Long-term exposure to air pollution and precocious puberty in South Korea.

BACKGROUND AND AIM: The increasing prevalence of precocious puberty (PP) has emerged as a significant medical and social problem worldwide. However, research on the relationship between long-term air pollution exposure and PP has been relatively limited. We thus investigated the association between long-term air pollution exposure and the onset of PP in South Korea. METHODS: We investigated a retrospective cohort using the Korea National Health Insurance Database. Six-year-old children born from 2007 to 2009 were examined (2013-2015). We included boys ≤10 years and girls aged ≤9 years who visited hospitals for early pubertal development, were diagnosed with PP per the ICD-10 (E228, E301, and E309), and received gonadotropin-releasing hormone agonist treatment. We analyzed data for boys up until 10 years old (60-month follow-up) and for girls up to 9 years old (48-month follow-up). We assessed the association between long-term air pollution exposure and the onset of PP using a Cox proportional hazard model. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) per 1 µg/m3 increase in fine particulate matter (PM2.5) and particulate matter (PM10) and per 1 ppb increase in sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3). RESULTS: This study included 1,205,784 children aged six years old between 2013 and 2015. A positive association was found between the 48-month moving average PM2.5 (HR: 1.019; 95% CI: 1.012, 1.027), PM10 (HR: 1.009; 95% CI: 1.006, 1.013), SO2 (HR: 1.037; 95% CI: 1.018, 1.055), and O3 (HR: 1.006; 95% CI: 1.001, 1.010) exposure and PP in girls but not boys. CONCLUSIONS: This study provides valuable insights into the harmful effects of air pollution during childhood and adolescence, emphasizing that air pollution is a risk factor that should be managed and reduced.

Association of decreased estimated glomerular filtration rate with lung cancer risk in the Korean population.

Objectives: Inconsistent results are available regarding the association between low estimated glomerular filtration rate (eGFR) and lung cancer risk. We aimed to explore the risk of lung cancer according to eGFR category in the Korean population. Methods: We included 358,293 adults who underwent health checkups between 2009 and 2010, utilizing data from the National Health Insurance Service-National Sample Cohort. Participants were categorized into 3 groups based on their baseline eGFR, as determined using the Chronic Kidney Disease Epidemiology Collaboration equation: group 1 (eGFR ≥90 mL/min/1.73m2), group 2 (eGFR ≥60 to <90mL/min/1.73m2), and group 3 (eGFR <60 mL/min/1.73m2). Incidences of lung cancer were identified using the corresponding codes from the International Classification of Diseases, 10th Revision. Multivariate Cox proportional hazard models were employed to calculate the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for lung cancer incidence up to 2019. Results: In multivariate analysis, group 2 exhibited a 26.5% higher risk of developing lung cancer than group 1 (HR, 1.265; 95% CI, 1.189 to 1.346). Furthermore, group 3 demonstrated a 72.5% elevated risk of lung cancer relative to group 1 (HR, 1.725; 95% CI, 1.577 to 1.887). Among participants with dipstick proteinuria of 2+ or greater, group 3 faced a significantly higher risk of lung cancer than group 1 (HR, 2.928; 95% CI, 1.375 to 6.237). Conclusion: Low eGFR was significantly associated with increased lung cancer risk within the Korean population. A particularly robust association was observed in individuals with severe proteinuria, emphasizing the need for further investigation.

Ambient particulate matter and surrounding greenness in relation to sleep quality among pregnant women: A nationwide cohort study.

