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Journals of Gerontology Series A-biological Sciences and Medical Sciences | 2012

Prevalence of Sarcopenia and Sarcopenic Obesity in the Korean Population Based on the Fourth Korean National Health and Nutritional Examination Surveys

Young-Sang Kim; Yunhwan Lee; Yoon-Sok Chung; Duck-Joo Lee; Nam-Seok Joo; Doohee Hong; Go eun Song; Hyeon-Jeong Kim; Yong Jun Choi; Kwang-Min Kim

BACKGROUND Sarcopenia is an important factor of functional impairment related to aging. This study is conducted to investigate the prevalence of sarcopenia and sarcopenic obesity in Korean population. METHODS Representative Korean men (4,486) and women (5,999) aged 20 years or older were analyzed from the Fourth Korean National Health and Nutritional Examination Surveys. Sarcopenia was classified into Class I defined relative skeletal muscle mass loss within 1-2 SD of the gender-specific mean for healthy young adults and Class II below 2 SD. Relative skeletal muscle mass was represented by the appendicular skeletal muscle mass adjusted by height and body weight. Sarcopenic obesity was considered present in Class II sarcopenic participants whose waist circumference was more than or equal to 90 cm for men and more than or equal to 85 cm for women, respectively. RESULTS The prevalence of Class II sarcopenia in the Korean elderly population was 12.4% for men and 0.1% for women by height-adjusted definition and 9.7% for men and 11.8% for women by weight-adjusted definition. The prevalence of sarcopenic obesity was 7.6% for men and 9.1% for women by weight-adjusted definition but nearly zero for men and women by height-adjusted definition. The prevalence of sarcopenia increased with age for men but for women only when applied with weight-adjusted definition. CONCLUSIONS The prevalence of sarcopenia and sarcopenic obesity differs by gender and definition criteria. The height-adjusted definition may tend to underestimate the prevalence of sarcopenia and sarcopenic obesity, especially in women.


Journal of Telemedicine and Telecare | 2007

Mobile phone short message service messaging for behaviour modification in a community-based weight control programme in Korea:

Nam-Seok Joo; Bom-Taeck Kim

We conducted a community-based anti-obesity programme using mobile phone short message service (SMS) messaging. A total of 927 participants were recruited and visited a public health centre for initial assessment. Mobile phones were used to deliver short messages about diet, exercise and behaviour modification once a week. After a 12-week anti-obesity programme they visited the public health centre again. Four hundred and thirty-three subjects (47%) successfully completed their weight control programme. There were mean reductions of weight, waist circumference and body mass index of 1.6 kg (P < 0.001), 4.3 cm (P < 0.001) and 0.6 kg/m2 (P < 0.001), respectively. Over two-thirds of the subjects had a reduction in waist circumference of 5–7.5 cm. A post-intervention survey showed that the majority of participants were satisfied with the weekly SMS messages and information brochures delivered by post. SMS messaging may be an effective method of behaviour modification in weight control and anti-obesity health education programmes when promoted by community health centres.


Biological Trace Element Research | 2009

Hair iron and other minerals' level in breast cancer patients.

Nam-Seok Joo; Sang-Man Kim; Yongsik Jung; Kwang-Min Kim

Little is known about hair minerals in cancer patients, and serum iron level has been shown to be elevated in breast cancer patients. Therefore, the aim of this study was to evaluate hair iron and hair minerals’ level related to hair iron in breast cancer patients compared to controls. We compared hair mineral analysis data of 40 breast cancer subjects with age and body mass index-matched normal control data (n = 144) by cross-sectional analysis. All breast cancer patients were newly diagnosed at one Breast Cancer Center in Ajou University and had their hair cut before anti-cancer chemotherapy, and the normal controls (without breast cancer) also had their hair cut for various reasons in out-patient clinics of the Department of Family Practice and Community Health. Breast cancer patients had low calcium, magnesium, iron, copper, manganese, and zinc, whereas they had high arsenic, sodium, and potassium compared with the normal control. The hair iron level was positively correlated with hair calcium (r = 0.761, P < 0.001), magnesium (r = 0.643, P < 0.001), and manganese (r = 0.550, P < 0.001) and negatively correlated with arsenic (r = −0.537, P < 0.001). The hair iron level was significantly associated with the hair calcium (β = 0.778, P < 0.001) and manganese (β = 0.240, P < 0.001) by using multiple linear regression analysis. We observed different hair mineral patterns in breast cancer patients compared to normal controls. Especially, hair iron level was significantly reduced and associated with hair calcium and manganese levels.


