NASA Technical Reports Server (NTRS) 20070021530: Cardiac Autonomic Effects of Acute Exposures to Airborne Particulates in Men and Women

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612.15 Cardiac Autonomic Effects of Acute Exposures to Airborne Particulates in Men and Women 1211331M.S. Howarth, T.T. Schlegel, C.F. Knapp, A.R. Patwardhan, R.A. Jenkins, R.H. Ilgnerand J.M. Evans 123Center for Biomedical Engineering, University of Kentucky; NASA Johnson Space Center, Houston, TX; Oak Ridge National Laboratory, TN meanNN IntervalENVIRONMENTAL CHAMBER CONDITIONS:SUMMARY OF RESULTS:meanNNParticulate concentration, CO, CO, and TemperatureStatistics:Mean +/- SEMStatistical testing (SAS 9.1) used a mixed analysis of variance 2(ANOVA), composed of one between subject factor (gender) and twowithin factors 1000.00(exposure stage [5 stages] and exposure species [4 species]). Post hoc testing 3Particulate Concentration(ug/m)Temperature(deg F)consisted of least significant difference comparisons between desired states. 950.00Concentration Overlayp<0.05 was considered to be significant. Temperature Overlay1800RIGHT72.0900.00ETS MaleETS Female1600Compared to pre-exposure (p<0.0002) and sham exposure (p<0.047), male heart Oil MaleOil Femalesrates were elevated during early ETS post-exposure.850.00m71.5Wood Male1400Wood FemaleSham MaleBELOWSham Female800.00120071.0The short-term fractal scaling exponent (Alpha-1) and the ratio of low frequency to high frequency Heart Rate Variability (HRV) powers (LF/HF, a purported 1000ETS750.003ETSmOilsympathetic index) were both higher in males (p<0.017 and p<0.05, respectively) F/gOilgWoodu70.5edWoodwhereas approximate entropy (ApEn) and HF/(LF+HF) (a purported Sham800Sham Control 256 Exposure 256 Exposure 512 Flush 256 Flush 512parasympathetic index) were both lower in males (p<0.036, and p<0.044, 700.00respectively). 60070.0Ratio of LF/HF Spectral PowerShort-term Fractal Scaling Exponent (Alpha 1)400LF/HFAlpha 1Mean +/- SEM Mean +/- SEM69.52001.601.40 01.5069.00501001502002503000501001502002501.30Control Exposure FlushRed –ETSControl Exposure Flush1.40Gold –C. OilCO(ppm)Carbon MonoxideCO (ppm)Carbon Dioxide1.20Brown –Wood2ETS MaleETS Male1.30ETS FemaleETS FemaleCO OverlayCO2 OverlayOil MaleOil MaleBlue -ShamOil FemaleOil Female1.201.104.5Wood MaleWood MaleWood FemaleWood FemaleSham MaleSham Male8001.10Sham FemaleSham Female41.00 7001.003.50.900.906003 Control 256 Exposure 256 Exposure 512 Flush 256 Flush 512 Control 256 Exposure 256 Exposure 512 Flush 256 Flush 5120.800.805002.5Red –ETSETSCircles –mETSmOilpMaleppWoodGold –C. OilRatio of HF/(LF+HF) Spectral PowerpWoodApproximate Entropy (ApEn)4002ShamDiamonds -Brown –WoodFemaleApEnHF/(LF+HF)Mean +/- SEM300Blue -ShamMean +/- SEM1.5 1.200.5120011.150.50 0.51000.491.10 0.4801.050050100150200250300ETS Male050100150200250ETS MaleControl Exposure FlushETS Female0.47ETS FemaleControl Exposure Flush1.00Oil MaleOil MaleOil FemaleOil Female0.46Wood MaleWood MaleMETHODS OF PRODUCING AEROSOL PARTICULATE STIMULI:0.95Wood FemaleWood FemaleSham MaleSham Male0.45Sham FemaleSham FemaleTwo glove boxes (One for ETS and Wood) and (One for Oil and ShamWater Vapor)0.900.44 0.850.43 0.800.42 Control 256 Exposure 256 Exposure 512 Flush 256 Flush 512 Control 256 Exposure 256 Exposure 512 Flush 256 Flush 5120.750.41 CONCLUSION:Our data suggest that, in addition to tonic HRV gender differences, cardiac responses to some acute airborne particulates are gender related. FUTURE PERSPECTIVE:The first author is awaiting notification from the American Heart Association (AHA) in regards to a Pre-Doctoral Fellowship proposal to conduct several new and/or emerging advanced ECG analysis techniques from collaborative efforts with NASA. The techniques include: 1) parameters obtained via Signal Averaged ECG (SAECG), including high frequency QRS (HF-QRS) ECG, the ventricular gradient, and the variability of the ventricular gradient; 2) several parameters of beat-to-beat QT interval variability (QTV); and 3) several parameters ofT-wave morphology (TWM) derived from singular value decomposition (SVD). ACKNOWLEDGEMENTS:The authors would like to greatly thank Helena Truszczynska(University of Kentucky) for statistical consultation. This study was supported by Philip Morris USA. REFERENCES: Pope CA, EatoughDJ, Gold DR, Pang Y, Nielsen KR, NathP, VerrierRL, and KannerRE (2001). Acute exposure to environmental tobacco Automatic smoking machines (2 cigarettes) and bricks for Frying pans for cooking oil and water vaporsmoke and heart rate variability. Environ Health Perspect109(7):711-6.which to burn cedar wood pieces
BIOMEDICAL ENGINEERING ABSTRACT:The aim of this research was to investigate cardiac autonomic changes associated with acute exposures to airborne particulates.MethodsHigh fidelity 12-lead ECG (CardioSoft, Houston, TX) was acquired from 19 (10 male / 9 female) non-smoking volunteers (age 33.6 +/-6.6 yrs) during 10 minutes pre-exposure, exposure and post-exposure to environmental tobacco smoke (ETS), cooking oil fumes, wood smoke and sham (water vapor). To control exposure levels, noise, subject activity, and temperature, all studies were conducted inside an environmental chamber. ResultsThe short-term fractal scaling exponent (Alpha-1) and the ratio of low frequency to high frequency Heart Rate Variability (HRV) powers (LF/HF, a purported sympathetic index) were both higher in males (p<0.017 and p<0.05, respectively) whereas approximate entropy (ApEn) and HF/(LF+HF) (a purported parasympathetic index) were both lower in males (p<0.036, and p<0.044, respectively). Compared to pre-exposure (p<0.0002) and sham exposure (p<0.047), male heart rates were elevated during early ETS post-exposure. Our data suggest that, in addition to tonic HRV gender differences, cardiac responses to some acute airborne particulates are gender related. Supported by Philip Morris USA. BACKGROUND:Exposure to environmental tobacco smoke has been found to result in potentially harmful changes in autonomic balance (heart rate variability, HRV) controlling heart rates of nonsmoking volunteers sitting for two hours in airport smoking rooms (Pope, 2001) METHODS: Subjects:19 (10 male / 9 female) non-smoking volunteers (age 33.6 +/-6.6 yrs) Protocol:Seated subjects for 10 minutes pre-exposure, exposure and post-exposure conducted inside an environmental chamber in order to control exposure levels, noise, subject activity and temperature Stimuli:Environmental tobacco smoke (ETS), cooking oil fumes, wood smoke and sham (water vapor) Measurements:High-fidelity 12-lead ECG (CardioSoft, Houston, TX). HRV was calculated using N=256 beats (sliding window configuration). Study PI’s with instrumentation inside of the environmental chamber