Sex difference in skeletal muscle mass in relation to metabolic dysfunction-associated steatotic liver disease: a propensity score matching study.

BACKGROUND: While low muscle mass is considered a risk factor for metabolic dysfunction-associated steatotic liver disease (MASLD), whether the relationship is independent of fat mass remains unclear. OBJECTIVES: This study aims to clarify the association between the sex-specific height-adjusted low skeletal muscle mass index (LSMI) and MASLD. METHODS: Data from the 2008-2010 Korean National Health and Nutrition Examination Survey were analyzed. LSMI was defined using the 2019 Asian Working Group for Sarcopenia. The non-alcoholic fatty liver disease-liver fat score was used to assess MASLD. Gender-specific 1:1 propensity score matching (PSM) was performed to mitigate the confounding effects of anthropometric variables and lifestyles. Conditional logistic analysis was used on the dataset after PSM to estimate the odds ratio (OR) with a 95% confidence interval (CI). RESULTS: After PSM, the prevalence of MASLD was significantly higher in men with LSMI than in those without LSMI (37.4% vs. 29.6%). No significant difference was observed in the prevalence of MASLD between groups after PSM in women (20.4% vs. 20.3%). Conditional logistic analysis revealed that the odds of having MASLD were significantly higher in men with LSMI compared to those without LSMI (OR = 1.38, 95% CI: 1.09-1.75), while no significant association was found in women with LSMI (OR = 1.10, 95% CI: 0.87-1.40). CONCLUSION: Height-adjusted LSMI is an independent factor associated with MASLD in the condition of the same level of fat mass in men. Further prospective studies in diverse populations are needed to confirm our findings.

Bioelectrical impedance parameters add incremental value to waist-to-hip ratio for prediction of metabolic dysfunction associated steatotic liver disease in youth with overweight and obesity.

Introduction: Metabolic dysfunction-associated steatotic liver disease (MASLD) presents a growing health concern in pediatric populations due to its association with obesity and metabolic syndrome. Bioelectrical impedance analysis (BIA) offers a non-invasive and potentially effective alternative for identifying MASLD risk in youth with overweight or obesity. Therefore, this study aimed to assess the utility of BIA for screening for MASLD in the youth. Method: This retrospective, cross-sectional study included 206 children and adolescents aged <20 years who were overweight and obese. The correlations between anthropometric measurements and BIA parameters and alanine aminotransferase (ALT) levels were assessed using Pearson's correlation analysis. Logistic regression analysis was performed to examine the associations between these parameters and ALT level elevation and MASLD score. Receiver operating characteristic (ROC) curves were generated to assess the predictive ability of the parameters for MASLD. Results: Pearson's correlation analysis revealed that waist-to-hip ratio (WHR), percentage body fat (PBF), and BIA parameters combined with anthropometric measurements were correlated with ALT level. Logistic regression revealed that WHR, skeletal muscle mass/WHR, PBF-WHR, fat-free mass/WHR, and appendicular skeletal muscle mass/WHR were correlated with ALT level elevation after adjusting for age, sex, and puberty. WHR, PBF-WHR, and visceral fat area (VFA)-WHR were positively correlated with the MASLD score in the total population after adjusting for age, sex, and puberty. PBF-WHR and VFA-WHR were correlated with the MASLD score even in youth with a normal ALT level. The cutoff points and area under the ROC curves were 34.6 and 0.69 for PBF-WHR, respectively, and 86.6 and 0.79 for VFA-WHR, respectively. Discussion: This study highlights the utility of combining BIA parameters and WHR in identifying the risk of MASLD in overweight and obese youth, even in those with a normal ALT level. BIA-based screening offers a less burdensome and more efficient alternative to conventional MASLD screening methods, facilitating early detection and intervention in youth at risk of MASLD.

Interplay of Mediterranean-diet adherence, genetic factors, and metabolic dysfunction-associated steatotic liver disease risk in Korea.

