Is prehypertension more strongly associated with long-term ambient air pollution exposure than hypertension? Findings from the 33 Communities Chinese Health Study

Ozone exposure and cardiovascular disease: A narrative review of epidemiology evidence and underlying mechanisms

Ozone (O3) poses a significant global public health concern as it exerts adverse effects on human cardiovascular health. Nevertheless, there remains a lack of comprehensive understanding regarding the relationships between O3 exposure and the risk of cardiovascular diseases (CVD), as well as the underlying biological mechanisms. To address this knowledge gap, this narrative review meticulously summarizes the existing epidemiological evidence, susceptibility, and potential underlying biological mechanisms linking O3 exposure with CVD. An increasing body of epidemiological studies has demonstrated that O3 exposure heightens the incidence and mortality of CVD, including specific subtypes such as ischemic heart disease, hypertension, and heart failure. Certain populations display heightened vulnerability to these effects, particularly children, the elderly, obese individuals, and those with pre-existing conditions. Proposed biological mechanisms suggest that O3 exposure engenders respiratory and systemic inflammation, oxidative stress, disruption of autonomic nervous and neuroendocrine systems, as well as impairment of coagulation function, glucose, and lipid metabolism. Ultimately, these processes contribute to vascular dysfunction and the development of CVD. However, some studies have reported the absence of associations between O3 and CVD, or even potentially protective effects of O3. Inconsistencies among the literature may be attributed to inaccurate assessment of personal O3 exposure levels in epidemiologic studies, as well as confounding effects stemming from co-pollutants and temperature. Consequently, our findings underscore the imperative for further research, including the development of reliable methodologies for assessing personal O3 exposure, exploration of O3 exposure's impact on cardiovascular health, and elucidation of its biological mechanisms. These endeavors will consolidate the causal relationship between O3 and cardiovascular diseases, subsequently aiding efforts to mitigate the risks associated with O3 exposure.

Exposure to ambient air pollution and chronic bronchitis: Findings from over 6.6 million adults in northwestern China

BACKGROUND

Ambient air pollution increases the risk of respiratory mortality and morbidity, but evidence concerning effects of air pollution on chronic bronchitis (CB) is scarce. This study aimed to evaluate the associations of a set of air pollutants with the burden of CB, and to explore potential modifiers on the associations.

METHODS

In 2020, a total of 6,556,440 adults living in the Northwestern region of China were recruited. The Space-Time Extra-Trees model was employed to assess the annual average concentrations of six air pollutants for the three years (2017-2019) before 2020 , and subsequently allocated to the participants based on the latitude and longitude of their home addresses. We investigated the associations between the levels of various air pollutants and the odds of CB using generalized linear mixed models, and conducted multiple sensitivity analyses and subgroup analyses.

RESULTS

The odds of CB displays an approximately linear association with particulate matter with aerodynamic diameter ≤2.5 μm (PM2.5), particulate matter with aerodynamic diameter ≤10 μm (PM10), while it shows a non-linear relationship with gaseous pollutants. In the adjusted model, the odds ratios and 95% confidence intervals for CB per 10 μg/m3 increase in PM2.5, PM10, and sulfur dioxide (SO2) were 1.297 (1.262-1.332), 1.072 (1.064-1.080), and 2.587 (2.186-3.063), respectively. Furthermore, several additional sensitivity analyses demonstrated the stability of these associations. Subgroup analyses found that the aforementioned associations were greater among participants aged below 50 years old and those who smoked and had no leisure time exercise.

CONCLUSION

Long-term exposure to ambient air pollutants may increase the odds of CB, especially among younger people and those with unhealthy lifestyles.

Association of fine particulate matter and its constituents with hypertension: the modifying effect of dietary patterns

BACKGROUND

Studies have shown that nutritional supplements could reduce the adverse effects induced by air pollution. However, whether dietary patterns can modify the association of long-term exposure to fine particulate matter (PM2.5) and its constituents with hypertension defined by the 2017 ACC/AHA guideline has not been evaluated.

METHODS

We included 47,501 Chinese adults from a nationwide cross-sectional study. PM2.5 and five constituents were estimated by satellite-based random forest models. Dietary approaches to stop hypertension (DASH) and alternative Mediterranean diet (AMED) scores were calculated for each participant. Interactions between dietary patterns and air pollution were examined by adding a multiplicative interaction term to logistic models.

RESULTS

Long-term exposure to PM2.5 and its constituents was associated with an increased risk of hypertension and stage 1-2 hypertension. The DASH and AMED scores significantly modified these associations, as individuals with higher scores had a significantly lower risk of air pollution-related hypertension and stage 1-2 hypertension (P-interaction < 0.05), except for interaction between PM2.5, sulfate, nitrate, ammonium, and AMED score on stage 1 hypertension. For each IQR increase in PM2.5, participants with the lowest DASH and AMED quintiles had hypertension risk with ORs (95%CI) of 1.20 (1.10, 1.30) and 1.19 (1.09, 1.29), whereas those with the highest DASH and AMED quintiles had lower risks with 0.98 (0.91, 1.05) and 1.04 (0.97, 1.11). The stratified analysis found modification effect was more prominent in the < 65 years age group. Consuming more fresh vegetables, fruits, whole grains, and dairy would reduce the risk of hypertension caused by PM2.5 and its constituents.

CONCLUSIONS

Dietary patterns rich in antioxidants can reduce long-term exposure to PM2.5 and its constituents-induced hypertension defined by the 2017 ACC/AHA guideline, especially in young and middle-aged individuals. Compared to the Mediterranean diet, the DASH diet offers superior dietary guidance to prevent stage 1 hypertension caused by air pollution.

The Association between Air Pollutants Exposure with Pre- and Hypertension by Vitamin C Intakes in Korean Adults: A Cross-Sectional Study from the 2013-2016 Korea National Health and Nutrition Examination

OBJECTIVES

Oxidative stress and systemic inflammation are the main pathways by which air pollutants cause hypertension (HTN). Vitamin C intake may reduce the risk of HTN caused by air pollutants. This study aimed to investigate the association between air pollutants and pre-HTN and HTN in Korean adults and whether these associations were modified by vitamin C intake, using data from the 2013-2016 Korean National Health and Nutrition Examination Survey (KNHANES).

DESIGN

Cross-sectional study.

SETTING

This study used data from the KNHANES VI (2013-2015) and VII (2016) along with the data from the annual air pollution report of the Ministry of Environment.

PARTICIPANTS

We included 11,866 adults who had responded to a semi-food frequency questionnaire.

MEASUREMENTS

We used survey logistic regression models to evaluate the association of ambient PM10, SO2, NO2, CO, and O3 with pre-HTN and HTN according to vitamin C intake.

RESULTS

After adjusting for potential covariates, exposure to ambient PM10, SO2, NO2, and CO was significantly associated with a high prevalence of pre-HTN and HTN, whereas exposure to O3 was significantly associated with a low prevalence of pre-HTN and HTN. In particular, as the air pollutant scores increased (severe air pollution), the prevalence of pre-HTN and HTN increased in a dose-dependent manner (highest score vs. lowest score, OR=1.85, 95% CI=1.39-2.46, p for trend <.0001). However, these associations were found to be pronounced in adults with low vitamin C intake (highest score vs. lowest score, OR=2.30, 95% CI=1.50-3.54, p for trend <.0001), whereas the statistical significance disappeared for adults with high vitamin C intake (highest score vs. lowest score, OR=1.40, 95% CI=0.93-2.12, p for trend=0.007).

