Associations of obesity indices change with cardiovascular outcomes: a dose-response meta-analysis.

BACKGROUND: Little is known about the degrees and shapes of associations of changes in obesity indices with cardiovascular disease (CVD) and mortality risks. We aimed to conduct a dose-response meta-analysis for the associations of changes in weight, body mass index (BMI), waist circumference (WC), waist-to-hip ratio, and waist-to-height ratio with CVD events, CVD-specific deaths, and all-cause mortality. METHODS: We searched MEDLINE via OvidSP, Embase via OvidSP, Web of Science, CINAHL, and Scopus for articles published before January 8th, 2023. Dose-response relationships were modeled using the one-stage mixed-effects meta-analysis. Random-effects models were used to pool the relative risk (RR) and 95% confidence interval (CI). RESULTS: We included 122 articles. Weight change was negatively associated with deaths from CVD and any cause, while WC change elevated CVD-specific mortality. Non-linear relationships also confirmed the adverse effects of increased WC on CVD-specific mortality. Additionally, gains of 5 kg in weight and 1 kg/m2 in BMI or more were associated with elevated CVD events, especially among young adults and individuals without CVD. Conversely, reductions of 5 kg in weight and 1 kg/m2 in BMI or more were associated with higher CVD-specific and all-cause deaths than increased counterparts, particularly among old adults and individuals with CVD. Similar non-linear relationships between relative changes in weight and BMI and deaths from CVD and any cause were observed. CONCLUSIONS: The effects of changes in weight and BMI on CVD outcomes were affected by age and cardiovascular health. Tailored weight management and avoidance of increased WC should be recommended.

Trajectories of body mass index before the diagnosis of type 2 diabetes in a cohort of Taiwanese adults.

BACKGROUND: Although the prevalence of overweight/obesity is lower in Asian countries, the risk of type 2 diabetes (T2DM) is disproportionally higher. We identified and characterized the trajectory patterns of body mass index (BMI) before the onset of T2DM in a Taiwanese population. METHODS: Using the Taiwan MJ cohort study, we sampled the health examination data of 22,934 participants, including 7618 cases of T2DM and 15,316 controls. We used latent class trajectory analysis to identify distinct groups of pre-disease BMI trajectory. To compare the trajectories of cardiometabolic risk factors among different groups, we used linear mixed-effects models. RESULTS: These 22,934 participants included 13,074 men (57%) and 9860 women (43%) who were on average followed for 9.0 years. We identified three distinct pre-disease BMI trajectories in cases: "stable overweight" (n = 7016, 92.1%), "weight gain" (n = 333, 4.4%) and "obesity" (n = 269, 3.5%). The "stable overweight" group had a mean BMI of 24.6 kg/m2 at 15 years prior to diagnosis, had a 1.2 unit increase during follow-up, and had a mean BMI of 25.8 kg/m2 at the time of diagnosis. The "weight gain" group had the most increasing trends in blood pressure/low-density lipoprotein cholesterol over time. CONCLUSION: The BMI trajectory patterns among individuals who later developed diabetes in Taiwan seemed comparable to that of Western populations, but our population developed T2DM at a much lower BMI. Given that most cases belong to the "stable overweight" group, we also support using a population-based strategy for diabetes prevention instead of focusing on the high risk individuals.

Using individual approach to examine the association between urban heat island and preterm birth: A nationwide cohort study in China.

BACKGROUND: Evidence suggests that maternal exposure to heat might increase the risk of preterm birth (PTB), but no study has investigated the effect from urban heat island (UHI) at individual level. AIMS: Our study aimed to investigate the association between individual UHI exposure and PTB. METHODS: We utilized data from the ongoing China Birth Cohort Study (CBCS), encompassing 103,040 birth records up to December 2020. UHI exposure was estimated for each participant using a novel individual assessment method based on temperature data and satellite-derived land cover data. We used generalized linear mixed-effects models to estimate the association between UHI exposure and PTB, adjusting for potential confounders including maternal characteristics and environmental factors. RESULTS: Consistent and statistically significant associations between UHI exposure and PTB were observed up to 21 days before birth. A 5 °C increment in UHI exposure was associated with 27 % higher risk (OR = 1.27, 95 % confident interval: 1.20, 1.34) of preterm birth in lagged day 1. Stratified analysis indicated that the associations were more pronounced in participants who were older, had higher pre-pregnancy body mass index level, of higher socioeconomic status and living in greener areas. CONCLUSION: Maternal exposure to UHI was associated with increased risk of PTB. These findings have implications for developing targeted interventions for susceptible subgroups of pregnant women. More research is needed to validate our findings of increased risk of preterm birth due to UHI exposure among pregnant women.

