TIA doubles MI risk
MedWire News: Patients with transient ischemic attack (TIA) are at increased risk for myocardial infarction (MI), which in turn further raises their mortality risk, research shows.
"Physicians and other healthcare providers should be mindful of the increased risk for heart attack after TIA, just as they are about the increased occurrence of stroke," said lead researcher Robert Brown (Mayo Clinic, Rochester, Minnesota, USA).
"In the same way that we evaluate the patient to determine the cause of TIA and implement strategies to reduce the occurrence of stroke after a TIA, we should step back and consider whether a stress test or some other screening study for coronary artery disease should also be performed after a TIA, in an attempt to lessen the occurrence of heart attack."
The finding is based on an analysis of 388 participants in the Rochester Epidemiology Project who suffered a TIA between 1985 and 1994, and had not previously suffered a MI.
The patients were an average of 71 years old at the time of their TIAs, and 41% were male. During follow-up to the end of 2006 (median=10.2 years), 44 patients suffered MI, show the results published in the journal Stroke.
This equated to an annual MI incidence of 0.95%, which was 2.09-fold greater than the age-, gender-, and period-specific rate in the general population.
The highest MI risk was observed in patients younger than 60 years, at 15.1 times that of the same age group in the general population. For patients older than 60 years, the risk elevation was 1.93-fold, but still statistically significant.
The risk for MI after TIA remained constant over time, the researchers note. The underlying cause of TIA did not predict MI; however, TIA etiology could not be determined in over half of the patients.
Finally, MI was an independent predictor of death in TIA patients, increasing the risk 3.11-fold.
"Coronary-artery disease is an even greater cause of death after TIA than stroke is, surprising as that may be," said Brown.
"We should use the TIA event not only to provide a warning sign that patients are at heightened risk of stroke, but are also at increased risk of heart attack, an event that will increase their risk of death after the TIA."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Eleanor McDermid