Nutrition Research and Practice | 2014

Biological functions of histidine-dipeptides and metabolic syndrome

Byeng Chun Song; Nam-Seok Joo; Giancarlo Aldini; Kyung-Jin Yeum

The rapid increase in the prevalence of metabolic syndrome, which is associated with a state of elevated systemic oxidative stress and inflammation, is expected to cause future increases in the prevalence of diabetes and cardiovascular diseases. Oxidation of polyunsaturated fatty acids and sugars produces reactive carbonyl species, which, due to their electrophilic nature, react with the nucleophilic sites of certain amino acids. This leads to formation of protein adducts such as advanced glycoxidation/lipoxidation end products (AGEs/ALEs), resulting in cellular dysfunction. Therefore, an effective reactive carbonyl species and AGEs/ALEs sequestering agent may be able to prevent such cellular dysfunction. There is accumulating evidence that histidine containing dipeptides such as carnosine (β-alanyl-L-histidine) and anserine (β-alanyl-methyl-L-histidine) detoxify cytotoxic reactive carbonyls by forming unreactive adducts and are able to reverse glycated protein. In this review, 1) reaction mechanism of oxidative stress and certain chronic diseases, 2) interrelation between oxidative stress and inflammation, 3) effective reactive carbonyl species and AGEs/ALEs sequestering actions of histidine-dipeptides and their metabolism, 4) effects of carnosinase encoding gene on the effectiveness of histidine-dipeptides, and 5) protective effects of histidine-dipeptides against progression of metabolic syndrome are discussed. Overall, this review highlights the potential beneficial effects of histidine-dipeptides against metabolic syndrome. Randomized controlled human studies may provide essential information regarding whether histidine-dipeptides attenuate metabolic syndrome in humans.


Environmental Toxicology | 2015

Elevated serum ferritin and mercury concentrations are associated with hypertension; analysis of the fourth and fifth Korea national health and nutrition examination survey (KNHANES IV-2, 3, 2008-2009 and V-1, 2010).

Beomhee Choi; Kyung-Jin Yeum; Soo-Jung Park; Kyu-Nam Kim; Nam-Seok Joo

The impact of simultaneously elevated serum ferritin and mercury concentrations on hypertension in the general population is not known. To determine the association of serum ferritin and mercury concentrations with hypertension, 6213 subjects (3060 men and 3153 women) over 20 years of age from 2008 to 2010 Korea National Health and Nutrition Examination Survey were divided into tertiles according to serum ferritin and mercury concentrations in each gender. Serum ferritin (258.2 vs. 94.8 pmol/L) and mercury concentrations (28.4 vs. 19.9 nmol/L) were higher in men than in women. Serum ferritin (men; P = 0.029, women; P < 0.001) and mercury (men; P < 0.001, women; P = 0.003) concentrations were significantly associated with the prevalence of hypertension. In addition, significant correlation between serum ferritin and mercury concentrations in both men (r = 0.193, P < 0.001) and women (r = 0.145, P < 0.001) were found. Also, the increase of serum ferritin concentrations were more prominent in men (P < 0.001) than in women (P = 0.017) as the serum mercury tertiles increased after proper adjustments. Furthermore, significantly higher odds ratios of hypertension were found in the second (OR = 1.86, 95% CI; 1.05–3.30), and third (OR = 1.84, 95% CI; 1.01–3.36) tertiles of serum ferritin with the top tertile of serum mercury in men. The current study indicate that serum ferritin and mercury concentrations are associated with the prevalence of hypertension and that simultaneously elevated serum ferritin and mercury concentrations are related to the risk for hypertension in men.


