Lead, Mercury, and Cadmium Exposure in the Korean General Population.

BACKGROUND: Lead (Pb), mercury (Hg), and cadmium (Cd) are well-known environmental pollutants. They are unnecessary in the biological processes of humans. This study was performed to estimate the representative background exposure levels to the metals by measuring concentrations in whole blood of the Korean general population. METHODS: This population-based cross-sectional study included 4,000 subjects (1,886 males and 2,114 females) 0-83 years of age in 2010 and 2011. Adult subjects (≥ 19 years of age) were collected by sex- and age-stratified probability method, and preschool- and school-aged subjects were recruited by a cluster sampling method. Written consent was provided prior to blood sampling. Pb and Cd blood concentrations were determined by a flameless atomic absorption spectrophotometry, and blood Hg was analyzed by a direct Hg analyzer. RESULTS: The geometric mean, median and 95th percentile of blood Pb was 1.82 µg/dL, 1.83 µg/dL, and 3.78 µg/dL, respectively. The respective values were 2.92 µg/L, 2.87 µg/L, 9.12 µg/L for Hg, and 0.56 µg/L, 0.59 µg/L, 2.20 µg/L for Cd. Blood Pb and Hg were higher in males than in females, but no sex difference was observed, respectively, in subjects 0-4 years of age for Pb and in subjects less than 20 years for Hg. However, blood Cd was higher in females than in males and no sex difference was observed in subjects < 30 years of age. CONCLUSION: This study provides representative data of human exposure to Pb, Hg, and Cd covering whole age groups of the general population in Korea.

Lead, Mercury, and Cadmium Exposure in the Korean General Population

BACKGROUND: Lead (Pb), mercury (Hg), and cadmium (Cd) are well-known environmental pollutants. They are unnecessary in the biological processes of humans. This study was performed to estimate the representative background exposure levels to the metals by measuring concentrations in whole blood of the Korean general population. METHODS: This population-based cross-sectional study included 4,000 subjects (1,886 males and 2,114 females) 0–83 years of age in 2010 and 2011. Adult subjects (≥ 19 years of age) were collected by sex- and age-stratified probability method, and preschool- and school-aged subjects were recruited by a cluster sampling method. Written consent was provided prior to blood sampling. Pb and Cd blood concentrations were determined by a flameless atomic absorption spectrophotometry, and blood Hg was analyzed by a direct Hg analyzer. RESULTS: The geometric mean, median and 95th percentile of blood Pb was 1.82 µg/dL, 1.83 µg/dL, and 3.78 µg/dL, respectively. The respective values were 2.92 µg/L, 2.87 µg/L, 9.12 µg/L for Hg, and 0.56 µg/L, 0.59 µg/L, 2.20 µg/L for Cd. Blood Pb and Hg were higher in males than in females, but no sex difference was observed, respectively, in subjects 0–4 years of age for Pb and in subjects less than 20 years for Hg. However, blood Cd was higher in females than in males and no sex difference was observed in subjects < 30 years of age. CONCLUSION: This study provides representative data of human exposure to Pb, Hg, and Cd covering whole age groups of the general population in Korea.

Relative contribution of obesity and serum adiponectin to the development of hypertension.

AIMS: The aim of this study was to investigate the association between serum adiponectin level and new-onset hypertension, and the relative contribution of obesity and low serum adiponectin levels to the development of hypertension in normotensive men and women. METHODS: We analyzed 1553 adults (584 men and 969 women) without hypertension, aged 40-70 years, who had participated in a cohort study in both time periods from 2005 to 2008 for baseline and 2008 to 2011 for follow-up. We divided participants into sex-specific tertiles according to serum adiponectin levels. We defined the highest tertile of serum adiponectin as 'high adiponectin'. Participants were then stratified into four groups: the non-obese with high adiponectin; the non-obese with low adiponectin; the obese with high adiponectin; and the obese with low adiponectin. RESULTS: During an average of 2.6 years of follow-up, 79 men (13.5%) and 99 women (10.2%) developed hypertension. Low serum adiponectin level was an independent predictor of new-onset hypertension in men (Odds Ratio[OR]: 1.99; 95% CI: 1.03-3.86). The Obese men with low adiponectin had an increased risk of new-onset hypertension compared with the control group (OR: 2.80; 95% CI: 1.35-5.81). In postmenopausal women, the obese subjects with low adiponectin had an increased risk of new-onset hypertension compared with the control group (OR: 2.41; 95% CI 1.16-5.04). CONCLUSION: Low serum adiponectin levels were associated with an increased risk of new-onset hypertension in men and postmenopausal women.