Impact of heat on emergency hospital admissions related to kidney diseases in Texas: Uncovering racial disparities.

BACKGROUND AND OBJECTIVE: While impact of heat exposure on human health is well-documented, limited research exists on its effect on kidney disease hospital admissions especially in Texas, a state with diverse demographics and a high heat-related death rate. We aimed to explore the link between high temperatures and emergency kidney disease hospital admissions across 12 Texas Metropolitan Statistical Areas (MSAs) from 2004 to 2013, considering causes, age groups, and ethnic populations. METHODS: To investigate the correlation between high temperatures and emergency hospital admissions, we utilized MSA-level hospital admission and weather data. We employed a Generalized Additive Model to calculate the association specific to each MSA, and then performed a random effects meta-analysis to estimate the overall correlation. Analyses were stratified by age groups, admission causes, and racial/ethnic disparities. Sensitivity analysis involved lag modifications and ozone inclusion in the model. RESULTS: Our analysis found that each 1 °C increase in temperature was associated with a 1.73 % (95 % CI [1.43, 2.03]) increase in hospital admissions related to all types of kidney diseases. Besides, the effect estimates varied across different age groups and specific types of kidney diseases. We observed statistically significant associations between high temperatures and emergency hospital admissions for Acute Kidney Injury (AKI) (3.34 % (95 % CI [2.86, 3.82])), Kidney Stone (1.76 % (95 % CI [0.94, 2.60])), and Urinary Tract Infections (UTI) (1.06 % (95 % CI [0.61, 1.51])). Our research findings indicate disparities in certain Metropolitan Statistical Areas (MSAs). In Austin, Houston, San Antonio, and Dallas metropolitan areas, the estimated effects are more pronounced for African Americans when compared to the White population. Additionally, in Dallas, Houston, El Paso, and San Antonio, the estimated effects are greater for the Hispanic group compared to the Non-Hispanic group. CONCLUSIONS: This study finds a strong link between higher temperatures and kidney disease-related hospital admissions in Texas, especially for AKI. Public health actions are necessary to address these temperature-related health risks, including targeted kidney health initiatives. More research is needed to understand the mechanisms and address health disparities among racial/ethnic groups.

Leisure-time physical activity mitigated the cognitive effect of PM2.5 and PM2.5 components exposure: Evidence from a nationwide longitudinal study.

BACKGROUND: Exposure to fine particulate matter (PM2.5) impairs cognition, while physical activity (PA) improves cognitive function. However, whether taking PA with PM2.5 exposure is still beneficial to cognition remains unknown. METHODS: We utilized national representative longitudinal data from the China Family Panel Study (CFPS), comprising a total sample of 108,099 from 2010 to 2018 in three waves. Cognitive performance and leisure-time PA were measured using the standard cognitive module and Godin-Shephard Leisure-Time Physical Activity Questionnaire. Gridded overall PM2.5 and major chemical components of PM2.5 were estimated using a two-stage machine learning model and matched to each participant based on their residential location. Mixed-effect models and difference-in-difference models were employed to investigate the individual and joint effects of total PM2.5, PM2.5 components, and leisure-time PA on cognition. RESULTS: Every 1 µg/m3 increase in PM2.5 was associated with a -0.035 (95% confidence interval [CI] = -0.052, -0.018) point change in cognitive score. All PM2.5 components exhibited negative associations with cognitive change, with black carbon (BC) contributing the most significant cognitive decline (ß = -1.025, 95% CI = -1.367, -0.683). Every one-time (or one-hour) increase in leisure-time PA frequency (or PA time) per week was associated with an increase in cognitive score by 0.576 (0.270) points (PA frequency: 95% CI = 0.544, 0.608, PA time: 95% CI = 0.248, 0.293). PA frequency (ß = -0.005, 95% CI = -0.006, -0.003) and PA time (ß = -0.002, 95% CI = -0.003, -0.001) exhibited interactive effects with PM2.5. Increased PA frequency and time were more beneficial to cognitive function in the low PM2.5 exposure group compared to those exposed to high PM2.5 levels. Moreover, relative to lower PM2.5 exposure, the cognitive benefits of physically active individuals with higher PM2.5 exposure were attenuated but still improved cognition when compared to those with no PA. CONCLUSION: Engaging in leisure-time PA provides cognitive benefits even under PM2.5 exposure, although PM2.5 exposure attenuates these benefits. Among all PM2.5 components, BC demonstrated the most significant cognitive hazard and interaction with leisure-time PA. Promoting PA as a preventive measure may offer a cost-effective and convenient strategy to mitigate the negative impact of PM2.5 exposure on cognition. There is no excuse to avoid PA under PM2.5 exposure, as its cognitive benefits persist even in polluted environments.

