Prenatal to peripubertal exposure to Di(2-ethylhexyl) phthalate induced endometrial atrophy and fibrosis in female mice.

Di(2-ethylhexy) phthalate (DEHP) is a widely used plasticizer that is ubiquitously found in the environment. Using a mouse model, we investigated the impact of early life DEHP exposure ranging from the prenatal to peripubertal developmental period of the female reproductive system. Pregnant female mice were allocated to three groups as follows: control, 100 mg/kg/day, and 500 mg/kg/day DEHP treatment. DEHP exposure was introduced through feeding during pregnancy (3 weeks) and lactation (3 weeks). After weaning, the offspring were also exposed to DEHP through feeding for another 2 weeks. Observations were conducted on female offspring at 10 and 24 weeks. The number of live offspring per dam was significantly lower in the high-DEHP-exposed group (500 mg/kg/day) compared to the control group (7.67 ± 1.24 vs. 14.17 ± 0.31; p < 0.05) despite no difference in pregnancy rates across the groups. Low-DEHP exposure (100 mg/kg/day) resulted to a decreased body weight (36.07 ± 3.78 vs. 50.11 ± 2.11 g; p < 0.05) and decreased left uterine length (10.60 ± 1.34 vs. 14.77 ± 0.82 mm; p < 0.05) in 24-week- old female mice. As early as 10 weeks, endometrial atrophy and fibrosis were observed, and endometrial cystic hyperplasia was noted in female mice at 24 weeks. Our study is the first to demonstrate that female mice exposed to DEHP in the early life developed endometrial fibrosis in the female offspring. Further studies on the consequences of these observations in fecundity and other reproductive functions are warranted.

Association between diet quality and type of meal companion: the 2013-2015 Korea National Health and Nutrition Examination Survey (KNHANES).

BACKGROUND/OBJECTIVES: A meal companion is an important social determinant of eating behaviors and is related to what and how much a person will eat within the social context. This study examined the difference in diet quality according to the type of dining companion. SUBJECTS/METHODS: This study included 15,074 adults (6,180 men and 8,894 women, ≥ 19 years) who participated in the 6th (2013-2015) Korea National Health and Nutrition Examination Survey. Korean Healthy Eating Index (KHEI) scores were calculated using the food frequency questionnaire data. Survey multivariate linear regression analysis was used to assess the association of dining companions (ordinary type, eating with family members, eating alone, and eating with others) and the total and component scores of KHEI. RESULTS: People who exclusively ate with someone other than family or exclusively ate alone had lower total KHEI scores in both men (57.23 ± 0.67, 58.56 ± 0.73 vs. 62.71 ± 0.26) and women (57.6 3±0.97, 63.89±0.58 vs. 65.79±0.22) compared to people with the ordinary type (all P < 0.05). Both men and women who ate exclusively with someone other than family had lower KHEI component scores for breakfast, whole grains, and fruit, excluding juice, compared to the ordinary type and family eating group. Compared to the eating alone group, the component scores for breakfast and whole grains were lower in the eating with others group. CONCLUSION: The diet quality differed according to the meal companion type. People who always ate with someone other than family members and men who ate alone showed lower diet quality scores than the ordinary type. More research will be needed to improve their adherence to dietary recommendations.

COVID-19 and related social distancing measures induce significant metabolic complications without prominent weight gain in Korean adults.

Background: This study using multi-center health examination data from Korean adults was conducted to confirm changes in weight, and their related cardiometabolic parameters, before and after strengthening of social distancing regulations. Methods: A retrospective cohort study was conducted using health check-up data from 13 university hospitals. The study period was from January 2018 to July 2020. To examine the effect of systematic social distancing measures, participants who underwent a health check-up (Visit 3) between July 2020 and July 2021 (during full scale social distancing), and had undergone two previous health check-ups (Visits 1 and 2) between January 2018 and June 2020 (before social distancing), were selected. In total, data from 7,875 participants were analyzed. Linear mixed-effect models were used to calculate estimates of anthropometric indices and metabolic markers measured on Visits 2 and 3, compared with measurements from Visit 1. Results: There were no significant differences in body weight, body mass index, waist circumference, and body composition on Visit 3 than on Visits 1 and 2. However, the odds of metabolic syndrome and its components, including hypertension, high glucose, diabetes, hypercholesterolemia, hypertriglyceridemia, hyper-non-high-density lipoprotein cholesterolemia, and dyslipidemia were significantly higher on Visit 3 than on Visits 1 and 2. The increase in metabolic complications was marked, particularly in relatively young adults who visited health check-up centers located in the capital area. Conclusion: Metabolic syndrome and its components were significantly worse after high level social distancing, although there were no significant increases in anthropometric indices and body fat levels. Healthcare providers need to prevent and manage worsening of metabolic parameters in subpopulations prone to be more sedentary and eat unhealthy food during the COVID-19 pandemic and associated social distancing measures.