BACKGROUNDS: Metabolic dysfunction-associated steatotic liver disease (MASLD) has gained attention owing to its severe complications. This study aimed to explore the interaction between Mediterranean-diet (MD) adherence, genetic factors, and MASLD risk in a Korean population. METHODS: In total, 33,133 individuals aged 40 years and older from the Korean Genome and Epidemiology Study (KoGES) were analyzed. Participants were assessed for MASLD based on criteria and MD adherence measured by the Korean version of the Mediterranean-Diet Adherence Screener (K-MEDAS). Individuals were categorized into two groups based on their MD adherence: high adherence (K-MEDAS > 6) and low adherence (K-MEDAS < 5). Single nucleotide polymorphism (SNP) genotypes were obtained using the Korea Biobank array. Logistic regression was used to examine the single-marker variants for genetic associations with MASLD prevalence. RESULTS: Individuals were categorized into MASLD (10,018 [30.2%]) and non-MASLD (23,115 [69.8%]) groups. A significant interaction was observed between the rs780094 glucokinase regulatory protein (GCKR) gene and K-MEDAS on MASLD (p < 10 - 2 ). Of individuals with K-MEDAS > 6, those carrying the minor allele (C) of the GCKR gene rs780094 exhibited a lower risk of MASLD compared to those without the allele (odds ratio [OR] = 0.88 [0.85-0.91], p-value = 5.54e-13). CONCLUSION: The study identified a significant interaction involving the rs780094 variant near the GCKR gene, with carriers of the minor allele exhibiting a lower MASLD risk among those adhering well to the MD. Dietary habits influence the MASLD risk associated with the rs780094 allele, emphasizing the need for personalized nutrition recommendations.

Assessing blood sugar measures for predicting new-onset diabetes and cardiovascular disease in community-dwelling adults.

PURPOSE: Diabetes mellitus (DM) is a global health concern linked to various complications, including cardiovascular disease (CVD). However, long-term follow-up studies on the risk of DM and CVD using different blood glucose assessment methods in the general Korean population are lacking. This study aimed to assess the predictive abilities of fasting plasma glucose (FPG), 2-h oral glucose tolerance test (OGTT), and glycosylated hemoglobin (HbA1c) for new-onset DM and high CVD risk in a middle-aged and older Korean population. METHODS: This study used data from the Korean Genome and Epidemiology Study, a population-based prospective cohort. Blood sugar measures (FPG, OGTT, and HbA1c) were examined. The primary endpoint was the development of new-onset DM, and CVD risk was evaluated using the Framingham risk score. The predictive abilities for new-onset DM based on glycemic values were evaluated using Harrell's Concordance index and 95% confidence intervals. RESULTS: Among the 10,030 participants, data of 6813 participants without DM at baseline were analyzed. The study revealed that OGTT outperformed FPG and HbA1c in predicting new-onset DM. The combination of FPG and HbA1c did not significantly enhance predictions for DM compared with OGTT alone. OGTT also outperformed FPG and HbA1c in predicting high CVD risk, and this difference remained significant even after adjusting for additional confounders. CONCLUSION: OGTT has superior predictive capabilities in identifying new-onset DM and high CVD risk in the Korean population. This suggests that relying solely on individual blood sugar measures may be insufficient for assessing DM and CVD risks.

Age at menopause and risk of metabolic dysfunction-associated fatty liver disease: A 14-year cohort study.

BACKGROUNDS & AIMS: Menopause, characterized by a sudden decline in estrogen levels, has significant effects on women's health, especially when it occurs early. This study aimed to investigate the associations between menopausal age and incidence of metabolic dysfunction-associated fatty liver disease (MAFLD) using a large cohort and a long-term follow-up. METHODS: Menopausal age was categorized into four groups (G1-4 [<40, 40-44, 45-49, and ≥50 years, respectively]). Cox proportional hazards regression analysis was used to assess the risk of developing MAFLD during the follow-up period according to the menopausal age categories. RESULTS: A total of 1,888 participants were included in the final analysis and followed for a median period of 12.3 years. The unadjusted hazard ratios (95 % CIs) for the incidence of new-onset MAFLD were 1.11 (0.93-1.32), 1.15 (0.90-1.47), and 1.52 (1.12-2.07) in G3, G2, and G1, respectively, compared with that in G4. After adjusting for confounders, the hazard ratio (95 % CIs) for the incidence of new-onset MAFLD was 1.40 (1.00-1.95) in G1 compared with that in G4. CONCLUSION: The risk of developing MAFLD was higher in women with premature menopause (<40 years) than in those with menopause aged ≥50 years.