CONCLUSION

Exposure to air pollutants such as PM10, SO2, NO2, and CO may increase the prevalence of pre-HTN and HTN among Korean adults. In addition, a high intake of vitamin C may help prevent pre-HTN and HTN caused by air pollutants.

Associations of long-term ambient air pollution and traffic-related pollution with blood pressure and hypertension defined by the different guidelines worldwide: the CHCN-BTH study

The assessment of the generalization of the strict hypertension definition in the 2017 ACC/AHA Hypertension Guideline from environmental condition remains sparse. The aims of this study are to investigate and compare the associations of ambient air pollution and traffic-related pollution (TRP) with hypertension defined by the different criteria. A total of 32,135 participants were recruited from the baseline survey of the CHCN-BTH in 2017. We defined hypertension as SBP/DBP ≥ 140/90 mmHg according to the hypertension guidelines in China, Japan, Europe and ISH (traditional criteria) and defined as SBP/DBP ≥ 130/80 mmHg according to the 2017 ACC/AHA Hypertension Guideline (strict criteria). A two-level generalized linear mixed models were applied to investigate the associations of air pollutants (i.e. PM_2.5, SO₂, NO₂) and TRP with blood pressure (BP) measures and hypertension. Stratified analyses and two-pollutant models were also performed. The stronger associations of air pollutants were found in the hypertension defined by the strict criteria than that defined by the traditional criteria. The ORs per an IQR increase in PM_2.5 were 1.17 (95% CI: 1.09, 1.25) for the strict criteria and 1.14 (95% CI: 1.06, 1.23) for the traditional criteria. The similar conditions were also observed for TRP. The above results were robust in both stratified analyses and two-pollutant models. Our study assessed the significance of the hypertension defined by the strict criteria from environmental aspect and called attention to the more adverse effects of air pollution and TRP on the earlier stage of hypertension.

Abnormal fasting blood glucose enhances the risk of long-term exposure to air pollution on dyslipidemia: A cross-sectional study

Both long-term exposure to air pollution and abnormal fasting blood glucose (FBG) are linked to dyslipidemia prevalence. However, the joint role of air pollution and FBG on dyslipidemia remains unknown clearly. In this study, we aimed to test whether abnormal FBG could enhance the risks of long-term exposure to air pollutants on dyslipidemia in general Chinese adult population. The present study recruited 8917 participants from 4 cities in Hebei province, China. Participants' individual exposure to air pollutants was evaluated by the Empirical Bayesian Kriging statistical model in ArcGIS10.2 geographic information system. Dyslipidemia was defined according to Guidelines for the Prevention and Treatment of Dyslipidemia in Chinese Adults. Subjects were grouped into normal, prediabetes, diabetes according to FBG level. Generalized linear models were applied to analyze the interaction of air pollutants and FBG on dyslipidemia prevalence. The prevalence of dyslipidemia was 43.83% in our investigation. After adjusting all covariates, we found the risk of four air pollutants (PM_2.5, PM₁₀, NO₂, SO₂) on dyslipidemia prevalence was stronger as higher FBG level, and the adjusted odd ratio of interaction (OR_inter (95% CI)) between PM_2.5, PM₁₀, NO₂, SO₂ and FBG levels on dyslipidemia was 1.171 (1.162, 1.189), 1.119 (1.111, 1.127), 1.124 (1.115, 1.130), 1.107 (1.098, 1.115), respectively. Stratified analyses indicated the modifying effects of FBG on the association of air pollution with dyslipidemia were stronger among male, less than 65 years old, overweight/obesity (all P_inter<0.1). Our study concluded that high FBG levels strengthened the risk of long-term exposure to air pollution on dyslipidemia, especially more noticeable in male, less than 65 years old, overweight.

The association between anthropogenic heat and adult hypertension in Northeast China

OBJECTIVES

Although the potential serious threat of anthropogenic heat on human health was receiving considerable attention worldwide, its long-term health effect on blood pressure (BP) remained unknown. We aimed to evaluate the associations of long-term anthropogenic heat exposure with different components of BP and hypertension.

METHODS

In this cross-sectional study (Liaoning province, China) conducted in 2009, we included a total of 24,845 Chinese adults (18-74 years). We estimated the anthropogenic heat exposure in 2008 using multisource remote sensing images and ancillary data. We measured systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and pulse pressure (PP), and defined hypertension. We used generalized linear mixed model to examine the associations.

RESULTS

In the adjusted model, the estimates indicated that the difference in SBP, MAP and PP for those in highest quartiles of total anthropogenic heat exposure was greater compared with the lowest quartile (highest quartile: β = 1.11 [95% CI: 0.28-1.94], 0.60 [95% CI: 0.04-1.17], 0.76 [95% CI: 0.17-1.35]). Compared with the lowest quartile, the odds of hypertension were higher among those in higher quartiles (second quartile: OR = 1.17 [95% CI: 1.05-1.30]; third quartile:1.10 [95% CI: 1.1.01-1.21]; highest quartile: 1.17 [95% CI: 1.06-1.28]). These associations were stronger in female participants.

CONCLUSION

Our study showed that long-term exposure to anthropogenic heat was associated with elevated BP and higher odds of hypertension. These findings suggest that mitigation strategies to reduce anthropogenic heat should be considered.

Environmental pollution, a hidden culprit for health issues

The environmental and health impacts from the massive discharge of chemicals and subsequent pollution have been gaining increasing public concern. The unintended exposure to different pollutants, such as heavy metals, air pollutants and organic chemicals, may cause diverse deleterious effects on human bodies, resulting in the incidence and progression of different diseases. The article reviewed the outbreak of environmental pollution-related public health emergencies, the epidemiological evidence on certain pollution-correlated health effects, and the pathological studies on specific pollutant exposure. By recalling the notable historical life-threatening disasters incurred by local chemical pollution, the damning evidence was presented to criminate certain pollutants as the main culprit for the given health issues. The epidemiological data on the prevalence of some common diseases revealed a variety of environmental pollutants to blame, such as endocrine-disrupting chemicals (EDCs), fine particulate matters (PMs) and heavy metals. The retrospection of toxicological studies provided illustrative clues for evaluating ambient pollutant-induced health risks. Overall, environmental pollution, as the hidden culprit, should answer for the increasing public health burden, and more efforts are highly encouraged to strive to explore the cause-and-effect relationships through extensive epidemiological and pathological studies.

The influences of ambient fine particulate matter constituents on plasma hormones, circulating TMAO levels and blood pressure: A panel study in China

Considerable investigations have been carried out to address the relationship between ambient fine particulate matter (PM_2.5) and blood pressure (BP) in patients with hypertension. However, few studies have explored the influence of PM_2.5 and its constituents on Trimethylamine N-oxide (TMAO), an established risk factor for hypertension and cardiovascular disease (CVD), particularly in severely air-polluted areas. To explore the potential impact of PM_2.5 constituents on BP, plasma hormones, and TMAO, a panel study was conducted to investigate changes in BP, plasma hormones, and TMAO in response to ambient air pollution exposure in stage 1 hypertensive young adults. Linear mixed effect models were used to estimate the cumulative effects of fine particulate matters (PM_2.5) and its constituents on BP, plasma hormones and TMAO. We found that one interquartile range (IQR) (35 μg/m³) increase in 0-1 day moving-average PM_2.5 concentrations was statistically significantly associated with elevated systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) with estimated values of 0.13 (95% confidence interval (CI): 0.03 to 0.23) mmHg, 0.18 (95% CI: 0.08 to 0.28) mmHg, and 0.17 (95% CI: 0.09 to 0.26) mmHg, respectively. Hormone disturbance in the renin-angiotensin-aldosterone system was also associated with PM_2.5 exposure. Elevated TMAO levels with an IQR increase for 0-4, 0-5, 0-6 moving-average concentrations of PM_2.5 were found, and the increased values ranged from 26.28 (95% CI: 2.92 to 49.64) to 60.78 (31.95-89.61) ng/ml. More importantly, the PM_2.5-bound metal constituents, such as manganese (Mn), titanium (Ti), and selenium (Se) showed robust associations with elevated BP and plasma TMAO levels. This study demonstrates associations between PM_2.5 metal constituents and increased BP, changes in plasma hormones and TMAO, in stage 1 hypertensive young adults. Source control, aiming to reduce the emission of PM_2.5-bound metals should be implemented to reduce the risk of hypertension and CVD.

