Association between short-term exposure to particulate matter air pollution and cause-specific mortality in Changzhou, China.

BACKGROUND: Extensive studies have linked ambient particulate matter (PM) to an increased mortality burden from a wide range of causes. However, the effects of PM on mortality rates from specific causes were unclear. This study aimed to estimate the detrimental effects of PM on cause specific deaths in Changzhou, China. METHOD: Data representing daily mortality rates, weather conditions and particulate air pollution levels were obtained from government-controlled agencies of Changzhou, from January 1, 2015 to December 31, 2016. An inverse distance weighting method was used to assess the population exposure to PM and a time-series was performed to detect the detrimental effects of PM. RESULTS: Positive associations were identified between PMs and daily mortality rates from non-accidental, circulatory, hypertensive, respiratory and chronic lower respiratory causes at a lag of 0-3 days. The effects of PMs were strongest on hypertensive mortality, with an increase of 5.27% (95% confidence interval (CI): 2.43-8.19%) and 3.52% (95% CI: 1.55-5.53%), per 10 µg/m3 increment in PM2.5 and PM10 respectively. The elderly exhibited a higher mortality risk with PMs exposure. Females were more vulnerable to circulatory, hypertensive and respiratory death while males were more sensitive to chronic lower respiratory and neurodegenerative mortality. The effects were stronger in warm seasons for circulatory mortality and stronger in cold seasons for respiratory mortality. CONCLUSION: These findings indicate that PM could exert adverse influences on the outcomes of several pathological processes, especially for women and the elderly with hypertension disease.

A population association study of PPAR δ gene rs2016520 and rs9794 polymorphisms and haplotypes with body mass index and waist circumference in a Chinese population.

BACKGROUND: Peroxisome proliferator-activated receptor (PPAR) gene plays an important role in obesity and PPAR δ protein is a potent inhibitor; however, few previous studies have focused on this gene. AIM: To investigate the association of haplotypes of PPAR δ gene rs2016520 and rs9794 with abnormal weight (BMI ≥ 24 kg/m(2)) and abdominal obesity (WC ≥ 90 cm for males and ≥ 80 cm for females) in a Chinese Han population. SUBJECTS AND METHODS: In total, 820 subjects (270 men, 550 women) were randomly selected from the PMMJS cohort population and no individuals were related. rs2016520 and rs9794 were detected by TaqMan fluorescence probe. Hardy-Weinberg equilibrium (HWE) was used to detect genotype typing errors by Fisher's exact test. Linkage disequilibrium (LD) between polymorphisms was estimated by using SHEsis. Two PPAR δ SNPs (rs2016520 and rs9794) were analysed by using the logistic regression model. RESULTS: After adjustment for covariates, the haplotype containing the rs1026520-C and rs9794-C alleles was associated with a statistically significant decreased risk of obesity (OR = 0.64; 95% CI = 0.48-0.84, p = 0.0015). Coincidentally, the haplotype containing the rs1026520-C and rs9794-C alleles was also associated with a statistically decreased risk of abdominal obesity after covariate adjustment (OR = 0.59, 95% CI = 0.45-0.77, p < 0.001). CONCLUSION: C-C haplotype, constructed from rs2016520 and rs9794 alleles, showed a significant protective effect for both abnormal weight and abdominal obesity.

Association of peroxisome proliferator-activated receptor α/δ/γ with obesity, and gene-gene interaction, in the Chinese Han population.

BACKGROUND: We investigated the association of 10 single-nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptors (PPARs) with obesity and the additional role of gene-gene interaction. METHODS: Participants were recruited within the framework of the Prevention of Multiple Metabolic Disorders and MS in Jiangsu Province cohort population survey of an urban community in China. In total, 820 subjects (513 nonobese adults, 307 obese adults) were randomly selected, and no individuals were consanguineous. Ten SNPs (rs135539, rs4253778, rs1800206, rs2016520, rs9794, rs10865710, rs1805192, rs709158, rs3856806, and rs4684847) were genotyped and analyzed. RESULTS: After covariate adjustment, minor alleles of rs2016520 in PPARδ and rs10865170 in PPARγ were associated with lower BMI (P < 0.01 for all). Generalized multifactor dimensionality reduction analysis showed significant gene-gene interaction among rs2016520, rs9794, and rs10865170 in 3-dimensional models (P = 0.0010); prediction accuracy was 0.6011 and cross-validation consistency was 9/10. It also showed significant gene-gene interaction between rs2016520 and rs10865170 in all 2-dimensional models (P = 0.0010); prediction accuracy was 0.6072 and cross-validation consistency was 9/10. CONCLUSIONS: rs2016520 and rs10865170 were associated with lower obesity risk. In addition, interaction was identified among rs2016520, rs9794, and rs10865170 in obesity.