Background: Particulate air pollution and residential greenness are associated with sleep quality in the general population; however, their influence on maternal sleep quality during pregnancy has not been assessed. Objective: This cross-sectional study investigated the individual and interactive effects of exposure to particulate matter (PM) air pollution and residential greenness on sleep quality in pregnant women. Methods: Pregnant women (n = 4933) enrolled in the Korean Children's Environmental Health Study with sleep quality information and residential address were included. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). The average concentrations of PM (PM2.5 and PM10) during pregnancy were estimated through land use regression, and residential greenness in a 1000 m buffer area around participants' residences was estimated using the Normalized Difference Vegetation Index (NDVI1000-m). Modified Poisson regression models were used to estimate the associations between PM and NDVI and poor sleep quality (PSQI >5) after controlling for a range of covariates. A four-way mediation analysis was conducted to examine the mediating effects of PM. Results: After adjusting for confounders, each 10 µg/m3 increase in PM2.5 and PM10 exposure was associated with a higher risk of poor sleep quality (relative risk [RR]: 1.06; 95% confidence interval [CI]: 1.01, 1.11; and RR: 1.09; 95% CI: 1.06, 1.13, respectively), and each 0.1-unit increase in NDVI1000-m was associated with a lower risk of poor sleep quality (RR: 0.97; 95% CI: 0.95, 0.99). Mediation analysis showed that PM mediated approximately 37%-56% of the association between residential greenness and poor sleep quality. Conclusions: This study identified a positive association between residential greenness and sleep quality. Furthermore, these associations are mediated by a reduction in exposure to particulate air pollution and highlight the link between green areas, air pollution control, and human health.

Timely accessibility to healthcare resources and heatwave-related mortality in 7 major cities of South Korea: a two-stage approach with principal component analysis.

Background: Due to the ongoing effects of climate change, the incidence of heatwave-related mortality is rising globally. Improved allocation and utilization of healthcare resources could help alleviate this issue. This study aimed to identify healthcare resource factors associated with heatwave-related mortality in seven major cities of South Korea. Methods: We analyzed daily time-series data on mean temperature and all-cause mortality from 2011 to 2019. Using principal component analysis (PCA), we clustered district-level healthcare resource indicators into three principal components (PCs). To estimate district-specific heatwave-mortality risk, we used a distributed lag model with a quasi-Poisson distribution. Furthermore, a meta-regression was performed to examine the association between healthcare resources and heatwave-mortality risk. Findings: A total of 310,363 deaths were analyzed in 74 districts. The lag-cumulative heatwave-related mortality (RRs) ranged from 1.12 (95% confidence interval [CI]: 1.07, 1.17) to 1.21 (95% CI 1.05, 1.38), depending on the definitions used for heatwaves. Of the three PCs for healthcare resources (PC1: pre-hospital emergency medical service, PC2: hospital resources, PC3: timely access), timely access was associated with reduced risk of heatwave-related mortality, particularly among the elderly. Specifically, timely access to any emergency room (ER) exhibited the strongest association with lower heatwave-related mortality. Interpretation: Our findings suggest that timely access to any ER is more effective in reducing heatwave-related mortality risk than access to higher-level healthcare facilities, especially among the elderly. Therefore, healthcare resource factors and ER accessibility should be prioritized when identifying vulnerable populations for heatwaves, along with known individual and socio-demographic factors. Funding: This work was supported by the Research Program funded by the Korea Disease Control and Prevention Agency (2022-12-303), the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. 2022R1A2C2092353) and the MD-PhD/Medical Scientist Training Program through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea.

Infantile allergic diseases: a cohort study prenatal fish intake and mercury exposure context.

BACKGROUND: Allergic diseases (ADs) have been increasingly reported in infants and children over the last decade. Diet, especially the inclusion of fish intake, may help to lower the risk of ADs. However, fish also, can bioaccumulate environmental contaminants such as mercury. Hence, our study aims to determine what effects the type and frequency of fish intake have on ADs in six-month-old infants, independently and jointly with mercury exposure. METHODS: This study is part of the prospective birth cohort: Mothers and Children's Environmental Health (MOCEH) study in South Korea. Data was collected on prenatal fish intake, prenatal mercury concentration and ADs for infants aged six months for 590 eligible mother-infant pairs. Logistic regression analysis was conducted to evaluate the risk of prenatal fish intake and mercury concentration on ADs in infants. Finally, interaction between fish intake and mercury concentration affecting ADs in infants was evaluated. Hazard ratios of prenatal fish intake on ADs in 6 month old infants were calculated by prenatal mercury exposure. RESULTS: Logistic regression analysis showed that white fish (OR: 0.53; 95% CI 0.30-0.94; P < 0.05) intake frequency, once a week significantly decreased the risk of ADs in infants. Stratification analysis showed that consuming white fish once a week significantly reduced the hazard of ADs (HR: 0.44; 95% CI 0.21-0.92; P < 0.05) in infants in the high-mercury (≥ 50th percentile) exposure group. CONCLUSION: The result indicates that prenatal white fish intake at least once a week reduces the risk of ADs in infants, especially in the group with high prenatal mercury exposure.

