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Mental health and nutritional intake according to sleep duration in adolescents - Based on the 2007-2016 Korea National Health and Nutrition Examination Survey - (청소년들의 수면시간에 따른 정신건강 및 영양섭취 상태 - 국민건강영양조사(2007-2016년)자료를 이용하여 -)

  • Ki, Ye Jin;Kim, Yookyung;Shin, Woo-Kyoung
    • Journal of Korean Home Economics Education Association
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    • v.30 no.4
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    • pp.1-14
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    • 2018
  • The purpose of this study was to examine the relevance of mental health and nutritional intake according to the sleep duration of Korean adolescents. This study was based on data from the 2007-2016 Korea National Health and Nutrition Examination Survey(KNHNES), including 5,489 total subjects (2,795 middle school students, 2,694 high school students). The association between sleep duration and mental health was analyzed using a logistic regression analysis, and the link between sleep duration and nutritional intake was analyzed via a generalized linear model. An analysis of sleep duration showed that middle school students had a higher average sleep duration than high school students (P<0.0001). An analysis of the relationship between sleep duration and mental health showed that middle school students had lower rates of stress perception (P<0.0001) and suicidal ideation (P=0.0005) as their sleep duration increased. High school students had 53% less suicidal ideation in the group getting 6-7 hours compared to the group getting less than 6 hours, and 37% less suicidal ideation than the group getting 7-8 hours. The link between sleep duration and stress perception was statistically significant among both middle and high school students (P for interaction=0.02). An analysis of the daily intake of major nutrients according to sleep hours found high intake of vitamin C in groups where high school students slept more than nine hours (P=0.003). The state of nutritional intake according to higher sleep duration showed statistically significant differences between higher intake of phosphorus, riboflavin, niacin, and vitamin C in Nutrient Adequacy Ratio for high school students. In conclusion, adolescents' sleep duration is associated with stress perception, suicidal ideation and nutritional intake. Therefore, this study emphasizes the mental importance of adolescent sleep and can be used as a basis for nutrition education.

A Study of Dopamine Transporter Imaging and Comparison of Noninvasive Simplified Quantitative Methods in Normal Controls and Parkinson's Patients ([I-123]IPT SPECT를 이용한 정상인과 파킨슨 환자의 도파민 운반체의 영상화 및 단순화된 정량분석 방법들의 비교연구)

  • Bong, Jung-Kyun;Kim, Hee-Joung;Im, Joo-Hyuck;Yang, Seoung-Oh;Moon, Dae-Hyuk;Ryu, Jin-Sook;Nam, Ki-Pyo;Cheon, Jun-Hong;Kwon, Soo-Il;Lee, Hee-Kyung
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.3
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    • pp.315-324
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    • 1996
  • The purpose of this study was to compare the specific binding ratio method with model-based methods in estimating the transporter parameter $k_3/k_4$ in normal controls and Parkinson's patients with [I-123]IPT SPECT and to evaluate the usefulness of [I-123]IPT SPECT. $6.5{\pm}1.1$ mCi ($239.0{\pm}40.3$ MBq) of [$^{123}I$]IPT was intravenouly injected as a bolus into six normal controls(age:$45{\pm}13$) and seventeen patients(age:$55{\pm}8$) with Pakinson's disease(PD). The transporter parameter $k_3/k_4$ was derived using the Ichise's graphical method($R_v$) and Lassen's area ratio method($R_A$) for the dynamic IPT SPECT data without blood samples. Then, the relationships between the transporter parameter $R-v,\;R_A$ and the ratio of (BG-OCC)/OCC at 115 minutes were evaluated by linear regression analysis. $R_vs$ by Ichise's graphical method for NC and PD were $2.08{\pm}0.29$ and $0.78{\pm}0.31$, respectively. $R_As$ by Lassen's area ratio method for NC and PD were $1.48{\pm}0.16$ and $0.65{\pm}0.24$, respectively. The correlation coefficients between (BG-OCC)/OCC and $R_v$, (BG-OCC)/OCC and $R_A$, and $R_v$ and $R_A$ were 0.93, 0.90, 0.99 and their corresponding slopes were 0.54, 0.34, and 0.65, respectively. The $R_v$ and $R_A$ of NC were significantly higher than the ones of PD. That is, the $k_3/k_4$ of NC was clearly separated from the one of PD. $k_3/k_4$ showed a good correlation with the ratio of (BG-OCC)/OCC. The results indicate that the noninvasive simplified quantitative methods may be useful to measure the transporter parameter $k_3/k_4$ and the specific binding ratio method can be used for quantitative studies of dopamine transporter with [I-123]IPT SPECT in humans brains.

