Study links risk of cardiac arrest with air pollution from wildfires
18 Jul 2015
Air pollution from wildfires might up the risk of cardiac arrest and other sudden acute heart problems, according to a study.
"While breathing wildfire smoke was linked to respiratory problems such as asthma - evidence of an association between wildfire smoke exposure and heart problems has been inconsistent," says lead author Anjali Haikerwal, department of epidemiology and preventive medicine, at Australia's Monash University.
The association between exposure to tiny particulate pollutants from wildfire smoke and the risk of heart-related incidents in the state of Victoria between December 2006 and January 2007 was investigated by the researchers.
According to the study published in the Journal of American Heart Association, during these two months, smoke reached cities far from the blazes and on most days the levels of fine particulate air pollutant exceeded recommended air quality limits.
For a rise from the 25th to 75th percentile in particulate concentration over two days, after adjusting for temperature and humidity, there was a 6.98 per cent increase in out-of-hospital cardiac arrests, as also a stronger association between pollution and cardiac arrests in men and people 65 and older.
An increase of 2.07 per cent was seen in emergency department visits for acute cardiac events and 1.86 per cent increase in hospitalisations for acute cardiac events, with a stronger association in women and people 65 and older was also seen.
Haikerwal explains, ''Finer particulate matter is present in extremely high concentration in smoke,'' adding that it's so harmful ''due to the fact that they are little and conveniently inhaled.''
The particles from the study that Haikerwal referred to are smaller than three thousandths of a millimeter in diameter, which is smaller than a spec of dust and not visible to the human eye. People would, therefore have no way of knowing they were inhaling potentially harmful particles.
During the time period under study, there were 457 out-of-hospital cardiac arrests, as also 2,106 ER visits and 3,274 hospital admissions for coronary artery disease. These rates were significantly higher than those before the wildfires in Victoria.
However, it needed to be kept in mind that this was an observational study.
Haikerwal wanted to reiterate that fine particles that are potentially harmful to one's cardiac health were more abundant in wildfire smoke than other forms of smoke and pollution.