Street view greenness is associated with lower risk of obesity in adults: Findings from the 33 Chinese community health study

BACKGROUND

Urban greenness may protect against obesity, but very few studies have assessed 'street view' (SV) greenness metrics, which may better capture people's actual exposure to greenness compared to commonly-used satellite-derived metrics. We aimed to investigate these associations further in a Chinese adult study.

METHODS

Our analysis included 24,845 adults in the 33 Chinese Community Health Study in 2009. SV images from Tencent Map, segmented by machine learning algorithms, were used to determine the average proportion of green vegetation in SV images at community level in 800m road network buffer. Sensitivity analyses were performed with an alternative buffer size. Overall greenness was assessed as normalized difference vegetation index (NDVI) in 800 m buffer. We used predicted PM_2.5 and monitored NO₂ as proxies of air pollution. Body mass index (BMI), waist circumference (WC) and hip circumference (HC) were regressed on SV greenness by generalized linear mixed models, with adjustment for covariates. Mediation analyses were performed to assess the mediation effects of air pollution.

RESULTS

Each interquartile range (IQR = 3.6%) increase in street view greenness was associated with a 0.15 kg/m² (95% CI: -0.22, -0.09) decrease in BMI and 0.23 cm (95% CI: -0.35, -0.11) reduction in HC, and was associated with 7% lower odds of overweight (OR = 0.93, 95% CI:0.90, 0.96) and 18% lower odds of obesity (OR = 0.82, 95% CI:0.76, 0.89). Similar effect estimation was observed compared with commonly-used NDVI measures. PM_2.5 and NO₂ mediated 15.5% and 6.1% of the effects of SV greenness with BMI, respectively.

CONCLUSIONS

Our findings suggest beneficial associations between community-level SV greenness and lower body weight in Chinese adults. The effects were observed in women but not in men. Air pollution may partially mediate the association. These findings may have implications to support efforts to promote greening in urban areas.

Association of long-term exposure to ambient particulate pollution with stage 1 hypertension defined by the 2017 ACC/AHA Hypertension Guideline and cardiovascular disease: The CHCN-BTH cohort study

BACKGROUND

Evidence regarding the effects of ambient air pollution on new stage 1 hypertension defined by the 2017 ACC/AHA Hypertension Guideline remains sparse.

OBJECTIVES

To investigate the association of long-term exposure to ambient PM_2.5 with stage 1 hypertension and to explore the mediating and modifying effects of PM_2.5 on cardiovascular disease (CVD).

METHODS

A total of 32,135 participants aged 18-80 years were recruited in 2017. The three-year (2014-2016) average PM_2.5 concentrations were assessed by a spatial statistical model. Blood pressure (BP) was divided into four categories according to the 2017 ACC/AHA Hypertension Guideline: normal BP (SBP<120 mmHg and DBP<80 mmHg), elevated BP (SBP 120-129 mmHg and DBP<80 mmHg), stage 1 hypertension (SBP 130-139 mmHg or DBP 80-89 mmHg), and stage 2 hypertension (SBP≥140 mmHg or DBP≥90 mmHg or taking antihypertensive medications). The associations of PM_2.5 with BP categories were estimated by two-level generalized linear mixed models. Analyses stratified by age, mediation and interaction analyses of PM_2.5 and stage 1 hypertension with CVD were performed.

RESULTS

We detected a positive significant association between long-term exposure to PM_2.5 and stage 1 hypertension. Compared to normal BP, the OR was 1.05 (95% CI: 1.02, 1.08) per 10 μg/m³ increase in PM_2.5. The association was stronger than that of elevated BP but weaker than that of stage 2 hypertension. Stage 1 hypertension only partially mediated the association between PM_2.5 and CVD, and the mediation proportions ranged from 1.55% to 11.00%. However, it modified the association between PM_2.5 and CVD, which was greater in participants with stage 1 hypertension (OR: 1.66; 95% CI: 1.43, 1.93) than in participants with normal BP (OR: 1.32; 95% CI: 1.11, 1.57), with P_interaction<0.001. In the analysis stratified by age, the above associations were age-specific, and significant associations were only observed in the young and middle-aged (<60 years) groups.

CONCLUSIONS

Long-term exposure to ambient PM_2.5 was significantly associated with stage 1 hypertension. This earlier stage of hypertension may be a trigger BP range for adverse effects of air pollution in the development of hypertension and CVD, especially in young and middle-aged individuals.

Random forest model based fine scale spatiotemporal O3 trends in the Beijing-Tianjin-Hebei region in China, 2010 to 2017

Ambient ozone (O₃) concentrations have shown an upward trend in China and its health hazards have also been recognized in recent years. High-resolution exposure data based on statistical models are needed. Our study aimed to build high-performance random forest (RF) models based on training data from 2013 to 2017 in the Beijing-Tianjin-Hebei (BTH) region in China at a 0.01 ° × 0.01 ° resolution, and estimated daily maximum 8h average O₃ (O₃-8hmax) concentration, daily average O₃ (O₃-mean) concentration, and daily maximum 1h O₃ (O₃-1hmax) concentration from 2010 to 2017. Model features included meteorological variables, chemical transport model output variables, geographic variables, and population data. The test-R² of sample-based O₃-8hmax, O₃-mean and O₃-1hmax models were all greater than 0.80, while the R² of site-based and date-based model were 0.68-0.87. From 2010 to 2017, O₃-8hmax, O₃-mean, and O₃-1hmax concentrations in the BTH region increased by 4.18 μg/m³, 0.11 μg/m³, and 4.71 μg/m³, especially in more developed regions. Due to the influence of weather conditions, which showed high contribution to the model, the long-term spatial distribution of O₃ concentrations indicated a similar pattern as altitude, where high concentration levels were distributed in regions with higher altitude.

Long-Term Air Pollution and Blood Pressure in an African American Cohort: the Jackson Heart Study

INTRODUCTION

African Americans are disproportionately affected by high blood pressure, which may be associated with exposure to air pollutants, such as fine particulate matter and ozone.

METHODS

Among African American Jackson Heart Study participants, this study examined associations between 1-year and 3-year mean fine particulate matter and ozone concentrations with prevalent and incident hypertension at Visits 1 (2000-2004, n=5,191) and 2 (2005-2008, n=4,105) using log binomial regression. Investigators examined associations with systolic blood pressure, diastolic blood pressure, pulse pressure, and mean arterial pressure using linear regression and hierarchical linear models, adjusting for sociodemographic, behavioral, and clinical characteristics. Analyses were conducted in 2017-2019.

