Reevaluation of transient ischemic attacks as a risk factor for early mortality.

Abstract

The prevailing belief that transient ischemic attack is a risk factor for cardiovascular morbidity and mortality is based primarily on comparisons of survival of patients after transient ischemic attacks to that of an age-, race-, and sex-adjusted general population. Concomitant conditions that carry a high risk of premature mortality or morbidity, such as ischemic heart disease, hypertension, and diabetes, are very prevalent among patients with transient ischemic attacks. Hence, the poor prognosis of such patients may be attributable to these factors rather than their transient ischemic attack per se, which may only serve to bring patients into the medical system. We compared the survival of 336 patients after transient ischemic attack to that of a control group with a similar risk factor profile consisting of 6,710 patients evaluated for cardiac catheterization. Survival estimates, both unadjusted and adjusted for risk factors, did not differ between the two groups. Three-year survival estimates, after adjustment to the mean value of covariates, were 94% for the patients with transient ischemic attacks and 91% for the controls. These results suggest that the transient ischemic attack may not be an independent risk factor for mortality, although it may identify patients already at increased risk from coexisting conditions. {Stroke 1991;22:582-585) A long ago as the early 1950s, Fisher and Cameron 1 expressed a concern that transient ischemic attacks (TTAs) were associated with an increased risk of cerebrovascular events. Such comments initially stressed the increased risk of stroke in TLA patients, but at that time, or indeed today, there were no reliable estimates of the expected incidence of stroke in the general population. Although the stroke rate in the TLA. population could be estimated from available data on TIA patients, without knowledge of the stroke rate in the general population, the excess risk of stroke associated with TIA could not be estimated.Many authors, including ourselves, contrasted the survival of TIA patients to that of an age-, race-, and sex-matched general population.2 -8 These reports generally showed the survival of TIA patients to be significantly worse than would be expected in the general population and the cause of death in the TIA Received August 29, 1990; accepted January 11, 1991. population to be most often coronary, rather than cerebrovascular, disease. However, based on data from the Cooperative Study of Transient Ischemic Attacks 9 and our own TIA population, 8 TIA patients have a significantly higher prevalence of cerebrovascular and coronary heart disease risk factors, including hypertension, ischemic heart disease, diabetes, cigarette smoking, and previous stroke, than is present in the general population. We have shown previously 8 in our TIA cohort that patients with none of these risk factors, and even TIA patients with a single risk factor, fare as well as the age-, race-, and sex-matched general population. In contrast, those TIA patients with two or more of th...

A prospective reevaluation of transient ischemic attacks as a risk factor for death and fatal or nonfatal cardiovascular events.

“…The nonsignificant difference in death rate confirms the findings from our earlier retrospective study. 8 The estimated hazard ratio for death was approximately 1.4. That there was an excess of both stroke and MI (fatal or nonfatal) in the TIA group would, of course, suggest there should be increased risk of death.…”

“…Recently we retrospectively compared the survival of a cohort of 336 TIA patients with a group of patients with a similar risk factor burden and found no excess mortality associated with TIAs. 8 This comparison suggested that TIAs may not be strongly predictive for all-cause mortality, although they may identify patients already at increased risk from coexisting conditions.…”

Clinical Predictors for Early Mortality of Patients with Acute Basilar Artery Occlusion

“…Most death occurs within the first 7 days of hospitalization [4]. Factors that have a significant impact on in-hospital mortality have been assessed in acute anterior circulation large vessel occlusion [4][5][6][7][8]. Modifiable (neurological and medical complications) and nonmodifiable factors (demographic and clinical parameters and comorbidities) that have an independent impact on in-hospital mortality of patients with acute BAO have not been determined.…”