Fine and ultrafine airborne PM influence inflammation response of young adults and toxicological responses in vitro.

Little evidence is available regarding the impact of different sizes of inhaled particulate matter (PM) on inflammatory responses in healthy young adults in connection with toxicological responses. We conducted a five-time repeated measurement panel study on 88 healthy young college students in Guangzhou, China from December 2017 to January 2018. Blood samples were collected from each participant and tested for tumor necrosis factor alpha (TNF-α) levels every week for 5 consecutive weeks. Mass concentrations of ambient PM2.5, PM1, PM0.5 and number concentrations of ambient PM0.1 were measured. RAW 264.7 macrophages were exposed to PM (PM10-2.5, PM2.5-1, PM1-0.2, PM0.2) collected at the same time as the panel study. Cytotoxicity, oxidation and inflammatory parameters, cell cycle and genotoxicity were tested. Particles were characterized for their chemical composition. The trends of associations between PM2.5, PM1, PM0.5 and TNF-α level were consistent in lag 0 and 3 days, and the relative risk decreased as the particle size decreased. All the ambient air pollutants had the similar change trends in lag 1, 4 and 5 days. Similar results in RAW 264.7 macrophages were found; PM10-2.5 induced the greatest TNF-α and macrophage inflammatory protein 2 (MIP-2) productions and oxidative damage. PM1-0.2 and PM0.2 induced more significant dose-dependent increases of cell cycle and genotoxic response. In the component concentrations of PM samples, metal elements were PM10-2.5 > PM2.5-1 > PM0.2 ≥ PM1-0.2; ions and polycyclic aromatic hydrocarbons (PAHs) were PM0.2 > PM1-0.2 > PM2.5-1 > PM10-2.5. Our results suggested that exposure to all particle sizes was significantly associated with inflammation among healthy young adults and toxicological responses in RAW 264.7 macrophages. Different human and toxicological reactions caused by PM samples indicated the importance of investigating various particle sizes.

Diverging Trends and Expanding Educational Gaps in Smoking in China.

INTRODUCTION: The male smoking rate in China declined moderately through the 1990s and early 2000s, but the decline has since stagnated. It is unclear why the decline stalled and whether it stalled uniformly across all social strata. Theories that view socioeconomic status as a fundamental cause of health predict that socioeconomic gaps in smoking may widen, but theories emphasizing the cultural context of health behavior cast doubt on the prediction. We investigated changes in the socioeconomic gaps in smoking during recent decades in China. METHODS: We applied growth-curve models to examine inter- and intra-cohort changes in socioeconomic gaps in male smoking in China using data from a national longitudinal survey spanning 25 years. RESULTS: We found diverging trends in smoking in men with different education levels among the post-1980 cohorts; for high-education men, smoking participation consistently declined, but for low-education men, the decline stopped and possibly reversed. The stagnation in the decline in overall smoking rate since 2010 was mostly due to the stalling of the decline of smoking among low-education men in the most recent cohorts. The diverging trends were a continuation of a general trend in expanding educational gaps in smoking that emerged in the cohorts born after 1960. Our analysis also identified widening educational gaps over age within each cohort. CONCLUSION: We identified a long-term widening in educational gaps in smoking in China. An effective way to reduce smoking, social inequality in smoking and possibly health disparities in China is to target the smoking behavior of vulnerable groups.

A Global Trend Analysis of Kidney Cancer Incidence and Mortality and Their Associations with Smoking, Alcohol Consumption, and Metabolic Syndrome.