Effect of MED-02 Containing Two Probiotic Strains, Limosilactobacillus fermentum MG4231 and MG4244, on Body Fat Reduction in Overweight or Obese Subjects: A Randomized, Multicenter, Double-Blind, Placebo-Controlled Study.

MED-02 is a complex supplement containing two probiotic strains, Limosilactobacillus fermentum MG4231 and MG4244, isolated from humans. The anti-obesity effects and safety profile of MED-02 were assessed in overweight and obese subjects. In this randomized, double-blinded, placebo-controlled, multicenter study, 100 healthy obese and overweight subjects aged 19-65 years with a body mass index (BMI) between 25 and 31.9 kg/m2 were recruited and randomized to receive a placebo or MED-02 (5 × 109 CFU/day). After 12 weeks of consumption, body fat mass (-1166.82 g vs. -382.08 g; p = 0.024) and body fat percentage (-0.85% vs. -0.11%; p = 0.030), as evaluated by dual-energy X-ray absorptiometry (DEXA) and body weight (-2.06 kg vs. -1.22 kg; p = 0.041), were significantly reduced in the MED-02 group compared to the placebo group. The safety profile did not differ among the groups. No serious adverse effects were observed in either group. These results suggest that MED-02 is a safe and beneficial probiotics that reduces body fat and body weight in overweight or obese individuals.

Fatty Liver Change in Korean Adults in a Systematic Social Distancing System Amid the COVID-19 Pandemic: A Multicenter Analysis.

In response to the COVID-19 pandemic, the Korean government implemented policies including the systematic social distancing (SSD) system which started on 28 June 2020. The present study investigated the development and aggravation of fatty liver measured using ultrasonography during the transition period (from pre-SSD to SSD) compared to the fatty liver changes during the pre-SSD period. Changes in fatty liver and liver enzymes were assessed in different groups stratified by alcohol consumption. Our retrospective cohort analysis included 5668 participants who underwent health checkups at 13 university hospitals during the SSD period and two or more checkups before the SSD period. Fatty liver developed and aggravated more in the transition period (13.6% development and 12.0% aggravation) than in the pre-SSD period (10.8% development and 10.1% aggravation) in the alcohol consumption group. This finding was more prominent in women than in men. Abnormal alanine transaminase levels were more often developed in the transition period than in the pre-SSD period, especially in men (11.1% vs. 8.6% in each period). In conclusion, the SSD system may contribute to fatty liver changes in individuals who regularly consume alcohol. Further research of the post-pandemic period is needed to assess long-term changes in fatty liver disease.

Relationship between psychological distress and the adherence to the Korean healthy eating index (KHEI): the Korea National Health and Nutrition Examination Survey (KNHANES) 2013 and 2015.

BACKGROUND/OBJECTIVES: This study examined the association of depressive symptoms, stress perception, and suicidal ideation with overall dietary quality using the newly developed Korean healthy eating index (KHEI). SUBJECTS/METHODS: This study included 9,607 adults (3,939 men and 5,668 women, ≥ 19 years) who participated in the 6th Korea National Health and Nutrition Examination Survey 2013 and 2015. The KHEI scores were calculated using the food frequency questionnaire data. Survey logistic regression analyses were performed to analyze the association between psychiatric distress and dietary quality. RESULTS: The percentage of subjects with experience of depressive mood, higher stress perception, and suicidal ideation was 8.2%, 25.0%, and 3.7% in men and 15.4%, 27.3%, and 6.0% in women, respectively. The mean KHEI score was 61.5 ± 0.29 in men and 64.8 ± 0.24 in women (P < 0.001). The present study found a difference in the adherence to specific dietary components of the KHEI between sexes. Men experiencing depressive symptoms were less likely to eat meat, fish, eggs, and beans, while depressed women showed lower vegetable intake. Both men and women with suicidal ideation showed a lower intake of vegetables. The men with stress had a lower breakfast eating score than those without stress (7.21 vs. 6.77, P = 0.016). The multivariate-adjusted odds ratios for depressive symptoms, stress perception, and the suicidal idea in women with the highest quartile of KHEI scores compared to the lowest quartile was 0.69 (95% confidence interval, 0.51-0.92), 0.73 (0.58-0.82), and 0.52 (0.33-0.82), respectively and significant dose-response associations were observed (P for trends < 0.05 for all). On the other hand, these associations were not observed in men after adjusting for the confounding variables (P for trends > 0.05 for all). CONCLUSIONS: Poor adherence to dietary recommendations is associated with psychological distress, especially in women.

