[ARCHIVED] Adverse Cardiovascular Health Effects of Exposure to Short-Term Air Pollution

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Based on appraisals of recent systematic reviews and patient information, this report provides an overview of: 1) evidence available to generate health protection measures; 2) health protection advice currently recommended to persons with/at risk of cardio-vascular diseases through public health, medical, patient information, environmental, and meteorological websites; and 3) a general framework to develop health protection measures.

The commonly monitored air pollutants: particulate matter (PM), sulphur dioxide, nitrogen oxides, carbon monoxide, and ozone are all known to be harmful to human health. PM appears to be the most important and best documented cause of cardiovascular adverse effects. There is no firm understanding of specific populations or individuals most vulnerable to cardiovascular effects of air pollution, but it is recognized that certain groups are more at risk: the elderly, persons with pre-existing respiratory and cardiovascular diseases, and persons of low socio-economic status. There is an increasing understanding of the pathophysiological mechanisms underlying the effects of air pollution on the cardiovascular system. It is suspected that exposure is influenced by diurnal concentrations of air pollutants, building characteristics, location, and individual rates of inhalation. The focus of current health protection measures is mainly on decreasing the exposure
to short-term air pollution through reduction, rescheduling, or relocation of outdoor activities.

Further research is needed to fully understand: who is most at-risk, how does air pollution results in increased cardiovascular disease, precisely how do outdoor air pollutant levels vary, what specifically increases individuals’ exposure, what people should do to counteract short-term air pollution, and if health protection messages lead to safer behaviours among vulnerable populations and whether they decrease the adverse health effects of air pollution.

Recommendations: Public health practitioners should inform the population of the cardiovascular risks of air pollution. Health protection measures should target the entire population, with a special focus on the elderly, persons with pre-existing cardiovascular and respiratory diseases, and those with low socio economic status, to decrease their exposure primarily by decreasing proximity to air pollution sources and by decreasing strenuous activity during days or periods of high pollution. Health protection measures remain an insufficient mitigation strategy given their uncertain efficacy. Aiming for long-term avoidance of air pollution should remain the primary goal.