Association between Consumption of Iodine-Rich Foods and Thyroid Cancer Prevalence: Findings from a Large Population-Based Study.

The influence of iodine-rich foods on thyroid cancer (TC) risk remains inadequately understood. Therefore, we aimed to comprehensively investigate the relationship between three iodine-rich food groups and TC prevalence using extensive data from a large Korean population. We assessed the dietary intake of 169,057 participants in the Korean Genome and Epidemiology Study (2004-2013) using a food frequency questionnaire. The top-three iodine-rich food groups (including egg, seaweed, and dairy) were selected based on Korean dietary reference intakes and categorized by weekly consumption frequency. We conducted multiple logistic regression models to examine the relationship between food consumption and TC prevalence. After adjusting for confounding factors, higher seaweed consumption (>5 times/week) was significantly associated with lower TC prevalence (odds ratio [OR], 95% confidence interval [CI] = 0.42, 0.32-0.56, p-value < 0.001). In contrast, compared with moderate dairy consumption (3-4 times/week), lower dairy product intake (<1 time/week) was associated with higher TC prevalence (OR, 95% CI = 1.32, 1.05-1.67, p-value = 0.017). Our findings suggest that sufficient seaweed consumption may offer protection against TC, and incorporating dairy products into the diet may lower TC incidence in the Korean population. The most significant limitations of our study are the absence of 24 h urine samples for iodine status assessment and the lack of clinical data on the diagnosis of thyroid cancer.

Difference in association of carbohydrate intake with all-cause mortality between middle-aged and older Korean adults with and without diabetes mellitus: A prospective study.

BACKGROUND & AIMS: The relationship between diet and health, particularly the role of carbohydrates, has been extensively studied. However, carbohydrate intake based on individual health conditions remains unclear. Here, we aimed to investigate whether the association between carbohydrate intake and all-cause mortality varied between individuals with and without diabetes mellitus (DM). METHODS: This prospective cohort study used data from the Korean Genome and Epidemiology Study (KoGES). Overall, 143,050 participants were included, with 10.1% having DM. Dietary intake was assessed using a semiquantitative food frequency questionnaire. Cox proportional hazards regression models were used to assess the association between carbohydrate intake and mortality after adjusting for confounders. RESULTS: The study showed that 5436 deaths occurred during the median follow-up period of 10.1 years. A significant interaction between carbohydrate intake and DM was observed in the study population (interaction p = 0.061). Higher carbohydrate intake proportion was associated with an increased risk of all-cause mortality among individuals with DM (adjusted hazard ratio [HR], p-value = 1.10 [1.01-1.20], p = 0.032). Conversely, no association was observed between the proportion of carbohydrate intake and all-cause mortality in participants without DM. Additionally, both total sugar and added sugar intakes were associated with an increased risk of all-cause mortality in participants with DM (adjusted HR, p-value = 1.02 [1.01-1.04], p < 0.001 and 1.18 [1.13-1.24], p < 0.001). CONCLUSIONS: High carbohydrate (%) and added sugar intake were associated with an increased mortality risk in individuals with DM. Reducing carbohydrate intake and opting for healthy carbohydrates to mitigate mortality risk may be beneficial for individuals with DM, particularly when compared with the general population.

Assessing the Feasibility and Efficacy of Pre-Sleep Dim Light Therapy for Adults with Insomnia: A Pilot Study.