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The Variations of Stratospheric Ozone over the Korean Peninsula 1985~2009 (한반도 상공의 오존층 변화 1985~2009)

  • Park, Sang Seo;Kim, Jhoon;Cho, Nayeong;Lee, Yun Gon;Cho, Hi Ku
    • Atmosphere
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    • v.21 no.4
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    • pp.349-359
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    • 2011
  • The climatology in stratospheric ozone over the Korean Peninsula, presented in previous studies (e.g., Cho et al., 2003; Kim et al., 2005), is updated by using daily and monthly data from satellite and ground-based data through December 2009. In addition, long-term satellite data [Total Ozone Mapping Spectrometer (TOMS), Ozone Monitoring Instrument (OMI), 1979~2009] have been also analyzed in order to deduce the spatial distributions and temporal variations of the global total ozone. The global average of total ozone (1979~2009) is 298 DU which shows a minimum of about 244 DU in equatorial latitudes and increases poleward in both hemispheres to a maximum of about 391 DU in Okhotsk region. The recent period, from 2006 to 2009, shows reduction in total ozone by 6% relative to the values for the pre-1980s (1979~1982). The long-term trends were estimated by using a multiple linear regression model (e.g., WMO, 1999; Cho et al., 2003) including explanatory variables for the seasonal variation, Quasi-Biennial Oscillation (QBO) and solar cycle over three different time intervals: a whole interval from 1979 to 2009, the former interval from 1979 to 1992, and the later interval from 1993 to 2009 with a turnaround point of deep minimum in 1993 is related to the effect of Mt. Pinatubo eruption. The global trend shows -0.93% $decade^{-1}$ for the whole interval, whereas the former and the later interval trends amount to -2.59% $decade^{-1}$ and +0.95% $decade^{-1}$, respectively. Therefore, the long-term total ozone variations indicate that there are positive trends showing a recovery sign of the ozone layer in both North/South hemispheres since around 1993. Annual mean total ozone (1985~2009) is distributed from 298 DU for Jeju ($33.52^{\circ}N$) to 352 DU for Unggi ($42.32^{\circ}N$) in almost zonally symmetric pattern over the Korean Peninsula, with the latitudinal gradient of 6 DU $degree^{-1}$. It is apparent that seasonal variability of total ozone increases from Jeju toward Unggi. The annual mean total ozone for Seoul shows 323 DU, with the maximum of 359 DU in March and the minimum of 291 DU in October. It is found that the day to day variability in total ozone exhibits annual mean of 5.7% in increase and -5.2% in decrease. The variability as large as 38.4% in increase and 30.3% in decrease has been observed, respectively. The long-term trend analysis (e.g., WMO, 1999) of monthly total ozone data (1985~2009) merged by satellite and ground-based measurements over the Korean Peninsula shows increase of 1.27% $decade^{-1}$ to 0.80% $decade^{-1}$ from Jeju to Unggi, respectively, showing systematic decrease of the trend magnitude with latitude. This study also presents a new analysis of ozone density and trends in the vertical distribution of ozone for Seoul with data up to the end of 2009. The mean vertical distributions of ozone show that the maximum value of the ozone density is 16.5 DU $km^{-1}$ in the middle stratospheric layer between 24 km and 28 km. About 90.0% and 71.5% of total ozone are found in the troposphere and in the stratosphere between 15 and 33 km, respectively. The trend analysis reconfirms the previous results of significant positive ozone trend, of up to 5% $decade^{-1}$, in the troposphere and the lower stratosphere (0~24 km), with negative trend, of up to -5% $decade^{-1}$, in the stratosphere (24~38 km). In addition, the Umkehr data show a positive trend of about 3% $decade^{-1}$ in the upper stratosphere (38~48 km).