Positive-Thinking and Life Satisfaction amongst Koreans

PURPOSE: The present study examined the positive-thinking and life satisfaction of the general Korean population. In particular, we examined the role of positive-thinking on participants' life satisfaction. MATERIALS AND METHODS: We conducted a telephone survey of 409 respondents (194 males, 215 females). The participants provided self-reports on their positive thinking, life satisfaction and demographic information. ReESULTS: The results showed that age, education, occupation, and family income had an influence on positive- thinking as well as life satisfaction in Korea. Specifically, younger respondents and persons with high incomes or higher education degrees were more likely to have higher positive scores and thus higher life satisfaction scores. However, after controlling for the demographic variables, positive thinking significantly affected life satisfaction(R(2) Change=0.170, F= 88.56, p < 0.001). CONCLUSION: We provided empirical evidence that positive thinking may indeed play a significant role in life satisfaction. Therefore, positive thinking would offer important direction for the growth of life satisfaction and interventions aiming to remediate the effects of demographic variables on life satisfaction.

Positive-Thinking and Life Satisfaction amongst Koreans

PURPOSE: The present study examined the positive-thinking and life satisfaction of the general Korean population. In particular, we examined the role of positive-thinking on participants' life satisfaction. MATERIALS AND METHODS: We conducted a telephone survey of 409 respondents (194 males, 215 females). The participants provided self-reports on their positive thinking, life satisfaction and demographic information. ReESULTS: The results showed that age, education, occupation, and family income had an influence on positive- thinking as well as life satisfaction in Korea. Specifically, younger respondents and persons with high incomes or higher education degrees were more likely to have higher positive scores and thus higher life satisfaction scores. However, after controlling for the demographic variables, positive thinking significantly affected life satisfaction(R(2) Change=0.170, F= 88.56, p < 0.001). CONCLUSION: We provided empirical evidence that positive thinking may indeed play a significant role in life satisfaction. Therefore, positive thinking would offer important direction for the growth of life satisfaction and interventions aiming to remediate the effects of demographic variables on life satisfaction.

The Relationship among Eating Traits, Personality Characteristics, and Other Psychopathology in the Korean General Population / 신경정신의학

OBJECTIVE: The purposes of this study were to clarify the roles of personality characteristics and general psychopathology, including depression and hypochondriasis, in individuals with eating disorders, and to test a continuum hypothesis of eating disorders. METHODS: Using a multi-stage questionnaire sampling method including area sampling, proportionated stratified sampling, and quota sampling, we surveyed 3,062 subjects(1249 males and 1813 females) from a target of 4,400 Korean adults over the age of 18 in a nationwide area(9 ku's, 10 middle or small cities, and 17 kun's). We used the questionnaire which consisted of three parts:general information, scales for eating traits, and scales for personality characteristics and other general psychopathology. RESULTS: Psychoticism was the only personality characteristics which had a significant relationship with various eating traits including 'eating habits'(r=-0.3195), 'the Eating Attitudes Test'(EAT, r=0.3657), and 'preference for vegetables and fish, and dislike for sweet,tasting foods'(r=-0.2740). Lie scale also had a significant relationship with 'preference for snacks and instant foods'(r=-0.2117). These results were consistent in examining the relationships across genders. In female, there was a significant relationship between 'preference for the traditional Korean foods' and 'psychoticism'(r=-0.2103) in addtion to above relationships. However, there were no significant relationships between any of the eating traits and other psychopathology. Relative to the relationship between personality characteristics and general psychopathology, there were significant correlations between 'depression' and 'interoversion-extraversion'(r=-0.2174), 'depression' and 'neuroticism'(r=0.4510>, and 'hypochondriasis' and 'neuroticism'(r=0.3432). These correlations in female was the same as those of the total group, while among males, 'depression' was significantly correlated with all four personality characteristics, and 'hypochondriasis' was significantly correlated with 'interoversion-extraversion'(r=-0.2265) and 'neuroticism'(r=0.3762). CONCLUSION: These results suggest that psychoticism is the only personaltiy characteristics related to eating-specific psychopathology, while general psychopathology, such as depression and hypochondriasis is not related to eating pathology but may influence eating disorders by their interaction with other personality characteristics, such as interoversion-extraversion and neuroticism. Considering the results of previous studies in the patients with eating disorders and high risk groups, which are similar with our results in the general population, our results support a continuum hypothesis of eating disorders. Our results also suggest that gender differences in the pathology of eating disorders are the result not of difference in eating-specific pathology itself but through difference in influences of concurrent general psychopathology, such as depression and hypochondriasis.