Overdiagnosis neglects the real underlying illness. Underdiagnosis leaves a patient at risk of a full-fledged stroke. Both expose patients to erroneous therapies with potential side effects.
And yet, TIAs are difficult to assess because, by definition, the neurological dysfunction that results is so brief. By the time the patient arrives at a doctor's office or an emergency room, the symptoms are often gone.
Now, researchers at Rush University Medical Center have identified three bedside clinical features that can help more accurately distinguish TIAs from disorders that might mimic their symptoms.
The study has just been published online and will appear in the December issue of Cerebrovascular Diseases .
Two neurologists at Rush University Medical Center, Dr. Shyam Prabhakaran, lead author of the study and head of the stroke service, and Dr. Vivien Lee examined the records of 100 emergency room patients who had an initial diagnosis of TIA and were admitted for further evaluation. Only 40, or 40 percent, of these cases turned out to be true TIAs.
The researchers were able to identify three clinical features that, together, correctly classified 79 percent of the cases.
"Speed of onset, we found, was the strongest indicator of a TIA. I typically ask my patients if their symptoms came on like lightning, within seconds," Prabhakaran said. "With other neurological problems that can mimic a TIA – migraines or seizures, for example – symptoms take more than a minute to manifest themselves."
The researchers found that a TIA was unlikely if a patient reported nonspecific symptoms, such as lightheadedness, tightness in the chest or stomach upset, along with the neurological dysfunction.