Background: Insomnia is increasingly recognized for its marked impact on public health and is often associated with various adverse health outcomes, including cardiovascular diseases and mental health disorders. The aim of this study was to investigate the efficacy of pre-sleep dim light therapy (LT) as a non-pharmacological intervention for insomnia in adults, assessing its influence on sleep parameters and circadian rhythms. Methods: A randomized, open-label, two-arm clinical trial was conducted over two weeks with 40 participants aged 20-60 years, all of whom had sleep disorders (CRIS, KCT0008501). They were allocated into control and LT groups. The LT group received exposure to warm-colored light, minimizing the blue spectrum, before bedtime. The study combined subjective evaluation via validated, sleep-related questionnaires, objective sleep assessments via actigraphy, and molecular analyses of circadian clock gene expression in peripheral blood mononuclear cells. Baseline characteristics between the two groups were compared using an independent t-test for continuous variables and the chi-squared test for categorical variables. Within-group differences were assessed using the paired t-test. Changes between groups were analyzed using linear regression, adjusting for each baseline value and body mass index. The patterns of changes in sleep parameters were calculated using a linear mixed model. Results: The LT group exhibited significant improvements in sleep quality (difference in difference [95% CI]; -2.00 [-3.58, -0.43], and sleep efficiency (LT: 84.98 vs. control: 82.11, p = 0.032), and an advanced Dim Light Melatonin Onset compared to the control group (approximately 30 min). Molecular analysis indicated a significant reduction in CRY1 gene expression after LT, suggesting an influence on circadian signals for sleep regulation. Conclusions: This study provides evidence for the efficacy of LT in improving sleep quality and circadian rhythm alignment in adults with insomnia. Despite limitations, such as a small sample size and short study duration, the results underscore the potential of LT as a viable non-pharmacological approach for insomnia. Future research should expand on these results with larger and more diverse cohorts followed over a longer period to validate and further elucidate the value of LT in sleep medicine. Trial registration: The trial was registered with the Clinical Research Information Service (KCT0008501).

Secular trends in dietary energy, carbohydrate, fat, and protein intake among Korean adults, 2010-2020 KHANES.

OBJECTIVES: The composition and balance of macronutrient intake play key roles in promoting a longer lifespan. In this study, we aimed to investigate the secular trends in carbohydrate, fat, and protein intakes in South Koreans from 2010 to 2020. METHODS: We examined the dietary nutritional intake of South Koreans using data from the Korean National Health and Nutrition Examination Survey. A total of 60,190 adults aged ≥19 y who completed the 24-h dietary recall interviews in a single day on all survey periods were included in this study. The outcomes included changes in macronutrient intake according to subgroups, such as age; sex; and the presence of diabetes, dyslipidemia, stroke, or heart disease, as well as energy intake from macronutrients. RESULTS: The study population showed a significant decrease in total energy intake from 2010 to 2020, with a corresponding decrease in the percentage of energy intake from carbohydrates (p-values for trend < 0.001). Conversely, the proportions of energy intake from proteins and fats increased during the same period (p < 0.001). Subgroup analyses revealed variations in macronutrient intake trends according to age, sex, obesity status, and underlying diseases. The analysis of trends in energy intake from various fat subtypes, total sugar, and fiber revealed a decrease in the energy intake percentage of total sugar from 2016 to 2020 and an increase in the energy intake percentage of all fat subtypes and fiber from 2013 to 2020. CONCLUSIONS: In the past 10 y, the dietary patterns in Korea have shifted toward the consumption of high-fat and high-protein diets with reduced carbohydrate intake.

Association between dairy-rich dietary pattern and metabolic dysfunction-associated steatotic liver disease: Findings from the Korean Genome and Epidemiology Study.

BACKGROUNDS: Dietary components and the development of metabolic dysfunction-associated liver disease (MASLD) are closely linked, but large-scale studies on dietary patterns and MASLD are scarce, most previous studies having focused on individual nutrients or foods rather than overall dietary patterns. Therefore, we aimed to investigate the association between dietary patterns and MASLD in Koreans. METHODS: A total of 6,052 participants from the Korean Genome and Epidemiology Study. Dietary intake was assessed using a validated Korean semiquantitative food frequency questionnaire comprising 106 food items. Principal component analysis was used to determine the major dietary patterns. Cox proportional hazard regression analysis was performed to assess the association between the incidence of MASLD and dietary patterns. RESULTS: Four major dietary patterns, namely carnivore, plant-based, dairy-rich, and starch-rich diet patterns, were identified. The carnivore, plant-based, and starch-rich diet patterns showed no significant association with incident MASLD, while the dairy-rich diet pattern was associated with a lower risk of MASLD, also showing significantly lower cumulative incidence of MASLD in the higher adherence to dairy-rich diet pattern. CONCLUSION: The dairy-rich diet pattern was significantly associated with a lower risk of MASLD in Koreans. Appropriate dietary guidance based on dietary patterns is crucial for preventing MASLD.

