The association between outdoor light at night exposure and adult obesity in Northeastern China.

Previous studies have linked exposure to light at night (LAN) with various health outcomes, but evidence is limited for the LAN-obesity association. Thestudy analysed data from 24,845 participants of the 33 Communities Chinese Health Study and obesity (BMI ≥28 kg/m2) was defined according to the Working Group on Obesity in China. The Global Radiance Calibrated Nighttime Lights data were used to estimate participants' LAN exposure. The mixed-effect regression models examined the LAN-BMI and LAN-obesity association. We found that higher LAN exposure was significantly associated with greater BMI and higher risk of obesity. Changes of BMI and the odds ratios (ORs) of obesity and 95% confidence intervals (CIs) for 2nd, 3rd, and 4th against the 1st quartile of LAN exposure were 0.363 (0.208, 0.519), 0.364 (0.211, 0.516) and 0.217 (0.051, 0.383); 1.228 (1.099, 1.371), 1.356 (1.196, 1.538) and 1.269 (1.124, 1.433), respectively. Age and regular exercise showed significant modification effects on the LAN-obesity association.

Is residential greenness associated with dyslipidemia and lipid levels in Chinese rural-dwelling adults? The Henan rural cohort study.

Scarce epidemiologic research examined the associations between residential greenness and dyslipidemia or lipid levels in low/middle-income countries. Baseline statistics (2015-2017) of 39,259 rural-dwelling adults were obtained from a Chinese longitudinal study. The blood lipid level was measured utilizing an enzymatic assay method. According to the 2016 Chinese guidelines on dyslipidemia (revision), patients with dyslipidemia were defined. Participants' exposure to residential greenness was characterized by the satellite-based normalized difference vegetation index (NDVI). Mixed effects logistic regression and mixed effects linear regression were performed to assess the associations of residential greenness with dyslipidemia and lipid levels. The median (interquartile range, IQR) of 3-year average NDVI1000-m was 0.521 (0.089) units. Each IQR increase in NDVI1000-m was significantly linked with increased odds of hyperbetalipoproteinemia (OR = 1.33, 95%CI 1.21-1.46). The same increment in NDVI1000-m was associated with lower total cholesterol (TC) levels and increased low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels. For instance, the %changes in HDL-C levels was 0.71% (95%CI 0.17%-1.26%). The above relationships were partially mediated by reducing air pollution and lowering body mass index (BMI). Interaction effect analysis observed the greenness-lipid association was stronger in males than females (i.e., NDVI1000-m-TC association). Long-term exposure to residential greenness was associated with odds of dyslipidemia and lipid levels in Chinese rural-dwelling adults, particularly among males. Considering the cross-sectional study design, more longitudinal studies are needed to identify the causal associations.

Outdoor light at night and autism spectrum disorder in Shanghai, China: A matched case-control study.

BACKGROUND: Several environmental factors have been identified to be associated with autism spectrum disorder (ASD) over the past decades. However, evidence is limited for the effect of exposure to outdoor light at night (LAN) on ASD in China and even elsewhere in the world. METHODS: Participants in this study were from a multi-stage sampling survey on ASD conducted between June 2014 and October 2014 among children aged 3-12 years in Shanghai, China. All participants underwent a two-stage screening of ASD via questionnaire, and then, suspected cases were finally diagnosed by clinical examination. For data analyses, each ASD case was randomly matched with 10 healthy controls by age and sex. The LAN data were extracted from the stable lights product of the US Defense Meteorological Satellite Program's Operational Linescan System (DMSP-OLS) according to geolocation information of residential addresses. Mean levels of exposure to LAN during the 3 years after birth and 1 year before birth were calculated. We used conditional logistic regression models to examine the association between LAN and ASD. RESULTS: We investigated 84,934 children from 96 kindergartens, 55 primary schools, and 28 special education schools, and 203 children were diagnosed as ASD cases. A total of 1727 children (157 ASD cases and 1570 healthy controls) were included in the final analyses. Brighter LAN exposures after and before birth were significantly associated with higher risk of ASD. After adjusting for potential covariates, adjusted odd ratios and 95% confidence intervals associated with per unit increase in LAN were 1.066 (1.027, 1.107) during the 3 years after birth and 1.046 (1.018, 1.075) during the 1 year before birth. CONCLUSIONS: Results of our study concluded brighter LAN exposure was significantly associated with higher risk of ASD among Chinese children, which suggested that outdoor LAN could be a potential risk factor of ASD.

Association of air pollution and greenness with carotid plaque: A prospective cohort study in China.

Previous studies indicated that exposure to air pollution was associated with the progress of atherosclerosis, but evidence is very limited in China and even in the world. This study aims to assess the associations of long-term exposures to air pollution and greenness with the occurrence of carotid plaque. Participants of this cohort study were urban residents and office workers who visited Hebei General Hospital for routine physical examination annually from September 2016 through to December 2018. Eligible participants were people diagnosed the absence of carotid plaque clinically at their first hospital visit and were followed up at their second or third hospital visit. Exposure to particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5), nitrogen dioxide (NO2) and ozone (O3) were estimated using an inverse distance weighted (IDW) method. The level of greenness was assessed using the Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). The associations were evaluated using Cox proportional hazards regression models. Among 4,137 participants, 575 showed the occurrence of carotid plaque during the follow-up period. After controlling for potential confounders, the hazard ratios (HRs) and 95% confidence intervals (95%CIs) of carotid plaque associated with per interquartile range (IQR) increase in PM2.5, NO2, and O3 were 1.78 (1.55, 2.03), 1.32 (1.14, 1.53) and 1.99 (1.71, 2.31), respectively. Increased EVI and NDVI were significantly associated with lower risk of carotid plaque [HR (and 95%CI): 0.84 (0.77, 0.93) and 0.87 (0.80, 0.94)]. PM2.5 significantly mediated 80.47% or 93.00% of the estimated association between EVI or NDVI and carotid plaque. In light of the significant associations between air pollution, greenness and carotid plaque in this study, continued efforts are needed to curb air pollution and plan more green space considering their effects on vascular disease.

