Effects of diesel exhaust inhalation on heart rate variability in human volunteers.

OBJECTIVES Particulate matter (PM) air pollution is associated with alterations in cardiac conductance and sudden cardiac death in epidemiological studies. Traffic-related air pollutants, including diesel exhaust (DE) may be at least partly responsible for these effects. In this experimental study we assessed whether short-term exposure to DE would result in alterations in heart rate variability (HRV), a non-invasive measure of autonomic control of the heart. METHODS In a double-blind, crossover, controlled-exposure study, 16 adult volunteers were exposed (at rest) in randomized order to filtered air (FA) and two levels of diluted DE (100 or 200 microg/m(3) of fine particulate matter) in 2-h sessions. Before, and at four time points after each exposure we assessed HRV. HRV parameters assessed included both time domain statistics (standard deviation of N-N intervals (SDNN), and the square root of the mean of the sum of squared differences between successive N-N intervals (RMSSD)) and frequency domain statistics (high-frequency (HF) power, low-frequency (LF) power, and the LF/HF ratio). RESULTS We observed an effect at 3-h after initiation of DE inhalation on the frequency domain statistics of HRV. DE at 200 microg/m(3) elicited an increase in HF power compared to FA (Delta=0.33; 95% CI: 0.01-0.7) and a decrease in LF/HF ratio (Delta=-0.74; 95% CI: -1.2 to -0.2). The effect of DE on HF power was not consistent among study participants. There was no DE effect on time domain statistics and no significant DE effect on HRV in later time points. CONCLUSIONS We did not observe a consistent DE effect on the autonomic control of the heart in a controlled-exposure experiment in young participants. Efforts are warranted to understand discrepancies between epidemiological and experimental studies of air pollution's impact on HRV.

[1]  S. C. Saxena,et al.  Effects of RR segment duration on HRV spectrum estimation. , 2004, Physiological measurement.

[2]  Thomas J. Smith,et al.  The Association Between Personal Measurements of Environmental Exposure to Particulates and Heart Rate Variability , 2002, Epidemiology.

[3]  J. Bereiter-Hahn,et al.  Effects of cytokines on the contractility of cultured cardiac myocytes. , 1993, International journal of immunopharmacology.

[4]  Thomas J. Smith,et al.  Association of Heart Rate Variability With Occupational and Environmental Exposure to Particulate Air Pollution , 2001, Circulation.

[5]  Delbert J Eatough,et al.  Ambient particulate air pollution, heart rate variability, and blood markers of inflammation in a panel of elderly subjects. , 2004, Environmental health perspectives.

[6]  J. Schwartz,et al.  Ambient particulate air pollution and cardiac arrhythmia in a panel of older adults in Steubenville, Ohio , 2006, Occupational and Environmental Medicine.

[7]  W. Cascio,et al.  Elderly humans exposed to concentrated air pollution particles have decreased heart rate variability , 2003, European Respiratory Journal.

[8]  P. Vokonas,et al.  Effects of Air Pollution on Heart Rate Variability: The VA Normative Aging Study , 2004, Environmental health perspectives.

[9]  W. Cascio,et al.  Altered Heart-Rate Variability in Asthmatic and Healthy Volunteers Exposed to Concentrated Ambient Coarse Particles , 2004, Inhalation toxicology.

[10]  David E. Newby,et al.  Diesel Exhaust Inhalation Causes Vascular Dysfunction and Impaired Endogenous Fibrinolysis , 2005 .

[11]  Wojciech Zareba,et al.  Effects of exposure to ultrafine carbon particles in healthy subjects and subjects with asthma. , 2004, Research report.

[12]  G. Breithardt,et al.  Heart rate variability: standards of measurement, physiological interpretation and clinical use. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. , 1996 .

[13]  F. Dominici,et al.  Fine particulate air pollution and hospital admission for cardiovascular and respiratory diseases. , 2006, JAMA.

[14]  J Schwartz,et al.  Ambient pollution and heart rate variability. , 2000, Circulation.

[15]  J. Hogg,et al.  Cytokines involved in the systemic inflammatory response induced by exposure to particulate matter air pollutants (PM(10)). , 2001, American journal of respiratory and critical care medicine.

[16]  J Schwartz,et al.  Air pollution and incidence of cardiac arrhythmia. , 2000, Epidemiology.

