08/02/2010 - Press release
It has been proven scientifically for the first time that atmospheric contamination accelerates the atherosclerosis process by more than double its average evolution and, therefore, increases the chances of suffering a heart attack or cerebrovascular malady. This was demonstrated by researchers at the Environmental Epidemiology Research Centre (CREAL) in Barcelona, jointly with Swiss researchers and from the University of Southern California in the study ‘Atmospheric Contamination and the Evolution of Arteriosclerosis in Adults’, which was just published in the magazine PLoS ONE.
The study concluded that the annual development of the artery walls of those living within 100 metres of a motorway or busy with high traffic levels suffer from an acceleration in the growth of the plaques of their arteries of 5.5 micrometres per year, or over double the average annual growth.
According to Xavier Basagaña, a CREAL researcher and participant in this study, ‘these results are extremely significant, considering the relevance of atherosclerosis in Western countries’. Cardiovascular diseases are the leading cause of death in developed countries, higher even than for cancer. For example, every week 770 Spaniards die from some type of ischaemic heart disease (heart attack, angina pectoris and sudden death) and in Catalonia specifically, some 120 die each week of heart diseases.
Until present, scientific studies have proven that air pollution can give rise to heart attacks, among other health problems. However, this study proves for the first time that this contamination can cause such complex changes in the arteries as atherosclerosis, a malady in which fatty materials are deposited along the arteries’ walls that can result in heart attack or cerebrovascular accident. This process had been previously observed in animals.
People with high cholesterol affected more
The effect of contamination on atherosclerosis is seen more in patients who receive treatment to reduce cholesterol levels and those with low socioeconomic levels. Possible causes are firstly that they already have higher risk and, secondly, due to the combination of other exposures to contamination, poor diets and the stress to which they are exposed.
Moreover, some participants received some type of treatment with vitamins B, E or estrogens during the study. People involved in these treatments are ‘more vulnerable to the effects of pollution’. Even so, the complex interactions that can exist between the effect of medicines, exposure to contamination and other individual characteristics ‘must be explored in much greater detail in future studies’, confirmed Xavier Basagaña.
Barcelona, worse than Los Angeles
Some 1500 people from Los Angeles, California participated in this study and the progression of atherosclerosis was measured every six months over a three-year period. Remember that Barcelona has contamination levels much higher than the recommendation of the World Health Organisation (WHO) and also has contamination levels higher than most districts of Los Angeles. Furthermore, according to Basagaña, “There are many more diesel-fuelled automobiles in Barcelona than in Los Angeles, where almost all private vehicles run on regular petrol and contamination by diesel vehicles can be much more damaging to the health’.
In fact, the WHO recommends that suspended particle levels (basically produced by traffic) are no higher than 40 micro-grams per cubic metre and Barcelona has between 45 and 50 micro-grams per cubic metre, whereas Los Angeles has 25-30 micro-grams per cubic metre.
At present, CREAL and the Municipal Institute of Medical Research (IMIM-Hospital del Mar) are performing a similar study in Girona entitled REGICOR-AIR. They calculate that the first results will be available within one or two years and will give an idea of the effects of contamination in Spain even though ‘Girona has lower contamination levels than in cities like Barcelona and Madrid’ , states Basagaña.