Associations of PM2.5 composition and green space with metabolic syndrome in a Chinese essential hypertensive population.

BACKGROUND: Metabolic syndrome (MetS) has emerged as a significant global public health concern. While environmental factors, including PM2.5, have been identified as important risk factors for MetS in the general population, limited studies have investigated their impact on individuals with essential hypertension. Therefore, our study aims to explore the relationship between PM2.5 composition, green space, and their combined effects on MetS among a Chinese essential hypertensive population. METHOD: A total of 20,131 participants diagnosed with essential hypertension from 10 provinces in China were included in this study. Individual level exposure to various environmental factors (including PM2.5, PM2.5 composition, green space and temperature) were evaluated using spatiotemporal models based on satellites data. Participants were defined as MetS according to the definition issued by the International Diabetes Federation. Generalized additive mixed models were used to analyze the individual air pollutants, green space and their interaction on MetS. RESULT: The prevalence of MetS in this population was 44.33%. The adjusted odd ratio (OR) of MetS, with each one unit increase in SO42-, BC and NO3- were 1.077 (1.049, 1.106), 1.126 (1.077, 1.177) and 0.977 (0.958, 0.996) respectively. Additionally, each unit increase of the Normalized Difference Vegetation Index (NDVI) was associated with a decreased risk of MetS (OR: 0.988, 95% CI: 0.984-0.993). In particular, green space was found to mitigate the adverse impacts of PM2.5 on MetS (OR: 0.988, 95% CI: 0.984-0.993). CONCLUSION: Our results suggested that there was a positive association between PM2.5 and its composition (SO42-, BC) with MetS in the essential hypertensive population, while green space might play a protective role. Moreover, green space could effectively weaken the positive relationship between air pollutants and MetS, especially in males and participants younger than 60 years old.

The association between endocrine disrupting chemicals and MAFLD: Evidence from NHANES survey.

Previous studies on the association of endocrine-disrupting chemicals (EDCs) with metabolic dysfunction-associated fatty liver disease (MAFLD) are very limited. This study analyzed the association of EDCs exposure with MAFLD among 5073 American adults from the 2017-2018 National Health and Nutrition Examination Survey. The results showed that increased exposure to 3 EDCs metabolites (namely As, DiNP and PFOA) were significantly associated with MAFLD, the odds ratio of which were 1.819 (95% CI: 1.224, 2.702), 1.959 (95% CI: 1.224, 3.136) and 2.148 (95% CI: 1.036, 4.456), respectively. Further, the bayesian kernel machine regression model also revealed that phthalates exposure was strongly connected with the MAFLD, particularly in females and the elderly over 65. Moderating effect analysis suggested that higher body mass index (BMI) and inflammatory diet habit (indicated by dietary inflammatory index) strengthened the association between EDCs and MAFLD, whereas population with higher level of insulin sensitivity showed lower risk. In conclusion, our results suggest that either single or combined exposure to EDCs metabolites is link to MAFLD. Our findings also encourage people to sustain a healthy diet, normal levels of insulin sensitivity and BMI, which may help to alleviate the association of MAFLD risk in exposure to EDCs. These results also help us to better understand the association of EDCs and MAFLD and provide effective evidences for preventing MAFLD from the EDCs exposure aspect.

The Interactive Effects between Drought and Air Pollutants on Children's Upper Respiratory Tract Infection: A Time-Series Analysis in Gansu, China.