[17]  B. Forsberg,et al.  Ozone enhances the airway inflammation initiated by diesel exhaust. , 2007, Respiratory medicine.

[18]  Richard L. Verrier,et al.  Association of Air Pollution with Increased Incidence of Ventricular Tachyarrhythmias Recorded by Implanted Cardioverter Defibrillators , 2005, Environmental health perspectives.

[19]  I. O'Brien,et al.  Heart rate variability in healthy subjects: effect of age and the derivation of normal ranges for tests of autonomic function. , 1986, British heart journal.

[20]  Ronald W. Williams,et al.  Particulate matter exposure in cars is associated with cardiovascular effects in healthy young men. , 2004, American journal of respiratory and critical care medicine.

[21]  Joel Schwartz,et al.  Focused Exposures to Airborne Traffic Particles and Heart Rate Variability in the Elderly , 2007, Epidemiology.

[22]  Fernando Costa,et al.  Diagnosis and management of the metabolic syndrome: an American Heart Association/National Heart, Lung, and Blood Institute scientific statement. , 2006, Current opinion in cardiology.

[23]  I. Romieu,et al.  Omega-3 fatty acid prevents heart rate variability reductions associated with particulate matter. , 2005, American journal of respiratory and critical care medicine.

[24]  A. Ghio,et al.  Effect of ozone on diesel exhaust particle toxicity in rat lung. , 2000, Toxicology and applied pharmacology.

[25]  D. Nowak,et al.  Heart rate variability, hemostatic and acute inflammatory blood parameters in healthy adults after short-term exposure to welding fume , 2007, International archives of occupational and environmental health.

[26]  A. Nel,et al.  The role of particulate pollutants in pulmonary inflammation and asthma: evidence for the involvement of organic chemicals and oxidative stress , 2001, Current opinion in pulmonary medicine.

[27]  J. Kaufman,et al.  Association between short term exposure to fine particulate matter and heart rate variability in older subjects with and without heart disease , 2005, Thorax.

[28]  David E Newby,et al.  Diesel Exhaust Inhalation Causes Vascular Dysfunction and Impaired Endogenous Fibrinolysis , 2005, Circulation.

[29]  R W Barnes,et al.  Age, race, and sex differences in autonomic cardiac function measured by spectral analysis of heart rate variability--the ARIC study. Atherosclerosis Risk in Communities. , 1995, The American journal of cardiology.

[30]  D. Dockery,et al.  Increased Particulate Air Pollution and the Triggering of Myocardial Infarction , 2001, Circulation.

[31]  J. Schwartz,et al.  Increased Risk of Paroxysmal Atrial Fibrillation Episodes Associated with Acute Increases in Ambient Air Pollution , 2005, Environmental health perspectives.

[32]  Michael Lipsett,et al.  The Effects of Components of Fine Particulate Air Pollution on Mortality in California: Results from CALFINE , 2006, Environmental health perspectives.

[33]  Chang-Chuan Chan,et al.  Personal Exposure to Submicrometer Particles and Heart Rate Variability in Human Subjects , 2004, Environmental health perspectives.

[34]  W. Haefeli,et al.  Evidence for activation of the sympathetic nervous system by recombinant human interleukin-1 beta in humans. , 1993, Journal of immunotherapy with emphasis on tumor immunology : official journal of the Society for Biological Therapy.

[35]  J Schwartz,et al.  Traffic related pollution and heart rate variability in a panel of elderly subjects , 2005, Thorax.

[36]  J. Schwartz,et al.  Heart rate variability associated with particulate air pollution. , 1999, American heart journal.

[37]  Mika P. Tarvainen,et al.  Software for advanced HRV analysis , 2004, Comput. Methods Programs Biomed..

[38]  Zhi‐Jie Zheng,et al.  Association of higher levels of ambient criteria pollutants with impaired cardiac autonomic control: a population-based study. , 2004, American journal of epidemiology.

[39]  Mika P. Tarvainen,et al.  An advanced detrending method with application to HRV analysis , 2002, IEEE Transactions on Biomedical Engineering.

[40]  Ronald W. Williams,et al.  Daily variation of particulate air pollution and poor cardiac autonomic control in the elderly. , 1999, Environmental health perspectives.