title: Gender-specific differences of interaction between obesity and air pollution on stroke and cardiovascular diseases in Chinese adults from a high pollution range area: A large population based cross sectional study.
abstract: BACKGROUND
  Little information exists regarding the interaction effects of obesity with long-term air pollution exposure on cardiovascular diseases (CVDs) and stroke in areas of high pollution. The aim of the present study is to examine whether obesity modifies CVD-related associations among people living in an industrial province of northeast China.
  
  
  METHODS
  We studied 24,845 Chinese adults, aged 18 to 74 years old, from three Northeastern Chinese cities in 2009 utilizing a cross-sectional study design. Body weight and height were measured by trained observers. Overweight and obesity were defined as a body mass index (BMI) between 25-29.9 and ≥30 kg/m(2), respectively. Prevalence rate and related risk factors of cardiovascular and cerebrovascular diseases were investigated by a questionnaire. Three-year (2006-2008) average concentrations of particulate matter (PM10), sulfur dioxide (SO2), nitrogen dioxides (NO2), and ozone (O3) were measured by fixed monitoring stations. All the participants lived within 1 km of air monitoring sites. Two-level logistic regression (personal level and district-specific pollutant level) was used to examine these effects, controlling for covariates.
  
  
  RESULTS
  We observed significant interactions between exposure and obesity on CVDs and stroke. The associations between annual pollutant concentrations and CVDs and stroke were strongest in obese subjects (OR 1.15-1.47 for stroke, 1.33-1.59 for CVDs), less strong in overweight subjects (OR 1.22-1.35 for stroke, 1.07-1.13 for CVDs), and weakest in normal weight subjects (OR ranged from 0.98-1.01 for stroke, 0.93-1.15 for CVDs). When stratified by gender, these interactions were significant only in women.
  
  
  CONCLUSIONS
  Study findings indicate that being overweight and obese may enhance the effects of air pollution on the prevalence of CVDs and stroke in Northeastern metropolitan China. Further studies will be needed to investigate the temporality of BMI relative to exposure and onset of disease.
authors.affiliation: Guangzhou Key Laboratory of Environmental Pollution and Health Risk Assessment, Department of Environmental and Occupational Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, PR China.
authors.forename: Xiao-Di
authors.initials: XD
authors.lastname: Qin
authors.affiliation: Department of Epidemiology, College for Public Health and Social Justice, Saint Louis University, Saint Louis, MO 63104, USA.
authors.forename: Zhengmin
authors.initials: Z
authors.lastname: Qian
authors.affiliation: School of Social Work, College for Public Health and Social Justice, Saint Louis University, Saint Louis, MO 63104, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Vaughn
authors.affiliation: Department of Epidemiology, College for Public Health and Social Justice, Saint Louis University, Saint Louis, MO 63104, USA.
authors.forename: Edwin
authors.initials: E
authors.lastname: Trevathan
authors.affiliation: Department of Environmental and Occupational Health, College for Public Health and Social Justice, Saint Louis University, Saint Louis, MO 63104, USA.
authors.forename: Brett
authors.initials: B
authors.lastname: Emo
authors.affiliation: Facuty of Health, School of Public Health and Social Work, Queensland University of Technology, Kelvin Grove, QLD 4059, Australia.
authors.forename: Gunther
authors.initials: G
authors.lastname: Paul
authors.affiliation: Department of Ambient Air Pollution Monitor, Shenyang Environmental Monitoring Center, Shenyang 110004, China.
authors.forename: Wan-Hui
authors.initials: WH
authors.lastname: Ren
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Sun Yat-sen University, Guangzhou 510080, PR China.
authors.forename: Yuan-Tao
authors.initials: YT
authors.lastname: Hao
authors.affiliation: Guangzhou Key Laboratory of Environmental Pollution and Health Risk Assessment, Department of Environmental and Occupational Health, School of Public Health, Sun Yat-sen University, Guangzhou 510080, PR China. Electronic address: donggh5@mail.sysu.edu.cn.
authors.forename: Guang-Hui
authors.initials: GH
authors.lastname: Dong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000032:analysis; D000397:Air Pollution / Q000706:statistics & numerical data*; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D002681:China; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009585:Nitrogen Dioxide / Q000032:analysis; D009765:Obesity; D010126:Ozone / Q000032:analysis; D052638:Particulate Matter / Q000032:analysis; D012307:Risk Factors; D012737:Sex Factors; D020521:Stroke / Q000453:epidemiology*; D013458:Sulfur Dioxide / Q000032:analysis; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D013458:Sulfur Dioxide; D010126:Ozone; D009585:Nitrogen Dioxide
keywords: Air pollution; Cardiovascular diseases; Interaction effect; Obesity; Stroke