BACKGROUND: Kidney cancer is a major urological disease globally, with more than 400 000 new cases diagnosed every year. OBJECTIVE: To investigate incidence and mortality trends for kidney cancer and their associations with modifiable risk factors for kidney cancer. DESIGN, SETTING, AND PARTICIPANTS: The most up-to-date figures on kidney cancer incidence and mortality were collected from the GLOBOCAN database and the Cancer Incidence in Five Continents (CI5). Data on total alcohol consumption and the prevalence of smoking, overweight, diabetes, and hypertension were extracted from the World Health Organization Global Health Observatory data repository. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Age-standardized rates (ASRs) for incidence and mortality and their correlations with potential risk factors for kidney cancer were investigated. Multivariable linear regression analysis was also conducted. The 10-yr temporal patterns for incidence are presented as the average annual percent change with 95% confidence interval using joinpoint regression analysis. RESULTS AND LIMITATIONS: Globally, there is wide variation in kidney cancer incidence and mortality. There were positive correlations between rates of smoking, alcohol consumption, and overweight and ASRs of kidney cancer incidence and mortality. Multivariable regression analysis revealed that alcohol consumption and overweight were significant risk factors for kidney cancer incidence, while smoking and alcohol consumption were significant risk factors for kidney cancer mortality. There was an increasing trend for the incidence of kidney cancer globally, with a particularly prominent trend for European countries. Of note, increasing incidence of kidney cancer is evident even for younger individuals aged <50 yr. However, cancer registries vary by country and period and there is a lack of data regarding the severity of risk factors and disease characteristics such as the distribution of histological groups, tumor grading, and staging. CONCLUSIONS: There is an increasing trend for kidney cancer incidence globally, particularly in European countries and the younger population. Modifiable risk factors for kidney cancer incidence and mortality have been identified. The increasing incidence of kidney cancer among younger individuals is worrying and warrants early action on possible preventive measures. PATIENT SUMMARY: The incidence of kidney cancer has been increasing globally, particularly in European countries and the younger population. Risk factors include smoking, alcohol consumption, overweight, and hypertension, and these factors are all modifiable.

Prevalence and Influencing Factors of Metabolic Syndrome among Adults in China from 2015 to 2017.

The prevalence and influencing factors of metabolic syndrome (MetS) in Chinese residents aged 20 or older were investigated. The data were collected from China Nutrition and Health Surveillance (2015-2017), which used a stratified, multistage, random sampling method. A total of 130,018 residents aged 20 years or older from 31 provinces were included in this study. The National Cholesterol Education Programme Adult Treatment Panel III (NCEP ATP III) criteria were used to define MetS. The standardised prevalence of high waist circumference, high blood pressure and low high-density lipoprotein cholesterol were 40.8%, 49.4% and 41.1%, respectively. The following factors were associated with a higher prevalence of MetS: female [odds ratio (OR) = 1.773, 95% CI = 1.709-1.840]; older age (OR = 1.037, 95% CI = 1.036-1.039); living in north China (OR = 1.087, 95% CI = 1.058-1.117); high body mass index (OR = 1.402, 95% CI = 1.395-1.408); higher income [OR (95% CI): 1.044 (1.007-1.083), 1.083 (1.044-1.124) and 1.123 (1.078-1.170) for moderate, high, and very high income, respectively]; family history of hypertension (OR = 1.237, 95% CI = 1.203-1.273); family history of diabetes (OR = 1.491, 95% CI = 1.426-1.558) and current smoking status (OR = 1.143, 95% CI = 1.098-1.191). Living in the countryside (OR = 0.960, 95% CI = 0.932-0.988), moderate alcohol consumption (OR = 0.917, 95% CI = 0.889-0.946) and being physically active (OR = 0.887, 95% CI = 0.862-0.913) were associated with a lower prevalence of MetS. The prevalence of MetS among residents aged 20 years or older in China is increasing, especially among women, people aged 45 years or older and urban residents. Preventive efforts, such as quitting smoking and engaging in physical activity, are recommended to reduce the risk of MetS.

Comparison of Respiratory Health Impacts Associated with Wood and Charcoal Biomass Fuels: A Population-Based Analysis of 475,000 Children from 30 Low- and Middle-Income Countries.