As a destructive and economic disaster in the world, drought shows an increasing trend under the continuous global climate change and adverse health effects have been reported. The interactive effects between drought and air pollutants, which may also be harmful to respiratory systems, remain to be discussed. We built the generalized additive model (GAM) and distributed lag nonlinear model (DLNM) to estimate the effects of drought and air pollutants on daily upper respiratory infections (URTI) outpatient visits among children under 6 in three cities of Gansu province. The Standardized Precipitation Index (SPI) based on monthly precipitation (SPI-1) was used as an indicator of drought. A non-stratified model was established to explore the interaction effect of SPI-1 and air pollutants. We illustrated the number of daily pediatric URTI outpatient visits increased with the decrease in SPI-1. The interactive effects between air pollutants and the number of daily pediatric URTIs were significant. According to the non-stratified model, we revealed highly polluted and drought environments had the most significant impact on URTI in children. The occurrence of drought and air pollutants increased URTI in children and exhibited a significant interactive effect.

Seasonal characteristics of ambient temperature variation (DTR, TCN, and TV0-t) and air pollutants on childhood asthma attack in a dry and cold city in China.

Very few researches have concentrated on a variety of time scales to evaluate the association between temperature variation (TV) and childhood asthma (CA), and the evidence for the interaction of air pollutants on this association is lacking. In this study, we aim to estimate the relative risks (RRs) of CA due to TV by following metrics: diurnal temperature range (DTR), temperature changes between neighboring days (TCN), and temperature variability (TV0-t); to quantify the seasonal attributable fraction (AF) and number (AN) of CA due to TV; to examine the interactive effects of the TV and air pollutants on CA in different seasons. We mainly applied distributed lagged nonlinear model (DLNM) and conditional Poisson models to evaluate the associations between TV and outpatient visits for CA during 2014-2019 in Lanzhou, China. Additionally, the bivariate response surface model was used to examine the interplay effect of air pollutants. We found that in warm season, the risks of DTR maximum at lag5 (RR = 1.073, 95% CI: 1.017-1.133); TCN showed protective effect. In cold season, the risks of DTR peaked at lag8 (RR = 1.063, 95% CI: 1.027-1.100); the risks of TCN maximum at lag0 (RR = 1.058 95% CI: 1.009-1.109); the estimation of total cases maximized at TV0-4 in cold season (RR = 1.039 at TV0-3, 95% CI: 1.001, 1.077) and was the lowest at TV0-1 in warm season (RR = 0.999, 95% CI: 0.969, 1.030). In addition, the response surface model graphically pictured ambient air pollutants enhanced the DTR/TV0-4-CA effect for girls. In conclusion, the RRs of CA are markedly increased by TV exposure, particularly during the colder months. A combined evaluation of DTR, TCN, TV0-5∼TV0-6, NO2, SO2, and PM2.5 should be used to identify the adverse effects of TV on CA.

Impact of high temperature on road injury mortality in a changing climate, 1990-2019: A global analysis.

BACKGROUND: Previous studies have shown that extreme heat likely increases the risk of road injuries. However, the global burden of road injuries due to high temperature and contributing factors remain unclear. This study aims to characterize the global, regional and national burden of road injuries due to high temperature from 1990 to 2019. METHODS: Based on the Global Burden of Disease (GBD) study 2019, we obtained the numbers and age-standardized mortality rates (ASMR) and age-standardized disability-adjusted life years (DALY) rates (ASDR) of the road injury due to high temperature at global, regional, and national levels from 1990 to 2019. The world is divided into five climate zones according to the average annual temperature of each country: tropical, subtropical, warm temperate, cold temperate, and boreal. We used the generalized additive models (GAM) to model the trends of road injuries globally and by region. RESULTS: Globally, between 1990 and 2019, the deaths of road injury attributable to high temperature increased significantly from 20,270 (95% uncertainty interval [UI], 7836 to 42,716) to 28,396 (95% UI, 13,311 to 51,178), and the DALYs increased from 1,169,309 (95% UI, 450,834 to 2,491,075) to 1,414,527 (95% UI, 658,347 to 2,543,613). But the ASMR and the ASDR slightly decreased by 8.49% and 13.16%, respectively. The burden of road injury death attributable to high temperature remained high in low SDI and tropical regions. In addition, road transport infrastructure investment per inhabitant is associated with the burden of road injuries attributable to high temperature. CONCLUSIONS: Globally, the ASMR and ASDR for road injuries attributable to high temperature decreased from 1990 to 2019, but the absolute death and DALYs continued to increase. Thus, concerning global warming, implementation of prevention and interventions to reduce road injuries from heat exposure should be stressed globally.

