A higher body temperature is associated with haemorrhagic transformation in patients with acute stroke untreated with recombinant tissue-type plasminogen activator (rtPA)

Higher body temperature is a prognostic factor of poor outcome in acute stroke. Our aim was to study the relationship between body temperature, HT (haemorrhagic transformation) and biomarkers of BBB (blood brain barrier) damage in patients with acute ischaemic stroke untreated with rtPA (recombinant tissue-type plasminogen activator). We studied 229 patients with ischaemic stroke <12 h from symptom onset. Body temperature was determined at admission and every 6 h during the first 3 days. HT was evaluated according to ECASS II (second European Co-operative Acute Stroke Study) criteria in a multimodal MRI (magnetic resonance imaging) at 72 h. We found that 55 patients (34.1%) showed HT. HT was associated with cardioembolic stroke (64.2% against 23.0%; P <0.0001), higher body temperature during the first 24 h (36.9 degrees C compared with 36.5 degrees C; P <0.0001), more severe stroke [NIHSS (National Institutes of Health Stroke Scale) score, 14 (9-20) against 10 (7-15); P = 0.002], and greater DWI (diffusion-weighted imaging) lesion volume at admission (23.2 cc compared with 13.2 cc; P <0.0001). Plasma MMP-9 (matrix metalloproteinase 9) (187.3 ng/ml compared with 44.2 ng/ml; P < 0.0001) and cFn (cellular fibronectin) levels (16.3 mu g/ml compared with 7.1 mu g/ml; P = 0.001) were higher in patients with HT. Body temperature within the first 24 h was independently associated with HT {OR (odds ratio), 7.3 [95% Cl (confidence interval), 2.4-22.6]; P < 0.0001} after adjustment for cardioembolic stroke subtype, baseline NIHSS score and DWI lesion volume. This effect remained unchanged after controlling for MMP-9 and cFn. In conclusion, high body temperature within the first 24 h after ischaemic stroke is a risk factor for HT in patients untreated with rtPA. This effect is independent of some biological signatures of BBB damage.