RESULTS

No associations were observed between fine particulate matter or ozone concentration and prevalent or incident hypertension. In linear models, an IQR increase in 1-year ozone concentration was associated with 0.67 mmHg higher systolic blood pressure (95% CI=0.27, 1.06), 0.42 mmHg higher diastolic blood pressure (95% CI=0.20, 0.63), and 0.50 mmHg higher mean arterial pressure (95% CI=0.26, 0.74). In hierarchical models, fine particulate matter was inversely associated with systolic blood pressure (-0.72, 95% CI= -1.31, -0.13), diastolic blood pressure (-0.69, 95% CI= -1.02, -0.36), and mean arterial pressure (-0.71, 95% CI= -1.08, -0.33). Attenuated associations were observed with 1-year concentrations and at Visit 1.

CONCLUSIONS

Positive associations were observed between ozone and systolic blood pressure, diastolic blood pressure, and mean arterial pressure, and inverse associations between fine particulate matter and systolic blood pressure, diastolic blood pressure, and mean arterial pressure in an African American population with high (56%) prevalence of hypertension. Effect sizes were small and may not be clinically relevant.

Associations of ambient particulate matter with homocysteine metabolism markers and effect modification by B vitamins and MTHFR C677T gene polymorphism

Evidence concerning effects of ambient air pollution on homocysteine (HCY) metabolism is scarce. We aimed to explore the associations between ambient particulate matter (PM) exposure and the HCY metabolism markers and to evaluate effect modifications by folate, vitamin B₁₂, and methylenetetrahyfrofolate reductase (MTHFR) C677T gene polymorphism. Between December 1, 2017 and January 5, 2018, we conducted a panel study in 88 young college students in Guangzhou, China, and received 5 rounds of health examinations. Real-time concentrations of PMs with aerodynamic diameter ≤2.5 (PM_2.5), ≤1.0 (PM_1.0), and ≤0.1 (PM_0.1) were monitored, and the serum HCY metabolism markers (i.e., HCY, S-Adenosylhomocysteine [SAH], and S-Adenosylmethionine [SAM]) were repeatedly measured. We applied linear mixed effect models combined with a distributed lag model to evaluate the associations of PMs with the HCY metabolism markers. We also explored effect modifications of folate, vitamin B₁₂, and the MTHFR C677T polymorphism on the associations. We observed that higher concentrations of PM_2.5 and PM_1.0 were associated with higher serum levels of HCY, SAH, SAM, and SAM/SAH ratio (e.g., a 10 μg/m³ increase in PM_2.5 during lag 0 day and lag 5 day was significantly associated with 1.3-19.4%, 1.3-28.2%, 6.2-64.4%, and 4.8-28.2% increase in HCY, SAH, SAM, and SAM/SAH ratio, respectively). In addition, we observed that the associations of PM_2.5 with the HCY metabolism markers were stronger in participants with lower B vitamins levels. This study demonstrated that short-term exposure to PM_2.5 and PM_1.0 was deleteriously associated with the HCY metabolism markers, especially in people with lower B vitamins levels.

Long-term effects of ambient PM2.5 on hypertension in multi-ethnic population from Sichuan province, China: a study based on 2013 and 2018 health service surveys

Hypertension, a major risk factor of many severe chronic diseases and leading cause of global disease burden, is reported to be associated with long-term exposure to PM_2.5. China's high PM_2.5 pollution level has become a major public health issue. However, existing studies from China have got inconsistent results with very limited investigation into the multi-ethnic peoples. This study adds multi-ethnic evidence from Sichuan Province, southwestern China, and assesses ethnic differences of PM_2.5 exposure effect on hypertension. We pooled large cross-sectional data from two surveys conducted in 2013 and 2018 to examine the association of long-term exposure to PM_2.5 on prevalence of hypertension in adults aged 30 years old and above. Community-specified annual PM_2.5 concentration was estimated using satellite data. Thirty-one thousand four hundred sixty-two participants with average exposure concentration of 32.8 μg/m³ were included. The proportions of the Han, the Tibetan, the Yi, and other ethnic people were 89.2%, 7.3%, 3.2%, and 0.3%, respectively. The adjusted odds ratio (OR) was 1.08 (95% CI, 1.04-1.12) for a 10 μg/m³ PM_2.5 concentration increment. The adjusted ORs for the Han, the Tibetan, and the Yi were 1.08 (95% CI, 1.04-1.12), 0.03 (95% CI, 0.00-0.27), and 1.75 (95% CI, 1.28-2.38) for a 10 μg/m³ PM_2.5 concentration increment, respectively. Stratification analysis found stronger associations in participants with chronic diseases and Yi minority population. The results showed that long-term exposure to PM_2.5 may increase the risk of hypertension prevalence in Chinese multi-ethnic adults. The associations were different among ethnicities.

Dynamic linkages among economic development, environmental pollution and human health in Chinese

Background

Research on the relationships between economic development, energy consumption, environmental pollution, and human health has tended to focus on the relationships between economic growth and air pollution, energy and air pollution, or the impact of air pollution on human health. However, there has been little past research focused on all the above associations.

Methods

The few studies that have examined the interconnections between the economy, energy consumption, environmental pollution and health have tended to employ regression analyses, DEA (Data Envelopment Analysis), or DEA efficiency analyses; however, as these are static analysis tools, the analyses did not fully reveal the sustainable economic, energy, environmental or health developments over time, did not consider the regional differences, and most often ignored community health factors. To go some way to filling this gap, this paper developed a modified two stage Undesirable Meta Dynamic Network model to jointly analyze energy consumption, economic growth, air pollution and health treatment data in 31 Chinese high-income and upper-middle income cities from 2013-2016, for which the overall efficiency, production efficiency, healthcare resource utilization efficiency and technology gap ratio (TGR) for all input and output variables were calculated.

Results

It was found that: (1) the annual average overall efficiency in China's eastern region was the highest; (2) the production stage efficiencies were higher than the healthcare resource utilization stage efficiencies in most cities; (3) the high-income cities had lower TGRs than the upper-middle income cities; (4) the high-income cities had higher average energy consumption efficiencies than the upper-middle income cities; (5) the health expenditure efficiencies were the lowest of all inputs; (6) the high-income cities' respiratory disease and mortality rate efficiencies were higher than in the upper-middle income cities, which had improving mortality rate efficiencies; and (7) there were significant regional differences in the annual average input and output indicator efficiencies.

Conclusions

First, the high-income cities had higher average efficiencies than the upper-middle income cities. Of the ten eastern region high-income cities, Guangzhou and Shanghai had average efficiencies of 1, with the least efficient being Shijiazhuang. In the other regions, the upper-middle income cities required greater technology and health treatment investments. Second, Guangzhou, Lhasa, Nanning, and Shanghai had production efficiencies of 1, and Guangzhou, Lhasa, Nanning, Shanghai and Fuzhou had healthcare resource utilization efficiencies of 1. As the average production stage efficiencies in most cities were higher than the healthcare resource utilization stage efficiencies, greater efforts are needed to improve the healthcare resource utilization. Third, the technology gap ratios (TGRs) in the high-income cities were slightly higher than in the upper-middle income cities. Therefore, the upper-middle income cities need to learn from the high-income cities to improve their general health treatment TGRs. Fourth, while the high-income cities had higher energy consumption efficiencies than the upper-middle income cities, these were decreasing in most cities. There were few respiratory disease efficiency differences between the high-income and upper-middle income cities, the high-income cities had falling mortality rate efficiencies, and the upper-middle income cities had increasing mortality rate efficiencies. Overall, therefore, most cities needed to strengthen their health governance to balance economic growth and urban expansion. Fifth, the average AQI efficiencies in both the high-income and upper-middle income cities were higher than the average CO₂ efficiencies. However, the high-income cities had lower average CO₂ emissions and AQI efficiencies than the upper-middle income cities, with the AQI efficiency differences between the two city groups expanding. As most cities were focusing more on air pollution controls than carbon dioxide emissions, greater efforts were needed in coordinating the air pollution and carbon dioxide emissions treatments. Therefore, the following suggestions are given. (1) The government should reform the hospital and medical systems. (2) Local governments need to strengthen their air pollution and disease education. (3) High-income cities need to improve their healthcare governance to reduce the incidence of respiratory diseases and the associated mortality. (4) Healthcare governance efficiency needs to be prioritized in 17 upper-middle income cities, such as Hangzhou, Changchun, Harbin, Chengdu, Guiyang, Kunming and Xi'an, by establishing sound medical management systems and emergency environmental pollution treatments, and by increasing capital asset medical investments. (5) Upper-middle income cities need to adapt their treatment controls to local conditions and design medium to long-term development strategies. (6) Upper-middle income cities need to actively learn from the technological and governance experiences in the more efficient higher-income cities.

