Marriage contributes to higher obesity risk in China: findings from the China Health and Nutrition Survey.

BACKGROUND: To investigate the association between marriage and the prevalence of overweight and obesity in China. METHODS: We conducted cross-sectional and retrospective cohort analyses using a nationwide sample of 36,310 individuals from the China Health and Nutrition Survey [2004-2015]. RESULTS: The prevalence of overweight and obesity increased from 28.7% to 36.7% and from 8.0% to 14.5% between 2004 and 2015, respectively. The cross-sectional analysis showed that married individuals were at a higher risk of being overweight (OR =2.18; 95% CI, 1.90-2.51) or obese (OR =1.95; 1.57-2.43) than never-married individuals. Divorced/widowed individuals were also at a greater risk of being overweight (OR =1.80; 1.51-2.13) or obese (OR =1.67; 1.28-2.17) than never-married individuals. Retrospective cohort analysis showed that individuals who married during the study were 1.55 (1.13-2.11) times more likely to be overweight than those who remained never-married. Compared to those who remained never-married, individuals who remained married were 1.71 (1.42-2.07) and 1.45 (1.11-1.89) times more likely to be overweight and obese. Individuals who became divorced or widowed were more likely to be overweight (RR =1.59; 1.18-2.15) or obese (RR =1.63; 1.08-2.46) than those who remained never-married. However, the risk of being overweight or obese among those who became divorced or widowed did not differ significantly from the risk among those who remained married. CONCLUSIONS: Marriage contributes to an increased risk of overweight and obesity in China; however, this risk is not significantly reduced by exiting a marriage.

Air Pollution Status in 10 Mega-Cities in China during the Initial Phase of the COVID-19 Outbreak.

Over the past decades, urbanization and industrialization have led to a change in air quality, bringing researchers to a full realization of the damaging effects of human activities on the environment. This study focused on describing air quality during the initial phase of the Novel Coronavirus disease (COVID-19) pandemic (since there were fewer anthropogenic activities) in 10 Chinese mega-cities. Using the independent t-test, the means of air quality index (AQI) scores and individual air pollutants concentration during the outbreak were compared with the means before the outbreak. Cohen's d was estimated to quantify how much difference was observed. Based on the AQI score, the air quality in these 10 cities ranged from excellent (Shenzhen) to light pollution (Xi'an) with 44.8 µg m-3 and 119.7 µg m-3, respectively. In comparison to the 2019 air quality, Guangzhou and Wuhan noted major differences in air quality during the outbreak. Indicators of traffic pollution, particularly NO2, were significantly lower during the outbreak in all cities. Particulate matter pollution varied, with some cities observing lower concentrations and other higher concentrations during the outbreak. There was a significant decrease in air pollution levels during the outbreak. More researchers should observe changes in air quality during peculiar or major events. Implementation of stringent regulation on vehicle use should be considered in mega-cities. Relevant findings should be employed in emphasizing the detrimental effects of anthropogenic activities and support the need for stringent emission control regulations.

Interaction Effects of Air Pollution and Climatic Factors on Circulatory and Respiratory Mortality in Xi'an, China between 2014 and 2016.

Several studies have reported that air pollution and climatic factors are major contributors to human morbidity and mortality globally. However, the combined interactive effects of air pollution and climatic factors on human health remain largely unexplored. This study aims to investigate the interactive effects of air pollution and climatic factors on circulatory and respiratory mortality in Xi'an, China. Time-series analysis and the distributed lag non-linear model (DLNM) were employed as the study design and core statistical method. The interaction relative risk (IRR) and relative excess risk due to interaction (RERI) for temperature and Air Quality Index (AQI) interaction on circulatory mortality were 0.973(0.969, 0.977) and -0.055(-0.059, -0.048), respectively; while for relative humidity and AQI interaction, 1.098(1.011, 1.072) and 0.088(0.081, 0.107) respectively, were estimated. Additionally, the IRR and RERI for temperature and AQI interaction on respiratory mortality were 0.805(0.722, 0.896) and -0.235(-0.269, -0.163) respectively, while 1.008(0.965, 1.051) and -0.031(-0.088, 0.025) respectively were estimated for relative humidity and AQI interaction. The interaction effects of climatic factors and AQI were synergistic and antagonistic in relation to circulatory and respiratory mortality, respectively. Interaction between climatic factors and air pollution contributes significantly to circulatory and respiratory mortality.

Association between PM2.5 and mortality of stomach and colorectal cancer in Xi'an: a time-series study.