Placental Transfer and Composition of Perfluoroalkyl Substances (PFASs): A Korean Birth Panel of Parent-Infant Triads.

Exposure to perfluoroalkyl substances (PFASs) is of public concern due to their persistent exposure and adverse health effects. Placental transfer of PFASs is an important excretion pathway of these chemicals in pregnant women and exposure route in fetuses. We measured PFAS concentrations in maternal, paternal, and umbilical cord serum collected from 62 pregnant Korean women and matched biological fathers of the fetuses. Placental transfer rates (cord to maternal serum ratio) of PFASs were also calculated. Demographics and pregnancy-related factors determining the placental transfer rates were identified using linear regression models. Maternal, paternal, and cord serum showed different PFASs compositions. Among the PFASs, perfluorooctane sulfonate (PFOS) showed the highest concentrations in maternal and paternal serum, while perfluorooctanoic acid (PFOA) showed the highest concentration in cord serum. There was a higher proportion of perfluoroalkyl carboxylic acids (PFCAs) with 9-12 carbon chains than those with 13-14 carbon chains in maternal and paternal serum, but this proportion was in the opposite direction in cord serum. PFOA and perfluorohexane sulfonate (PFHxS) had higher placental transfer rates (means of 0.32 and 0.36, respectively) than PFOS (mean of 0.12), which is in line with the results of previous studies. Gestational age and birth weight were positively associated with placental transfer rate of PFOA, PFHxS, and PFOS, while pre-pregnant BMI and weight were inversely associated with PFOS. This study showed that placental transfer of PFASs differs by compounds and is associated with pregnancy-related factors. Further studies on novel PFASs are warranted for Korean pregnant women.

Non-contact home-adapted device estimates sleep stages in middle-aged men: A preliminary study.

BACKGROUND: Sleep monitoring is essential to maintain a healthy life, especially for the elderly who want to age well. Among various forms of sleep devices, the non-wearable and home-adapted device might be preferred because it can be easily used. OBJECTIVE: In this study, we evaluated the performance of a non-contact home-adapted device compared to polysomnography (PSG), a gold standard method. METHODS: As a preliminary study, eight subjects were recorded over fourteen nights through PSG. The non-contact home-adapted device comprised a microwave sensor, passive infrared sensor, and smartphone application. Through the device, heart rate, respiratory rate, and body movement were collected and used to estimate sleep stages. Sleep structure was labeled in four classes: wake, REM, light, and deep sleep, and were classified using a weighted k-nearest neighbor algorithm. RESULTS: The device correctly estimated sleep structures with an overall epoch-by-epoch accuracy of 98.65% ± 0.05% based on leave-one-out cross-validation. The device showed significantly positive correlations with PSG in sleep indices including total sleep time, sleep efficiency, and wake after sleep onset. CONCLUSIONS: Our findings demonstrate a good performance of this non-contact and home-adapted device and suggest its suitability for sleep monitoring.

Circulating adipokines and risk of obesity related cancers: A systematic review and meta-analysis.