The association between ambient air pollution and blood lipids: A longitudinal study in Shijiazhuang, China.

BACKGROUND: Few studies have explored the associations between ambient air pollution and blood lipid levels. This study aimed to fill this knowledge gap based on a routine health examination cohort in Shijiazhuang, China. METHODS: We included 7063 participants who took the routine health examination for 2-3 times at Hebei General Hospital from January 2016 to December 2018. Individual serum levels of cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured. Their three-month average exposure to air pollution prior to the routine health examinations was estimated using inverse distance weighted method. We used linear mixed-effects regression models to examine the associations between air pollution and levels of blood lipids while controlling for age, gender, body mass index (BMI), smoking, alcohol drinking, temperature, humidity, with a random effect for each individual. RESULTS: Particles with diameters ≤2.5 µm and ≤10 µm (PM2.5 and PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2) and ozone (O3) were all positively associated with TC, TG, and LDL-C and negatively associated with HDL-C, in single pollutant models. Each 10 µg/m3 increment of 3-month average PM2.5 was associated with 0.65% [95% confidence interval (CI): 0.03%-1.28%], 0.56% (95%CI: 0.33%-0.79%) and 0.63% (95%CI: 0.35%-0.91%) increment in TG, TC, and LDL-C, and 0.91% (95%CI: 0.68%-1.13%) decrease in HDL-C. In two-pollutant models, the effects of gaseous pollutants on blood lipids were weakened, while those of PMs were strengthened. Stronger associations were presented in the elderly (≥60 years) and overweight/obese (BMI ≥ 24) participants. CONCLUSIONS: Ambient air pollution had significantly adverse effects on blood lipid levels, especially in overweight/obese and elderly individuals. CAPSULE: Significant associations between increased air pollution and worse blood lipid levels were found, especially in overweight/obese and elderly individuals.

Association between residential greenness and sleep quality in Chinese rural population.

BACKGROUND: Epidemiological studies on the association of residential greenness with sleep quality are limited in China. OBJECTIVE: This study aims to investigate the association of long-term exposure to residential greenness with sleep quality in rural China. METHODS: In our study, 27,654 rural residents were selected from 4 counties of Henan Province by a multi-stage stratified cluster sampling method. Participants' sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). The Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI), two satellite-derived vegetation indexes, were used to assess the level of residential greenness. Long-term greenness exposure was defined as the averages of NDVI and EVI during the three years prior to the baseline survey. The relationship between sleep quality and greenness was assessed using the mixed-effect linear regression models. RESULTS: Among 27,654 rural residents, the mean age was 55.89 years (standard deviation, SD = 12.22) and 60.18% of them were female. In the crude model, the PSQI score decreased with per interquartile range (IQR) increase in EVI and NDVI [ΔPSQI score (95% confidence interval, 95%CI): -0.073 (-0.115, -0.030) and -0.047 (-0.089, -0.002)]. After controlling potential confounders, ΔPSQI scores and 95%CIs were -0.055 (-0.095, -0.012) and -0.090 (-0.151, -0.025) associated with per IQR increment in EVI and NDVI. The results of stratified analyses showed the effect of residential greenness on sleep was stronger among males and individuals with higher household income and educational attainment than females and those with lower household income and educational attainment. Moreover, the modification effect of air pollution was observed in the greenness-sleep association. CONCLUSIONS: Our study indicated that higher residential greenness was significantly associated with better sleep quality in Chinese rural population, which highlights the significant effect of green space on human health.

Associations of Residential Greenness with Depression and Anxiety in Rural Chinese Adults.

BACKGROUND: Depression and anxiety are top contributors to non-fatal health loss globally. Several studies have indicated the association between residential greenness and mental health. METHOD: The participants (n = 27,366) were recruited from four counties in Henan Province, China during 2015-2017. Symptoms of depression and anxiety were evaluated using the Patient Health Questionnaire-2 (PHQ-2) and the Generalized Anxiety Disorder-2 (GAD-2) in the baseline survey. The level of residential greenness during the 3-year period before the baseline survey was assessed using the Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). The mixed-effect linear regression model was applied to examine the associations of residential greenness with depression and anxiety. RESULTS: The results of adjusted models showed that the score of PHQ-2 (Δscore and 95% confidence interval [CI]) decreased by -0.024 (-0.041, -0.006) and -0.022 (-0.038, -0.004) with an interquartile range (IQR) increase in NDVI and EVI within a 1,000-m buffer radius, respectively. The score of GAD-2 (Δscore and 95% CI) decreased by -0.024 (-0.040, -0.006) and -0.028 (-0.044, -0.011), in relation to an IQR increase in NDVI and EVI within a 1,000-m buffer radius, respectively. CONCLUSIONS: A higher level of residential greenness was significantly associated with lower risk of depression and anxiety in rural areas of Henan Province. Improving residential greenness accessibility may help to promote the mental health of rural populations.