Home air filters may improve elders' heart health
By Anne Harding
NEW YORK (Reuters Health) - When high-efficiency particle air (HEPA) filters were used for just 48 hours to clean the air in the apartments of 21 older couples, their blood vessel function improved by about 8 percent, Danish researchers have shown.
While the couples were all non-smokers, the improvement seen in the study was "in the same ballpark" as would be seen after a person quits smoking, Dr. Steffen Loft of the Institute of Public Health in Copenhagen, the study's lead author, told Reuters Health.
There is a wealth of data on how breathing minute particles carried in the air, known as particulate matter, can worsen heart and lung disease and even increase mortality rates, Loft and his team note in the American Journal of Respiratory and Critical Care Medicine.
To better understand how particulate matter in indoor air affects health, the researchers used a battery of tests to assess microvascular function and inflammation in 21 couples 60 to 75 years old after breathing nonfiltered air, and then after breathing filtered air for 48 hours.
Microvascular function looks at how well the tiny blood vessels linking the veins and arteries are able to relax and dilate in response to blood and oxygen demands, Loft explained. Impairment of microvascular function is a sign of coronary heart disease, and can also promote atherosclerosis, he added.
On average, microvascular function improved by 8.1 percent for the study participants after they had spent two days breathing filtered air. "It may ... be speculated that further improvement may occur after prolonged intervention by 6 months to 1 year, and that this could result in further reduction in cardiovascular risk in this healthy, elderly age group," the research team concludes.
Indoor air pollution typically comes from heating sources, candles, cooking, nearby traffic and even a neighbor's cigarette smoke, for some apartment dwellers, Loft said. The key finding of the current study, according to the researcher, is that "the level of particles in a regular, normal home actually affects the vascular function in elderly people."
"Air pollution, both indoor and out, is certainly affecting people's hearts," he added.
Loft and his colleagues now plan to investigate how particulate matter from wood stoves used to heat homes in Scandinavia and parts of the United States can affect health.
SOURCE: American Journal of Respiratory and Critical Care Medicine, February 15, 2008.