Globally, fine particulate matter has been associated with several health problems including cancer. However, most studies focused mainly on lung cancer. Stomach and colorectal cancers play significant roles in increasing public health's cancer globally. This study focused on investigating a possible significant association between exposure to fine particulate matter (PM2.5) and mortality due to stomach and colorectal cancer in Xi'an from 2014 to 2016. Using time-series analysis, the study applied both single and multi-pollutant(s) approaches for investigations; PM2.5 was the pollutant of interest. Generalized additive model (GAM) was the core statistical method used with the addition of distributed lag model (DLM) to observe delayed effects. As a single pollutant, PM2.5 was significantly associated with stomach cancer mortality only RR (95%CI): 1.0003 (1.0001, 1.002). For the multi-pollutant analysis, PM2.5 combinations with NO2 were significantly associated with both stomach and colorectal cancer mortality RR (95%CI): 1.0103 (1.009, 1.021) and 1.054 (1.0324, 1.0667), respectively. Also, PM2.5 combination with O3 was significantly associated with colorectal cancer mortality, RR (95%CI): 1.0151 (1.0091, 1.0172), but no association was noted for combination with SO2. Though this study has reported significant associations, it will be beneficial for the public's health if more studies further investigate the relationship between exposure to PM2.5 and other cancer mortality.

Ambient air pollution and respiratory mortality in Xi'an, China: a time-series analysis.

BACKGROUND: Although air pollution is a known fundamental problem in China, few studies have investigated the associations between ambient air pollution and respiratory mortality in non-metropolitan cities of China. The study aimed to investigate a potential relationship between short-term exposure to ambient air pollutants and respiratory mortality in Xi'an, China. METHODS: Daily averages of PM2.5, SO2, O3, temperature, relative humidity and daily counts of respiratory mortality were obtained (2014-2016). Using a single and multi-pollutant approach in time-series analysis, the generalized additive model with natural splines was used for analysis. Subgroup analysis stratified by gender and age group (≤ 64 years and ≥ 65 years) was conducted. RESULTS: Seven thousand nine hundred sixty-five cases of respiratory mortality were assessed, with 62.9, 28.5, and 8.6% of mortality attributed to chronic lower respiratory diseases, influenza and pneumonia, as well as other forms of respiratory diseases, respectively. Observed pollutants were significantly associated with respiratory mortality. In the single pollutant model, 10 µg/m3 increase in a two-day moving average of PM2.5, and SO2 concentrations were significantly associated with relative risk 1.313(1.032, 1.708) and 1.4020(0.827, 2.854) of respiratory mortality, respectively. The effects of both air pollutants remained statistically significant after adjusting for collinearity in the multi-pollutant model. Ozone was only statistically associated with respiratory mortality in females at lag 0 [RR: 0.964(0.938, 0.991)]. CONCLUSION: This study provided evidence that respiratory mortality in Xi'an was significantly associated with exposure to ambient air pollutants from 2014 to 2016.

The effect of ambient air pollution on circulatory mortality: a short-term exposure assessment in Xi'an, China.

Various studies have illustrated that exposure to ambient air pollution has negative impacts on health. However, little evidence exists on the effects of ambient air pollution on circulatory mortality in Xi'an, China. This study aims to investigate and ascertain the association between short-term exposure to ambient air pollutants and circulatory mortality in Xi'an, China. Daily average concentrations of PM2.5, SO2, and O3, meteorological data (temperature and relative humidity) and daily counts of circulatory mortality were obtained between January 2014 and June 2016. Mortality was stratified by gender and age group (≤ 64 years and ≥ 65 years). A generalized additive model (GAM) with natural splines (NS) was constructed to analyze the relationship between ambient air pollutants and daily circulatory mortality. There were 57,570 cases of circulatory mortality, with cerebrovascular and ischemic heart diseases accounting for 48.5% and 43.5%, respectively. All ambient air pollutants displayed different seasonal patterns. In the single pollutant model, 10 µg/m3 increase in 2-day moving average concentrations of PM2.5, SO2, and O3 was associated with relative risk of 1.288(1.198, 1.388), 1.360(0.877, 2.331), and 1.324(1.059, 1.705) in circulatory mortality, respectively. After adjusting for collinearity in the multi-pollutant model, the effects remained statistically significant. The ≥ 65 years and female sub-groups were associated with a higher risk of circulatory mortality. Short-term exposure to ambient air pollutants plays a pivotal role in the genesis of circulatory mortality in Xi'an. Responses to ambient air pollutants exposure in relation to circulatory mortality are different when analyzed by sub-groups.