Minor strokes tied to major attacks within a week

The chances of having a major stroke increase significantly in those who suffer a minor stroke, called a TIA, within a week before the major event, but the likelihood is lessened if the patient receives emergency treatment for the so-called small stroke, according to new British research.

A review of previous studies involving more than 10,000 patients found that approximately one in every 20 patients who suffered a TIA – technically known as a transient ischemic attack – had a major stroke in seven days or less after the minor event. The same findings added, however, that treatment for the TIA in a special stroke unit at a hospital emergency area often effectively blunted the chances of a major attack.

For example, the team’s interpretation of previous studies concluded that in general there is a 5.2% risk of a major stroke within a week of suffering a TIA, but for patients treated in emergency stroke care for a TIA, the risk ranged from no risk to a high of 9%. The overall highest risk was for those who received no emergency care for their TIA, and that likelihood for a major attack rose to 11%.

In the United States, where stroke is the third most common cause of death, about 700,000 people suffer a stroke each year. According to the American Heart Association, more than 150,000 Americans die from stroke each year, about 61% of them women.

“The risk of stroke reported amongst patients treated urgently in specialist units was substantially lower than risks reported among other patients treated in alternative settings. These results support the argument that a TIA is a medical emergency and that urgent treatment in specialist units may reduce the risk of subsequent stroke,” the study authors wrote in their report published online in the journal The Lancet Neurology. The research was conducted by a team from Oxford University’s Stroke Prevention Research Unit.

Earlier studies – part of those reviewed by the Oxford team – variously placed the chances of a major stroke after a TIA between no statistical chance and as high as 12.8%, but the Oxford team said the inconsistencies were mostly likely the result of varying study methods in the range of studies.

“Our study almost fully explains why the results of previous studies have been conflicting and illustrates the importance of methods used by a medical study when interpreting its results,” the Oxford team wrote.

These researchers hope their conclusions will result in more comprehensive emergency care and planning for TIA victims as well as improved public education about the true risk associated with these small strokes.