BACKGROUND: Obesity can influence on carcinogenesis through alterations in adipokines and subsequent inflammatory changes. This meta-analysis was aimed to comprehensively assess the association between circulating adipokines and risk of obesity-related cancers. METHODS: Pubmed and Embase were searched up to October 2017 for observational studies investigating the relationship between adipokines and cancers. Pooled odds ratio and the corresponding 95% confidence interval was estimated through the meta-analysis using a random-effects model. Findings A total of 93 observational studies (adiponectin = 60, high molecular weight adiponectin = 9, leptin = 39, IL-6 = 16, TNF-α = 10, and resistin = 17) were included. Adiponectin was significantly associated with decreased risk of cancer (pooled OR 0.70, 95% CI 0.60-0.80; I2 = 71.9%; Pheterogeneity <0.01). Leptin was significantly associated with increased risk of cancer (1.26, 1.05-1.51; I2 = 65.7%; Pheterogeneity <0.01). For each 5 µg/ml increase in adiponectin and 5 ng/ml increase in leptin, the pooled OR was 0.88 (0.83-0.93; I2 = 80.2%; Pheterogeneity <0.01) and 1.05 (1.01-1.09; I2 = 67.9%; Pheterogeneity<0.01)), respectively. There was nonlinear dose-response association (Pnonlinearity for adiponectin = 0.01; Pnonlinearity for leptin = 0.003).IL-6 (1.09, 0.94-1.25), TNF- α (1.65, 0.99-2.74), and resistin (1.28, 0.78-2.11) was not associated with risk of cancer. By cancer site and type, highest category of adiponectin was associated with decreased risk of breast (OR 0.74, 0.60-0.91), colorectal (0.74, 0.60-0.91), and endometrial cancer (0.49, 0.34-0.72). Higher leptin was associated with increased risk of endometrial (1.88, 1.24-2.87) and kidney cancer (2.07, 1.51-2.83). CONCLUSION: Our study suggests that adiponectin and leptin may play a role in the etiology of cancer.

Effects of central obesity on maternal complications in Korean women of reproductive age.

BACKGROUND: Considering the obesity-related complications in pregnancy and during delivery, prepregnancy central obesity may also affect pregnancy-related complications. This study aimed to assess the relationship between prepregnancy central obesity and adverse maternal outcomes in Korean women, by using the Korean National Health Insurance Service (NHIS) cohort. METHODS: In this population-based retrospective cohort study, we used data from the NHIS database, which contains information of health-care utilisation, diagnosis and prescription, and mortality for almost the whole Korean population, together with data from the NHIS health checkup database from 2005 to 2015. The NHIS health checkup data (645-280 days before childbirth) of mothers who had deliveries (total, 783,406 deliveries) from 2006 to 2015 were collected. For maternal adverse outcome data, we searched for diagnoses of maternal complications made during the period of 280 days before each delivery. The odds for maternal complications according to 8 body mass index (BMI) and 10 waist circumference (WC) categories were analysed using logistic regression. RESULTS: The incidence rates of eclampsia/preeclampsia, caesarean section, multiple gestation, and polycystic ovary syndrome (PCOS) increased according to the increase of BMI and WC. In contrast, the incidence rate of premature rupture of membrane (PROM) was inversely correlated with BMI and WC. In the low BMI (<17.5 and 17.5-19.9 kg/m2) and low WC (<60 and 60.0-64.0 cm) groups, the odds of threatened abortion were elevated. CONCLUSION: Prepregnancy WC was closely linked to some maternal complications, including eclampsia/preeclampsia, cesarean section, PCOS, and PROM, in a manner similar to prepregnancy BMI.

Distribution of fipronil in humans, and adverse health outcomes of in utero fipronil sulfone exposure in newborns.

Fipronil is a highly effective insecticide with extensive usages; however, its distribution and toxic/health effects in the human population after chronic exposure have not yet been clearly identified. Our objectives were to determine the levels of serum fipronil and fipronil sulfone, a primary fipronil metabolite, in a general and sensitive human population using a birth cohort of parent-infant triads in Korea. We further investigated whether in utero exposure to fipronil and fipronil sulfone can affect health outcomes in newborn infants. Blood and umbilical cord blood from 169 participants, 59 mother-neonate pairs and 51 matching biological fathers, were collected; serum fipronil and fipronil sulfone (both blood and cord blood) and serum thyroid hormones (cord blood) were measured. Demographic, physiological, behavioral, clinical, and socioeconomic data for each participant were collected via a one-on-one interview and a questionnaire survey. Fipronil sulfone was detected in the serum of mothers, fathers, and infantile cord blood, while fipronil itself was not. Maternal fipronil sulfone levels were correlated to those of matched biological fathers and newborn infants. Adjusted analyses identified significant associations between parental fipronil sulfone levels and household income. Infantile fipronil sulfone levels were significantly associated with both maternal and paternal levels as well as maternal pre-pregnant BMI. Furthermore, infantile fipronil sulfone levels were inversely associated with cord blood T3 and free T3 levels as well as 5-min Apgar scores of newborn infants. Serum fipronil sulfone was detected in a specific population of mother-neonate pairs and their matched biological fathers in a manner suggestive of regular exposure to fipronil among urban residents. The findings also suggest that serum fipronil sulfone placentally transfers to the fetus and affects infantile adverse health outcomes. This is a first of its kind study; therefore, future studies are warranted.