Energy Efficiency and Health Efficiency of Old and New EU Member States

Environmental protection and health issues have always been of great concern. This study employed modified Meta-Frontier Dynamic Network Data Envelopment Analysis to explore the environmental pollution effects from energy consumption on the mortality of children and adults, tuberculosis rate, survival rate, and health expenditure efficiencies in 15 old EU states and 13 new EU states from 2010 to 2014. We calculated the overall efficiency scores and technology gap ratios for each old EU and new EU states as well as the efficiencies of non-renewable energy, renewable energy, PM2.5, CO₂, labor, GDP, tuberculosis, child mortality, adult mortality, health expenditure efficiency, and survival efficiency at the health stage. The average annual overall efficiencies of the old EU states are higher than that of the new EU states. Whether in terms of energy efficiencies or health efficiencies, the inputs and outputs of the old EU states are always higher than that of the new EU states. Overall, developing countries in Eastern Europe are lagging behind in terms of energy and health efficiencies. At the same time, the efficiency of child mortality is lower than that of adult mortality, and the efficiency of PM2.5 is higher than that of CO₂ in both old and new EU states.

The Energy Efficiency and the Impact of Air Pollution on Health in China

The rapid growth of China's economy in recent years has greatly improved its citizens' living standards, but economic growth consumes many various energy sources as well as produces harmful air pollution. Nitrogen oxides, SO₂ (sulfur dioxide), and other polluting gases are damaging the environment and people's health, with a particular spike in incidences of many air pollution-related diseases in recent years. While there have been many documents discussing China's energy and environmental issues in the past, few of them analyze economic development, air pollution, and residents' health together. Therefore, this study uses the modified undesirable dynamic two-stage DEA (data envelopment analysis) model to explore the economic, environmental, and health efficiencies of 30 provinces in China. The empirical results show the following: (1) Most provinces have lower efficiency values in the health stage than in the production stage. (2) Among the provinces with annual efficiency values below 1, their energy consumption, CO₂ (carbon dioxide), and NOx (nitrogen oxide) efficiency values have mostly declined from 2013 to 2016, while their SO₂ efficiency values have increased (less SO₂ emissions). (3) The growth rate of SO₂ efficiency in 2016 for 10 provinces is much higher than in previous years. (4) The health expenditure efficiencies of most provinces are at a lower level and show room for improvement. (5) In most provinces, the mortality rate is higher, but on a decreasing trend. (6) Finally, as representative for a typical respiratory infection, most provinces have a high level of tuberculosis efficiency, indicating that most areas of China are highly effective at respiratory disease governance.

Association between community greenness and obesity in urban-dwelling Chinese adults

Living in greener places may protect against obesity, but epidemiological evidence is inconsistent and mainly comes from developed nations. We aimed to investigate the association between greenness and obesity in Chinese adults and to assess air pollution and physical activity as mediators of the association. We recruited 24,845 adults from the 33 Communities Chinese Health Study in 2009. Central and peripheral obesity were defined by waist circumference (WC) and body mass index (BMI), respectively, based on international obesity standards. The Normalized Difference Vegetation Index (NDVI) was used to quantify community greenness. Two-level logistic and generalized linear mixed regression models were used to evaluate the association between NDVI and obesity, and a conditional mediation analysis was used also performed. In the adjusted models, an interquartile range increase in NDVI_500-m was significantly associated with lower odds of peripheral 0.80 (95% confidence interval [CI]: 0.74-0.87) and central obesity 0.88 (95% CI: 0.83-0.93). Higher NDVI values were also significantly associated with lower BMI. Age, gender, and household income significantly modified associations between greenness and obesity, with stronger associations among women, older participants, and participants with lower household incomes. Air pollution mediated 2.1-20.8% of the greenness-obesity associations, but no mediating effects were observed for physical activity. In summary, higher community greenness level was associated with lower odds of central and peripheral obesity, especially among women, older participants, and those with lower household incomes. These associations were partially mediated by air pollutants. Future well-designed longitudinal studies are needed to confirm our findings.

How Birth Season Affects Vulnerability to the Effect of Ambient Ozone Exposure on the Disease Burden of Hypertension in the Elderly Population in a Coastal City in South China

Birth season is an important factor that reflects prenatal nutritional conditions during early development, and which might have lifelong impacts on health. Moreover, ambient ozone pollution has been considered an important environmental risk factor for hypertension. However, whether birth season affects vulnerability to the effect of ambient ozone exposure on late-life hypertension is still unknown. A flexible case–crossover design was used to explore the effect of ambient ozone exposure on the disease burden of hypertension using years of life lost (YLL) in the elderly population in a coastal city in South China from 2013 to 2016. The influence of birth season was also explored. Ozone exposure was significantly associated with increased YLL from hypertension. The association was higher in the elderly individuals who were born in autumn than in those born in other seasons. Specifically, every 10 μg/m³ increase in ozone was associated with 0.68 (95% CI: 0.27, 1.10) YLL from hypertension in the elderly population born in autumn, while nonsignificant associations were found for those born in other seasons. The birth season, which affects the nutritional condition during early development, could affect vulnerability to the effect of ambient ozone exposure on the disease burden of hypertension in late life. The findings highlighted the importance of taking birth season into consideration when exploring the hypertensive effects of ozone exposure.

Statistical spatial-temporal modeling of ambient ozone exposure for environmental epidemiology studies: A review

BACKGROUND

Studies have discovered the adverse health impacts of ambient ozone. Most epidemiological studies explore the relationship between ambient ozone and health effects based on fixed site monitoring data. Fine modeling of ground-level ozone exposure conducted by statistical models has great advantages for improving exposure accuracy and reducing exposure bias. However, there is no review summarizing such studies.

OBJECTIVES

A review is presented to summarize the basic process of model development and to provide some suggestions for researchers.

METHODS

A search of PubMed, Web of Science and the Wanfang Database was performed for dates through July 1, 2019 to obtain relevant studies worldwide. We also examined the references of the articles of interest to ensure that as many articles as possible were included.

RESULTS

The land use regression model (LUR model), random forest model and artificial neural network model have been used in this field. We summarized these studies in terms of model selection, data preparation, simulation scale selection, and model establishment and validation. Multiparameters are a major feature of models. Parameters that influence the formation of ground-level ozone concentrations and parameters that have been extremely important in previous articles should be considered first. The process of model establishment and validation is essentially a process of continuously optimizing the model performance, but there are certain differences in the specific models.

CONCLUSION

This review summarized the basic process of the statistical model for ambient ozone exposure. We gave the applicable conditions and application scope of different models and summarized the advantages and disadvantages of various models in ozone modeling research. In the future, research is still needed to explore this area based on its own research purposes and capabilities.