Hypertriglyceridemic Waist Phenotype and Lipid Accumulation Product: Two Comprehensive Obese Indicators of Waist Circumference and Triglyceride to Predict Type 2 Diabetes Mellitus in Chinese Population.

PURPOSE: To determine whether hypertriglyceridemic waist (HTGW) and high lipid accumulation product (LAP) preceded the incidence of type 2 diabetes mellitus (T2DM), and to investigate the interactions of HTGW and LAP with other components of metabolic syndrome on the risk of T2DM. METHODS: A total of 15,717 eligible participants without baseline T2DM and aged 35 and over were included from a Chinese rural cohort. Cox proportional hazards regression models were used to estimate the association of HTGW and LAP with the incidence of T2DM, and the restricted cubic spline model was used to evaluate the dose-response association. RESULTS: Overall, 867 new T2DM cases were diagnosed after 7.77 years of follow-up. Participants with HTGW had a higher hazard ratio for T2DM (hazard ratio (HR): 6.249, 95% confidence interval (CI): 5.199-7.511) after adjustment for potential confounders. The risk of incident T2DM was increased with quartiles 3 and 4 versus quartile 1 of LAP, and the adjusted HRs (95% CIs) were 2.903 (2.226-3.784) and 6.298 (4.911-8.077), respectively. There were additive interactions of HTGW (synergy index (SI): 1.678, 95% CI: 1.358-2.072) and high LAP (SI: 1.701, 95% CI: 1.406-2.059) with increased fasting plasma glucose (FPG) on the risk of T2DM. Additionally, a nonlinear (P nonlinear < 0.001) dose-response association was found between LAP and T2DM. CONCLUSION: The subjects with HTGW and high LAP were at high risk of developing T2DM, and the association between LAP and the risk of T2DM may be nonlinear. Our study further demonstrates additive interactions of HTGW and high LAP with increased FPG on the risk of T2DM.

Short-term effects of ambient air pollutants and myocardial infarction in Changzhou, China.

Ambient air pollution had been shown strongly associated with cardiovascular diseases. However, the association between air pollution and myocardial infarction (MI) is inconsistent. In the present study, we conducted a time-series study to investigate the association between air pollution and MI. Daily air pollutants, weather data, and MI data were collected from January 2015 to December 2016 in Changzhou, China. Generalized linear model (GLM) was used to assess the immediate effects of air pollutants (PM2.5, PM10, NO2, SO2, and O3) on MI. We identified a total of 5545 cases for MI, and a 10-µg/m3 increment in concentrations of PM2.5 and PM10 was associated with respective increases of 1.636% (95% confidence interval [CI] 0.537-2.740%) and 0.805% (95% CI 0.037-1.574%) for daily MI with 2-day cumulative effects. The associations were more robust among males and in the warm season versus the cold one. No significant effect was found in SO2, NO2, or O3. This study suggested that short-term exposure to PM2.5 and PM10 was associated with the increased MI risks. Our results might be useful for the primary prevention of MI exacerbated by air pollutants.

Acute effects of air pollution on ischaemic stroke onset and deaths: a time-series study in Changzhou, China.

