Background: Elevated body temperature is a known marker of poor outcome in stroke. Some studies have shown that elevated body temperature early in the course of stroke is associated with better outcomes. We sought to characterize the relationship of body temperature and long-term clinical outcomes by evaluating serial measurements over 24 hours.
Methods: All subjects were enrolled <2 hours after stroke symptom onset into the Phase 3 NIH Field Administration of Stroke Therapy Magnesium (FAST-MAG) clinical trial testing magnesium for prehospital neuroprotection. Presenting temperature in the emergency room and follow-up temperatures at 8, 16 and 24 hours after arrival were recorded. Clinical outcome was measured using the modified Rankin Scale at 90 days with last observation carried forward. Mean temperature was compared for each outcome on the modified Rankin Scale (mRS) utilizing ANOVA.
Results: Among the 1700 enrolled patients 1586 (93%) had temperature recorded on ED arrival, 1594 at 8 hours, 1611 at 16 hours, 1594 at 24 hours. Mean age was 69 years, 43% were women, final diagnosis cerebral ischemia in 73.3%, intracranial hemorrhage in 22.8%, and mimic in 3.9%. At presentation mean body temperature was higher among those experiencing better long-term outcomes (Figure 1A). As of 8 hours and continuing through all subsequent measures worse outcome across the modified Rankin Scale spectrum was associated with higher body temperature (Figure 1B-D).
Conclusions: Although higher body temperature at presentation was noted in subjects achieving better long-term outcomes, subsequent measures as of 8 hours demonstrated higher body temperatures in those experiencing worse long-term outcomes.