BACKGROUND: The World Health Organisation reported that 45% of global acute respiratory infection (ARI) deaths in children under five years are attributable to household air pollution, which has been recognised to be strongly associated with solid biomass fuel usage in domestic settings. The introduction of legislative restrictions for charcoal production or purchase can result in unintended consequences, such as reversion to more polluting biomass fuels such as wood; which may increase health and environmental harms. However, there remains a paucity of evidence concerning the relative health risks between wood and charcoal. This study compares the risk of respiratory symptoms, ARI, and severe ARI among children aged under five years living in wood and charcoal fuel households across 30 low- and middle-income countries. METHODS: Data from children (N = 475,089) residing in wood or charcoal cooking households were extracted from multiple population-based Demographic and Health Survey databases (DHS) (N = 30 countries). Outcome measures were obtained from a maternal report of respiratory symptoms (cough, shortness of breath and fever) occurring in the two weeks prior to the survey date, generating a composite measure of ARI (cough and shortness of breath) and severe ARI (cough, shortness of breath and fever). Multivariable logistic regression analyses were implemented, with adjustment at individual, household, regional and country level for relevant demographic, social, and health-related confounding factors. RESULTS: Increased odds ratios of fever (AOR: 1.07; 95% CI: 1.02-1.12) were observed among children living in wood cooking households compared to the use of charcoal. However, no association was observed with shortness of breath (AOR: 1.03; 95% CI: 0.96-1.10), cough (AOR: 0.99; 95% CI: 0.95-1.04), ARI (AOR: 1.03; 95% CI: 0.96-1.11) or severe ARI (AOR: 1.07; 95% CI: 0.99-1.17). Within rural areas, only shortness of breath was observed to be associated with wood cooking (AOR: 1.08; 95% CI: 1.01-1.15). However, an increased odds ratio of ARI was observed in Asian (AOR: 1.25; 95% CI: 1.04-1.51) and East African countries (AOR: 1.11; 95% CI: 1.01-1.22) only. CONCLUSION: Our population-based observational data indicates that in Asia and East Africa there is a greater risk of ARI among children aged under 5 years living in wood compared to charcoal cooking households. These findings have major implications for understanding the existing health impacts of wood-based biomass fuel usage and may be of relevance to settings where charcoal fuel restrictions are under consideration.

Disease Burden, Risk Factors, and Recent Trends of Liver Cancer: A Global Country-Level Analysis.

BACKGROUND: This study aimed to evaluate the updated disease burden, risk factors, and temporal trends of liver cancer based on age, sex, and country. METHODS: We estimated the incidence of liver cancer and its attribution to hepatitis B virus (HBV) and hepatitis C virus (HCV) in 2018 based on the Global Cancer Observatory and World Health Organization (WHO) Cancer Causes database. We extracted the prevalence of risk factors from the WHO Global Health Observatory to examine the associations by weighted linear regression. The trend analysis used data from the Cancer Incidence in Five Continents and the WHO mortality database from 48 countries. Temporal patterns of incidence and mortality were calculated using average annual percent change (AAPC) by joinpoint regression analysis. RESULTS: The global incidence of liver cancer was (age-standardized rate [ASR]) 9.3 per 100,000 population in 2018, and there was an evident disparity in the incidence related to HBV (ASR 0.2-41.2) and HCV (ASR 0.4-43.5). A higher HCV/HBV-related incidence ratio was associated with a higher level of alcohol consumption (ß 0.49), overweight (ß 0.51), obesity (ß 0.64), elevated cholesterol (ß 0.70), gross domestic product (ß 0.20), and Human Development Index (HDI; ß 0.45). An increasing trend in incidence was identified in many countries, especially for male individuals, population aged ≥50 years, and countries with a higher HCV/HBV-related liver cancer incidence ratio. Countries with the most drastic increase in male incidence were reported in India (AAPC 7.70), Ireland (AAPC 5.60), Sweden (AAPC 5.72), the UK (AAPC 5.59), and Norway (AAPC 4.87). CONCLUSION: We observed an overall increasing trend of liver cancer, especially among male subjects, older individuals, and countries with a higher prevalence of HCV-related liver cancer. More efforts are needed in enhancing lifestyle modifications and accessibility of antiviral treatment for these populations. Future studies should investigate the reasons behind these epidemiological changes.

Regional Differences in the Prevalence of Anaemia and Associated Risk Factors among Infants Aged 0-23 Months in China: China Nutrition and Health Surveillance.

Infantile anaemia has been a severe public health problem in China for decades. However, it is unclear whether there are regional differences in the prevalence of anaemia. In this study, we used data from the China Nutrition and Health Surveillance (CNHS) to assess the prevalence of anaemia and the risk factors associated with its prevalence in different regions. We included 9596 infants aged 0-23 months from the CNHS 2013 database. An infant was diagnosed with anaemia if he/she had a haemoglobin concentration of <110 g/L. We used multivariate logistic regression to investigate the potential risk factors associated with the development of anaemia. We found that anaemia was present in 2126 (22.15%) of the infants assessed. Approximately 95% of these cases were classified as mild anaemia. Based on the guidelines laid out by the World Health Organization, 5.5% and 43.6% of the surveillance sites were categorized as having severe and moderate epidemic levels of anaemia, respectively. The prevalence of infantile anaemia in Eastern, Central and Western China was 16.67%, 22.25% and 27.44%, respectively. Premature birth, low birth weight, breastfeeding and residence in Western China were significantly associated with higher odds of developing anaemia. Female sex and having mothers with high levels of education and maternal birth age >25 years were associated with lower odds of developing anaemia. In conclusion, we observed significant regional disparities in the prevalence of infantile anaemia in China. Western China had the highest prevalence of infantile anaemia, and rural regions showed a higher prevalence of anaemia than urban regions.