Effect of high-dose ginsenoside complex (UG0712) supplementation on physical performance of healthy adults during a 12-week supervised exercise program: A randomized placebo-controlled clinical trial.

BACKGROUND: Ginseng has been used as an ergogenic agent, although evidence for its effectiveness is weak. A randomized, double-blind, placebo-controlled clinical trial was conducted to evaluate the effect of a ginsenoside complex (UG0712) on changes in exercise performance. METHODS: Sedentary individuals (n = 117) were randomly assigned into one of three groups: low-dose ginsenoside supplementation (100 mg/d, n = 39), high-dose ginsenoside supplementation (500 mg/d, n = 39), or a placebo group (500 mg/d, n = 39). All participants underwent a supervised 12-wk aerobic and resistance exercise training course. To assess the effects of supplementation on physical performance, maximal oxygen consumption (VO2max), anaerobic threshold (AT), lactic acid, and muscle strength of the dominant knee were measured at baseline, every visit, and after the training program. RESULTS: Both ginsenoside groups showed significant increases in VO2max and muscular strength during exercise training. There were no definite changes in AT and lactic acid levels over time. After exercise training, there were definite differences in the VO2max (28.64.9 to 33.7 ± 4.9 ml/kg/min in high-dose group vs. 30.4 ± 6.7 to 32.8 ± 6.6 ml/kg/min in placebo, p = 0.029) and AT (19.3 ± 4.2 to 20.9 ± 3.5 ml/kg/min in high-dose group vs. 20.0 ± 5.1 to 20.0 ± 4.9 ml/kg/min in placebo, p = 0.038) between the high-dose ginsenoside and placebo groups. However, there was no difference in VO2max between the low-dose ginsenoside and placebo groups (p = 0.254). There were no differences in muscular strength during exercise training among the three groups. CONCLUSION: High-dose ginsenoside supplementation (UG0712) augmented the improvement of aerobic capacity by exercise training.

Eating alone and metabolic syndrome: A population-based Korean National Health and Nutrition Examination Survey 2013-2014.

Eating alone has been an emerging social concern in modern life. However, there is little research on the association between eating alone and Metabolic syndrome (MetS). We aimed to assess the association between eating alone and the MetS and to identify whether sociodemographic factors modify this association. This study included 7725 adults (≥19 years) who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) 2013-2014. Multivariable logistic regression analysis was used for assessing the association of eating alone (none, 1 time/day, and ≥2 times/day) with MetS. The percentages of subjects with MetS were 30.4% in men and 24.2% in women. 20.8% of men and 29.2% of women ate alone ≥2 times/day. Individuals who ate alone 2 or more times per day showed higher frequency of living alone, having no spouse, skip meals, and less eating out (p<0.05). Women with eating alone ≥2 times/day had a crude OR of 1.29 (95% CI:1.08-1.53, p-trend=0.001) for MetS compared with women without eating alone. However, this association was no longer significant after adjustments for confounding factors. Eating alone ≥2 times/day was significantly associated with increase abdominal obesity (OR, 95% CI:1.45, 1.10-1.91, p-trend=0.039) and MetS (1.64, 1.28-2.10, p-trend=0.004) in men. Eating alone was associated with a higher likelihood of having a MetS in men without spouse as compared with those with spouse (OR for men without spouse 3.02, 95% CI:1.50-6.11 and OR for men with spouse 1.48, 95% CI:1.22-1.7, p-interaction=0.027). Our results indicate that eating alone may be a potential risk factor for MetS.