Disparities in the association between ambient temperature and preterm birth according to individual and regional characteristics: a nationwide time-stratified case-crossover study.

BACKGROUND: Several studies have reported that climate change elevates heat exposure in pregnant women and high temperatures during pregnancy are associated with preterm births (PTBs). Although the association might be disproportionate, related evidence remains sparse. We evaluated the disproportionate risk of PTB associated with ambient temperature during pregnancy by individual and regional characteristics in South Korea. METHODS: We collected data on birth certificates and daily mean temperatures during the period from 2011 to 2019. A time-stratified case-crossover design was used to investigate the association between temperature and PTB and stratified analyses were conducted to examine the effect modification of individual and regional characteristics. RESULTS: A total of 160,067 singleton PTBs were recorded in Korea from 2011 to 2019. A 5℃ increase in the mean temperature during the last four weeks before delivery was associated with an increased risk of PTB with an odds ratio (OR) of 1.03 (95% confidence interval [CI]: 1.02, 1.05), and the association was more evident in mothers aged ≥35 years (OR: 1.06 [95% CI: 1.03, 1.10]) and with low education levels (OR: 1.04 [95% CI: 1.02, 1.05]). Additionally, the estimated risk was evident in districts with lower medical resources and more prominent disparities were shown by individual and regional characteristics in rural areas than in urban areas. CONCLUSIONS: This study provides evidence that the risk of PTB related to ambient temperature is disproportionate by individual and regional characteristics and suggests the need for public health policies to alleviate the disparities, especially in rural areas.

Fluctuating risk of acute kidney injury-related mortality for four weeks after exposure to air pollution: A multi-country time-series study in 6 countries.

BACKGROUND: Recent studies have reported that air pollution is related to kidney diseases. However, the global evidence on the risk of death from acute kidney injury (AKI) owing to air pollution is limited. Therefore, we investigated the association between short-term exposure to air pollution-particulate matter ≤ 2.5 µm (PM2.5), ozone (O3), and nitrogen dioxide (NO2)-and AKI-related mortality using a multi-country dataset. METHODS: This study included 41,379 AKI-related deaths in 136 locations in six countries during 1987-2018. A novel case time-series design was applied to each air pollutant during 0-28 lag days to estimate the association between air pollution and AKI-related deaths. Moreover, we calculated AKI deaths attributable to non-compliance with the World Health Organization (WHO) air quality guidelines. RESULTS: The relative risks (95% confidence interval) of AKI-related deaths are 1.052 (1.003, 1.103), 1.022 (0.994, 1.050), and 1.022 (0.982, 1.063) for 5, 10, and 10 µg/m3 increase in lag 0-28 days of PM2.5, warm-season O3, and NO2, respectively. The lag-distributed association showed that the risk appeared immediately on the day of exposure to air pollution, gradually decreased, and then increased again reaching the peak approximately 20 days after exposure to PM2.5 and O3. We also found that 1.9%, 6.3%, and 5.2% of AKI deaths were attributed to PM2.5, warm-season O3, and NO2 concentrations above the WHO guidelines. CONCLUSIONS: This study provides evidence that public health policies to reduce air pollution may alleviate the burden of death from AKI and suggests the need to investigate the several pathways between air pollution and AKI death.

Association between long-term PM2.5 exposure and risk of Kawasaki disease in children: A nationwide longitudinal cohort study.

BACKGROUND: Based on previous studies suggesting air pollution as a potential risk factor for Kawasaki Disease (KD), we examined the association of long-term exposure to childhood fine particulate matter (PM2.5) with the risk of KD. METHODS: We used National Health Insurance Service-National Sample Cohort data from 2002 to 2019, which included beneficiaries aged 0 years at enrollment and followed-up until the onset of KD or age 5 years. The onset of KD was defined as the first hospital visit record with a primary diagnostic code of M30.3, based on the 10th revision of the International Classification of Diseases, and with an intravenous immunoglobulin (IVIG) prescription. We assigned PM2.5 concentrations to 226 districts, based on mean annual predictions from a machine learning-based ensemble prediction model. We performed Cox proportional-hazards modeling with time-varying exposures and confounders. RESULTS: We identified 134,634 individuals aged five or less at enrollment and, of these, 1220 individuals who had a KD onset and an IVIG prescription during study period. The average annual concentration of PM2.5 exposed to the entire cohort was 28.2 µg/m³ (Standard Deviation 2.9). For each 5 µg/m³ increase in annual PM2.5 concentration, the hazard ratio of KD was 1.21 (95% CI 1.05-1.39). CONCLUSIONS: In this nationwide, population-based, cohort study, long-term childhood exposure to PM2.5 was associated with an increased incidence of KD in children. The study highlights plausible mechanisms for the association between PM2.5 and KD, but further studies are needed to confirm our findings.