Global incidence and mortality of breast cancer: a trend analysis.

This study aimed to evaluate the global incidence and mortality trends of breast cancer among females by region and age in the past decade. We retrieved country-specific incidence and mortality data from the Global Cancer Observatory up to 2018 and Cancer Incidence in Five Continents volumes I-XI, the Nordic Cancer Registries, the Surveillance, Epidemiology, and End Results, and WHO mortality database up to 2016. The temporal patterns were using Average Annual Percent Change (AAPC) with the 95% confidence interval (CI) by joinpoint regression analysis. Most countries showed an increasing trend in incidence. For the older population aged ≥ 50 years, Japan (5.63, 4.90-6.36), Slovakia (3.63, 3.03-4.22), China (2.86, 2.00-3.72) reported the most prominent increase. For young females (<50 years), Japan (AAPC=3.81, 95% CI=2.71-4.93), Germany (AAPC=2.60, 95% CI=1.41-3.81) and Slovakia (1.91, 1.13-2.69) reported the most drastic rise. Similarly, 12 countries showed an incidence increase among women aged <40 years. As for mortality, the Philippines (4.36, 3.65-5.07), Thailand (4.35, 3.12-5.59), Colombia (0.75, 0.08-1.42), and Brazil (0.44, 0.19-0.68) reported a significant increase. The disease burden of breast cancer showed an increasing trend in a large number of populations. More preventive efforts are recommended for these countries. Further research should explore the underlying reasons for these epidemiological trends.

Global Burden, Risk Factors, and Trends of Esophageal Cancer: An Analysis of Cancer Registries from 48 Countries.

This study aimed to examine the global burden, risk factors, and trends of esophageal cancer based on age, sex, and histological subtype. The data were retrieved from cancer registries database from 48 countries in the period 1980-2017. Temporal patterns of incidence and mortality were evaluated by average annual percent change (AAPC) using joinpoint regression. Associations with risk factors were examined by linear regression. The highest incidence of esophageal cancer was observed in Eastern Asia. The highest incidence of adenocarcinoma (AC) was found in the Netherlands, the United Kingdom, and Ireland. A higher AC/squamous cell carcinoma (SCC) incidence ratio was associated with a higher prevalence of obesity and elevated cholesterol. We observed an incidence increase (including AC and SCC) in some countries, with the Czech Republic (female: AAPC 4.66), Spain (female: 3.41), Norway (male: 3.10), Japan (female: 2.18), Thailand (male: 2.17), the Netherlands (male: 2.11; female: 1.88), and Canada (male: 1.51) showing the most significant increase. Countries with increasing mortality included Thailand (male: 5.24), Austria (female: 3.67), Latvia (male: 2.33), and Portugal (male: 1.12). Although the incidence of esophageal cancer showed an overall decreasing trend, an increasing trend was observed in some countries with high AC/SCC incidence ratios. More preventive measures are needed for these countries.

Spatiotemporal mapping and assessment of daily ground NO2 concentrations in China using high-resolution TROPOMI retrievals.

Nitrogen dioxide (NO2) is an important air pollutant that causes direct harms to the environment and human health. Ground NO2 mapping with high spatiotemporal resolution is critical for fine-scale air pollution and environmental health research. We thus developed a spatiotemporal regression kriging model to map daily high-resolution (3-km) ground NO2 concentrations in China using the Tropospheric Monitoring Instrument (TROPOMI) satellite retrievals and geographical covariates. This model combined geographically and temporally weighted regression with spatiotemporal kriging and achieved robust prediction performance with sample-based and site-based cross-validation R2 values of 0.84 and 0.79. The annual mean and standard deviation of ground NO2 concentrations from June 1, 2018 to May 31, 2019 were predicted to be 15.05 ± 7.82 µg/m3, with that in 0.6% of China's area (10% of the population) exceeding the annual air quality standard (40 µg/m3). The ground NO2 concentrations during the coronavirus disease (COVID-19) period (January and February in 2020) was 14% lower than that during the same period in 2019 and the mean population exposure to ground NO2 was reduced by 25%. This study was the first to use TROPOMI retrievals to map fine-scale daily ground NO2 concentrations across all of China. This was also an early application to use the satellite-estimated ground NO2 data to quantify the impact of the COVID-19 pandemic on the air pollution and population exposures. These newly satellite-derived ground NO2 data with high spatiotemporal resolution have value in advancing environmental and health research in China.