Comprehensive assessment of the combined impact of dyslipidemia and inflammation on chronic kidney disease development: A prospective cohort study.

BACKGROUND: There remains a limited comprehensive understanding of how dyslipidemia and chronic inflammation collectively contribute to the development of chronic kidney disease (CKD). OBJECTIVE: We aimed to identify clusters of individuals with five variables, including lipid profiles and C-reactive protein (CRP) levels, and to assess whether the clusters were associated with incident CKD risk. METHODS: We used the Korean Genome and Epidemiology Study-Ansan and Ansung data. K-means clustering analysis was performed to identify distinct clusters based on total cholesterol, triglyceride, non-high-density lipoprotein (HDL)-C, HDL-C, and CRP levels. Cox proportional hazards models were used to examine the association between incident CKD risk and the different clusters. RESULTS: During the mean 10-year follow-up period, CKD developed in 1,645 participants (690 men and 955 women) among a total of 8,053 participants with a mean age of 51.8 years. Four distinct clusters were identified: C1, low cholesterol group (LC); C2, high-density lipoprotein cholesterol group (HC); C3, insulin resistance and inflammation group (IIC); and C4, dyslipidemia and inflammation group (DIC). Cluster 4 had a significantly higher risk of incident CKD compared to clusters 2 (hazard ratio (HR) 1.455 [95% confidence interval (CI) 1.234-1.715]; p < 0.001) and cluster 1 (HR 1.264 [95% CI 1.067-1.498]; p = 0.007) after adjusting for confounders. Cluster 3 had a significantly higher risk of incident CKD compared to clusters 2 and 1. CONCLUSION: Clusters 4 and 3 had higher risk of incident CKD compared to clusters 2 and 1. The combination of dyslipidemia with inflammation or insulin resistance with inflammation appears to be pivotal in the development of incident CKD.

Dietary Habits of Newly Diagnosed Patients with Breast Cancer in Korea.

BACKGROUND: In patients with breast cancer, a healthy diet can help reduce breast cancer-specific recurrence, mortality, and comorbid chronic disease rates. There have been few studies on dietary habits immediately after breast cancer diagnosis, especially those involving the Asian population. Therefore, this study aimed to compare the nutritional habits of newly diagnosed patients with breast cancer and the general population without cancer in Korea using propensity score (PS) matching. METHODS: We conducted a case-controlled study of 157 patients with breast cancer and 2,363 cancer-free control participants from the Korea National Health and Nutrition Examination Survey. The PS values for the predicted probability of patients with breast cancer and the general population were estimated using logistic regression analysis, including age and body mass index. The dietary patterns were assessed using a 24-hour recall of 1 day and the Food Frequency Questionnaire. RESULTS: PS matching showed that patients with breast cancer consumed fewer calories and carbohydrates; however, they consumed more protein and fat compared to the general population. Compared to the general population, patients with breast cancer consumed more healthy foods such as fish, seaweed, vegetables, fruit, mixed-grain rice, and nuts; however, they also consumed more soup, stew, and red meat. CONCLUSION: Newly diagnosed patients with breast cancer have some healthy dietary habits compared to the general population. However, there is considerable room for improvement in their diet quality. Our results support the need to develop tailored dietary recommendations for patients with breast cancer during the diagnostic and posttreatment periods to improve their diet quality.

Effectiveness of the triglyceride-glucose index and triglyceride-glucose-related indices in predicting cardiovascular disease in middle-aged and older adults: A prospective cohort study.

