This is in contrast to those who spend more time being physically active.
A stroke, also known as a cerebrovascular accident or CVA, is a medical emergency that occurs when part of the brain loses its blood supply and the part of the body that the blood-deprived brain cells control stops working.
In the study published in the journal Stroke by the American Heart Association, adults who reported sitting eight or more hours were seven times more at risk of stroke than people who spent fewer than four hours being sedentary.
The researchers analysed the health information of 143,000 adults from the Canadian Community Health Survey.
They followed the participants, who were 40 and older with no prior history of stroke, for an average of 9.4 years.
Raed Joundi, a clinical scholar at McMaster University in Ontario, Canada, who is the lead author, said: “Sedentary time is thought to impair glucose, lipid metabolism, and blood flow, and increase inflammation in the body.”
“These changes, over time, may have adverse effects on the blood vessels and increase the risk of heart attack and stroke.”
Of the 2,965 strokes participants had during the study period, the researchers found that 90 percent were ischemic.
Joundi said ischemia, which is common, happens when an artery that supplies blood to the brain is blocked.
If the stroke isn’t treated quickly, the author added, the brain cells in that area may start to die from lack of oxygen.