Characteristics of Cerebral Stroke in the Tibet Autonomous Region of China

It is well known that cerebrovascular disease has become an important cause of adult death and disability. Strikingly, the Tibet Autonomous Region (TAR) ranks on the top in China for the incidence of stroke. To help explain this phenomenon, we have searched for and analyzed stroke-related literature for the TAR in the past 2 decades and have referenced reports from other regions at similar altitudes. This article focuses on epidemiology features, risk factors, and pathogenesis of stroke in the TAR in an effort to generate a better understanding of the characteristics of stroke in this region. The special plateau-related factors such as its high elevation, limited oxygen, the high incidence of hypertension, smoking, and the unique dietary habits of the region are correlated with the high incidence of stroke. In addition to these factors, the pathogenesis of stroke in this high-altitude area is also unique. However, there is no established explanation for the unique occurrence and high incidence of stroke in the TAR. Our study provides an important rationale not only for the clinic to prevent and treat this disease, but also for the government to develop appropriate health policies for the prevention of stroke in the TAR.

Dynamic Linkages among Economic Development, Energy Consumption, Environment and Health Sustainable in EU and Non-EU Countries

There is a close and important relationship between environmental pollution and public health, and environmental pollution has an important impact on the public health. This study employed the two-stage meta-frontier dynamic network data envelopment analysis (TMDN-DEA) model to explore the environment pollution effects from energy consumption on the mortality of children and adult, tuberculosis rate, survival rate and health expenditure efficiencies in 28 EU countries and 53 non-EU countries from 2010 to 2014. We calculated the overall efficiency scores and the technology gap ratios of each EU and non-EU countries and the efficiencies of input and output variables in the production and health stage. The average overall efficiencies each year in EU countries are higher than in the non-EU countries. But EU countries have higher energy efficiency than non-EU countries, and non-EU countries have higher health efficiency than EU countries. The health expenditure efficiencies in the EU countries are obviously lower than those in non-EU countries. The renewable energy efficiencies are obviously higher than the non-renewable energy efficiencies; PM2.5 efficiencies are obviously higher than the CO₂ efficiencies and the children’s mortality rate efficiencies are higher than the adult’s mortality rate efficiencies for EU countries and non-EU countries. The government management in the EU and non-EU countries should be strengthened to reduce the air pollutant and carbon dioxide emissions and raise energy transformation to the clean energy in renewable energy and improve health efficiencies in medical and health care field.

Energy and Health Efficiencies in China with the Inclusion of Technological Innovation

The price people pay for low energy efficiency includes not only high manufacturing costs, but also public health. With technological innovation as the driving factor for improving energy efficiency, this study uses two-stage dynamic undesirable data envelopment analysis (TDU-DEA) under variable return to scale to evaluate energy and health efficiencies with inclusion of technological innovation in 30 provinces of China over the period 2013–2016. The results show that the mean overall efficiencies and ranks in the eastern region are significantly higher than those in the non-eastern region, with or without the inclusion of technological innovations, and that energy efficiency in most provinces is higher than health efficiency. The average technological innovation efficiencies for energy conservation are higher than those for respiratory medical treatment. The former gap between the eastern region and non-east region is also smaller than the latter. Lastly, regions with the best technological innovation efficiencies are Beijing, Shanghai, Guangdong, Fujian, Hainan, Hebei, Inner Mongolia, Ningxia, Qinghai, Shandong, Shanxi, Tianjin, Xinjiang, and Yunnan.

Exposure to fine particles increases blood pressure of hypertensive outdoor workers: A panel study

BACKGROUND

Hypertension and air pollution are two important risk factors for cardiovascular morbidity and mortality. Although several studies suggest that air pollution has a significant impact on blood pressure, studies on long-term effects are sparse and still controversial.

OBJECTIVE

To evaluate the effects of exposure of outdoor workers to different levels of traffic-generated PM_2.5 on blood pressure.

DESIGN

This is an observational panel study.

PARTICIPANTS

88 non-smoking workers exposed to different concentrations of air pollution were evaluated weekly along four successive weeks.

MEASUREMENTS

In each week, personal monitoring of 24-h PM_2.5 concentration and 24-h ambulatory blood pressure were measured. The association between blood pressure variables and PM_2.5, adjusted for age, body mass index, time in job, daily work hours, diabetes, hypertension and cholesterol was assessed by means of multiple linear regression models fitted by least squares.

RESULTS

Exposure to PM_2.5 (ranging from 8.5 to 89.7 μg/m³) is significantly and consistently associated with an increase in average blood pressure. An elevation of 10 μg/m³ in the concentration of PM_2.5 is associated with increments of 3.9 mm Hg (CI 95% = [1.5; 6.3]) in average systolic 24-h blood pressure for hypertensive and/or diabetic workers.

CONCLUSION

Exposure to fine particles, predominantly from vehicular traffic, is associated with elevated blood pressure in hypertensive and/or diabetic workers.

Community greenness, blood pressure, and hypertension in urban dwellers: The 33 Communities Chinese Health Study

BACKGROUND

Living in greener areas has many health benefits, but evidence concerning the effects on blood pressure remains mixed. We sought to assess associations between community greenness and both blood pressure and hypertension in Chinese urban dwellers, and whether the associations were mediated by air pollution, body mass index, and physical activity.

METHODS

We analyzed data from 24,845 adults participating in the 33 Communities Chinese Health Study, which was conducted in Northeastern China during 2009. We measured each participant's blood pressure according to a standardized protocol. We assessed community greenness using two satellite-derived vegetation indexes - the Normalized Difference Vegetation Index (NDVI) and the Soil Adjusted Vegetation Index (SAVI). Particulate matter ≤2.5 μm and nitrogen dioxide were used as proxies of ambient air pollution. We applied generalized linear mixed models to investigate the association between greenness and blood pressure. We also performed mediation analyses.

RESULTS

Living in greener areas was associated with lower blood pressure and hypertension prevalence; an interquartile range increase in both NDVI_500-m and SAVI_500-m were significantly associated with reductions in systolic blood pressure of 0.82 mm Hg (95% CI: -1.13, -0.51) and 0.89 mm Hg (95% CI: -1.21, -0.57), respectively. The same increases in greenness were also significantly associated with a 5% (95% CI: 1%, 8%) and 5% (95% CI: 1%, 9%) lower odds of having hypertension, respectively. These associations remained consistent in sensitivity analyses. The associations were stronger among women than men. Air pollutants and body mass index partly mediated the associations, but there was no evidence of mediation effects for physical activity.

CONCLUSIONS

Our findings indicate beneficial associations between community greenness and blood pressure in Chinese adults, especially for women. Air pollution and body mass index only partly mediated the associations.

Acute effect of ambient air pollution on hospitalization in patients with hypertension: A time-series study in Shijiazhuang, China

Although numerous studies have investigated the association between air pollution and hospitalization, few studies have focused on the health effect of air pollution on populations with hypertension. In this study, we conducted a time-series study to investigate the acute adverse effect of six criteria ambient air pollutants (fine particulate matter [PM_2.5], inhalable particulate matter [PM₁₀], nitrogen dioxide [NO₂], sulfur dioxide [SO₂], ozone [O₃], and carbon monoxide [CO]) on hospitalization of patients for hypertension in Shijiazhuang, China, from 2013 to 2016. An over-dispersed Poisson generalized addictive model adjusting for weather conditions, day of the week, and long-term and seasonal trends was used. In addition, we evaluated the effect of modification by season, sex, and age. A total of 650,550 hospitalization records were retrieved during the study period. A 10 μg/m³ increase of PM_2.5 (lag06), PM₁₀ (lag06), NO₂ (lag03), O₃ (lag6), and CO (lag04) corresponded to 0.56% (95% confidence interval [CI]: 0.28-0.83%), 0.31% (95% CI: 0.12-0.50%), 1.18% (95% CI: 0.49-1.87%), 0.40% (95% CI: 0.09-0.71%), and 0.03% (95% CI: 0.01-0.05%) increments in hospitalization of patients for hypertension, respectively. We observed statistically significant associations with PM_2.5, PM₁₀, NO₂, O₃, and CO, while positive but insignificant associations with SO₂. The effects of PM_2.5, PM₁₀, NO₂, O₃, and CO were robust when adjusted for co-pollutants. We found stronger associations in the cool season than in the warm season. Moreover, there were non-significant differences in the associations between air pollution and sex or age group. This study suggests that patients with hypertension had an increased risk of hospital admission when exposed to air pollution.

