Largest Study So Far Links Stroke to Air Quality and Climate Change
Research presented at the International Stroke Conference in Los Angeles has linked poor air quality and climate change to an increase in the number of strokes in the US and China. Scientists chose the two countries as they were ‘the world’s two largest emitters of greenhouse gases and responsible for about one-third of global warming to date.’
The research is the first of its kind, investigating the interaction between stroke prevalence, air quality and the potential effect of temperature. Data on air quality was collected from Environmental Protection Agency records of 1,118 counties and 49 states in the US, as well as 120 cities and 32 provinces in China between 2010 and 2013.
Measurements were based on particulate levels which were then cross referenced with government public health data on stroke rates. After adjusting for factors that included poverty rate, race and age, they found that for every 10 micrograms per cubic meter increase of particulate matter, incidences of stroke rose 1.19 percent.
Stroke risk was also found to be higher at higher temperatures as lead researcher Longjian Liu explained; “Seasonal variations in air quality can be partly attributable to the climate changes,” he said. “In the summer, there are lots of rainy and windy days, which can help disperse air pollution. High temperatures create a critical thermal stress that may lead to an increased risk for stroke and other heat and air quality related illnesses and deaths.” The World Heart Federation estimate that 15 million people suffer a stroke every year while the condition is the third largest cause of death in the UK.