title: Personal coronary risk profiles modify autonomic nervous system responses to air pollution.
abstract: OBJECTIVE
  We investigated whether PM2.5-mediated autonomic modulation depends on individual coronary risk profiles.
  
  
  METHODS
  Five-minute average heart rate (HR) and heart rate variability (HRV, including standard deviation of normal-to-normal intervals [SDNN], square root of the mean squared differences of successive NN intervals [rMSSD], high frequency [HF]) were measured from 24-hour ambulatory electrocardiograms, and personal PM(2.5) exposures were monitored in a prospective study of 10 male boilermakers (aged 34.3 +/- 8.1 years). We used the Framingham score to classify individuals into low (score = 1-3) and high (score = 5-6) risk categories. Mixed-effect models were used for statistical analyses.
  
  
  RESULTS
  Each 1-mg/m(3) increase in the preceding 4-hour moving average PM(2.5) was associated with HR increase (5.3 beats/min) and HRV reduction (11.7%, confidence interval [CI] = 6.2-17.1% for SDNN; 11.1%, CI = 3.1-19.1% for rMSSD; 16.6%, CI = 1.5-31.7% for HF). Greater responses (2- to 4-fold differences) were observed in high-risk subjects than in low-risk subjects.
  
  
  CONCLUSIONS
  Our study suggests that adverse autonomic responses to metal particulate are aggravated in workers with higher coronary risk profiles.
authors.affiliation: Harvard School of Public Health, 655 Huntington Avenue, Boston, MA 02115, USA.
authors.forename: Jiu-Chiuan
authors.initials: JC
authors.lastname: Chen
authors.forename: Peter H
authors.initials: PH
authors.lastname: Stone
authors.forename: Richard L
authors.initials: RL
authors.lastname: Verrier
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Nearing
authors.forename: Gail
authors.initials: G
authors.lastname: MacCallum
authors.forename: Jee-Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Robert F
authors.initials: RF
authors.lastname: Herrick
authors.forename: Jinhong
authors.initials: J
authors.lastname: You
authors.forename: Haibo
authors.initials: H
authors.lastname: Zhou
authors.forename: David C
authors.initials: DC
authors.lastname: Christiani
mesh_terms: D000328:Adult; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D001341:Autonomic Nervous System / Q000502:physiology*; D002318:Cardiovascular Diseases; D015331:Cohort Studies; D015716:Electrocardiography, Ambulatory; D006306:Health Surveys; D006339:Heart Rate; D006801:Humans; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects*; D052638:Particulate Matter / Q000009:adverse effects*; D012307:Risk Factors; D014896:Welding
chemical_list: D000395:Air Pollutants, Occupational; D052638:Particulate Matter