Indoor Exposure to Ambient Particles and Its Estimation Using Fixed Site Monitors.

Ambient PM2.5 concentrations measured at fixed site monitors (FSM) are often biased with respect to exposure concentrations because of spatial variability and infiltration. Based on comparison of ambient concentrations from 14 FSMs and of exposure concentrations measured indoors and outdoors at two schools in Hong Kong for winter and summer seasons, the magnitude and sources of exposure error based on using FSMs as a surrogate for exposure are quantified. An approach for bias correcting surrogate exposure estimates from FSMs is demonstrated. The approach is based on a proximity factor (PF) that accounts for differences in spatial locations, proximity to emissions and deviation from dominant wind direction, and an infiltration factor (IF) that varies by season. The combination of the PF and IF reduce bias in mean school exposure estimates from ±90% to ±20%. Bias in exposure estimates from using FSMs as surrogates tend to be smaller for which the exposure site and FSM are aligned with wind direction, have similar sampling height, and are in close proximity. The methodology demonstrated to assess concordance between FSMs and exposure measurement sites can be applied more broadly to help reduce exposure error, which may help to interpret seasonal variations in health estimates.

Association between whole grain intake and breast cancer risk: a systematic review and meta-analysis of observational studies.

BACKGROUND: Epidemiological studies have found that high whole grain intake may be associated with a reduced risk of breast cancer. However, the evidence has not been consistent. We conducted a meta-analysis to quantitatively assess the association between whole grain intake and breast cancer risk. METHODS: Relevant observational studies were identified by searching PubMed, Embase, Cochrane library databases, and Google Scholar through April 2017. Summary relative risk (RR) estimates were calculated using random-effects meta-analysis. RESULTS: A total of 11 studies, including 4 cohort and 7 case-control studies and involving 131,151 participants and 11,589 breast cancer cases, were included in the current meta-analysis. The pooled RR of breast cancer for those with high versus low whole grain intake was 0.84 (95% confidence interval [CI]: 0.74 to 0.96, p = 0.009; I2 = 63.8%, p for heterogeneity = 0.002). Subgroup analysis by study design found a significant inverse association in the case-control studies (RR: 0.69; 95% CI: 0.56 to 0.87, p = 0.001; I2 = 58.2%, p for heterogeneity = 0.026), but not in the cohort studies (RR, 0.96; 95% CI: 0.82 to 1.14, p = 0.69; I2 = 66.7%, p for heterogeneity = 0.029). In addition, stratified analysis suggested that sample size could be a potential source of heterogeneity. CONCLUSIONS: Results of the current meta-analysis suggest that high intake of whole grains might be inversely associated with a reduced risk of breast cancer, and the inverse association was only observed in case-control but not cohort studies. More large-scale cohort studies are needed to confirm the inverse association observed.

Dietary patterns and the risk of esophageal squamous cell carcinoma: A population-based case-control study in a rural population.

BACKGROUND & AIMS: Few studies were available in exploring the roles of dietary patterns in the development of esophageal cancer, especially in China. This study aimed to investigate the roles of dietary patterns in the risk of esophageal squamous cell carcinoma (ESCC) in a Chinese rural population. METHODS: A population-based cases-control study was designed and conducted in Yanting County, Sichuan Province of China during two years (between June 2011 and May 2013). A total of 942 pairs of ESCC cases and controls were recruited. A food frequency questionnaire was adopted to collect information of dietary consumption. Dietary patterns were extracted by using principle component and factor analysis based on 24 dietary groups. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated by using logistic regression model, with adjustment for possible confounding variables. RESULTS: Four major dietary patterns were identified, which were labeled as "prudent", "vegetable and fruits", "processed food" and "alcohol drinking". In comparison of the highest with the lowest quartiles of pattern scores, the processed food pattern (OR: 2.84, 95% CI: 2.13-3.80) and alcohol drinking pattern (OR: 2.69, 95% CI: 1.95-3.71) were significantly associated with an increased risk of ESCC, while the vegetable and fruit pattern (OR: 0.70, 95% CI: 0.53-0.92) was associated with reduced risk by 30%. The prudent pattern was associated with a reduced risk by 33% (OR: 0.67, 95% CI: 0.50-0.88) in a multivariate logistic regression model, but no statistical significance was reached in a composite model. CONCLUSIONS: The results suggest an important role of dietary patterns in ESCC. Diets rich in vegetables and fruits may decrease the risk of ESCC, whereas diets rich in processed food and drinking alcohol may increase the risk.

