title: The association of pulmonary function with carotid atherosclerosis in older Chinese: Guangzhou Biobank Cohort Study-CVD Subcohort.
abstract: BACKGROUND
  Evidence describing the association between pulmonary function and carotid atherosclerosis has been inconclusive and the role of smoking in this association is unclear. We therefore examined this association in the Guangzhou Biobank Cohort Study-CVD Subcohort.
  
  
  METHODS
  Common carotid artery (CCA) intima-media thickness (IMT) and carotid plaques were measured by B-mode ultrasonography and lung function by spirometry using a turbine flowmeter. Chronic obstructive pulmonary disease (COPD) was defined as the ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) of less than 0.70. Predicted FEV1 and FVC were derived using equations for Chinese.
  
  
  RESULTS
  Of 1625 participants aged 50 + years, 382 (23.5%) had evidence of carotid plaque. The mean CCA-IMT was higher in those with COPD than those without (0.82 ± 0.29 mm versus 0.76 ± 0.31 mm, P = 0.02). We found no evidence that the association of pulmonary function with CCA-IMT varied by smoking status (P values interaction: 0.23-0.83). After adjustment for a wide range of potential confounders, the increased risks of thickened CCA-IMT (CCA-IMT ≥1.0 mm) in those with COPD became marginally nonsignificant (adjusted odds ratio (OR) 1.45, 95% confidence interval (CI) 0.91-2.29; P = 0.12). Compared to those in the highest tertile, participants in the lowest tertile of FEV1 observed to predicted ratio had increased risk of thickened CCA-IMT (adjusted OR 2.18, 95% CI 1.42-3.34) and carotid plaque (adjusted OR 1.50, 95% CI 1.08-2.09), while participants in the lowest tertile of FVC observed to predicted ratio had increased risk of thickened CCA-IMT (adjusted OR 2.29, 95% CI 1.46-3.58), but the adjusted OR for carotid plaque was marginally nonsignificant (adjusted OR 1.29, 95% CI 0.93-1.80; P = 0.13).
  
  
  CONCLUSIONS
  Independent of smoking status, poor pulmonary function was dose-dependently associated with carotid atherosclerosis in older Chinese. (281 words).
authors.affiliation: Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China; Guangzhou No.12 Hospital, Guangzhou, Guangdong, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Pan
authors.affiliation: School of Public Health, The University of Hong Kong, Hong Kong, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Xu
authors.affiliation: Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China. Electronic address: caishaox@fimmu.com.
authors.forename: Shao Xi
authors.initials: SX
authors.lastname: Cai
authors.affiliation: Guangzhou No.12 Hospital, Guangzhou, Guangdong, China. Electronic address: jcqianggz@163.com.
authors.forename: Chao Qiang
authors.initials: CQ
authors.lastname: Jiang
authors.affiliation: Public Health, Epidemiology, and Biostatistics, University of Birmingham, Birmingham, UK.
authors.forename: Kar Keung
authors.initials: KK
authors.lastname: Cheng
authors.affiliation: Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
authors.forename: Hai Jin
authors.initials: HJ
authors.lastname: Zhao
authors.affiliation: Guangzhou No.12 Hospital, Guangzhou, Guangdong, China.
authors.forename: Wei Sen
authors.initials: WS
authors.lastname: Zhang
authors.affiliation: Guangzhou No.12 Hospital, Guangzhou, Guangdong, China.
authors.forename: Ya Li
authors.initials: YL
authors.lastname: Jin
authors.affiliation: Guangzhou No.12 Hospital, Guangzhou, Guangdong, China.
authors.forename: Jie Ming
authors.initials: JM
authors.lastname: Lin
authors.affiliation: Public Health, Epidemiology, and Biostatistics, University of Birmingham, Birmingham, UK.
authors.forename: G Neil
authors.initials: GN
authors.lastname: Thomas
authors.affiliation: School of Public Health, The University of Hong Kong, Hong Kong, China.
authors.forename: Tai Hing
authors.initials: TH
authors.lastname: Lam
mesh_terms: D000367:Age Factors; D000368:Aged; D018070:Biological Specimen Banks; D002340:Carotid Artery Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging; D059168:Carotid Intima-Media Thickness; D016009:Chi-Square Distribution; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004739:England; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016015:Logistic Models; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D018570:Risk Assessment; D012307:Risk Factors; D013147:Spirometry; D014797:Vital Capacity
keywords: Carotid atherosclerosis; Chronic obstructive pulmonary disease; Intimal-medial thickness; Pulmonary function