BACKGROUNDS: Cardiovascular disease (CVD) risk assessment is a crucial component of public health. We aimed to determine the predictive value of the triglyceride-glucose (TyG) index and TyG-related indices for new-onset CVD. METHODS: This prospective study included 7,808 participants aged 40-69 years from the Ansung-Ansan cohort database. Our analysis was stratified by diabetes status. The hazard ratio (HR) with a 95% confidence interval (CI) for incident CVD was computed using multiple Cox proportional-hazards regression models. To evaluate the predictive performance of these indices for new-onset CVD, we calculated the Harrell's C-index (95% CI). RESULTS: In this study, a total of 6,890 participants did not have diabetes at baseline, while 918 participants had diabetes. In participants without diabetes, compared to the lowest tertile, fully adjusted HR and 95% CI for new-onset CVD in the highest tertile were as follows: TyG (HR 1.42, 95% CI 1.06-1.90), TyG-body mass index (BMI) (HR 1.92, 95% CI 1.19-3.10), TyG-waist circumference (WC) (HR 2.37, 95% CI 1.61-3.49), and TyG-waist-to-height ratio (WHtR) (HR 2.20, 95% CI 1.47-3.28). However, no significant associations were observed between TyG, modified TyG indices, and new-onset CVD in participants with diabetes. Notably, the C-indice of TyG-WC and TyG-WHtR were significantly higher than those of TyG and TyG-BMI in participants without diabetes. CONCLUSIONS: TyG-BMI, TyG-WC, and TyG-WHtR were associated with an increased risk of new-onset CVD in participants without diabetes. Furthermore, TyG-WC and TyG-WHtR showed better predictive performances for new-onset CVD than TyG and TyG-BMI in participants without diabetes.

Comparison of METS-IR and HOMA-IR for predicting new-onset CKD in middle-aged and older adults.

BACKGROUND: Chronic kidney disease (CKD) has emerged as a mounting public health issue worldwide; therefore, prompt identification and prevention are imperative in mitigating CKD-associated complications and mortality rate. We aimed to compare the predictive powers of the homeostatic model assessment for insulin resistance (HOMA-IR) and the metabolic score for insulin resistance (METS-IR) for CKD incidence in middle-aged and older adults. METHODS: This study used longitudinal prospective cohort data from the Korean Genome and Epidemiology Study. A total of 10,030 participants, aged 40-69 years, residing in the Ansung or Ansan regions of the Republic of Korea, were recruited between 2001 and 2002 through a two-stage cluster sampling method. We compared the predictive powers of METS-IR and HOMA-IR for CKD prevalence and incidence, respectively. CKD prevalence was measured by the area under the receiver operating characteristic (ROC) curve (AUC), and the indices' predictive performance for CKD incidence were assessed using Harrell's concordance index and time-dependent ROC curve analysis. RESULTS: A total of 9261 adults aged 40-69 years at baseline and 8243 adults without CKD were included in this study. The AUCs and 95% confidence intervals (CIs) of HOMA-IR and METS-IR for CKD prevalence at baseline were 0.577 (0.537-0.618) and 0.599 (0.560-0.637), respectively, with no significant difference (p = 0.337). The Heagerty's integrated AUC for METS-IR in predicting CKD incidence was 0.772 (95% CI 0.750-0.799), which was significantly higher than that of HOMA-IR (0.767 [95% CI 0.742-0.791], p = 0.015). CONCLUSION: METS-IR surpassed HOMA-IR in predicting CKD incidence and was as effective as HOMA-IR in predicting CKD prevalence. This implies that METS-IR could be a valuable indicator for early detection and prevention of CKD among Korean adults.

Association between experience of insulin resistance and long-term cardiovascular disease risk: findings from the Korean Genome and Epidemiology Study (KOGES).

PURPOSE: Although the correlation between insulin resistance (IR) and cardiovascular disease (CVD) risk is well-established, the impact of changes in IR status over time has received little attention. This study aimed to investigate the effect of IR on CVD risk in a large prospective cohort of middle-aged Korean adults. METHODS: We assessed 3597 participants from the Korean Genome and Epidemiology Study (KoGES). Participants were categorized as having IR if their HOMA-IR was ≥2.5 at least once during the exposure period. Multivariate Cox proportional hazards regression analysis was performed to assess hazard ratios (HRs) with 95% CIs for incident CVD after adjusting for confounders. RESULTS: Among a total of 3597 participants, 2259 did not have IR and 1138 had IR. The cumulative incidence rate of CVD in the IR group was significantly higher than that in the non-IR group (log-rank test, p = 0.015). Compared to the non-IR group, the HR and 95% CI for incident CVD in the IR group was 1.40 (1.07-1.83) in the unadjusted model. The presence of IR during the exposure period was significantly associated with a higher risk of incident CVD after adjusting for age, sex, body mass index, diabetes, hypertension, dyslipidemia, C-reactive protein, physical activity, alcohol intake, and smoking status (HR = 1.37; 95% CI: 1.01-1.84). CONCLUSION: Individuals who have experienced IR have a consistently higher likelihood of developing CVD than those who have never had IR. More intensive efforts should be made to prevent IR in middle-aged and older adults.