Yonsei Medical Journal | 2014

Different Location of Triaxial Accelerometer and Different Energy Expenditures

Do Yoon Kim; Yoo-Suk Jung; Rae Woong Park; Nam-Seok Joo

Purpose We performed a study to determine the best appropriate wearing site of a triaxial accelerometer at different exercise speeds. Materials and Methods We conducted an observational study with 66 healthy Korean adults (26 men and 40 women). Resting metabolic rate (RMR) before exercise, physical activity-related energy expenditure (PAEE) by cardiorespiratory gas analyzer and Signal Vector Magnitude (SVM) were measured while wearing four triaxial accelerometers on four different sites (wrist, waist, upper arm, and ankle) at exercise speeds from 2-10 km/h. Results The mean RMR was 4.03 mL/kg/min and Actual METs (oxygen consumption at different exercise speeds divided by individual RMR) compared with the calculated METs (oxygen consumption divided by 3.5 mL/kg/min) showed relatively low value. The overall correlation between PAEE and SVM was highest when the accelerometer was worn on the wrist at low exercise speed (r=0.751, p<0.001), waist at a moderate speed (r=0.821, p<0.001), and ankle at a high speed (r=0.559, p<0.001). Using regression analysis, it was shown that the ankle at a low speed (R2=0.564, p<0.001), high speed (R2=0.559, p<0.001), and the waist at a moderate speed (R2=0.821, p<0.001) were the best appropriate sites. Conclusion When measuring the PAEE and SVM at different exercise speeds, the ankle in low and high exercise speed, and waist in moderate speed are the most appropriate sites for an accelerometer.


Biological Trace Element Research | 2014

Serum Zinc Concentration Is Inversely Associated with Insulin Resistance but Not Related with Metabolic Syndrome in Nondiabetic Korean Adults

Bang-In Ahn; Moon Jong Kim; Hyung Suk Koo; Namkyung Seo; Nam-Seok Joo; Young-Sang Kim

Although zinc was known to be associated with insulin metabolism and diabetes, the relationship of serum zinc concentration with insulin resistance (IR) and metabolic syndrome (MetS) was not well investigated in general population. The aim of this study is to evaluate the relationships of serum zinc concentration with IR and MetS in a nondiabetic adult population. This cross-sectional study included 656 men and 825 women who were nondiabetic adults from the fifth Korea National Health and Nutrition Examination Survey conducted in 2010. Serum zinc concentration and metabolic parameters were measured. IR was estimated by homeostatic model assessment (HOMA2). MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Serum zinc concentration was negatively correlated with homeostasis model assessment for insulin resistance (HOMA2-IR) in men (r = −0.104, P = 0.008), but not in women. After adjusting for conventional cardiovascular risk factors, the inverse correlation was significant in both men and women (B = −0.262, SE = 0.060 for men, and B = −0.129, SE = 0.052 for women). However, serum zinc concentration was not different between the groups with and without MetS (P = 0.752 for men and P = 0.371 for women). In conclusion, serum zinc concentration was inversely associated with IR but not related to MetS in nondiabetic adult population.


Korean Journal of Family Medicine | 2012

Effect of sunlight exposure on serum 25-hydroxyvitamin d concentration in women with vitamin d deficiency: using ambulatory lux meter and sunlight exposure questionnaire.

Sang-Hoon Lee; Soo-Jung Park; Kwang-Min Kim; Duck-Joo Lee; Woojae Kim; Rae Woong Park; Nam-Seok Joo