Recent Shift of Body Mass Index Distribution in Korea: a Population-based Korea National Health Insurance Database, 2002-2013.

We investigated trends of obesity prevalence among adult Koreans. Data from 110,280,952 participants who underwent medical examination provided by the National Health Insurance System from 2002-2013 were analyzed. The prevalence of moderate obesity (body mass index [BMI] 25.0-29.9 kg/m²) was slightly increased from 2002 (30.7%) through 2010 (33.1%) and reached a plateau since 2010 among men but continuously decreased from 22.5% in 2002 to 20.9% in 2013 among women. However, severe obesity (BMI ≥ 30.0 kg/m²) was rapidly increased and the prevalence in 2013 (4.2%) was almost doubled the prevalence in 2002 (2.5%). We observed a steep rise of severe obesity as well as potentially right shifting of the obese category.

Vitamin B2 intake and colorectal cancer risk; results from the Nurses' Health Study and the Health Professionals Follow-Up Study cohort.

Vitamin B2 serves as a cofactor to enhance one-carbon metabolism, maintain mucous membranes, and has been implicated in lowering colorectal cancer (CRC) risk. However, few prospective studies have examined the association between vitamin B2 intake and CRC. In this study, we estimated the associations between vitamin B2 intake and CRC risk using the Nurses' Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS) cohorts. Vitamin B2 intake was measured by a validated food frequency questionnaire every 4 years. Among 100,033 women in the NHS and 44,007 men in the HPFS we documented a total of 3,037 incident CRC cases (2,093 women and 944 men) during 24-26 years of follow-up until 2010. Intakes of total (from food and supplements), dietary (from food only), and supplemental vitamin B2 were inversely related to CRC risk in age-adjusted analysis in NHS. However, the association was attenuated and no longer statistically significant in multivariate analysis (p-trend ≥0.08). The pooled multivariate relative risks (95% confidence interval) comparing individuals in the extreme quintiles of intakes were 0.93 (0.81-1.06) for total vitamin B2, 0.89 (0.61-1.28) for dietary vitamin B2 and 0.94 (0.81-1.08) for supplemental vitamin B2. These associations of total vitamin B2 intake were similar for risk of CRC with varying lag-time periods (0-4, 4-8, 8-12 or 12-16 years), for risk of CRC subtypes by tumor location, and across strata of intake of folate or alcohol. Our prospective data do not support a beneficial role of vitamin B2 intake in lowering incidence of CRC.

Differences in the associations of anthropometric measures with insulin resistance and type 2 diabetes mellitus between Korean and US populations: Comparisons of representative nationwide sample data.

BACKGROUNDS: Variation among ethnic groups in the association between obesity and insulin resistance (IR)/diabetes has been suggested, but studies reported inconsistent results. We evaluated ethnic differences in the association between obesity and insulin resistance (IR)/diabetes. METHODS: We conducted a cross-sectional analysis using Korea (n=18,845) and the USA (n=4657) National Health and Nutrition Examination Survey(NHANES) 2007-2010. We performed statistical comparisons of AUC-ROC (area under the curve in a receiver operating characteristic curve) values for body mass index (BMI), waist circumference (WC) and homeostasis model assessment of insulin resistance (HOMA-IR) to predict IR or diabetes among different ethnic groups. RESULTS: AUC-ROC values for BMI and WC for predicting IR were highest in Whites (0.8324 and 0.8468) and lowest in Koreans (0.7422 and 0.7367). Whites showed the highest AUC-ROC values for BMI (0.6869) and WC (0.7421) for predicting diabetes, while the AUC-ROC for HOMA-IR was highest in Koreans (0.8861). Linear regression showed significant interactions between ethnicity and the main effects (all P<0.0001). Increases in BMI were associated with a larger increase in HOMA-IR in Whites (ß=0.0719) and WC in Hispanics (ß=0.0324), while BMI was associated with a larger increase in fasting glucose in Koreans (ß=0.8279) and WC in Blacks (ß=0.4037). In addition, the slope for fasting glucose with increasing HOMA-IR was steeper in Koreans (ß=16.5952, P<0.001) than in other groups. CONCLUSION: The ability of BMI and WC to predict IR and diabetes was highest in Whites, while the ability of HOMA-IR to predict diabetes was highest in Koreans.

Development of the Perceived Stress Inventory: A New Questionnaire for Korean Population Surveys.

