To the Editor:
The term transient ischemic attack (TIA) is problematic. New evidence of an even greater than previously appreciated risk of impending stroke is accumulating. The recent article by Lovett et al provides resounding data in support of this.1 An article published several months previously is particularly pertinent in this regard. Albers and others were more forthright in their revocation of the long-overdue recision of the term TIA.2 Albers et al recommended that we should keep the term TIA but that we must understand it should mean something different!
However, TIA and its connotations in clinical practice demand a catchy replacement acronym. The term must somehow satisfy medical and nonmedical people and yet be accurate, brief, and remembered. The term TIA was also regarded as a relatively benign syndrome with nonemergent status. This needs to be urgently corrected.
The call for a more appropriate and sinister term is particularly relevant.2 We need to keep it short and self explanatory, and yet it must be accurate from a pathophysiological point of view. An abandonment of the term TIA in its present form may be unnecessary.
In my view, a term that can steal the popularity and yet metamorphose into a more appropriate acronym would be TIB: threatening infarct of the brain. TIB encompasses both transience and evolution into something more disastrous; it is biologic end point–based rather than a temporal parameter and incites or should kindle a sense of urgency among clinicians and laity alike.
I agree with Dr Hoffmann that we need to engender in our medical colleagues a far greater sense of urgency in the management of patients with TIA and minor stroke. We also need to educate the public about the importance of seeking medical attention as an emergency. However, we first need to carefully justify the need for emergency status for TIA and minor stroke.
First, we need to be certain about the high early risk of recurrent stroke. Our recent article in Stroke1 was based on a re-analysis of data from a study that was performed in the 1980s. It is therefore possible that the early risk of stroke after a TIA is now lower because of improvements in primary and secondary prevention of stroke. However, preliminary analysis of data from our current population-based study of TIA and stroke (Oxford Vascular Study) has produced estimates of the risk of stroke after a TIA or minor stroke of 10.2% (95% CI=5.6 to 14.8) at 7 days and 13.8% (95% CI=8.6 to 19.0) at 1 month. These risks are consistent with our recent publication1 and certainly justify emergency status.
Second, emergency status also requires that we can prevent some of these early recurrent strokes, or at least that there is a reasonable potential that future research will identify effective preventive treatments. It is likely that antiplatelet therapy will reduce the early risk and trials of combination therapy are ongoing. Further trials are required of blood pressure lowering in the acute phase and there is a potential for trials of neuroprotective agents to take advantage of the opportunity to “pretreat” patients prior to any recurrent stroke. Of particular importance is the recent observation that the subgroup of patients with carotid stenosis account for the highest proportion of early recurrent strokes at 7 days and 1 month in population-based studies.2 Endarterectomy is highly effective in this subgroup,3 and the absolute benefit derived from surgery has recently been shown to fall rapidly with delay between presenting event and surgery during the first few weeks after the event.4 Although endarterectomy has a high operative risk in the hyperacute phase in patients with unstable neurological syndromes and in patients with major stroke,5 there is no evidence of an increased operative risk in stable patients with TIA or nondisabling stroke who are operated on within the first week after their presenting event.4,5 In endarterectomy, we certainly therefore have a treatment that is highly effective in reducing the early risk of recurrent stroke but which is not currently being performed sufficiently quickly.
There is therefore no doubt that TIA and minor stroke deserve emergency status. Whether changing the name to threatening infarct of the brain (TIB), as suggested by Dr Hoffmann, or alternatively to impending stroke syndrome or emergency prestroke syndrome is uncertain. What we do need is more research, particularly randomized trials of preventive treatment, to demonstrate to colleagues that delays in investigation and treatment are negligent, and more public education to persuade people to take transient neurological symptoms very seriously.
Lovett JK, Coull A, Rothwell PM, on behalf of the Oxford Vascular Study. Early risk of recurrent stroke by aetiological subtype: implications for stroke prevention.Neurology. In press.
Rothwell PM, Gutnikov SA, Eliasziw M, Fox AJ, Taylor W, Mayberg MR, Warlow CP, Barnett HJM, for the Carotid Endarterectomy Trialists’ Collaboration. Pooled analysis of individual patient data from randomised controlled trials of endarterectomy for symptomatic carotid stenosis. Lancet. 2003; 361: 107–116.
Rothwell PM, Eliasziw M, Gutnikov SA, Warlow CP, Barnett HJM, for the Carotid Endarterectomy Trialists’ Collaboration. Effect of endarterectomy for symptomatic carotid stenosis in relation to clinical subgroups and the timing of surgery.Lancet. 2003. In press.
Bond R, Rerkasem K, Rothwell PM. A systematic review of the risks of carotid endarterectomy in relation to the clinical indication and the timing of surgery. Stroke. 2003; 34: 2290–2301.