Randomised controlled trial of effect of whole soy replacement diet on features of metabolic syndrome in postmenopausal women: study protocol.

INTRODUCTION: Metabolic syndrome (MetS) is a public health problem in postmenopausal women. Whole soy foods are rich in unsaturated fats, high quality plant protein and various bioactive phytochemicals that may have a beneficial role in the management of MetS. The aim of the study is to examine the effect of whole soy replacement diet on the features of MetS among postmenopausal women. METHODS AND ANALYSIS: This will be a 12-month, randomised, single-blind, parallel controlled trial among 208 postmenopausal women at risk of MetS or with early MetS. After 4 weeks' run-in, subjects will be randomly allocated to one of two intervention groups, whole soy replacement group or control group, each for 12 months. Subjects in the whole soy group will be required to include four servings of whole soy foods (containing 25 g soy protein) into their daily diet iso-calorically, replacing red or processed meat and high fat dairy products. Subjects in the control group will remain on a usual diet. The outcome measures will include metabolic parameters as well as a 10-year risk for ischaemic cardiovascular disease. We hypothesise that the whole soy substitution diet will notably improve features of MetS in postmenopausal women at risk of MetS or with early MetS. The study will have both theoretical and practical significance. If proven effective, the application of the whole soy replacement diet model will be a safe, practical and economical strategy for MetS prevention and treatment. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the Ethics Committee of the Chinese University of Hong Kong. The results will be disseminated via conference presentations and papers in academic peer reviewed journals. Data files will be deposited in an accessible repository. TRIAL REGISTRATION NUMBER: NCT02610322.

Reproducibility and Validity of a Food Frequency Questionnaire for Assessing Dietary Consumption via the Dietary Pattern Method in a Chinese Rural Population.

OBJECTIVE: This study was conducted to assess the reproducibility and validity of a food frequency questionnaire (FFQ) that was developed to assess the overall dietary consumption via dietary pattern method in a rural population in southwest China. METHODS: A total of 179 participants aged between 40 and 70 years old were included in this study. Participants administered FFQ at baseline (FFQ1) and one year later (FFQ2) to assess the reproducibility. Six 3-day 24-hour recalls (24HRs) were completed between the administrations of two FFQs to determine the validity. Dietary patterns from three separate dietary sources were derived by using principle component factor analysis. Comparisons between dietary pattern scores were made by using Pearson or intraclass correlation coefficient, cross-classification analysis, weighted kappa (κ) statistic and Bland-Altman analysis. The de-attenuated method was adopted to correct the monthly and seasonally variation and the partial correlation analysis was used correct the influence by total energy intake. RESULTS: Two major dietary factors, labeled as prudent pattern and processed food pattern, were identified. The prudent pattern was characterized by higher factor loadings of wheat, rice, fresh vegetables, bean products, nuts, red meat, white meat and fresh eggs; and the processed food pattern was characterized by higher factor loadings of pickled vegetables, preserved vegetables and salted meat. Between Two FFQs, intraclass correlation coefficients were 0.57 for prudent pattern and 0.55 for processed food pattern, partial Pearson correlation coefficients were 0.51 for the prudent pattern and 0.56 for the processed food pattern; weighted κ statistic ranged from 0.45 (for the prudent pattern) to 0.56 (for the processed food pattern). Between FFQs and 24HRs, de-attenuated correlation coefficients ranged from 0.54 to 0.78 for the prudent pattern and from 0.55 to 0.61 for the processed food pattern; partial Pearson correlation coefficients ranged from 0.41 to 0.56 for the prudent pattern and from 0.42 to 0.44 for the processed food pattern; weighted κ statistic ranged from 0.42 to 0.46 for prudent pattern and from 0.43 to 0.60 for processed food pattern. The Bland-Altman plots and limits of agreement indicated that the deviation/divergence was not obvious for both of the patterns between FFQ1 and FFQ2 and between FFQs and 24HRs. CONCLUSION: The study suggests that the FFQ is reasonably reproducible and valid to assess the overall dietary consumption via dietary pattern methods in the Chinese rural population.