title: Ambient Air Pollutants Have Adverse Effects on Insulin and Glucose Homeostasis in Mexican Americans.
abstract: Recent studies suggest that air pollution plays a role in type 2 diabetes (T2D) incidence and mortality. The underlying physiological mechanisms have yet to be established. We hypothesized that air pollution adversely affects insulin sensitivity and secretion and serum lipid levels.
  
  
  
  Participants were selected from BetaGene (n = 1,023), a study of insulin resistance and pancreatic β-cell function in Mexican Americans. All participants underwent DXA and oral and intravenous glucose tolerance tests and completed dietary and physical activity questionnaires. Ambient air pollutant concentrations (NO2, O3, and PM2.5) for short- and long-term periods were assigned by spatial interpolation (maximum interpolation radius of 50 km) of data from air quality monitors. Traffic-related air pollution from freeways (TRAP) was estimated using the dispersion model as NOx. Variance component models were used to analyze individual and multiple air pollutant associations with metabolic traits.
  
  
  
  Short-term (up to 58 days cumulative lagged averages) exposure to PM2.5 was associated with lower insulin sensitivity and HDL-to-LDL cholesterol ratio and higher fasting glucose and insulin, HOMA-IR, total cholesterol, and LDL cholesterol (LDL-C) (all P ≤ 0.036). Annual average PM2.5 was associated with higher fasting glucose, HOMA-IR, and LDL-C (P ≤ 0.043). The effects of short-term PM2.5 exposure on insulin sensitivity were largest among obese participants. No statistically significant associations were found between TRAP and metabolic outcomes.
  
  
  
  Exposure to ambient air pollutants adversely affects glucose tolerance, insulin sensitivity, and blood lipid concentrations. Our findings suggest that ambient air pollutants may contribute to the pathophysiology in the development of T2D and related sequelae.
authors: Division of Environmental Health, Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
authors: Zhanghua
authors: Z
authors: Chen
authors: Division of Environmental Health, Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA Department of Psychiatry, Kern Medical Center, Bakersfield, CA.
authors: Muhammad T
authors: MT
authors: Salam
authors: Division of Environmental Health, Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA Department of Public Health, California State University, Los Angeles, CA.
authors: Claudia
authors: C
authors: Toledo-Corral
authors: Division of Biostatistics, Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA Department of Physiology and Biophysics, Keck School of Medicine of the University of Southern California, Los Angeles, CA Diabetes and Obesity Research Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
authors: Richard M
authors: RM
authors: Watanabe
authors: Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, CA.
authors: Anny H
authors: AH
authors: Xiang
authors: Department of Physiology and Biophysics, Keck School of Medicine of the University of Southern California, Los Angeles, CA Diabetes and Obesity Research Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA Division of Diabetes and Endocrinology, Department of Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
authors: Thomas A
authors: TA
authors: Buchanan
authors: Division of Environmental Health, Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
authors: Rima
authors: R
authors: Habre
authors: Division of Environmental Health, Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
authors: Theresa M
authors: TM
authors: Bastain
authors: Sonoma Technology, Inc., Petaluma, CA.
authors: Fred
authors: F
authors: Lurmann
authors: Spatial Sciences Institute, University of Southern California, Los Angeles, CA.
authors: John P
authors: JP
authors: Wilson
authors: Division of Diabetes and Endocrinology, Department of Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
authors: Enrique
authors: E
authors: Trigo
authors: Division of Environmental Health, Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA gillilan@usc.edu.
authors: Frank D
authors: FD
authors: Gilliland
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000633:toxicity*; D001786:Blood Glucose / Q000378:metabolism*; D015992:Body Mass Index; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000453:epidemiology*; D005260:Female; D006706:Homeostasis; D006801:Humans; D015994:Incidence; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D008297:Male; D017058:Mexican Americans; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000453:epidemiology*; D052638:Particulate Matter / Q000633:toxicity; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007328:Insulin; D052638:Particulate Matter