Background Vitamin D is an important factor in human health. Yet, vitamin D deficiency is very common. We aimed to confirm serum 25-hydroxyvitamin D (25OHD) concentration change after sunlight exposure and to elucidate the relationship between the amount of sunlight exposure and serum 25OHD level change by ambulatory lux meter and sunlight exposure questionnaire. Methods Twenty healthy young women were enrolled. They were educated to obtain 20 minutes of sunlight exposure during weekdays from October to November, 2010, during which they were to wear an ambulatory lux meter on an arm. All subjects completed a one-week recall sunlight exposure questionnaire at the end of the study. Before and after sunlight exposure, serum 25OHD level was measured. Results Mean pre-exposure serum 25OHD concentration was 11.01 ng/mL. The mean change of pre- and post-exposure 25OHD level was -0.62 ng/mL, but it was not statistically significant. The mean personal sunlight exposure recorded by ambulatory lux meter, 292.6 lux/s, showed no significant relationship with average change of 25OHD and average weekly sunlight exposure score, 11.9, calculated by the sunlight exposure questionnaire. However, the mean change of serum 25OHD level and weekly sunlight exposure score showed significant negative correlation (r = -0.469, P = 0.037). Conclusion Change of serum 25OHD concentration after four weeks of sunlight exposure was not statistically significant in women with vitamin D deficiency. However, serum 25OHD concentration change was significantly negatively correlated with the sunlight exposure score by the questionnaire.


Journal of Korean Medical Science | 2011

Women with Fibromyalgia Have Lower Levels of Calcium, Magnesium, Iron and Manganese in Hair Mineral Analysis

Young-Sang Kim; Kwang-Min Kim; Duck-Joo Lee; Bom-Taeck Kim; Sat-Byul Park; Doo-Yeoun Cho; Chang-Hee Suh; Hyoun-Ah Kim; Rae Woong Park; Nam-Seok Joo

Little is known about hair mineral status in fibromyalgia patients. This study evaluated the characteristics of hair minerals in female patients with fibromyalgia compared with a healthy reference group. Forty-four female patients diagnosed with fibromyalgia according to the American College of Rheumatology criteria were enrolled as the case group. Ageand body mass index-matched data were obtained from 122 control subjects enrolled during visit for a regular health check-up. Hair minerals were analyzed and compared between the two groups. The mean age was 43.7 yr. General characteristics were not different between the two groups. Fibromyalgia patients showed a significantly lower level of calcium (775 µg/g vs 1,093 µg/g), magnesium (52 µg/g vs 72 µg/g), iron (5.9 µg/g vs 7.1 µg/g), copper (28.3 µg/g vs 40.2 µg/g) and manganese (140 ng/g vs 190 ng/g). Calcium, magnesium, iron, and manganese were loaded in the same factor using factor analysis; the mean of this factor was significantly lower in fibromyalgia group in multivariate analysis with adjustment for potential confounders. In conclusion, the concentrations of calcium, magnesium, iron, and manganese in the hair of female patients with fibromyalgia are lower than of controls, even after adjustment of potential confounders.


Journal of Korean Medical Science | 2011

Vitamin K supplement along with vitamin D and calcium reduced serum concentration of undercarboxylated osteocalcin while increasing bone mineral density in Korean postmenopausal women over sixty-years-old.

Sang Hyeon Je; Nam-Seok Joo; Beomhee Choi; Kwang-Min Kim; Bom-Taeck Kim; Sat-Byul Park; Doo-Yeoun Cho; Kyu-Nam Kim; Duck-Joo Lee

There are inconsistent findings on the effects of vitamin K on bone mineral density (BMD) and undercarboxylated osteocalcin (UcOC). The present intervention study evaluated the effect in subjects over 60-yr-old. The vitamin K group (vitamin K + vitamin D + calcium supplement; 15 mg of vitamin K2 [menatetrenone] three times daily, 400 IU of vitamin D once a day, and 315 mg of calcium twice daily) and the control group (vitamin D + calcium supplement) were randomly assigned. During the six months of treatment, seventy eight women participated (38 in the vitamin K group and 40 in the control group) and 45 women completed the study. The baseline characteristics of study participants did not differ between the vitamin K and the control groups. In a per protocol analysis after 6 months, L3 bone mineral density has increased statistically significantly in the vitamin K group compared to the control group (0.01 ± 0.03 g/cm2 vs -0.008 ± 0.04 g/cm2, P = 0.049). UcOC concentration was also significantly decreased in the vitamin K group (-1.6 ± 1.6 ng/dL vs -0.4 ± 1.1 ng/dL, P = 0.008). In conclusion, addition of vitamin K to vitamin D and calcium supplements in the postmenopausal Korean women increase the L3 BMD and reduce the UcOC concentration.

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Chan-Won Kim

Sungkyunkwan University

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