OBJECTIVE: To investigate the acute effect of air pollutants on ischaemic stroke (IS) and IS-related death. SETTING: Five urban districts in Changzhou, China, between 9 January 2015 and 31 December 2016. PARTICIPANTS: A total of 32 840 IS cases and 4028 IS deaths were enrolled. MAIN OUTCOME MEASURES: A time-series design, generalised additive model and multivariable regression model were used to examine the percentage change (95% CI) in daily IS counts and deaths with an IQR increase in air pollutant levels for different single or multiple lag days in single-pollutant and two-pollutant models. RESULTS: Daily IS counts increased 0.208% (95% CI 0.036% to 0.381%) with an IQR increment in the levels of nitrogen dioxide (NO2). The estimated risk of NO2 was more robust in males and in the cold season. For daily IS counts, the estimated effects of NO2 and sulfur dioxide (SO2) were more significant when adjusted for particulate matter with aerodynamic diameters <2.5 µm (PM2.5) and PM10. An IQR increment in the concentration of PM10, SO2 and NO2 significantly increased IS deaths with 6 days of cumulative effects (0.268%, 95% CI 0.007% to 1.528%; 0.34%, 0.088% to 0.592%; and 0.263%, 0.004% to 0.522%, respectively). Young individuals (<65 years old) had a higher IS mortality risk for PM2.5, PM10, NO2 and CO. For IS death, the effect estimates of SO2 in the elderly, females and the cold season were more pronounced; statistical significance was also identified for SO2 when adjusted for carbon monoxide (CO). CONCLUSIONS: This study suggested that short-term exposure to ambient NO2 was associated with increased IS risk. In addition, SO2 was associated with increased IS onset and death.

Protective Effects of Ambient Ozone on Incidence and Outcomes of Ischemic Stroke in Changzhou, China: A Time-Series Study.

The potential beneficial effect of ozone (O3) on stroke had been identified experimentally and clinically, but these effects remain controversial in population-based studies. This study aimed to explore the epidemiological association between O3 and risk of ischemic stroke. Ischemic stroke related health data and air pollution data were obtained from the Center for Disease Control and Prevention and Environmental Monitoring Center in Changzhou between 2015 and 2016, respectively. The associations between the short-term exposure to O3 and daily ischemic stroke onsets and deaths were examined based on time-series generalized additive Poisson model. During the study period, daily ischemic stroke onsets and deaths decreased 0.340% (95% confidence interval (CI) -0.559% to -0.120%) and 0.697% (95% CI -1.103% to -0.290%) with an interquartile range (IQR) (41.1 µg/m³) increase in levels of ambient O3, respectively. The protective effects of O3 were more significant in men and elders and in the cool season than those in women and young people and in the warm season, respectively. The negative association was independent of PM2.5, PM10, SO2, NO2 or CO exposure. Acute O3 exposure was associated with decreased risk of ischemic stroke. These findings will help provide new insights into the relationship between ischemic stroke and ambient O3 concentrations.

Interaction of smoking and obesity on type 2 diabetes risk in a Chinese cohort.

The aim of this study was to examine the independent and combined effects of current smoking and obesity on risk of type 2 diabetes (T2DM) in a Chinese cohort. We analyzed the data from a population-based prospective cohort of 3598 participants aged 35-74 years from Jiangsu, China. A Cox proportional hazards regression model was used to calculate the hazard ratio (HR) of T2DM and corresponding 95% confidence interval (CI), and to examine the interaction between current smoking and obesity on risk of T2DM. Compared with non-smokers, the hazard ratio of T2DM for current smokers was 4.16 (2.77-6.24). There was a significant interaction between current smoking and abdominal obesity on T2DM. RERI=2.84 (0.02-5.67), suggesting that there would be 2.84 relative excess risk due to the additive interaction; AP=0.48 (0.20-0.76), indicating that 48% of T2DM exposed to both risk factors was attributable to the additive interaction; and SI was 2.36 (1.15-4.87), suggesting that the risk of T2DM in obese smokers was 2.36 times as high as the sum of risks in the participants exposed to a single risk factor alone. We did not find a significant interaction between smoking and overall obesity on T2DM, but the incidence of T2DM in overall obese smokers was also highest. Both current smoking and abdominal obesity are strong risk factors of T2DM in the Chinese population. This study further demonstrates an additive interaction of current smoking and abdominal obesity on T2DM risk.

Comparison of the Suitability of 2 Years Change in Waist Circumference and Body Mass Index in Predicting Hypertension Risk: A Prospective Study in Chinese-Han.