Decreased estimated glomerular filtration rate increase the risk of pancreatic cancer: A nationwide retrospective cohort study.

BACKGROUND AND AIM: Decreased kidney function is a putative risk factor for various cancers. However, few studies have investigated the association between a decreased estimated glomerular filtration rate (eGFR) and incident pancreatic cancer. We aimed to investigate the risk of incident pancreatic cancer according to eGFR categories. METHODS: In this retrospective cohort study, we included 359 721 adults who underwent health checkups in 2009 or 2010 by using the Korean National Health Insurance Database. The study population was categorized into four groups by eGFR (mL/min/1.73 m2 ) using the Chronic Kidney Disease Epidemiology Collaboration equation: group 1 (eGFR < 45), group 2 (eGFR ≥ 45 to < 60), group 3 (eGFR ≥ 60 to < 90), and group 4 (eGFR ≥ 90). Multivariate Cox proportional hazards models were used to determine the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of pancreatic cancer until 2019 by comparing the eGFR groups. RESULTS: During the 3 493 589.05 person-years of follow-up, 1702 pancreatic cancer cases were identified. Compared with group 4 (eGFR ≥ 90), HRs and 95% CIs for the incidence of pancreatic cancer were 1.39 (1.24-1.56) for group 3 (eGFR ≥ 60 to < 90), 1.79 (1.47-2.16) for group 2 (eGFR ≥ 45 to < 60), and 2.05 (1.62-2.60) for group 1 (eGFR < 45) in the multivariate adjusted model. CONCLUSIONS: Decreased eGFR was significantly associated with an increased risk of pancreatic cancer in Korean population. Further studies are needed to investigate the relationship between a decreased eGFR and the risk of pancreatic cancer in other ethnic groups.

Heat wave exposure and increased heat-related hospitalizations in young children in South Korea: A time-series study.

BACKGROUND: Numerous studies have investigated the association between heat wave exposure increased heat-related hospitalizations in the general population. However, little is known about heat-related morbidity in young children who are more vulnerable than the general population. Therefore, we aimed to evaluate the association between hospitalization for heat-related illness in children and heat wave exposure in South Korea. METHODS: We used the National Health Insurance Service (NHIS) database, which provides medical records from 2015 to 2019 in South Korea. We defined daily hospitalizations for heat-related illness of children younger than five years during the summer period (June to August). We considered the definition of heat waves considering the absolute temperature and percentile. A total of 12 different heat waves were used. A time-series analysis was used to investigate the association between heat wave exposure and heat-related hospitalization among children younger than five years. We used a two-stage design involving a meta-analysis after modeling by each region. RESULTS: We included 16,879 daily heat-related hospitalizations among children younger than five years. Overall, heat wave exposure within two days was most related for heat-related hospitalizations in young children. The relative risk (RR) due to heat wave exposure within two days (lag2) (12 definitions: 70th to 90th percentile of maximum temperature) ranged from 1.038 (95% confidence interval (CI): 0.971, 1.110) to 1.083 (95% CI: 1.036, 1.133). We found that boys were more vulnerable to heat exposure than girls. In addition, we found that urban areas were more vulnerable to heat exposure than rural areas. CONCLUSIONS: In our study, heat wave exposure during summer was found to be associated with an increased risk of hospitalization for heat-related illness among children younger than five years. Our findings suggest the need for summer heat wave management and prevention for children.

Changes in proteinuria and the associated risks of ischemic heart disease, acute myocardial infarction, and angina pectoris in Korean population.

