Health & Environmental Research Online (HERO)


Print Feedback Export to File
2616786 
Journal Article 
Abstract 
Air pollution is associated with increased atrial arrhythmias in patients with implanted cardioverter defibrillators 
Schwartz, J; Coull, B; Gold, DR; Dockery, D; Laden, F; Link, M 
2010 
Yes 
American Journal of Respiratory and Critical Care Medicine
ISSN: 1073-449X
EISSN: 1535-4970 
181 
A1713 
English 
WOS:000208771000713 
is part of a larger document 3452678 Proceedings of the American Thoracic Society 2010 International Conference, May 14-19, 2010, New Orleans
Introduction: Implanted cardioverter defibrillators (ICD) monitor and treat ventricular arrhythmias. These devices also provide electrocardiographic records of the dates and times of ventricular and atrial arrhythmias. We examined the effects of ambient air pollution on cardiac arrhythmias among a cohort of dual chamber ICD patients followed at the Tufts Medical Center in Boston.

Methods: We collected data in an ongoing prospective cohort study of ICD patients enrolled since November 2006. Dates and times of detected arrhythmias were downloaded during the patients’ regular follow-up visits. Arrhythmias were categorized into ventricular and supra-ventricular (SVT) events (with sub-categories “atrial fibrillation”, “atrial flutter”, and “atrial tachycardia”) by review of electrograms. This current analysis focuses on SVTs. If time periods between two successive episodes were shorter than 60 minutes, these episodes were regarded as part of the same arrhythmia represented by the onset of the sequence. Fine particle data, gaseous pollutants and meteorological data were available on an hourly basis. We analyzed the association between air pollution and the onset of arrhythmias with a case-crossover approach. Cardiac events were matched with control time periods by month and day of the week. Air pollution exposure was included as 6-hour, 12-hour and 24-hour moving averages. Risks of SVTs associated with air pollution were estimated with conditional logistic regression, adjusted for temperature and relative humidity, and reported as odds ratios (OR) for an interquartile range increase in exposure.

Results: A total of 93 patients with a mean follow-up time of 1.4 years had 2279 episodes of SVTs (956 atrial fibrillations). Increased risks of atrial fibrillation were associated with 6-hour mean PM2.5 (OR 1.21 for a 7.8 μg/m^3 increase, 95% CI 0.99 to 1.46) and black carbon (OR=1.33 for an 0.7 μg/m^3 increase, CI 1.06 to 1.66), and were not associated with sulfate (OR=1.01 for an 1.9 μg/m^3 increase, CI 0.90 to 1.13). The ORs for other atrial arrhythmias were estimated as 1.26 (1.08 to 1.49) for PM2.5, 1.21 (1.09 to 1.34) for sulfate, and 1.04 (0.87 to 1.25) for black carbon. Results for the 12-h and 24-h exposure metrics were similar. We found no associations between ambient gases and SVTs.

Conclusions: The results of this interim analysis suggest that particle exposure is associated with SVTs, with traffic particles primarily associated with atrial fibrillation and secondary particles with other atrial events. This increased risk of SVTs may account for a portion of the increased cardiovascular mortality observed with air pollution. 
American Thoracic Society 2010 International Conference 
New Orleans, LA 
May 14-19, 2010