BACKGROUND: Currently, obesity has become a worldwide health problem and yet little is known about the impact of changes in obesity indicator on incident hypertension. The aim of this study was to compare the impact of changes in the WC and BMI on incident hypertension in a cohort population. METHODS: After a baseline investigation, we conducted the first and the second follow-up assessments for subjects after 2 and 5 years, respectively. The associations between the changes in the WC and BMI (measured as the D-value, i.e., the value at the first follow-up minus the value at baseline) and the hazard ratio (HR) of incident hypertension were analyzed with a multilevel Cox proportional hazards regression model. RESULTS: Among 2778 participants without hypertension, 660 developed hypertension between the first and the second follow-up assessments. When both the BMI and WC D-values were included in the regression model, the WC D-value was a predictor of hypertension incidence in both sexes (OR= 1.03 and P values < 0.05 for men and women), but the BMI D-value was no longer a predictor of hypertension incidence in either sex (OR=1.04 for men and 1.01 for women, both P values >0.05). In both sexes, hypertension risk was higher for subjects whose BMI was modified but WC was categorically increasing than for subjects whose WC and BMI were both modified. CONCLUSIONS: Both WC and BMI changes were associated with hypertension, but a change in the WC was a better predictor of the hypertension.

Index of central obesity as a parameter to replace waist circumference for the definition of metabolic syndrome in predicting cardiovascular disease.

OBJECTIVE: To compare the suitability of metabolic syndrome definitions in predicting cardiovascular disease (CVD) risk. METHODS: We analyzed data from a population-based prospective cohort of 3598 participants from Jiangsu, China. Waist circumference was replaced with central obesity [index of central obesity (ICO), a ratio of waist circumference and height] in Cholesterol Education Program Adult Treatment Panel III (ICO-replaced ATPIII) and International Diabetes Federation (ICO-replaced IDF), respectively. Cox proportional-hazards regression model and the receiver operating characteristic curve (ROC curve) was used to evaluate the suitability of ATPIII, IDF, ICO-replaced IDF and ICO-replaced ATPIII in predicting CVD risk. RESULTS: ICO was a better parameter in predicting CVD risk by ROC curve analysis. The ROC curve analysis also showed that although ICO-replaced IDF and IDF had the higher degree of specificity, lower sensitivity, longer ROC curve distance, less area under the curve to identify CVD than ATPIII and ICO-replaced ATPIII, therefore ICO-replaced IDF and IDF seemed to be undesirable. However, there was no significant difference in area under the curve between ATPIII and ICO-replaced ATPIII in predicting CVD risk. But it seems that odds ratios for abnormal triglyceride and high-density lipoprotein levels increase slightly when using ICO, but decrease for hyperglycemia and hypertension when using ICO. CONCLUSION: ICO was a better predictor of abnormal triglyceride and high-density lipoprotein levels than waist circumference, but waist circumference was a better predictor of hyperglycemia and hypertension than ICO. However, we failed to support ICO as a better parameter for metabolic syndrome definition in predicting CVD risk compared with waist circumference.

Interaction of current alcohol consumption and abdominal obesity on hypertension risk.

The high prevalence of alcohol consumption and abdominal obesity and increased incidence of essential hypertension (EH) in China indicates that there may be an interaction between alcohol consumption and abdominal obesity on EH risk. Therefore, we aimed to examine the independent and combined effects of alcohol consumption and abdominal obesity on risk of EH in a Chinese cohort. We analyzed data from a population-based prospective cohort of 2778 participants aged 35-74 years from Jiangsu China who were free of hypertension, diabetes and CVD at enrollment and were followed for hypertension events. Cox proportional hazards regression model was used to calculate the hazard ratio (HR) of hypertension and corresponding 95% confidence interval (CI). Logistic regression model was used to examine the interaction between alcohol consumption and abdominal obesity on risk of hypertension. After adjusting for age, sex, smoking status, family history of hypertension, current alcohol consumption significantly increased EH risk. Compared with those without alcohol consumption, the hazard ratio of EH for participants with alcohol consumption was 1.65 (95% confidence interval 1.29-2.12). There was a statistically significant additive interaction between current alcohol consumption and abdominal obesity on EH risk. The risk of EH for current alcohol consumers with abdominal obesity was 4.49 times as high as the sum of risks in participants with a single condition alone. Both alcohol consumption and abdominal obesity are strong risk factors of EH in the Chinese population. Moreover, this study further demonstrates an additive interaction of alcohol consumption and abdominal obesity on EH risk.