OBJECTIVES: Proteinuria is widely used to predict cardiovascular risk. However, there is insufficient evidence to predict how changes in proteinuria may affect the incidence of cardiovascular disease. METHODS: The study included 265,236 Korean adults who underwent health checkups in 2003-2004 and 2007-2008. They were categorized into 4 groups based on changes in proteinuria (negative: negative → negative; resolved: proteinuria ≥1+ → negative; incident: negative → proteinuria ≥1+; persistent: proteinuria ≥1+ → proteinuria ≥1+). We conducted 6 years of follow-up to identify the risks of developing ischemic heart disease (IHD), acute myocardial infarction (AMI), and angina pectoris according to changes in proteinuria. A multivariate Cox proportional-hazards model was used to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident IHD, AMI, and angina pectoris. RESULTS: The IHD risk (expressed as HR [95% CI]) was the highest for persistent proteinuria, followed in descending order by incident and resolved proteinuria, compared with negative proteinuria (negative: reference, resolved: 1.211 [95% CI, 1.104 to 1.329], incident: 1.288 [95% CI, 1.184 to 1.400], and persistent: 1.578 [95% CI, 1.324 to 1.881]). The same pattern was associated with AMI (negative: reference, resolved: 1.401 [95% CI, 1.048 to 1.872], incident: 1.606 [95% CI, 1.268 to 2.035], and persistent: 2.069 [95% CI, 1.281 to 3.342]) and angina pectoris (negative: reference, resolved: 1.184 [95% CI, 1.065 to 1.316], incident: 1.275 [95% CI, 1.160 to 1.401], and persistent: 1.554 [95% CI, 1.272 to 1.899]). CONCLUSIONS: Experiencing proteinuria increased the risks of IHD, AMI, and angina pectoris even after proteinuria resolved.

Changes in smoking status, amount of smoking and their relation to the risk of microvascular complications in men with diabetes mellitus.

BACKGROUND: Smoking is a definite risk factor for macrovascular complications in diabetes mellitus (DM). However, the effect of smoking on microvascular complications is inconclusive. METHOD: Study participants were 26,673 diabetic men who received health check-up both in 2003-2004 and 2009, excluding women. Assessing smoking status (never, quitting and current) at 2003-2004 and 2009, changes in smoking status were categorised into 7 groups (never - never, never - quitting, never - current, quitting-quitting, quitting-current, current-quitting and current-current). Smoking amount was categorised into never, light (0-10 pack years), moderate (10-20 pack years), and heavy smoking (>20 pack years) based on 2009 data. They were followed-up until 2013 to identify incident microvascular complications. We calculated the adjusted hazard ratios (HR) and 95% confidence interval (CI) (adjusted HR [95% CI]) for incident microvascular complications according to changes in smoking status and smoking amount. RESULTS: Current-quitting (1.271 [1.050-1.538]), current-current (1.243 [1.070-1.444]) and heavy smoking (1.238 [1.078-1.422]) were associated with an increased risk of overall microvascular complications. The risk of nephropathy increased in current-current smoking (1.429 [1.098-1.860]) and heavy smoking (1.357 [1.061-1.734]). An increased risk of neuropathy was observed in current-quitting smoking (1.360 [1.076-1.719]), current-current smoking (1.237 [1.025-1.492]) and heavy smoking (1.246 [1.048-1.481]). However, we couldn't see the interpretable findings for the association between smoking and retinopathy. CONCLUSIONS: Lasting and heavy smoking increases the risk of microvascular complications, including nephropathy and neuropathy. Quitting smoking and reducing smoking amount are imperative in preventing microvascular complications in DM patients.

Development of a semi-quantitative food frequency questionnaire for dietary intake of elementary school children: data from the Seventh Korea National Health and Nutrition Examination Survey.

