Noise pollution is harmful not just to your ears, but to you health as it can increase chance for stroke. But more green spaces means lesser risk of stroke.
A study by a group of organisations have found that people living in large cities with high levels of environmental noise have a higher chance of ischaemic stroke. In fact, the risk is up by 30% compared to those living in other places.
The study was done by researchers from the Hospital del Mar Medical Research Institute (IMIM) and doctors from Hospital del Mar, together with researchers from the Barcelona Institute for Global Health (ISGlobal), CIBER in Epidemiology and Public Health (CIBERESP), and Brown University, in the United States.
The study also found that the risk of stroke came down by upto 25% in those living closer to green areas. The study has been published in the journal Environmental Research. The researchers looked at the influence of noise levels, air pollution (particularly suspended particles smaller than 2.5 microns; PM2.5), and exposure to green areas on nearly 3,000 ischaemic stroke patients treated at Hospital del Mar between 2005 and 2014.
“Previous studies have demonstrated that living in places with high levels of air pollution or noise, or with fewer green areas, exposes the population to a higher risk of suffering an ischaemic stroke. This work broadens our knowledge in this field, showing that the place where we live affects not only the risk of suffering a stroke, but also its severity if it occurs,” explains Dr Gregory A. Wellenius, from the Epidemiology Department at Brown University and final author of the study.
The researchers have analysed the effects of stroke on neurological deficits, such as speech impairment and mobility. The severity of a stroke depends on various factors, including the extent of the brain injury, the specific area of brain affected, the subtype of stroke, the existence of associated risk factors (diabetes, atrial
fibrillation, atherosclerotic load), and so on. The environmental aspects like green spaces and urban noise levels affect the severity of a stroke.
Ischaemic stroke is due to the obstruction of a blood vessel in the brain and accounts for 80-85% of all cases. This lack of blood flow in the affected area of the brain can lead to permanent damage. The risk of having a stroke is closely related to factors including age, smoking, high blood pressure, diabetes, obesity, a sedentary lifestyle and, as recently demonstrated, other factors like air pollution.