing myocardium. From recent studies, it appears evident that Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) plays a central role in the arrhythmogenic processes in heart failure by sensing intracellular Ca(2+) and redox stress, affecting individual ion channels and thereby leading to electrical instability in the heart. CaMKII, a multifunctional serine/threonine kinase, is an abundant molecule in the neuron and the heart. It has a specific property as "a memory molecule" such that the binding of calcified calmodulin (Ca(2+)/CaM) to the regulatory domain on CaMKII initially activates this enzyme. Further, it allows autophosphorylation of T287 or oxidation of M281/282 in the regulatory domain, resulting in sustained activation of CaMKII even after the dissociation of Ca(2+)/CaM. This review provides the understanding of both the structural and functional properties of CaMKII, the experimental findings of the interactions between CaMKII, redox stress and individual ion channels, and the evidences proving the potential participation of CaMKII and oxidative stress in the diverse arrhythmogenic processes in a diseased heart.

The relationships of body mass index, waist-to-height ratio, and body fat percentage with blood pressure and its hemodynamic determinants in Korean adolescents: a school-based study.

PURPOSE: Obesity is an important risk factor for hypertension in adolescents. We investigated the relationship of obesity-related indices (body mass index [BMI], waist-to-height ratio [WHR], and body fat percentage [%BF]) with blood pressure and the hemodynamic determinants of blood pressure in Korean adolescents. METHODS: In 2008, 565 adolescents, aged 12-16 years, were examined. The %BF of the participants was measured by bioelectrical impedance analysis. Echocardiography and brachial artery pulse tracing were used to estimate the stroke volume (SV), cardiac output (CO), total vascular resistance (TVR), and total arterial compliance (TAC). RESULTS: We noted that BMI, WHR, and %BF were positively correlated with systolic blood pressure (SBP) and diastolic blood pressure (DBP). The positive correlation between BMI and blood pressure (SBP and DBP) persisted after adjustment for WHR and %BF. However, after adjustment for BMI, the positive associations between blood pressure (SBP and DBP) and WHR as well as %BF, were not noted. With regard to the hemodynamic factors, BMI, but not WHR and %BF, was an independent positive factor correlated with SV and CO. TVR had an independent negative association with BMI; however, it was not associated with WHR or %BF. Moreover, we noted that BMI, WHR, and %BF did not affect TAC. CONCLUSION: In Korean adolescents, BMI had an independent positive correlation with SBP and DBP, possibly because of its effects on SV, CO, and TVR. WHR and %BF are believed to indirectly affect SBP and DBP through changes in BMI.