BACKGROUND/OBJECTIVES: In Korea, studies of diet in elementary school children are hindered by the need for a comprehensive dietary assessment tool. Thus, the aim of this study was to develop a semi-quantitative food frequency questionnaire (FFQ) for Korean elementary school children. SUBJECTS/METHODS: The 24-h recall data for 1,624 subjects aged 6-11 yrs from the seventh Korea National Health and Nutrition Examination Survey were used to extract the items included in the questionnaire. The FFQ items were developed by selecting major dishes based on the results of nutritional contribution and between-person variability for energy and 14 nutrients (carbohydrate, protein, fat, crude fiber, calcium, phosphorous, iron, sodium, potassium, vitamin A, thiamin, riboflavin, niacin, and vitamin C). We selected the major dishes with over 90% of the total contribution to each nutrient and with over 90% of the accumulated R2 for each nutrient. Among the 452 dishes, we selected 248 dishes contributing more than 1% of the total consumption. RESULTS: Finally, the FFQ included 107 items combined from 248 dishes based on nutrient profile and recipe. The FFQ items accounted for an average of 88.6% of the energy, 14 nutrient intakes, and 91.4% of the between-person variability. Quantities of dietary intake were assessed by 9 categories of frequency and 3 categories of portion size. Percentages of coverage for energy, protein, fat, carbohydrate, and calcium were 90.2%, 87.8%, 89.9%, 90.8%, and 88.7%, respectively. CONCLUSIONS: We developed a dish-based, semi-quantitative FFQ comprising 107 items for Korean elementary school children aged 6 to 11. Further studies are needed to evaluate the reproducibility and validity of this FFQ for elementary school children.

Causal relationship between particulate matter 2.5 and diabetes: two sample Mendelian randomization.

Backgrounds: Many studies have shown particulate matter has emerged as one of the major environmental risk factors for diabetes; however, studies on the causal relationship between particulate matter 2.5 (PM2.5) and diabetes based on genetic approaches are scarce. The study estimated the causal relationship between diabetes and PM2.5 using two sample mendelian randomization (TSMR). Methods: We collected genetic data from European ancestry publicly available genome wide association studies (GWAS) summary data through the MR-BASE repository. The IEU GWAS information output PM2.5 from the Single nucleotide polymorphisms (SNPs) GWAS pipeline using pheasant-derived variables (Consortium = MRC-IEU, sample size: 423,796). The annual relationship of PM2.5 (2010) were modeled for each address using a Land Use Regression model developed as part of the European Study of Cohorts for Air Pollution Effects. Diabetes GWAS information (Consortium = MRC-IEU, sample size: 461,578) were used, and the genetic variants were used as the instrumental variables (IVs). We performed three representative Mendelian Randomization (MR) methods: Inverse Variance Weighted regression (IVW), Egger, and weighted median for causal relationship using genetic variants. Furthermore, we used a novel method called MR Mixture to identify outlier SNPs. Results: From the IVW method, we revealed the causal relationship between PM2.5 and diabetes (Odds ratio [OR]: 1.041, 95% CI: 1.008-1.076, P = 0.016), and the finding was substantiated by the absence of any directional horizontal pleiotropy through MR-Egger regression (ß = 0.016, P = 0.687). From the IVW fixed-effect method (i.e., one of the MR machine learning mixture methods), we excluded outlier SNP (rs1537371) and showed the best predictive model (AUC = 0.72) with a causal relationship between PM2.5 and diabetes (OR: 1.028, 95% CI: 1.006-1.049, P = 0.012). Conclusion: We identified the hypothesis that there is a causal relationship between PM2.5 and diabetes in the European population, using MR methods.

Meal-Based Intervention on Health Promotion in Middle-Aged Women: A Pilot Study.

Middle-aged women belong to a risk group for metabolic dysregulation and menopausal symptoms, mainly due to a dramatic hormonal shift. Supplementation with functional compounds or a single nutrient has been dominantly explored as a nutritional approach for improving aging-related health parameters. However, a meal-based approach might be another strategy for promoting the overall health of the target population. This pilot study aimed to develop a meal-based intervention for middle-aged women and to evaluate its potential health benefits. Considering the nutrient intake status of Korean middle-aged women, diets enriched with four major nutrients (isoflavone, omega-3, fiber, and calcium) were designed and provided to forty-nine women aged 50 to 65 with mild levels of menopausal symptoms for 8 weeks. In the post-intervention phase, they showed reduced body weight and body fat, and improved biochemical metabolic parameters with decreased levels of cholesterol, low-density lipoprotein-cholesterol, ApoB, and fasting insulin. Moreover, bone resorption markers and menopause symptoms were lower in the post-intervention phase. In conclusion, the meal-based intervention might be a prominent strategy for overall health promotion in relatively healthy middle-aged women and further investigation is needed to test its efficacy with a randomized controlled study.

