Young adults who take cocaine significantly increase their risk of suffering a stroke within 24 hours of use, new research indicates.

The risk refers to ischaemic strokes, which are caused by a sudden blockage in the blood vessels supplying blood to the brain. Up to 90% of strokes are ischaemic.

US researchers set out to investigate what factors contribute to stroke risk in young adults. They compared over 1,100 people, aged 15 to 49, who had suffered a stroke between 1991 and 2008, with over 1,100 people of similar ages who had never suffered a stroke.

At least one in four of the people in both groups admitted to using cocaine - men were twice as likely than women to use the drug.

The researchers found that having a history of cocaine use was not linked with ischaemic stroke. However use of the drug in the 24 hours before a stroke was strongly linked with an increased risk.

In fact, users were up to seven times more likely to suffer a stroke within 24 hours of taking the drug.

This risk appeared to affect all ethnicities.

"Cocaine use is one of the risk factors we investigated and we were surprised at how strong an association there is between cocaine and stroke risk in young adults. We found the stroke risk associated with acute cocaine use is much higher than some other stroke risk factors, such as diabetes, high blood pressure and smoking," the researchers said.

They added that with only a few exceptions, ‘every young stroke patient should be screened for drug abuse at the time of hospital admission'.

Details of these findings were presented at the American Stroke Association's International Stroke Conference 2014 in San Diego.