Perchlorate, nitrate, and thiocyanate and depression: the potential mediating role of sleep.

Perchlorate, nitrate, and thiocyanate are common thyroid disruptors, but it is not clear whether they are related to depression. In this study, we aimed to investigate the association between perchlorate, nitrate, and thiocyanate and depression, and to explore the potential role of sleep in this process. We used data from the National Health and Nutrition Examination Survey (NHANES). From 2005 to 2016, 6 cycles cross-sectional data were combined. Urinary perchlorate, nitrate, and thiocyanate came from laboratory test; depression was diagnosed by the Nine-item Patient Health Questionnaire (PHQ-9). Weighted generalized liner models, restricted cubic splines, and mediation analysis were used in this study. Totally, 16,715 participants were involved in this study, of which 8295 (49.63%) were male and 8420 (50.37%) were female, with an average age of 46.19 ± 0.32 years. We found that urinary thiocyanate concentration was positively associated with depression (Odds ratios [ORs]: 1.49; 95% confidence intervals [95% CIs]: 1.16, 1.91), but not perchlorate (ORs: 0.71; 95% CIs: 0.52, 0.97) or nitrate (ORs: 0.89, 95% CIs: 0.66, 1.19). Sleep may play a potential mediating role between thiocyanate and depression (9.55%). In conclusion, higher concentrations of thiocyanate exposure may be associated with a higher risk of depression, and the sleep duration may be an important mediating factor.

A global burden assessment of lung cancer attributed to residential radon exposure during 1990-2019.

This study aimed to explore the spatial and temporal trends of lung cancer burden attributable to residential radon exposure at the global, regional, and national levels. Based on the Global Burden of Disease Study (GBD) 2019, we collected the age-standardized mortality rate (ASMR) and age-standardized disability-adjusted life rate (ASDR) of lung cancer attributable to residential radon exposure from 1990 to 2019. The Joinpoint model was used to calculate the annual average percentage change (AAPC) to evaluate the trend of ASMR and ASDR from 1990 to 2019. The locally weighted regression (LOESS) was used to estimate the relationship of the socio-demographic index (SDI) with ASMR and ASDR. In 2019, the global ASMR and ASDR for lung cancer attributable to residential radon exposure were 1.03 (95% CI: 0.20, 2.00) and 22.66 (95% CI: 4.49, 43.94) per 100 000 population, which were 15.6% and 23.0% lower than in 1990, respectively. According to the estimation, we found the lung cancer burden attributable to residential radon exposure declined significantly in high and high-middle SDI regions, but substantially increased in middle and low-middle SDI regions from 1990 to 2019. Across age and sex, the highest burden of lung cancer attributable to residential radon exposure was found in males and elderly groups. In conclusion, the global burden of lung cancer attributable to residential radon exposure showed a declining trend from 1990 to 2019, but a relatively large increase was found in the middle SDI regions. In 2019, the burden of lung cancer attributable to residential radon exposure remained high, particularly in males, the elderly, and high-middle SDI regions compared with other groups.

Effects of long-term exposure to PM2.5 and chemical constituents on blood lipids in an essential hypertensive population: A multi-city study in China.