Coffee intake and hypertension in Korean adults: results from KNHANES 2012-2016.

BACKGROUND: Coffee is the most popular and widely consumed drink in the world. Coffee consumption seems to have both benefits and risk with respect to hypertension; results from studies evaluating effect of frequency of coffee consumption on risk of hypertension are mixed and inconsistent. Hence, we investigated the association of coffee consumption and hypertension in Korean adults. METHODS: Data from Korean National Health and Nutrition Examination Survey (KNHANES) 2012-2016 was obtained and 12,133 eligible participants were selected. The coffee consumption was attained using a food frequency questionnaire. Subsequently coffee intake was grouped into two categories: ≤2 and > 2 servings per day. Hypertension status was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg, use of antihypertensive drug treatment, or both. Multivariable logistic regression analysis was used to examine the association of coffee consumption and hypertension. RESULTS: Logistic regression analysis showed that consumption of more than two servings of coffee a day was inversely associated with hypertension with odds ratio (OR) 0.84 (95% confidence interval [CI], 0.73-0.99). Similar results were seen in the propensity score-matched analysis (OR, 0.83; 95% CI, 0.69-0.98). Adults having age more than median value (OR, 0.76; 95% CI, 0.65-0.89) and normal cholesterol (OR, 0.84; 95% CI, 0.70-0.99) had significantly inverse association with hypertension, when coffee consumption was more than two servings daily. CONCLUSIONS: More than two servings of coffee intake per day was inversely associated with hypertension as compared to consumption of ≤ 2 servings coffee per day.

The effect of residential greenness during pregnancy on infant neurodevelopment using propensity score weighting: A prospective mother-infant paired cohort study.

BACKGROUND: While prior studies have suggested an association between green spaces and infant neurodevelopment, the causal effect of green space exposure during pregnancy has not been fully investigated. This study aimed to identify with causal inference the effect of exposure to residential greenness during pregnancy on infants' mental-psychomotor development and the role of maternal education in modifying this association. METHODS: We prospectively collected data of pregnant women and their infants from Mothers and Children Environmental Health cohort study. Based on residential addresses, we compiled information on the percent of green space using different buffer distances (100 m, 300 m, and 500 m) and air pollution (PM2.5). Infant neurodevelopment was measured at 6 months of age using the Korean Bayley Scales of Infant Development II Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI). Generalized propensity scores (GPSs) were estimated from machine-learning (ML) algorithms. We deduced causal inference through GPS adjustment and weighting approaches. Further analyses confirmed whether the association was altered by maternal academic background. RESULTS: A total of 845 mother-infant pairs from the cohort study were included. We found that exposure to green spaces was robustly associated with infants' mental development. For example, an increase in % green space within 300 m increased the MDI by 14.32 (95 % confidence interval [CI], 3.44-25.2) in the weighting approach. Additionally, the association was even more noticeable for mothers with college degrees or above: an increase in % green space within 300 m increased the MDI by 23.69 (95 % CI, 8.53-38.85) and the PDI by 22.45 (95 % CI, 2.58-42.33) in the weighting approach. This association did not appear in mothers without college degrees. CONCLUSION: Exposure to green spaces during pregnancy showed a beneficial relationship with infant mental development. Maternal academic background could modify the impact of green space exposure on infant neurodevelopment.

Association of type 2 diabetes mellitus with lung cancer in patients with chronic obstructive pulmonary disease.

