title: Main air pollutants and diabetes-associated mortality: a systematic review and meta-analysis.
abstract: OBJECTIVE
  Exposure to high levels of air pollutants may be linked to diabetes-associated mortality, but the associations remain unclear. To assess the associations between main air pollutants and diabetes-associated mortality, a systematic review and meta-analysis was performed.
  
  
  METHODS
  PubMed, Embase and Web of Science were searched for studies investigating the associations between increments in gaseous (nitrogen dioxide (NO2), sulphur dioxide, ozone (O3) and carbon monoxide) and particulate matter (PM; diameter<2.5 μm (PM2.5) or <10 μm (PM10)) air pollutants and diabetes-associated mortality. Using a random-effects model, relative risks (RRs) and 95% CIs were calculated per interquartile range (IQR) increment or per 10 μg/m3 increment in pollutant concentrations.
  
  
  RESULTS
  Out of 925 identified articles, 36 were reviewed in depth and 12 studies from 13 articles satisfying the inclusion criteria (five time-series, five case-crossovers and two cohorts) were finally included. Increased risk of diabetes-associated mortality was associated with higher levels of PM2.5 (per 10 μg/m3: RR=1.123, 95% CI 1.036-1.217, P=0.005, I2=96.1%), PM10 (per 10 μg/m3: RR=1.008, 95% CI 1.004-1.013, P<0.001, I2=0%), NO2 (per 10 μg/m3: RR=1.024, 95% CI 1.007-1.041, P=0.006, I2=49.7%) and O3 (per IQR increment: RR=1.065, 95% CI 1.017-1.115, P=0.007, I2=0.0%). No obvious risk of publication bias was observed.
  
  
  CONCLUSIONS
  Exposure to high levels of air pollutants is significantly associated with an increased risk of diabetes-associated mortality.
authors.affiliation: Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China.
authors.forename: Chengqian
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Fang
authors.affiliation: Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China.
authors.forename: Donghua
authors.initials: D
authors.lastname: Xu
authors.affiliation: Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China nlwang@126.com robin.wangqy@gmail.com.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China.
authors.forename: Shihua
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China.
authors.forename: Shengli
authors.initials: S
authors.lastname: Yan
authors.affiliation: Department of EndocrinologyThe Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, ChinaDepartment of RheumatologyFirst Affiliated Hospital of Nanjing Medical University, Nanjing 210029, ChinaEssencemed ClinicWeifang 261000, China nlwang@126.com robin.wangqy@gmail.com.
authors.forename: Yangang
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D002318:Cardiovascular Diseases / Q000209:etiology / Q000401:mortality; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000401:mortality*; D004781:Environmental Exposure / Q000009:adverse effects / Q000706:statistics & numerical data; D006801:Humans; D009585:Nitrogen Dioxide / Q000633:toxicity; D052638:Particulate Matter / Q000633:toxicity
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D009585:Nitrogen Dioxide