BACKGROUND: Given emerging evidence of the association between stress and disease, practitioners need a tool for measuring stress. Several instruments exist to measure perceived stress; however, none of them are applicable for population surveys because stress conceptualization can differ by population. The aim of this study was to develop and validate the Perceived Stress Inventory (PSI) and its short version for use in population surveys and clinical practice in Korea. METHODS: From a pool of perceived stress items collected from three widely used instruments, 20 items were selected for the new measurement tool. Nine of these items were selected for the short version. We evaluated the validity of the items using exploratory factor analysis of the preliminary data. To evaluate the convergent validity of the PSI, 387 healthy people were recruited and stratified on the basis of age and sex. Confirmatory analyses and examination of structural stability were also carried out. To evaluate discriminatory validity, the PSI score of a group with depressive symptoms was compared with that of a healthy group. A similar comparison was also done for persons with anxious mood. RESULTS: Exploratory factor analysis supported a three-factor construct (tension, depression, and anger) for the PSI. Reliability values were satisfactory, ranging from 0.67 to 0.87. Convergent validity was confirmed through correlation with the Perceived Stress Scale, Center for Epidemiologic Studies Depression Scale, and State-Trait Anxiety Inventory. People with depressive or anxious mood had higher scores than the healthy group on the total PSI, all three dimensions, and the short version. CONCLUSION: The long and short versions of the PSI are valid and reliable tools for measuring perceived stress. These instruments offer benefits for stress research using population-based surveys.

Circulating levels of IGF-1, IGFBP-3, and IGF-1/IGFBP-3 molar ratio and colorectal adenomas: A meta-analysis.

BACKGROUNDS: Insulin-like growth factor-1(IGF-1) promotes cell proliferation and inhibits apoptosis, and is thereby implicated in carcinogenesis. Insulin-like growth factor binding protein-3 (IGFBP-3) may antagonize IGF-1 action, leading to inhibition of the potential tumorigenicity of IGF-1. We conducted this meta-analysis to estimate the association between IGF-1, IGFBP-3 and IGF-1/IGFBP-3 ratio and the risk of colorectal adenomas (CRAs). Further, we investigated whether this association was different between occurrent and recurrent CRA, by adjustment for obesity, and by advanced CRA. MATERIALS AND METHODS: Pubmed and Embase were searched up to April, 2015 to identify relevant observational studies and summary odds ratio (OR) and the corresponding 95% confidence interval (95% CI) was estimated using a random-effects model. RESULTS: A total of 12 studies (11 studies including 3038 cases for IGF-1, 12 studies including 3208 cases for IGFBP-3, and 7 studies including 1867 cases for IGF-1/IGFBP-3 ratio) were included in this meta-analysis. The summary ORs of occurrent CRA for the highest versus lowest category of IGF-1, IGFBP-3 and IGF-1/IGFBP-3 ratio were 1.13 (95% CI: 0.95-1.34), 0.99 (0.84-1.16), and 1.05 (0.86-1.29), respectively. Higher IGF-1 and IGF-1/IGFBP-3 ratio were significantly associated with decreased risk of recurrent CRA (OR for IGF-1=0.60 [95% CI: 0.42-0.85]; IGF-1/IGFBP-3 ratio=0.65 [0.44-0.96]). A stratified analysis by advancement of occurrent CRA produced a significant summary OR of IGF-1 for advanced CRA (OR=2.21 [1.08-4.52]) but not for non-advanced CRA (OR=0.89 [0.55-1.45]). We did not find significant publication bias or heterogeneity. CONCLUSION: Circulating levels of IGF-1, IGFBP-3 and their molar ratio were not associated with the risk of occurrence of CRA, but IGF-1 was associated with the increased risk for occurrence of advanced CRA.

Hyperinsulinemia, insulin resistance and colorectal adenomas: A meta-analysis.

