BMJ 2014;348:g3702 doi: 10.1136/bmj.g3702 (Published 5 June 2014)
Page 1 of 1
Research News
RESEARCH NEWS Researchers find no clear link between air pollution and heart attack or strokes Jacqui Wise London
A new analysis has found no clear evidence that short term increases in air pollution are linked to a rise in heart attacks or strokes.1 However, the research indicates levels of particulate matter are linked to an increased risk of arrhythmia, atrial fibrillation, and pulmonary embolism.
The study, published in the journal Heart, used the Myocardial Ischaemia National Audit Project (MINAP) database to identify all acute admissions for myocardial infarction and stroke in England and Wales together with hospital episode statistics on emergency admissions and figures from the Office for National Statistics on recorded deaths. The researchers from the London School of Hygiene and Tropical Medicine analysed 400 000 myocardial infarctions, more than two million cardiovascular disease emergency hospital admissions, and more than 600 000 cardiovascular deaths. These were linked to daily mean concentrations of carbon monoxide, nitrogen dioxide, particulate matter (PM10 and PM2.5), sulphur dioxide, and ozone levels over a period of five days at the nearest air pollution monitoring site to their place of residence. Information on ambient daily temperatures was also factored in.
No clear link with any air pollutant was found for cardiovascular deaths. Only fine particulate levels (PM2.5) were linked to an increased risk of arrhythmia, atrial fibrillation, and pulmonary embolism. With hospital admissions, only nitrogen dioxide was associated with a raised risk of cardiovascular disease (by 1.7% (95% confidence interval 0.9% to 2.6%)), arrhythmias (2.9% (0.6% to 5.2%)), atrial fibrillation (2.8% (0.3% to 5.4%)), and
For personal use only: See rights and reprints http://www.bmj.com/permissions
heart failure (4.4% (2.0% to 6.8%)). In general, there was little evidence of a pollution effect on myocardial infarction risk. Only nitrogen dioxide was associated with an increased risk of myocardial infarction and this was specific to non-ST segment elevation myocardial infarction (non-STEMI) (3.6% (0.4% to 6.9%)). The study found that, in general, effects of nitrogen dioxide on hospital admissions and particulate matter on mortality were higher in those over 70 years and in women.
In an accompanying editorial Anoop Shah and David Newby, cardiologists from the University of Edinburgh, point out that the median PM2.5 concentration in the study was 10 µg/m3 within a relatively narrow range (7 to 15 µg/m3).2 Levels more than 10 to 20 times higher are found in many large cities across the world, they said. They concluded: “The current lack of consistent associations with contemporary UK data may suggest that as the fog begins to clear, the adverse health effects of air pollution are starting to have less of an impact and are more difficult to delineate.” 1
2
Milojevic A, Wilkinson P, Armstrong B, Bhaskaran K, Smeeth L, Hajat S. Short-term effects of air pollution on a range of cardiovascular events in England and Wales: case-crossover analysis of the MINAP database, hospital admissions and mortality. Heart Jun 2014. doi:10.1136/heartjnl-2013-304963. Shah ASV, Newby DE. Less clarity as the fog begins to lift. Heart Jun 2014. doi:10.1136/ heartjnl-2014-305877.
Cite this as: BMJ 2014;348:g3702 © BMJ Publishing Group Ltd 2014
Subscribe: http://www.bmj.com/subscribe
Page 1 of 1
Research News
RESEARCH NEWS Researchers find no clear link between air pollution and heart attack or strokes Jacqui Wise London
A new analysis has found no clear evidence that short term increases in air pollution are linked to a rise in heart attacks or strokes.1 However, the research indicates levels of particulate matter are linked to an increased risk of arrhythmia, atrial fibrillation, and pulmonary embolism.
The study, published in the journal Heart, used the Myocardial Ischaemia National Audit Project (MINAP) database to identify all acute admissions for myocardial infarction and stroke in England and Wales together with hospital episode statistics on emergency admissions and figures from the Office for National Statistics on recorded deaths. The researchers from the London School of Hygiene and Tropical Medicine analysed 400 000 myocardial infarctions, more than two million cardiovascular disease emergency hospital admissions, and more than 600 000 cardiovascular deaths. These were linked to daily mean concentrations of carbon monoxide, nitrogen dioxide, particulate matter (PM10 and PM2.5), sulphur dioxide, and ozone levels over a period of five days at the nearest air pollution monitoring site to their place of residence. Information on ambient daily temperatures was also factored in.
No clear link with any air pollutant was found for cardiovascular deaths. Only fine particulate levels (PM2.5) were linked to an increased risk of arrhythmia, atrial fibrillation, and pulmonary embolism. With hospital admissions, only nitrogen dioxide was associated with a raised risk of cardiovascular disease (by 1.7% (95% confidence interval 0.9% to 2.6%)), arrhythmias (2.9% (0.6% to 5.2%)), atrial fibrillation (2.8% (0.3% to 5.4%)), and
For personal use only: See rights and reprints http://www.bmj.com/permissions
heart failure (4.4% (2.0% to 6.8%)). In general, there was little evidence of a pollution effect on myocardial infarction risk. Only nitrogen dioxide was associated with an increased risk of myocardial infarction and this was specific to non-ST segment elevation myocardial infarction (non-STEMI) (3.6% (0.4% to 6.9%)). The study found that, in general, effects of nitrogen dioxide on hospital admissions and particulate matter on mortality were higher in those over 70 years and in women.
In an accompanying editorial Anoop Shah and David Newby, cardiologists from the University of Edinburgh, point out that the median PM2.5 concentration in the study was 10 µg/m3 within a relatively narrow range (7 to 15 µg/m3).2 Levels more than 10 to 20 times higher are found in many large cities across the world, they said. They concluded: “The current lack of consistent associations with contemporary UK data may suggest that as the fog begins to clear, the adverse health effects of air pollution are starting to have less of an impact and are more difficult to delineate.” 1
2
Milojevic A, Wilkinson P, Armstrong B, Bhaskaran K, Smeeth L, Hajat S. Short-term effects of air pollution on a range of cardiovascular events in England and Wales: case-crossover analysis of the MINAP database, hospital admissions and mortality. Heart Jun 2014. doi:10.1136/heartjnl-2013-304963. Shah ASV, Newby DE. Less clarity as the fog begins to lift. Heart Jun 2014. doi:10.1136/ heartjnl-2014-305877.
Cite this as: BMJ 2014;348:g3702 © BMJ Publishing Group Ltd 2014
Subscribe: http://www.bmj.com/subscribe
