SITS-ISTR highlights hyperglycemia impact on thrombolysis outcomes
MedWire News: Admission hyperglycemia is a strong predictor of symptomatic intracerebral hemorrhage (ICH) and poor functional outcome among stroke patients undergoing thrombolysis, shows an analysis of the SITS-ISTR.
"These results suggest that tight control of blood glucose may be indicated in the hyperacute phase following thrombolysis," say Niaz Ahmed (Karolinska Institutet, Stockholm, Sweden) and colleagues.
At the time of the study, the SITS-ISTR (Safe Implementation of Treatments in Stroke International Stroke Thrombolysis Register) contained data on 16,049 patients, 15,336 (95.6%) of whom had blood glucose levels measured on admission.
Overall, each 10-mg/dl increase in admission glucose was associated with a 4% increase in the risk for symptomatic ICH, defined as at least a 4-point deterioration in National Institutes of Health Stroke Scale score within 24 hours of thrombolysis plus type 2 parenchymal hemorrhage.
Each 10-mg/dl increase was also associated with a 3% increase in the risk for dying within 3 months and a 4% decrease in the likelihood of achieving functional independence at 3 months (modified Rankin Scale 0-2).
"Robust hyperglycemia after stroke is a short-lived phenomenon in many patients, especially those without a history of diabetes, as the initial hyperglycemia often normalizes rapidly during the first 10 hours," comment Ahmed et al in the Archives of Neurology.
"Therefore, confirmation of the association between hyperacute hyperglycemia with long-term outcome is of particular relevance."
Compared with admission glucose levels of 80-120 mg/dl, levels above 120 mg/dl were associated with a 24% increase in mortality risk and a 42% reduction in the chances of attaining functional independence.
Levels of 181-200 mg/dl were associated with a 2.86-fold increase in the risk for symptomatic ICH.
In patients with diabetes (17% of the cohort), admission hyperglycemia significantly reduced the likelihood of achieving functional independence. However, the chances of diabetic patients achieving independence only occurred at glucose levels well above those that had a detrimental effect in nondiabetic patients (145 vs 110 mg/dl). Also, hyperglycemia did not affect the risk for symptomatic ICH or mortality in diabetic patients after adjustment for confounders.
The researchers comment that outcomes in diabetic patients were likely influenced by baseline variables, which were generally poorer than in nondiabetic patients. They add that it is "important to note that the association of hyperglycemia with poor outcome was stronger than the history of diabetes."
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By Eleanor McDermid