A Study on the DWI and Pathologic Findings of Cancer Cells (암 세포주의 확산강조영상과 병리학적 관계에 관한 연구)

  • Seong, Jae-Gu;Lim, Cheong-Hwan
    • Journal of radiological science and technology
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    • v.34 no.3
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    • pp.239-244
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    • 2011
  • In this study, we evaluated diffusion weighted imaging (DWI) to investigate whether the DWI parameters can predict characteristic parameters on pathologic specimens of tumor or not. CFPAC-1 was injected subcutaneously on the back flank of athymic nude mice (n=13) then two tumors were initiated on each mouse (2${\times}$13=26 tumors). The mice were sacrificed to make specimen immediately after initial MR imaging then were compared with the MR image. A dedicated high-field (7T) small-animal MR scanner was used for image acquisitions. A T1 and T2 weighted axial image using RARE technique was acquired to measure the T2 values and tumor size. DWI MR was performed for calculating ADC values. To evaluate tumor cellularity and determine the levels of MVD, tumor cells were excised and processed for H-E staining and immunostaining using CD31. T2 values and ADC values were computed and analyzed for each half of the tumors and compared to the correlated specimens slide. Median ADC within each half of mass was compared to the cellularity and MVD in the correlated area of pathologic slide. The mean of ADC value is $0.7327{\times}10^{-3}$ $mm^2/s$ and standard deviation is $0.1075{\times}10^{-3}$ $mm^2/s$. There is a linear relationship between ADC value and tumor necrosis (R2=0.697, p< 0.001). DW image parameters including the ADC values can be utilized as surrogate markers to assess intratumoral neoangiogenesis and change of the internal structure of tumor cells.

Estimation of Surface Solar Radiation using Ground-based Remote Sensing Data on the Seoul Metropolitan Area (수도권지역의 지상기반 원격탐사자료를 이용한 지표면 태양에너지 산출)

  • Jee, Joon-Bum;Min, Jae-Sik;Lee, Hankyung;Chae, Jung-Hoon;Kim, Sangil
    • Journal of the Korean earth science society
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    • v.39 no.3
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    • pp.228-240
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    • 2018
  • Solar energy is calculated using meteorological (14 station), ceilometer (2 station) and microwave radiometer (MWR, 7 station)) data observed from the Weather Information Service Engine (WISE) on the Seoul metropolitan area. The cloud optical thickness and the cloud fraction are calculated using the back-scattering coefficient (BSC) of the ceilometer and liquid water path of the MWR. The solar energy on the surface is calculated using solar radiation model with cloud fraction from the ceilometer and the MWR. The estimated solar energy is underestimated compared to observations both at Jungnang and Gwanghwamun stations. In linear regression analysis, the slope is less than 0.8 and the bias is negative which is less than $-20W/m^2$. The estimated solar energy using MWR is more improved (i.e., deterministic coefficient (average $R^2=0.8$) and Root Mean Square Error (average $RMSE=110W/m^2$)) than when using ceilometer. The monthly cloud fraction and solar energy calculated by ceilometer is greater than 0.09 and lower than $50W/m^2$ compared to MWR. While there is a difference depending on the locations, RMSE of estimated solar radiation is large over $50W/m^2$ in July and September compared to other months. As a result, the estimation of a daily accumulated solar radiation shows the highest correlation at Gwanghwamun ($R^2=0.80$, RMSE=2.87 MJ/day) station and the lowest correlation at Gooro ($R^2=0.63$, RMSE=4.77 MJ/day) station.

The Effect of Body Mass Index, Fat Percentage, and Fat-free Mass Index on Pulmonary Function Test -With Particular Reference to Parameters Derived from Forced Expiratory Volume Curve- (신체질량지수 및 체지방률, 그리고 제지방지수가 폐기능 검사에 미치는 영향 -노력성 호기곡선을 중심으로-)

  • Park, Ji Young;Pack, Jong Hae;Park, Hye Jung;Bae, Seong Wook;Shin, Kyeong Cheol;Chung, Jin Hong;Lee, Kwan Ho
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.2
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    • pp.210-218
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    • 2003
  • Background : Sex specific cross sectional reference values for the lung function indices usually employ a linear model with a term for age and height. The purpose of this study was to determine the effects of the body mass index (BMI), the fat percentage of the body mass and the fat-free mass index (FFMI) on the forced expiratory volume curve. Methods : Between January 2000 and December 2001, a total of 300 subjects, 150 men and 150 women (mean age : $45{\pm}13$ years), with a normal lung function were enrolled in the study sample. This study measured the $FEV_1$, FVC and $FEF_{25-75%}$ from the forced expiratory volume curve by a spirometer and the body composition by a bioelectrical impedance method in all subjects. Multiple regression analysis was used in order to examine the effects of the body composition on the parameters derived from the forced expiratory volume curve. Results : After adjusting for age, the BMI and Fat percentage improved the descriptions of the FVC (p<0.05, $r^2=0.491$) and $FEV_1$ (p<0.05, $r^2=0.654$) in women. In contrast, the FFMI contributed significantly to the FVC (p<0.05, $r^2=0.432$) and $FEV_1$ (p<0.05, $r^2=0.567$) in men. The $FEF_{25-75%}$ correlated with the fat percentage in women (p<0.05, $r^2=0.337$). Conclusion : These results suggest that the BMI, the fat percentage and the FFMI are significant determinants of the forced expiratory volume curve. The plmonary function test, when considering the BMI, the fat percentage and the FFMI, might be useful in clinical applications.