Oxidative balance score inversely associated with the prevalence and incidence of metabolic syndrome: analysis of two studies of the Korean population.

Background: Pro-oxidant/antioxidant imbalances leading to chronic inflammation and insulin resistance can contribute to the development of metabolic syndrome (MetS). Oxidative Balance Score (OBS), a comprehensive measure of exposure to pro- and anti-oxidants, represents an individual's total oxidative balance. This study aimed to evaluate the association between OBS and MetS using two large datasets. Methods: We analyzed data from 2,735 adults older than 19 years from the 2021 Korean National Health and Nutritional Examination Survey (KNHANES) and 5,807 adults aged 40-69 years from the Korean Genome and Epidemiology Study (KoGES). In each dataset, OBS was categorized into sex-specific tertiles (T). Results: In KNHANES, the odds ratios and 95% confidence intervals for prevalent MetS in T3, compared to T1, were 0.44 (0.29-0.65) in men and 0.34 (0.23-0.50) in women after adjusting for confounders. In KoGES, the hazard ratios and 95% confidence intervals for incident MetS in T3, compared to T1, were 0.56 (0.48-0.65) in men and 0.63 (0.55-0.73) in women after adjusting for confounders. Conclusion: OBS appears to be inversely related to MetS, which suggests that adopting lifestyle behaviors that decrease oxidative stress could be an important preventive strategy for MetS.

Association between waist circumference trajectories and incident non-alcoholic fatty liver disease.

PURPOSE: Waist circumference (WC) is linked to non-alcoholic fatty liver disease (NAFLD) incidence. However, the impact of longitudinal WC changes on NAFLD remains unclear. We investigated WC trajectories and NAFLD incidence in a large population-based cohort. METHODS: We analyzed data from 2666 participants without NAFLD, who underwent biennial check-ups for 16 years, divided into a 6-year exposure period and a 10-year event accrual period. Participants were classified into increasing and decreasing WC trajectory groups during the median 5.9-year exposure period by group-based trajectory modeling. Multiple Cox proportional hazard regression analysis estimated the hazard ratio (HR) and 95 % confidence interval (CI) for incident NAFLD. RESULTS: During the median 9.7-year event accrual period, 799 participants developed NAFLD. The increasing WC trajectory group had a higher NAFLD risk than the decreasing group, with an HR of 1.20 (95 % CI: 1.02-1.42). After adjusting for confounders, the adjusted-HR was 1.28 (95 % CI: 1.07-1.53). Subgroup analyses revealed significant findings for groups, regardless of abdominal obesity status. CONCLUSION: An increasing WC trend was associated with a higher NAFLD risk, independent of abdominal obesity status. Monitoring WC changes may facilitate early detection of NAFLD risk groups and promote lifestyle modifications to prevent NAFLD onset.

Sex-Specific Comparison Between Triglyceride Glucose Index and Modified Triglyceride Glucose Indices to Predict New-Onset Hypertension in Middle-Aged and Older Adults.

Background Triglyceride and glucose (TyG) index and TyG-related indices combined with obesity-related markers are considered important markers of insulin resistance. We aimed to examine the association between the TyG index and modified TyG indices with new-onset hypertension and their predictive ability stratified by sex. Methods and Results We analyzed data from 5414 Korean Genome and Epidemiology Study participants aged 40 to 69 years. Multiple Cox proportional hazard regression analyses were conducted to estimate the hazard ratio (HR) and 95% CI for new-onset hypertension according to sex-specific tertile groups after confounder adjustments. To evaluate the predictive performance of these indices for new-onset hypertension, we calculated Harrell's C-index (95% CI). Over a 9.5-year follow-up period, 1014 men and 1012 women developed new-onset hypertension. Compared with the lowest tertile (T) group, the adjusted HR and 95% CI for new-onset hypertension in T3 for TyG, TyG-body mass index, TyG-waist circumference, and TyG-waist-to-height ratio were 1.16 (0.95-1.40), 1.11 (0.84-1.48), 1.77 (1.38-2.27), and 1.68 (1.33-2.13) in men and 1.37 (1.13-1.66), 1.55 (1.16-2.06), 1.43 (1.15-1.79), and 1.64 (1.30-2.07) in women, respectively. The C-indices of TyG-waist-to-height ratio for new-onset hypertension were significantly higher than those of TyG and TyG-body mass index in both men and women. Conclusions TyG and TyG-body mass index were significantly associated with new-onset hypertension only in women. TyG-waist circumference and TyG-waist-to-height ratio were significantly associated with new-onset hypertension in both men and women. A sex-specific approach is required when using TyG and modified TyG indices to identify individuals at risk of incident hypertension.

