Study links winter air pollution in Ireland with increased stroke hospitalisation

11 Aug 2020

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RCSI researchers are calling for stricter measures against solid fuel burning after finding a link between them and higher rate of strokes, particularly in Dublin.

A study published today (11 August) to the Cerebrovascular Diseases journal has found that air pollution in winter is associated with an increased rate of hospitalisations related to strokes in Dublin. During this time, particularly in the captial, higher levels of fine particles, coarse particles, sulphur dioxide and nitrogen dioxide are found in the air.

Solid fuel burning – such as from diesel engines, coal and peat – are the sources of these particles, according to the research authors from the Royal College of Surgeons in Ireland (RCSI), the HSE and Trinity College Dublin. After accounting for variables such as temperature, humidity, day of the week and time, the researchers found that there was a statistically significant rise in the number of hospitalisations for strokes in Dublin between zero and two days after a rise in air pollution.

When it came to higher levels of nitrogen dioxide and sulphur dioxide, they found both had an associated 3.5pc higher risk of stroke. This was followed by a 3.2pc higher risk for increased levels of coarse particles and a 2.4pc higher risk for finer particles.

Call for ban on solid fuel burning

“Every year, more than 10,000 people in Ireland have a stroke,” said Dr Colm Byrne, the study’s lead author. “Our research adds evidence that there needs to be a national ban on solid fuel burning to help in our efforts to reduce this number.”

While Dublin has seen the greatest association with air pollution and increased chances of stroke, no significant association was found in the smaller urban area of Cork. However, meta-analysis showed a significant association between hospitalisations for strokes and higher levels nitrogen dioxide and fine particles in the air.

David Williams, a professor of stroke medicine at RCSI, added: “Because Ireland has relatively low air pollution when compared internationally, this highlights the need to introduce additional policy changes to reduce air pollution in all countries.”

Earlier this year, researchers from Science Foundation Ireland’s MaREI energy and marine research centre based at University College Cork showed levels of air pollution in Ireland from solid-fuel burning have not changed since the beginning of the Covid-19 pandemic and are generally in line with the monthly average.

However, there has been a significant decrease of up to 50pc in concentrations of the greenhouse gas nitrogen oxide.

Colm Gorey was a senior journalist with Silicon Republic