title: Vascular function, inflammation, and variations in cardiac autonomic responses to particulate matter among welders.
abstract: Patients with health conditions associated with impaired vascular function and inflammation may be more susceptible to the adverse health effects of fine particulate (particulate matter with a mass median aerodynamic diameter of </=2.5 mum (PM(2.5))) exposure. In 2006, the authors conducted a panel study to investigate directly whether vascular function and inflammation (assessed by C-reactive protein) modify PM(2.5)-associated reductions in heart rate variability among 23 young male workers (mean age, 40 years) from Massachusetts. Concurrent 24-hour ambulatory electrocardiogram and personal PM(2.5) exposure information was collected over a total of 36 person-days, including either or both welding and nonwelding days. Linear mixed models were used to examine the 5-minute standard deviation of normal-to-normal intervals (SDNN) in relation to the moving PM(2.5) averages in the preceding 1-4 hours. C-reactive protein levels and 3 measures of vascular function (augmentation index, mean arterial pressure, and pulse pressure) were determined at baseline. The authors observed an inverse association between the 1-hour PM(2.5) and 5-minute SDNN. Greater SDNN declines were observed among those with C-reactive protein (P(interaction) < 0.001) and augmentation index (P = 0.06) values at or above the 75th percentile and pulse pressure values below the 75th percentile (P < 0.001). Systemic inflammation and poorer vascular function appear to aggravate particle-related declines in heart rate variability among workers.
authors.affiliation: 665 Huntington Avenue, Boston, MA 02115, USA. sfang@hsph.harvard.edu
authors.forename: Shona C
authors.initials: SC
authors.lastname: Fang
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Cavallari
authors.forename: Ellen A
authors.initials: EA
authors.lastname: Eisen
authors.forename: Jiu-Chiuan
authors.initials: JC
authors.lastname: Chen
authors.forename: Murray A
authors.initials: MA
authors.lastname: Mittleman
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; D001794:Blood Pressure; D002097:C-Reactive Protein / Q000032:analysis; D015716:Electrocardiography, Ambulatory; D006321:Heart / Q000294:innervation; D006339:Heart Rate; D006801:Humans; D007249:Inflammation; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D052638:Particulate Matter / Q000009:adverse effects*; D011673:Pulsatile Flow; D014896:Welding
chemical_list: D000395:Air Pollutants, Occupational; D052638:Particulate Matter; D002097:C-Reactive Protein