BACKGROUND: Insulin stimulates cell proliferation and inhibits apoptosis. While epidemiologic studies have investigated associations between markers of insulin resistance/hyperinsulinemia (i.e., circulating insulin, homeostasis model assessment-insulin resistance (HOMA-IR), C-peptide) and risk of colorectal adenoma (CRA), the effect size has not yet been quantified. OBJECTIVE: We aimed to summarize the association between hyperinsulinemia/insulin resistance and risk of CRA, including whether the association is independent of adiposity. MATERIALS AND METHODS: Pubmed and Embase were searched through April, 2015 to identify observational studies investigating the associations between insulin, C-peptide and HOMA-IR and CRA risk. Using the highest versus lowest category meta-analysis and dose-response meta-analysis based on a random-effects model, we estimated summary odds ratio (OR) and the corresponding 95% confidence interval (95% CI). RESULTS: A total of 27 studies (insulin: 16 studies including 14,007 cases; C-peptide: 11 studies including 8639 cases; HOMA-IR: 8 studies including 11,619 cases) were included in this meta-analysis. The summary ORs of CRA comparing the highest with the lowest quantile were 1.33 for insulin (95% CI=1.12-1.58, I(2)=73.9%, Pheterogeneity<0.001), 1.44 for C-peptide (95% CI=1.13-1.83, I(2)=63.5%, Pheterogeneity=0.003), and 1.33 for HOMA-IR (95% CI=1.10-1.60, I(2)=69.1%, Pheterogeneity=0.004). Upon stratification by ethnicity, higher levels of insulin and C-peptide were significantly associated with increased risk of CRA in non-Asian ethnicity (summary OR for insulin=1.67 [95% CI=1.28-2.17], I(2)=34.9%, Pheterogeneity=0.16; summary OR for C-peptide=1.59 [95% CI=1.22-2.08], I(2)=21.5%, Pheterogeneity=0.27) but not in Asians (summary OR for insulin=1.10 [95% CI=0.92-1.33], I(2)=76.6%, Pheterogeneity=0.001; summary OR for C-peptide=1.27 [95% CI=0.84-1.91], I(2)=72.6, Pheterogeneity=0.01). We observed evidence for the existence of publication bias for insulin (P=0.01 by Egger test) and HOMA-IR (P=0.05 by Egger test). The results were confirmed in linear dose-response meta-analysis. These significant positive associations generally persisted even after adjustment for adiposity, although the effect size was substantially attenuated. CONCLUSIONS: Independent of adiposity, higher levels of insulin, C-peptide, and HOMA-IR were significantly associated with increased risk of CRA. The weaker associations and high heterogeneity in Asian studies warrant further research. These results indicate that insulin resistance and hyperinsulinemia may contribute in part to the association between obesity and CRA risk.

Measurement of antioxidant capacity using the biological antioxidant potential test and its role as a predictive marker of metabolic syndrome.

BACKGROUND/AIMS: Oxidative stress increases the risk of cardiovascular complications of metabolic syndrome (MetS). This study was conducted to examine the difference in antioxidant capacity according to the presence of MetS, and to characterize the association between antioxidant capacity and MetS-related factors. METHODS: We used the biological antioxidant potential (BAP) test to estimate antioxidant capacity. The BAP test has recently been used as an indicator of antioxidant capacity. We measured BAP levels in 45 patients with MetS (mean age, 44.6 ± 1.1 years) and 47 age- and sex-matched controls (mean age, 42.7 ± 1.1 years). To evaluate the association between antioxidant capacity and MetS, adiponectin, high-sensitivity C-reactive protein (hs-CRP), interleukin-6, tumor necrosis factor-α, and homeostatic model assessment for insulin resistance (HOMA-IR), linear regression and logistic analyses were performed. RESULTS: The mean BAP of the MetS group (1,937.3 ± 36.5 µmol/L) was significantly lower than that of the non-MetS group (2,101.7 ± 29.5 µmol/L). Also, the mean BAP was low in persons having low high density lipoprotein and high triglyceride. Reduced antioxidant capacity was significantly associated with adiponectin, HOMA-IR and hs-CRP after adjusting for age and sex. The odds ratios for MetS with BAP, log adiponectin, log HOMA-IR, and log hs-CRP were 0.63 (95% confidence interval [CI], 0.49 to 0.82), 0.22 (0.10 to 0.51), 14.24 (4.35 to 46.58), and 1.93 (1.36 to 2.75), respectively. CONCLUSIONS: Persons with MetS showed reduced antioxidant capacity. We identified relationships between antioxidant capacity measured by BAP test and MetS, as well as MetS-related factors, such as insulin resistance, hs-CRP, and adiponectin.