Ambient PM1 air pollution, blood pressure, and hypertension: Insights from the 33 Communities Chinese Health Study

No evidence exists concerning the association between blood pressure and ambient particles with aerodynamic diameter ≤ 1.0 µm (PM₁), a major component of PM_2.5 (≤ 2.5 µm) particles, and potentially causing more hazardous health effects than PM_2.5. We aimed to examine the associations of blood pressure in adults with both PM₁ and PM_2.5 in China. In 2009, we randomly selected 24,845 participants aged 18-74 years from 33 communities in China. Using a standardized mercuric-column sphygmomanometer, we measured blood pressure. Long-term exposure (2006-08) to PM₁ and PM_2.5 were estimated using a spatial statistical model. Generalized linear mixed models were used to evaluate the associations between air pollutants and blood pressure and hypertension prevalence, controlling for multiple covariates. A 10-μg/m³ increase in PM₁ was significantly associated with an increase of 0.57 (95% CI 0.31-0.83) mmHg in systolic blood pressure (SBP), 0.19 (95% CI 0.03-0.35) mmHg increase in diastolic blood pressure (DBP), and a 5% (OR=1.05; 95% CI 1.01-1.10) increase in odds for hypertension. Similar associations were detected for PM_2.5. Furthermore, PM_1-2.5 showed no association with blood pressure or hypertension. In summary, both PM₁ and PM_2.5 exposures were associated with elevated blood pressure levels and hypertension prevalence in Chinese adults. In addition, most of the pro-hypertensive effects of PM_2.5 may come from PM₁. Further longitudinal designed studies are warranted to validate our findings.

Ambient PM1 air pollution and cardiovascular disease prevalence: Insights from the 33 Communities Chinese Health Study

BACKGROUNDS

Evidence on the association between long-term exposure to particulate matter with aerodynamic diameter ≤2.5 μm (PM_2.5) and cardiovascular disease (CVD) is scarce in developing countries. Moreover, few studies assessed the role of the PM₁ (≤1.0 μm) size fraction and CVD. We investigated the associations between PM₁ and PM_2.5 and CVD prevalence in Chinese adults.

METHODS

In 2009, we randomly recruited 24,845 adults at the age of 18-74 years from 33 communities in Northeastern China. CVD status was determined by self-report of doctor-diagnosed CVD. Three-year (2006-08) average concentrations of PM₁ and PM_2.5 were assigned using a satellite-based exposure. We used spatial Generalized Linear Mixed Models to evaluate the associations between air pollutants and CVD prevalence, adjusting for multiple covariates. Stratified and interaction analyses and sensitivity analyses were also performed.

RESULTS

A 10 μg/m³ increase in long-term exposure to ambient PM₁ levels was associated a 12% higher odds for having CVD (OR = 1.12; 95% CI = 1.05-1.20). Compared to PM₁, association between PM_2.5 and CVD was lower (OR = 1.06; 95% CI = 1.01-1.11). No significant association was observed for PM_1-2.5 (1-2.5 μm) size fraction (OR = 0.98; 95% CI = 0.85-1.13). Stratified analyses showed greater effect estimates in men and the elder.

CONCLUSIONS

Long-term PM₁ exposure was positively related to CVD, especially in men and the elder. In addition, PM₁ may play a greater role than PM_2.5 in associations with CVD. Further longitudinal studies are warranted to confirm our findings.

Associations of greenness with diabetes mellitus and glucose-homeostasis markers: The 33 Communities Chinese Health Study

BACKGROUND

Residing in greener places may be protective against diabetes mellitus (DM) but evidence is scarce and comes mainly from developed countries.

OBJECTIVES

To investigate associations of residential greenness with DM prevalence and glucose-homeostasis markers in Chinese adults and whether these associations were mediated by air pollution, physical activity, and body mass index.

METHODS

In 2009, a total of 15,477 adults from the cross-sectional 33 Communities Chinese Health Study provided blood samples and completed a questionnaire. We considered fasting and 2-h glucose and insulin concentrations, as well as the homoeostasis model assessment of insulin resistance and β-cell function, as glucose-homeostasis markers. DM was defined according to the American Diabetes Association's recommendations. Residential greenness was estimated by two satellite-derived vegetation indexes - Normalized Difference Vegetation Index (NDVI) and Soil Adjusted Vegetation Index (SAVI). Nitrogen dioxide and particulate matter ≤2.5 μm were used as air pollution proxies. Associations were assessed by two-level adjusted logistic and linear regression models.

RESULTS

A 0.1-unit increase in NDVI_{500 m} and SAVI_{500 m} was significantly associated with lower odds of DM by factors of 0.88 (95% Confidence Interval 0.82-0.94) and 0.80 (0.72-0.90), respectively. Higher greenness was also significantly associated with lower fasting and 2-h glucose levels, 2-h insulin level, as well as lower insulin resistance and higher β-cell function. Air pollution and body mass index significantly mediated 6.9-51.1% and 8.6-78.7% these associations, respectively, while no mediation role was observed for physical activity.

CONCLUSIONS

Higher residential greenness appears to be associated with a lower prevalence of DM. This association might be due to glucose and insulin metabolism and pancreatic β-cell function. Lower levels of air pollution and body mass index can be pathways linking greenspace to diabetes.

Air pollution and kidney disease: review of current evidence

Along with amazing technological advances, the industrial revolution of the mid-19th century introduced new sources of pollution. By the mid-20th century, the effects of these changes were beginning to be felt around the world. Among these changes, health problems due to environmental air pollution are increasingly recognized. At the beginning, respiratory and cardiovascular diseases were emphasized. However, accumulated data indicate that every organ system in the body may be involved, and the kidney is no exception. Although research on air pollution and kidney damage is recent, there is now scientific evidence that air pollution harms the kidney. In this holistic review, we have summarized the epidemiology, disease states and mechanisms of air pollution and kidney damage.

Exposure to ambient air pollution and blood lipids in adults: The 33 Communities Chinese Health Study

BACKGROUND

Little information exists on the lipidemic effects of air pollution, particularly in developing countries. We aimed to investigate the associations of long-term exposure to ambient air pollutants with lipid levels and dyslipidemias in China.

METHODS

In 2009, a total of 15,477 participants aged 18-74 years were recruited from the 33 Communities Chinese Health Study conducted in three Northeastern China cities. Total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were measured in participants' blood specimens. Three year (2006-08) average air pollution concentrations were assessed using data from 33 communities (particles with diameters ≤1.0 μm (PM₁) and ≤2.5 μm (PM_2.5) were predicted using a spatial statistical model) or 11 air monitoring stations (particles with diameters ≤10 μm (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and ozone (O₃)). Associations were evaluated by two-level logistic and generalized linear regression models.