Previous studies on the effects of fine particulate matter (PM2.5) and chemical constituents on lipid disorder among hypertension populations, particularly in China, are very limited. We aimed to examine the effects of long-term exposure to PM2.5 and chemical constituents on dyslipidemias in China. Finally, we included 34,841 participants with essential hypertension from 19 regions in China during 2010-2011. Data were modeled using the generalized additive mixed model. We found that PM2.5 and chemical constituents exposure were positively associated with the increased risk of dyslipidemias and increased levels of total cholesterol (TC) and triglyceride (TG). The odds ratio for hypercholesterolemia was 1.356 [95% confidence interval (CI): 1.246, 1.477] for PM2.5, and the strongest association with PM2.5 constituents was found for nitrate. Each 10 µg/m3 increase in PM2.5 showed a significant increase of TC by 2.60% (95% CI: 2.03, 3.17) and TG by 2.91% (95% CI: 1.60, 4.24), respectively. Meanwhile, an interquartile range increase in nitrate, ammonium and organic matter had stronger associations with TC and TG parameters than black carbon, sulfate, and mineral dust. Our findings may contribute to a better understanding of the chronic effects of PM2.5 and chemical constituents on lipid disorder in an essential hypertensive population.

Cold exposure, gut microbiota, and hypertension: A mechanistic study.

Cold exposure has been recognized as an important risk factor for hypertension, and altered gut microbiota has been reported to be associated with hypertension. We hypothesized that there is a plausible relationship between gut microbiota and cold-induced hypertension (CIH). Therefore, we explored the potential link between the gut microbiota and its metabolites with CIH. Male Sprague-Dawley (SD) rats were randomly divided into the normal temperature group (NT, 20 ± 2 °C) and the cold exposure group (CE, 4 ± 1 °C), and faecal bacteria cross-transplantation was performed after six weeks. We analyzed the gut microbiota of rats using the 16S rDNA sequence and measured the blood pressure of rats and the content of short-chain fatty acids in rat faeces. After six weeks of cold exposure, the CIH rat model was successfully established. The cold exposure reduced the diversity of the gut microbiota, increased the abundance of potentially pathogenic and conditionally pathogenic bacteria (e.g., Quinella, Rothia, and Senegalimassilia genera), and reduced the abundance of beneficial bacteria (e.g., Lactobacillus genus) and butyric acid-producing bacteria (e.g., Lachnospiraceae UCG-008 and Ruminococcaceae UCG-013 genera). Faecal bacteria cross-transplantation altered gut microbiota composition and regulated blood pressure levels. The NT group rats transplanted with CIH rats' faecal bacteria were enriched with certain conditional pathogenic bacteria such as Prevotellaceae UCG-003 genus. The CIH rats transplanted with faecal bacteria from the NT group rats were enriched with beneficial bacteria such as Bacteroides genus. In addition, we found a significant reduction in butyric acid levels in CIH rats, which may be related to the increase in blood pressure. In conclusion, CIH is associated with altered gut microbiota and reduced butyric acid. Our findings provide novel insights for the prevention and treatment of CIH by modulating the gut microbiota through supplementation of beneficial bacteria/butyrate.

Impact of high, low, and non-optimum temperatures on chronic kidney disease in a changing climate, 1990-2019: A global analysis.

BACKGROUND: Although a few studies have reported the relationship between high and low temperatures and chronic kidney disease (CKD), the global burden of CKD attributable to extreme heat and cold in recent decades remains unknown. METHODS: Based on the Global Burden of Disease Study (GBD) 2019, we obtained data on age-standardized mortality rates (ASMR) and age-standardized rates of disability-adjusted life years (ASDR) per 100 000 population of the CKD attributable to non-optimum temperatures from 1990 to 2019. The annual mean temperature of each country was used to divide each country into five climate zones (tropical, subtropical, warm-temperate, cool-temperate, and boreal). The locally weighted regression model was used to estimate the burden for different climate zones and Socio-demographic index (SDI) regions. RESULTS: In 1990, the ASMR and ASDR due to high temperature estimated -0.01 (95% UI, -0.74 to 0.44) and -0.32 (-21.66 to 12.66) per 100 000 population, respectively. In 2019, the ASMR and ASDR reached 0.10 (-0.28 to 0.38) and 2.71 (-8.07 to 10.46), respectively. The high-temperature burden increased most rapidly in tropical and low SDI regions. There were 0.99 (0.59 to 1.39) ASMR attributable to low-temperature in 1990, which increased to 1.05 (0.61-1.49) in 2019. While the ASDR due to low temperature declined from 22.03 (12.66 to 30.64) in 1990 to 20.43 (11.30 to 29.26) in 2019. Overall, the burden of CKD attributable to non-optimal temperatures has increased from 1990 to 2019. CKD due to hypertension and diabetes mellitus were the primary causes of CKD death attributable to non-optimum temperatures in 2019 with males and older adults being more susceptible to these temperatures. CONCLUSIONS: The CKD burden due to high, low, and non-optimum temperatures varies considerably by regions and countries. The burden of CKD attributable to high temperature has been increasing since 1990.

