title: Effects of Personal Exposure to Ambient Fine Particulate Matter on Acute Change in Nocturnal Heart Rate Variability in Subjects Without Overt Heart Disease.
abstract: The immediate effect within minutes to hours of personal exposure to ambient fine particulate matter (PM2.5) on cardiac autonomic function is limited, particularly at night. Our study aimed to assess the lagged association between personal exposure to PM2.5 and nocturnal heart rate variability. Repeated measures panel study among 21 community adults recruited from a local health clinic during the period of March 1, 2004, to August 31, 2004, in Boston, Massachusetts, in the United States. Ambulatory electrocardiogram and continuous monitoring of personal exposure to PM2.5 and were measured for up to 2 consecutive days. We calculated 5-minute time-specific average PM2.5 exposure for each participant. Mixed-effects models were fit for 5-minute SD of normal-to-normal intervals (SDNN) and 5-minute heart rate in relation to 5-minute PM2.5 exposure lagged in 5-minute intervals up to 4 hours. We found an 8.4% decrease in nocturnal SDNN (95% confidence interval [CI] -11.3% to -5.5%) and a 1.9% increase in nighttime heart rate (95% CI 1.1% to 2.7%) for an interquartile range increase in PM2.5 (13.6 μg/m(3)), after adjusting for confounders. Significant decreases in nocturnal SDNN associated with PM2.5 exposure occurred within 2.5 hours. The largest decrease in nocturnal SDNN of -12.8% (95% CI -16.4 to -9.1%) that was associated with PM2.5 exposure was found with a lag of 25 minutes. Rapid changes in nocturnal heart rate variability associated with personal PM2.5 exposure occurred within the previous 2.5 hours, with the largest effects at 25 minutes, suggesting immediate cardiac autonomic effects of fine particulate exposure.
authors.affiliation: Department of Environmental Health, Environmental and Occupational Medicine and Epidemiology Program, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
authors.forename: Mi-Sun
authors.initials: MS
authors.lastname: Lee
authors.affiliation: Department of Environmental Health, Environmental and Occupational Medicine and Epidemiology Program, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
authors.forename: Ki-Do
authors.initials: KD
authors.lastname: Eum
authors.affiliation: Department of Environmental Health, Environmental and Occupational Medicine and Epidemiology Program, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
authors.forename: Ema G
authors.initials: EG
authors.lastname: Rodrigues
authors.affiliation: Department of Environmental Health, Environmental and Occupational Medicine and Epidemiology Program, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Colden Corporation, New York, New York.
authors.forename: Shannon R
authors.initials: SR
authors.lastname: Magari
authors.affiliation: Department of Environmental Health, Environmental and Occupational Medicine and Epidemiology Program, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; New England Research Institutes, Inc., Watertown, Massachusetts.
authors.forename: Shona C
authors.initials: SC
authors.lastname: Fang
authors.affiliation: Upham's Corner Health Center, Boston University School of Medicine, Boston, Massachusetts.
authors.forename: Geoffrey A
authors.initials: GA
authors.lastname: Modest
authors.affiliation: Department of Environmental Health, Environmental and Occupational Medicine and Epidemiology Program, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts. Electronic address: dchris@hsph.harvard.edu.
authors.forename: David C
authors.initials: DC
authors.lastname: Christiani
mesh_terms: D000328:Adult; D000368:Aged; D001341:Autonomic Nervous System / Q000187:drug effects / Q000503:physiopathology*; D002940:Circadian Rhythm; D015716:Electrocardiography, Ambulatory; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D052638:Particulate Matter / Q000009:adverse effects*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D052638:Particulate Matter