| Part Ⅰ Long-term Exposure to Fine Particulate Matter Worsen the Surrogate Indicators of Insulin ResistanceBackground and ObjectivesThough animal experimental evidences suggested adverse impact of fine particulate matter(PM2.5)on insulin resistance,whether PM2.5 exposure could worsen the insulin resistance level of human remains controversial.We aimed to examine the associations between long-term PM2.5 exposure and five surrogate indicators of insulin resistance including triglyceride-glucose(TyG)index,TyG with body mass index(TyG-BMI),TyG with waist circumference(TyG-WC),TyG with waist to height ratio(TyG-WHtR),and metabolic score for insulin resistance(METS-IR)in the project of Prediction for Atherosclerotic Cardiovascular Disease Risk in China(China-PAR).The modification effects of dietary intake and genetic susceptibility on the associations between PM2.5 and surrogate indocators of insulin resistance were further explored.MethodsIndividuals from three sub-cohorts of China-PAR Project who participated in the 2007-2008 or 2012-2015 survey were included in our analysis,with their information on unified questionnaire,physical examination,blood biochemical test and genotyping data.A satellite-based spatio-temporal model was used for estimating ambient PM2.5 exposure at 1×1 km spatial resolution.The genetic risk of insulin resistance was mediately assessed by the polygenic risk score(PRS)of body mass index(BMI),diabetes,total cholesterol(TC),triglyceride(TG),high-density lipoprotein cholesterol(HDL-C)and low-density lipoprotein.cholesterol(LDL-C).The generalized estimating equation(GEE)was used to evaluate the adverse impact of PM2.5 on the indicators with repeat measurement of incomplete duplication design.Stratified analyses were further conducted to explore whether the basic characteristics and dietary intake of participants could modify the association between PM2.5 and insulin resistance.The GEE model was also used to assess the association of PRS with each indicator.The interaction between PRS and PM2.5 was evaluated by stratified analyses of PRS,joint analyses of PRS and PM2.5,and multiplicative interaction test.ResultsA total of 99216 participants were included in our current study,162060 observations were finally included in our main analyses,and 64000 observations among which were included in the genetic susceptibility analyses.Each 10 μg/m3 increment of PM2.5 was associated with an increase of 0.019(95%confidence interval(CI):0.016,0.021),4.132(95%CI:3.974,4.291),10.779(95%CI:10.310,11.247),0.059(95%CI:0.056,0.062)and 0.694(95%CI:0.664,0.725)in TyG,TyG-BMI,TyG-WC,TyG-WHtR and METS-IR,respectively.Compared with the first quartile.of PM2.5 concentration,participants had the increased levels of five surrogate indicators,e.g.TyG increased by 0.110(95%CI:0.102,0.119),0.243(95%CI:0.233,0.253)and 0.013(95%CI:0.004,0.022)in the second to fourth quartile,respectively.The adverse impacts of PM2.5 on surrogate indicators in people with unhealthy diet were significantly stronger than those in people with healthy diet.Sufficient intake of fresh fruits and vegetables,fish and tea can effectively reduce the adverse effect of PM2.5 on insulin resistance.BMI and lipid-related PRS were significantly associated with all surrogate indicators of insulin resistance,while diabetes-related PRS was only significantly associated with TyG.After adjustment for multiple testing,there was no significant multiplicative interaction between BMI,diabetes and lipid-related PRS and long-term PM2.5 exposure on the five surrogate indicators of insulin resistance.ConclusionThis study provided evidence on the adverse effects of long-term PM2.5 exposure on five surrogate indicators of insulin resistance based on a large population,and found that healthy diet and dietary components could ameliorate the effect of PM2.5 on insulin resistance.This suggests that it is quite urgent to improve air quality and strengthen the healthy lifestyle interventions for the whole population.Part Ⅱ Effect of Air Pollution on Heart Failure:Systematic Review and Meta-AnalysisBackground and ObjectivesHeart failure(HF)poses a significant global disease burden.The current evidence on the impact of air pollution on HF remains inconsistent.We aimed to conduct a systematic review of the literature and meta-analysis to provide a more comprehensive and multi-perspective assessment of the associations between shortand long-term air pollution exposure and HF from epidemiological evidences in human.MethodsThree databases were searched up to August 31,2022 for studies investigating the association between air pollutants[PM2.5,particulate matter(PM10),nitrogen dioxide(NO2),sulphur dioxide(SO2),carbon monoxide(CO),ozone(O3)]and HF hospitalization,incidence or mortality.A random-effect model was used to derive the relative risks(RR)and their 95%confidence intervals(CIs)of the pooled estimations of HF risk.Subgroup analysis was conducted by geographical location,age of participants,outcome,study design,covered area,the methods of exposure assessment,and the length of exposure window.Sensitivity analysis and adjustment for publication bias were performed to test the robustness of the results.ResultsOf 100 studies covered 20 countries worldwide,81 were for short-term and 19 were for long-term exposure.Almost all air pollutants were adversely associated with the risk of HF in both short-and long-term exposure studies.For short-term exposures,we found the risk of HF increased by 1.8%[relative risk(RR)=1.018,95%confidence interval(CI):1.011,1.025]and 1.6%(RR= 1.016,95%CI:1.011,1.020)per 10 μg/m3 increment of PM2.5 and PM10,respectively;HF was also significantly associated with NO2,SO2,CO,but not O3.Positive associations were stronger when exposure was considered over the previous two days(lag 0-1)rather than on the day of exposure only(lag 0).For long-term exposures,there were significant associations between several air pollutants and HF with RR(95%CI)of 1.748(1.112,2.747)per 10 μg/m3 increment in PM2.5,1.212(1.010,1.454)per 10 μg/m3 increment in PM10,and 1.204(1.069,1.356)per 10 ppb increment in NO2,respectively.The effect sizes of associations between most pollutants and HF were greater in low and middle-income countries than those in high-income countries.Sensitivity analysis demonstrated the robustness of our results.ConclusionAvailable evidence highlighted adverse effects of air pollution on HF regardless of short-and long-term exposure.Air pollution is still a prevalent public health issue globally and is called for sustained policies and actions to reduce the burden of HF. |
PDF Full Text Request