title: A feasibility study of the association of exposure to biomass smoke with vascular function, inflammation, and cellular aging.
abstract: BACKGROUND
  Biomass smoke at higher concentrations is associated with respiratory symptoms and, after years of exposure, increased risk of respiratory disorders in adults, but its effects on cardiovascular diseases are not well characterized, particularly compared with other pollution sources like tobacco smoke or traffic.
  
  
  METHODS
  We conducted a cross-sectional study and enrolled 25 women living in rural Sichuan, China. We measured integrated 24-h personal exposure to fine particulate matter (PM2.5) and black carbon, and measured PM2.5 and black carbon in their kitchens. We assessed participants' brachial and central blood pressure and arterial stiffness using pulse wave analysis, and analyzed dried blood spot and buccal cell samples for C-reactive protein and relative telomere length. We also evaluated the difference in these physiological and biomarker measures between individuals with high (≥median) versus low (<median) PM2.5 exposure using multivariate regression.
  
  
  RESULTS
  Geometric mean 24-h PM2.5 and black carbon exposures were 61 µg/m(3) (95% CI: 48, 78) and 3.2 µg/m(3) (95% CI: 2.3, 4.5), respectively. Average kitchen PM2.5 and black carbon concentrations were only moderately correlated with personal exposures (PM2.5: r=0.41; black carbon: r=0.63), although they had similar means. Women in the high and low exposure groups were similar in age, obesity, socioeconomic status, salt intake, and physical activity. Women in the high PM2.5 exposure group had higher mean brachial systolic blood pressure (SBP; difference=4.6 mmHg, 95% CI -7.8, 16.9), central SBP (difference=3.1 mmHg, 95% CI: -8.4, 14.5), central pulse pressure (difference=4.1 mmHg; 95% CI: -4.2, 12.4), and augmentation index (difference=2.8%, 95% CI: -1.6, 7.2). High exposed women had 43% shorter telomere length (95% CI: -113, 28) than that of women in the low exposure group. There were no differences in pulse wave velocity or C-reactive protein between the two exposure groups. None of the results was statistically significant.
  
  
  CONCLUSIONS
  Our results suggest that it is feasible to measure markers of vascular function and biomarkers of inflammation and oxidative stress in field studies of biomass smoke. Although many of the associations were in the expected direction, larger studies would be needed to establish the effects.
authors.affiliation: Department of Building Science, Tsinghua University, Beijing Haidian District, Beijing 100084, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Shan
authors.affiliation: Department of Building Science, Tsinghua University, Beijing Haidian District, Beijing 100084, China. Electronic address: xyang@tsinghua.edu.cn.
authors.forename: Xudong
authors.initials: X
authors.lastname: Yang
authors.affiliation: MRC-PHE Center for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, UK.
authors.forename: Majid
authors.initials: M
authors.lastname: Ezzati
authors.affiliation: International Centre for Circulatory Health, National Heart & Lung Institute, Imperial College London, London, UK; Institute of Cardiovascular Science, University College London, London, UK.
authors.forename: Nishi
authors.initials: N
authors.lastname: Chaturvedi
authors.affiliation: International Centre for Circulatory Health, National Heart & Lung Institute, Imperial College London, London, UK; Institute of Cardiovascular Science, University College London, London, UK.
authors.forename: Emma
authors.initials: E
authors.lastname: Coady
authors.affiliation: International Centre for Circulatory Health, National Heart & Lung Institute, Imperial College London, London, UK; Institute of Cardiovascular Science, University College London, London, UK.
authors.forename: Alun
authors.initials: A
authors.lastname: Hughes
authors.affiliation: Department of Social Medicine and Health Education, School of Public Health, Peking University, Beijing, China.
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Shi
authors.affiliation: College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.affiliation: College of Resources and Environment, University of the Chinese Academy of Sciences, Beijing, China.
authors.forename: Yuanxun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Institute on the Environment, University of Minnesota, St. Paul, MN, USA; Institute for Health and Social Policy and Department of Epidemiology, Biostatistics & Occupational Health, McGill University, 1130 des Pins Avenue Ouest, Montréal, QC, Canada H3A 1A3. Electronic address: jill.baumgartner@mcgill.ca.
authors.forename: Jill
authors.initials: J
authors.lastname: Baumgartner
mesh_terms: D000328:Adult; D000397:Air Pollution / Q000032:analysis*; D015415:Biomarkers; D018533:Biomass; D001794:Blood Pressure / Q000187:drug effects; D016922:Cellular Senescence / Q000187:drug effects*; D002681:China; D003430:Cross-Sectional Studies; D004781:Environmental Exposure; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007249:Inflammation / Q000139:chemically induced*; D052638:Particulate Matter / Q000032:analysis; D012906:Smoke / Q000009:adverse effects*; D053260:Soot / Q000032:analysis; D059289:Vascular Stiffness / Q000187:drug effects*
chemical_list: D015415:Biomarkers; D052638:Particulate Matter; D012906:Smoke; D053260:Soot
keywords: Arterial stiffness; Blood pressure; Household air pollution; Inflammation; Solid fuels; Telomere length