A patient who suffers a minor stroke or transient ischemic attack (TIA) has a significant risk of experiencing a major stroke within 1 week, according to a study published in the December issue of Lancet Neurology. However, the researchers note that minor stroke patients who are treated in stroke units run the lowest risk of a major stroke afterwards.
Matthew Giles, MD, and Peter Rothwell from the Stroke Prevention Research Unit at the University of Oxford, United Kingdom, examined all studies of major stroke risk within one week after TIA to estimate the overall stroke risk.
The researchers examined 18 cohorts involving 10,112 patients, and concluded the risk of major stroke within seven days of a TIA is 5.2 percent, which is substantial. One in 20 patients who have a TIA will have a major stroke within one week.
According to researchers, the variations in calculated risks were mainly due to study method, setting and treatment. They found that the lowest risk of major stroke within seven days of a TIA were emergency treatment studies in specialist stroke units—the risks were estimated to be 0.9 percent. The highest risk of 11 percent was among population-based studies without urgent treatment.
The authors concluded that risk of stroke reported among patients treated urgently in specialist units was substantially lower than the risk reported among other patients treated in alternative settings. The authors also concluded that the results support the argument that a TIA is an emergency and that urgent treatment in specialist units may reduce the risk of subsequent stroke.