Metabolic syndrome as an independent risk factor for glaucoma: a nationally representative study.

BACKGROUND: Central insulin resistance contributes to glaucoma development. Given the close association between metabolic syndrome MetS and insulin resistance, this study aimed to determine whether MetS is associated with glaucoma risk. METHODS: We analyzed data from 11,499 adults aged ≥ 19 years in the 2019-2021 Korean National Health and Nutrition Examination Survey and applied sampling weights to represent the general Korean population. Participants were classified into groups with or without MetS. Ocular hypertension (HTN) was defined as intraocular pressure > 21 mmHg. Primary open-angle glaucoma (POAG) was diagnosed based on the results of a visual field test and optical coherence tomography using the criteria published by the International Society for Geographic and Epidemiological Ophthalmology. We further divided POAG into normal tension (NTG) and POAG with ocular HTN. A spline curve was drawn to determine the dose-response relationship between the number of MetS components and risk of POAG. Odds ratios (ORs) with 95% confidence interval (CI) for POAG according to MetS status were estimated using weighted logistic regression analyses. RESULTS: The prevalence of POAG was 5.7% and 3.5%, respectively, in groups with and without MetS. We identified a dose-response relationship between the number of MetS components and risk of POAG. Unadjusted ORs (95% CI) for POAG in the group with MetS was 1.85 (1.52-2.25), compared with those without MetS. The trends persisted in adjusted models. The fully-adjusted OR (95% CI) for POAG was 1.47 (1.04-2.09) in the group with MetS. Subgroup analysis revealed that a significant relationship remained only in the NTG group (fully adjusted OR, 1.50; 95% CI 1.05-2.15). CONCLUSIONS: A comprehensive ophthalmological assessment should be considered for persons with MetS who are at increased risk of POAG, particularly NTG.

Associations of Homeostatic Model Assessment for Insulin Resistance Trajectories With Cardiovascular Disease Incidence and Mortality.

BACKGROUND: Whether trends in insulin resistance changes are related to the risk of cardiovascular disease (CVD) incidence and mortality remains unclear. We aimed to examine the association of homeostatic model assessment for insulin resistance (HOMA-IR) trajectories with CVD incidence and mortality. METHODS: Data from 6755 adults aged 40 to 69 years in the Korea Epidemiology and Genome Study were analyzed. During the exposure period (2001-2006), participants were classified into the increasing HOMA-IR trajectory group and the stable HOMA-IR trajectory group using a latent class mixture model. During the event accrual period (2007-2018), information about CVD and mortality were collected. RESULTS: During the median 9.83-year event accrual period, there were 379 (5.6%) new-onset CVD, 535 (7.9%) all-cause mortality, 102 (1.5%) CVD mortality, and 47 (0.7%) major adverse cardiovascular event mortality cases. Compared with the stable HOMA-IR trajectory group, the fully adjusted hazard ratios (95% CIs) for the increasing HOMA-IR trajectory group were 1.59 (1.04-2.44) for incident CVD, 1.87 (1.30-2.69) for all-cause mortality, 2.33 (1.11-4.89) for CVD mortality, and 3.67 (1.38-9.76) for major adverse cardiovascular event mortality. CONCLUSIONS: An increasing HOMA-IR appears to be independently and positively related to incident CVD, all-cause mortality, CVD mortality, and major adverse cardiovascular event mortality. Early lifestyle interventions for individuals with increasing HOMA-IR trend could be a practical strategy to prevent CVD and CVD mortality.