"The findings validate breathing polluted air for an extended period of time puts you at substantial risk for heart disease, and the publication in JAMA certainly adds to the body of evidence," said Dr. Sanjay Rajagopalan, MD FACC, Associate Professor of Medicine and Radiology, Director Clinical Cardiovascular MRI and CT Program at the Zena and Michael A. Wiener Cardiovascular Institute at the Mount Sinai School of Medicine and lead author of this study. "It has tremendous ramifications for public health and health policy for those of us living in cities."
Real-world study validates findings
Other published studies on this topic use data collected from time-series analysis of human participants or in vitro studies where cells were exposed to non-physiologic and sometimes high concentrations of particulate matter. However, air pollution particles most strongly linked with cardiovascular disease are 2.5µm (PM2.5) and smaller and primarily derived from stationary and traffic-related combustion sources.
To better reflect human, real-world exposure, Mount Sinai School of Medicine Researchers used mice and airborne particulate matter with diminishing size down to .5µm to demonstrate an incremental capacity to penetrate to the most distal airway units and potentially the systemic circulation.
The Study
Mount Sinai School of Medicine Researches tested the hypothesis that subchronic exposure to environmentally relevant particulate matter, even at low concentrations, causes atherosclerosis and alters vasomotor tone in a susceptible disease model.
Between July 21, 2004 and January 12, 2005, 28 mice were fed normal chow or high-fat chow and exposed to concentrated ambient particles of less than 2.5µm or filtered air for 6 hours per day, 5 days per week for a total of 6 months. To test the hypothesis, researchers looked for composite atherosclerotic plaque in the thoracic and abdominal aorta and vasomotor tone changes in the mice.
They concluded that in a mouse model, long-term exposure to low concentration of PM(2.5) altered vasomotor tone, induced vascular inflammation, and potentiated atherosclerosis.
You can read the full study in the December 21, 2005 issue of JAMA.
Cardiovascular Research At Mount Sinai
The Zena and Michael A. Wiener Cardiovascular Institute and the Marie-Josée and Henry R. Kravis Center for Cardiovascular Health at The Mount Sinai Medical Center are preeminent resources for the study and treatment of heart and blood vessel diseases. Committed to finding new and improved methods of diagnosis, treatment and prevention, they comprise a multidisciplinary effort that brings together the extraordinary expertise of Mount Sinai School of Medicine and The Mount Sinai Hospital in cardiology, cardiovascular surgery, medical education, research and community service, with state-of-the-art facilities for patient care, advanced laboratories for scientific research and leading programs for postgraduate education of clinician-scientists.
Mount Sinai School of Medicine
Located in Manhattan, Mount Sinai School of Medicine is internationally recognized for ground-breaking clinical and basic-science research, and innovative approaches to medical education. One indication of Mount Sinai's leadership in scientific investigation is its receipt during FY00 of $168 million in public and private research funding, including over $112 million in NIH grants, placing it 22nd among the nation's 125 medical schools. Mount Sinai School of Medicine is also known for unique educational programs that not only prepare students to be highly skilled care givers, but help them to reach their maximum potential as caring, well-rounded people. Long dedicated to serving its community, the School extends its boundaries to improve health care delivery, educational opportunities and quality of life for residents of East Harlem and surrounding communities.
Journal
JAMA