A Study on the Evaluative Models and Indicators for Diagnosis of Urban Visual Landscape - Focusing on Seoul City - (도시경관 진단을 위한 평가모델 및 지표개발 연구 - 서울시를 중심으로 -)

  • Kim, Seung-Ju;Im, Seung-Bin
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.1
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    • pp.78-86
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    • 2009
  • Recently, there seems to besome problems in the urban visual landscape as a result of continuous economic growth and industrial development. At the same time, the public has begun to be aware of the importance of visual resources, and the necessity for visual landscape conservation and improvement. Therefore, the development of evaluative indicators for systematic visual landscape planning and design is urgent. The purpose ofthis study is to discover evaluative models and indicators for the diagnosis of urban visual landscapes. This study included the selection of 18 physical indicators(statistical data) by literature reviews, adoption of field and questionnaire surveys at 12 autonomous districts in Seoul and surrounding major mountain valleys and river streams(i.e. Mt. Nam and Han-River). The content of the questionnaire is scenic beauty. Moreover, the linear regression analysis between the scenic beauty mean scores and the physical indicator scores figure out the scenic beauty prediction model. As this study suggests, the most important indicators in urban visual landscapes are 'Greens', 'Park' and 'the number of apartment buildings(higher than 20 stories).' Based on the results, greens and parks should be priority elements to considerin urban landscape planning and design. Moreover, since the number of apartment buildings that are higher than 20 stories has a negative correlation with the scenic beauty score, it can be used as basic data for landscape planning. For the scenic beauty prediction models and evaluative indicators suggest a direction of urban management, each indicator becomes basic data for visual landscape planning and design. In following studies, if physical indicators and case studies are added, the scenic beauty prediction models and evaluative indicators could be more synthetic and systematic. Moreover, the development of physical indicators in three dimensions(3D)(i.e. results from visual district analysis, view surface analysis) could be expected to obtain more general and varied results.

Comparison of chronic disease risk by dietary carbohydrate energy ratio in Korean elderly: Using the 2007-2009 Korea National Health and Nutrition Examination Survey (한국 노인 식사의 탄수화물 에너지비에 따른 만성질환 위험성 비교: 2007~2009년 국민건강영양조사 자료 이용)

  • Park, Min Seon;Suh, Yoon Suk;Chung, Young-Jin
    • Journal of Nutrition and Health
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    • v.47 no.4
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    • pp.247-257
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    • 2014
  • Purpose: It is reported that most senior people consume a high carbohydrate diet, while a high carbohydrate diet could contribute to the risk of chronic disease. The aim of this study is to determine whether a high carbohydrate diet can increase the risk of chronic disease in elderly Koreans. Methods: Using the 2007-2009 Korean National Health Nutrition Examination Survey data, out of a total of 3,917 individuals aged 65 and above, final 1,535 subjects were analyzed, divided by dietary carbohydrate energy ratio into two groups of moderate carbohydrate ratio (MCR, 55-70%) and excessive carbohydrate ratio (ECR, > 70%). All data were processed after the application of weighted value, using a general linear model or logistic regression. Results: Eighty one percent of elderly Koreans consumed diets with carbohydrate energy ratio above 70%. The ECR group included more female subjects, rural residents, lower income, and lower education level. The ECR group showed lower waist circumference, lower diastolic blood pressure, and lower frequency of consumption of meat and egg, milk, and alcohol. The intake of energy and most nutrients, with the exception of fiber, potassium, vitamin A, and carotene, was lower in the ECR group compared to the MCR group. When analyzed by gender, the ECR group showed lower risk of dyslipidemia in male and obesity in female subjects, even though the ECR group showed low intake of some nutrients. No difference in the risk of hypertension, diabetes, and anemia was observed between the two groups in male or female subjects. Conclusion: This result suggested that a high carbohydrate diet would not be a cause to increase the risk of chronic disease in the elderly. Further study is needed in order to determine an appropriate carbohydrate energy ratio for elderly Koreans to reduce the risk of chronic disease.