Physical activity reduces the role of blood cadmium on depression: A cross-sectional analysis with NHANES data.

Cadmium (Cd) exposure is recognized as an important risk factor for psychological health, but suitable physical activity may relieve depression. However, it remains unknown whether physical activity (PA) can reduce the effect of cadmium exposure on depression. Therefore, a cross-sectional data from National Health and Nutrition Examination Survey (NHANES) 2015-2018 was used. The Nine-item Patient Health Questionnaire (PHQ-9) was used to assess depression among the participants. PA was calculated according to the metabolic equivalent (MET), weekly frequency, and duration of each activity. Logistic regression and restricted cubic spline models were used to examine the associations of Cd and depression. A total of 5560 adults aged 20 years and above were finally included in this study. The results indicated a positive correlation between blood Cd and depression. The multivariate-adjusted ORs (95% CI) of the highest quartile were 2.290 (1.754-2.990) for depression, which was still significant after controlling other heavy metals (P < 0.05). Under Cd exposure, the high intensity of physical activity group had the lowest risk of depression (OR = 2.226, 95%CI: 1.447-3.425), while the group with no physical activity had the highest risk (OR = 2.443, 95%CI: 1.382-4.318). Our results indicate that inner Cd exposure may be a risk factor for depression, and physical activity can moderate this relationship to some degree.

Indoor solid fuel use and renal function among middle-aged and older adults: A national study in rural China.

Solid fuel use is the main source of indoor air pollution, especially in rural areas of developing countries. Nevertheless, the evidence linking indoor solid fuel use and renal function is very limited. Therefore, we investigated the association between indoor solid fuel use and renal function among middle-aged and older adults in rural China. Cystatin C (CysC) concentration of each participant was used to calculate the estimated glomerular filtration rate (eGFR). We used the baseline data to investigate the associations between solid fuel use for cooking and heating and eGFR through a linear-mixed effects model. Then, we applied the generalized linear-mixed effects model with binary distribution to examine the relationship between renal function decline and cooking fuel switching from 2011 to 2015. A total of 4959 participants were included at baseline, and 3536 participants were included in the follow-up analysis. Compared to participants who used clean fuel for both cooking and heating, the eGFR was significantly lower among participants who cooked with solid fuel and heated with clean fuel (ß: -2.81; 95% CI: -5.53, -0.09). In the follow-up analysis, the risks of renal function decline for participants using solid fuel for cooking were significantly higher in males (OR: 2.74; 95% CI: 1.68, 4.49), smokers (OR: 5.70; 95% CI: 2.82, 11.55), and drinkers (OR: 7.11; 95% CI: 3.15, 16.02) compared to females, non-smokers, and non-drinkers. Moreover, 45-65 years aged participants (OR: 0.54; 95% CI: 0.33, 0.89) and non-drinkers (OR: 0.61; 95% CI: 0.41, 0.92) who switched from solid to clean cooking fuel had a lower risk of renal function decline. In conclusion, our findings show that household solid fuel use is likely to be an important risk factor for renal function decline in rural China. And switching to cleaner fuel may provide significant public health benefits.