RESULTS

We detected many significant associations between exposure to air pollutants (especially for PM₁ and PM_2.5) and blood lipid levels. Most of the associations suggested deleterious effects on blood lipid markers (e.g., a 10 μg/m³ increase in PM₁ was associated with 1.6% (95% confidence interval (CI): 1.1, 2.0), 2.9% (95% CI: -3.3, 9.3), and 3.2% (95% CI: 2.6, 3.9) higher levels of TC, TG, and LDL-C, respectively, but 1.4% (95% CI: -1.8, -0.9) lower HDL-C levels), although beneficial associations were found for O₃. In analysis with dyslipidemias, all the observed associations suggested deleterious lipidemic effects of air pollutants, and no significant beneficial association was observed for O₃. Stratified analyses showed that the associations were stronger in overweight or obese participants; sex and age modified the associations, but the pattern of effects was mixed.

CONCLUSIONS

Long-term ambient air pollution was associated with both altered lipid profiles and dyslipidemias, especially among overweight or obese participants.

Traffic-Related Particulate Matter and Cardiometabolic Syndrome: A Review

Traffic-related particulate matter (PM) is a major source of outdoor air pollution worldwide. It has been recently hypothesized to cause cardiometabolic syndrome, including cardiovascular dysfunction, obesity, and diabetes. The environmental and toxicological factors involved in the processes, and the detailed mechanisms remain to be explored. The objective of this study is to assess the current scientific evidence of traffic-related PM-induced cardiometabolic syndrome. We conducted a literature review by searching the keywords of “traffic related air pollution”, “particulate matter”, “human health”, and “metabolic syndrome” from 1980 to 2018. This resulted in 25 independent research studies for the final review. Both epidemiological and toxicological findings reveal consistent correlations between traffic-related PM exposure and the measured cardiometabolic health endpoints. Smaller sizes of PM, particularly ultrafine particles, are shown to be more harmful due to their greater concentrations, reactive compositions, longer lung retention, and bioavailability. The active components in traffic-related PM could be attributed to metals, black carbon, elemental carbon, polyaromatic hydrocarbons, and diesel exhaust particles. Existing evidence points out that the development of cardiometabolic symptoms can occur through chronic systemic inflammation and increased oxidative stress. The elderly (especially for women), children, genetically susceptible individuals, and people with pre-existing conditions are identified as vulnerable groups. To advance the characterization of the potential health risks of traffic-related PM, additional research is needed to investigate the detailed chemical compositions of PM constituents, atmospheric transformations, and the mode of action to induce adverse health effects. Furthermore, we recommend that future studies could explore the roles of genetic and epigenetic factors in influencing cardiometabolic health outcomes by integrating multi-omics approaches (e.g., genomics, epigenomics, and transcriptomics) to provide a comprehensive assessment of biological perturbations caused by traffic-related PM.

Pet exposure in utero and postnatal decreases the effects of air pollutants on hypertension in children: A large population based cohort study

The effect of ambient air pollution exposure on childhood hypertension has emerged as a concern in China, and previous studies suggested pet ownership is associated with lower blood pressure (BP). However, limited information exists on the interactive effects pet ownership and air pollution exposure has on hypertension. We investigated the interactions between exposure to pet ownership and air pollutants on hypertension in Chinese children. 9354 students in twenty-four elementary and middle schools (aged 5-17 years) in Northeastern China were evaluated during 2012-2013. Four-year average concentrations of particulate matter with aerodynamic diameter of ≤10 μm (PM10), SO2, NO2, and O3, were collected in the 24 districts from 2009 to 2012. Hypertension was defined as average diastolic or systolic BP (three time measurements) in the 95th percentile or higher based on height, age, and sex. To examine effects, two-level regression analysis was used, controlling covariates. Consistent interactions between exposure to pet and air pollutants were observed. Compared to children exposed to pet, those not exposed exhibited consistently stronger effects of air pollution. The highest odds ratios (ORs) per 30.6 μg/m3 increase in PM10 were 1.79 (95%confidence interval [95%CI]: 1.29-2.50) in children without current pet exposure compared to 1.24 (95%CI: 0.85-1.82) in children with current pet exposure. As for BP, only O3 had an interaction for all exposure to pet ownership types, and showed lower BP in children exposed to pet. The increases in mean diastolic BP per 46.3 μg/m3 increase in O3 were 0.60  mmHg (95%CI: 0.21, 0.48) in children without pet exposure in utero compared with 0.34  mmHg (95%CI: 0.21, 0.48) in their counterparts. When stratified by age, pet exposure was more protective among younger children. In conclusion, in this large population-based cohort, pet ownership is associated with smaller associations between air pollution and hypertension in children, suggesting pet ownership reduces susceptibility to the health effects of pollutants.

Long-term exposure to ambient air pollution (including PM1) and metabolic syndrome: The 33 Communities Chinese Health Study (33CCHS)

Little evidence exists about the effects of long-term exposure to ambient air pollution on metabolic syndrome (MetS). This study aimed to determine the association between long-term ambient air pollution and MetS in China. A total of 15,477 adults who participated in the 33 Communities Chinese Health Study (33CCHS) in 2009 were evaluated. MetS was defined based on the recommendation by the Joint Interim Societies. Exposure to air pollutants was assessed using data from monitoring stations and a spatial statistical model (including particles with diameters ≤ 1.0 µm (PM₁), ≤ 2.5 µm (PM_2.5), and ≤ 10 µm (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and ozone (O₃)). Two-level logistic regression analyses were utilized to assess the associations between air pollutants and MetS. The prevalence of MetS was 30.37%. The adjusted odds ratio of MetS per 10 µg/m³ increase in PM₁, PM_2.5, PM₁₀, SO₂, NO₂, and O₃ were 1.12 (95% CI = 1.00-1.24), 1.09 (95% CI = 1.00-1.18), 1.13 (95% CI = 1.08-1.19), 1.10 (95% CI = 1.02-1.18), 1.33 (95% CI = 1.12-1.57), and 1.10 (95% CI = 1.01-1.18), respectively. Stratified analyses indicated that the above associations were stronger in participants with the demographic variables of males, < 50 years of age, and higher income, as well as with the behavioral characteristics of smoking, drinking, and consuming sugar-sweetened soft drinks frequently. This study indicates that long-term exposure to ambient air pollutants may increase the risk of MetS, especially among males, the young to middle aged, those of low income, and those with unhealthy lifestyles.

Hypertension prevalence and living conditions related to air pollution: results of a national epidemiological study in Lebanon

Hypertension is a risk factor of several diseases, linked to high mortality and morbidity, particularly in developing countries. Some studies have linked indoor and outdoor pollution exposure items to hypertension, but results were inconsistent. Our objective was to assess the association of living conditions related to air pollution to hypertension in Lebanon, a Middle Eastern country. A national cross-sectional study was conducted all over Lebanon. Blood pressure and its related medications were assessed to be able to classify participants as hypertensive or not. Moreover, in addition to living conditions related to air pollution exposure, we assessed potential predictors of hypertension, including sociodemographic characteristics, self-reported health information and biological measurements. Furthermore, we assessed dose-effect relationship of air pollution items in relation with hypertension. Living conditions related to indoor and outdoor air pollution exposures were associated with hypertension, with or without taking biological values into account. Moreover, we found a dose-effect relationship of exposure with risk of disease (15% increase in risk of disease for every additional pollution exposure item), after adjustment for sociodemographics and biological characteristics (Ora = 1.15 [1.03-1.28]). Although additional studies would be necessary to confirm these findings, interventions should start to sensitize the population about the effect of air pollution on chronic diseases. The work on reducing pollution and improving air quality should be implemented to decrease the disease burden on the population and health system.