Background: Patients with chronic obstructive pulmonary disease (COPD) have an increased risk of developing lung cancer. Some studies have also suggested that diabetes mellitus (DM) may increase the risk of developing lung cancer. This study aimed to investigate whether type 2 DM (T2DM) is associated with an increased risk of lung cancer in patients with COPD. Materials and methods: We conducted a retrospective analysis on two cohorts: the National Health Insurance Service-National Sample Cohort (NHIS-NSC) of Korea and the Common Data Model (CDM) database of a university hospital. Among patients newly diagnosed with COPD in each cohort, those with a lung cancer diagnosis were included, and a control group was selected through propensity score matching. We used the Kaplan-Meier analysis and Cox proportional hazard models to compare lung cancer incidence between patients with COPD and T2DM and those without T2DM. Results: In the NHIS-NSC and CDM cohorts, we enrolled 3,474 and 858 patients with COPD, respectively. In both cohorts, T2DM was associated with an increased risk of lung cancer [NHIS-NSC: adjusted hazard ratio (aHR), 1.20; 95% confidence interval (CI), 1.02-1.41; and CDM: aHR, 1.45; 95% CI, 1.02-2.07). Furthermore, in the NHIS-NSC, among patients with COPD and T2DM, the risk of lung cancer was higher in current smokers than in never-smokers (aHR, 1.45; 95% CI, 1.09-1.91); in smokers with ≥30 pack-years than in never-smokers (aHR, 1.82; 95% CI, 1.49-2.25); and in rural residents than in metropolitan residents (aHR, 1.33; 95% CI, 1.06-1.68). Conclusion: Our findings suggest that patients with COPD and T2DM may have an increased risk of developing lung cancer compared to those without T2DM.

COVID-19, maternal, and neonatal outcomes: National Mother-Child Cohort (NMCC) of K-COV-N cohort in South Korea.

Throughout the COVID-19 pandemic, pregnant women have been classified as a vulnerable population. However, the evidence on the effect of infection during pregnancy on maternal and neonatal outcomes is still uncertain, and related research comprising a large population of pregnant women in Asian countries is limited. We constructed a national cohort including mothers and children (369,887 pairs) registered in the Prevention Agency-COVID-19-National Health Insurance Service (COV-N), from January 1, 2020 to March 31, 2022. We performed propensity score matchings and generalized estimation equation models to estimate the effect of COVID-19 on maternal and neonatal outcomes. In summary, we found little evidence of the effect of COVID-19 infection during pregnancy on maternal and neonatal outcomes; however, a relationship between COVID-19 infection in the second trimester and postpartum hemorrhages was discovered (Odds ratio (OR) of Delta period: 2.26, 95% Confidence intervals (CI): 1.26, 4.05). In addition, neonatal intensive care unit (NICU) admissions increased due to COVID-19 infection (pre-Delta period: 2.31, 95% CI: 1.31, 4.10; Delta period: 1.99, 95% CI: 1.47, 2.69; Omicron period: 2.36, 95% CI: 1.75, 3.18). Based on the national retrospective cohort study data, this study investigated the effects of COVID-19 infection on maternal and neonatal outcomes in Korea from the pre-Delta to the initial Omicron epidemic periods. Our evidence suggests that the timely and successful policies of the government and academia in response to COVID-19 infections in newborns in Korea may cause an increase in NICU admissions, but nonetheless, they prevent adverse maternal and neonatal outcomes simultaneously.

Hospital admission risks and excess costs for neurological symptoms attributable to long-term exposure to fine particulate matter in New York State, USA.

BACKGROUND: Although emerging evidence suggests that PM2.5 is linked to neurological symptoms (NSs) via neuroinflammation, relevant studies are scarce. This study aimed to investigate the risks and excess costs of hospital admission for five NSs-fatigue, headache, dizziness, convulsion, and paralysis-attributable to long-term exposure to PM2.5 in New York State, USA. METHODS: We analyzed the New York Statewide Planning and Research Cooperative System (SPARCS) from 2010 to 2016. A Bayesian hierarchical model with integrated nested Laplace approximations was performed to estimate the risks and excess costs of hospital admission for NSs due to long-term exposure to PM2.5 at the county level. RESULTS: A 1 µg/m3 increase in lag 0-1 years PM2.5 was associated with an increased risk of headache and convulsion by 1.06 (1.01, 1.11) and 1.04 (1.01, 1.06), respectively. The excess hospital admission cost for five NSs attributable to lag 0-1 years PM2.5 above the new World Health Organization guideline (annual standard: 5 µg/m3) was $200.24 (95% CI: 6.00, 376.96) million during 2011-2016, recording the highest for convulsion ($153.73 [95% CI: 63.61, 244.19] million). CONCLUSIONS: This study provides quantitative estimates of risks and excess costs for NSs attributable to long-term PM2.5 and suggests that policies that reduce long-term PM2.5 concentration in accordance with the new WHO air quality guidelines can yield substantial health and economic benefits related to NSs in the New York State population.