Exposure to particulate matter PM has been associated with an increase in many inflammatory markers, including interleukin 6 IL6. Air pollution exposure has also been suggested to induce an imbalance in the autonomic nervous system ANS , such as a decrease in heart rate variability HRV.
In this study we aimed to investigate the modifying effect of polymorphisms in a major proinflammatory marker gene, interleukin 6 IL6 , on the relationship between long-term exposure to traffic-related PM 10 TPM 10 and HRV. Included were persons with valid genotype data, who underwent ambulatory hr electrocardiogram monitoring, and reported on medical history and lifestyle. Main effects of annual average TPM 10 and IL6 gene variants rs; rs; rs; rs on HRV indices and their interaction with average annual exposure to TPM 10 were tested, applying a multivariable mixed linear model.
Our results are consistent with the hypothesis that traffic-related air pollution decreases heart rate variability through inflammatory mechanisms. This is an open-access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. No form of payment was given to any of the authors to produce the manuscript. The study received funding through peer-reviewed grants and donations from non-profit organizations as listed above.
The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist. Exposure to air pollution as well as decreased heart rate variability HRV as measured by specific indices SDNN, TP, LF, HF have been associated with increased cardiovascular morbidity and mortality in longitudinal studies, both in patients with myocardial infarction and in healthy persons [1] β [3].
Heart rate variability HRV refers to the beat-to-beat variation in heart rate and is a non-invasive measure of the autonomic regulation of cardiac rhythm [4] , [5]. A reduction in different HRV indices can reflect both an increase in sympathetic or a decrease in parasympathetic tone [2].