Development of a Test Method for the Evaluation of DNA Damage in Mouse Spermatogonial Stem Cells

  • Jeon, Hye Lyun;Yi, Jung-Sun;Kim, Tae Sung;Oh, Youkyung;Lee, Hye Jeong;Lee, Minseong;Bang, Jin Seok;Ko, Kinarm;Ahn, Il Young;Ko, Kyungyuk;Kim, Joohwan;Park, Hye-Kyung;Lee, Jong Kwon;Sohn, Soo Jung
    • Toxicological Research
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    • v.33 no.2
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    • pp.107-118
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    • 2017
  • Although alternative test methods based on the 3Rs (Replacement, Reduction, Refinement) are being developed to replace animal testing in reproductive and developmental toxicology, they are still in an early stage. Consequently, we aimed to develop alternative test methods in male animals using mouse spermatogonial stem cells (mSSCs). Here, we modified the OECD TG 489 and optimized the in vitro comet assay in our previous study. This study aimed to verify the validity of in vitro tests involving mSSCs by comparing their results with those of in vivo tests using C57BL/6 mice by gavage. We selected hydroxyurea (HU), which is known to chemically induce male reproductive toxicity. The 50% inhibitory concentration ($IC_{50}$) value of HU was 0.9 mM, as determined by the MTT assay. In the in vitro comet assay, % tail DNA and Olive tail moment (OTM) after HU administration increased significantly, compared to the control. Annexin V, PI staining and TUNEL assays showed that HU caused apoptosis in mSSCs. In order to compare in vitro tests with in vivo tests, the same substances were administered to male C57BL/6 mice. Reproductive toxicity was observed at 25, 50, 100, and 200 mg/kg/day as measured by clinical measures of reduction in sperm motility and testicular weight. The comet assay, DCFH-DA assay, H&E staining, and TUNEL assay were also performed. The results of the test with C57BL/6 mice were similar to those with mSSCs for HU treatment. Finally, linear regression analysis showed a strong positive correlation between results of in vitro tests and those of in vivo. In conclusion, the present study is the first to demonstrate the effect of HU-induced DNA damage, ROS formation, and apoptosis in mSSCs. Further, the results of the current study suggest that mSSCs could be a useful model to predict male reproductive toxicity.

Plasma Levels of High Molecular Weight Adiponectin are Associated with Cardiometabolic Risks in Patients with Hypertension (고혈압 환자에서 혈장 고분자량 아디포넥틴 농도와 심장-대사위험인자와의 관련성 연구)

  • Chung, Hye-Kyung;Shin, Min-Jeong
    • Journal of Nutrition and Health
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    • v.41 no.8
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    • pp.733-741
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    • 2008
  • In the present study, we comprehensively examined the associations of plasma levels of total adiponectin and high molecular weight (HMW) adiponectin with the features of cardiometabolic risks including body fat distribution, dyslipidemia, insulin resistance and inflammatory markers in a cross-sectional study of 110 treated hypertensive patients. Blood lipid profiles, high sensitivity C-reactive protein (hsCRP) and homeostasis model assessment of insulin resistance (HOMA- IR) derived from fasting glucose and insulin concentrations were determined. Plasma levels of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1) were analyzed using ELISA. The results showed that plasma levels of HMW-adiponectin were negatively associated with body mass index (BMI, r = - 0.203, p < 0.05) and waist circumference (r = -0.307, p < 0.01), which was not shown in total adiponectin. Plasma levels of HMW-adiponectin were negatively associated with triglyceride (r = -0.223, p < 0.05) and positively associated with HDL-cholesterol (r = 0.228, p < 0.05). Plasma levels of adiponectin were positively associated with HDL-cholesterol (r = 0.224, p < 0.05). Plasma levels of HMW-adiponectin were negatively associated with hsCRP (r = -0.276, p < 0.01) and IL-6 (r = -0.272, p < 0.01). In addition, there were weak associations between plasma levels of HMWadiponectin and TNF-${\alpha}$ (r = -0.163, p = 0.07) and ICAM-1 (r = -0.158, p = 0.09). However, there were no significant associations of total adiponectin with inflammatory markers except hsCRP (r = -0.203, p < 0.05). Stepwise multiple linear regression analysis showed that only plasma levels of HMW-adiponectin was an independent factor influencing serum levels of hsCRP, a marker of systemic low grade inflammation, after adjusting for age, gender, BMI, waist circumference, alcohol intake, smoking status, blood lipids, total adiponectin and drug use (p < 0.01). These results suggest that HMW-adiponectin, rather than total adiponectin, is likely to be closely associated with the features of cardiometabolic risks in treated hypertensive patients and might be effective biomarker for the prediction of cardiovascular disease.