(Reuters) – living in a very populous city or near a freeway with much traffic, where the air quality is bad, could generate greater chance of an accident, stroke (LCA) or memory loss, according to two us studies indicate.
Both reports were published in Archives of Internal Medicine.
One study reveals increased risk of LCA among residents of the Boston area after some days when the air quality was “moderate”, rather than “good”, especially when the traffic-related pollution was high.
Other research, which noted thousands of women, documented a decline in long-term thinking and memory skills in those living in more polluted areas of United States faster.
None of the findings could prove that pollutants were responsible for the LCA and memory problems, but previous studies supported the results of negative effects of pollution on the heart and blood vessels.
“One of the important points is that at levels which are generally considered safe by the EPA (environmental protection agency) of United States we are witnessing important effects on health,” said Gregory Wellenius, of Brown University in Providence, Rhode Island, who directed the study on LCA.
Wellenius team reviewed the medical records of some 1,700 patients who entered the Beth Israel Deaconess Medical Center in Boston with an LCA between 1999 and 2008.
From data from a local station for control of pollution, the team found that the risk of having an LCA was a 34% higher within 24 hours to “moderate” readings of pollution according to the EPA, compared to the so-called “good” days.
This increased risk was higher within 12 to 14 hours of exposure to pollution, and was linked to a transit-related pollutant, nitrogen dioxide.
Wellenius said that blood vessels are dilated and contracted as a response to the external environment, in an attempt to maintain constant blood pressure. But the air pollution would affect the body’s ability to regulate the pressure, which could generate an LCA in people already at risk, he added.
This same effect could explain why, after a longer period of time, be exposed to air pollution may be associated with a decline in thinking and memory.
“The blood flow to the brain is incredibly important for cognitive function.” “Would have (…) effects on the blood flow to the brain that still unknown to us may affect cognitive function,” said the expert.
In another study, experts led by Jennifer Weuve of the University Medical Center of the Rush in Chicago analyzed a series of cognitive tests carried out some 20,000 women, most aged between 70 and 80 years, and also felt the pollution of the air around their homes through the system of monitoring of the EPA
Researchers found that a greater environmental pollution was linked to rates more accelerated cognitive impairment.
For two different sizes of particles of pollution, the difference in thinking and memory capacity among women with some of the major and minor exhibitions were similar to one or two years of age-related deterioration, reported the team.
This is probably a mental change that notary not a person individually, Weuve told Reuters Health. But on a population scale, cleaner air would mean fewer people diagnosed with dementia of United States.
Jiu-Chiuan Chen, expert in environmental health in the school of medicine Keck of the University of Southern California in Los Angeles, who did not participate in any of the studies added that results on cognitive function should not concern to women but do generate more studies on the effects of environmental pollution in thinking and memory.
(Report from New York of Genevra Pittman); (Edited by Ana Laura Mitidieri in Spanish)
