VIENNA – Patients who have had an ischemic stroke and have high blood sugar levels without being diabetic may be more likely to experience functional impairments than those already diagnosed with diabetes, according to results from a large secondary stroke prevention trial performed in China.
In the trial, conducted at 47 hospitals, high levels of fasting blood glucose (FBG) were associated with worse disability at 6 months in the study, but the association only held in patients who did not have a diagnosis of diabetes at the time of their stroke. The odds ratios for poor functional outcome assessed using the modified Rankin scale (mRS) as a score of greater than 2 versus up to 2 were 1.09 (P = .031) in nondiabetics and 0.98 (P = 0.65) in those previously known to have diabetes.
“We think that a high FBG level after stroke might be better for predicting prognosis in patients without prediagnosed diabetes than in those with diabetes and confirms the importance of glycemic control during the acute phase of ischemic stroke,” said study researcher Dr. Ming Yao of Peking Union Medical College Hospital at the annual European Stroke Conference.Dr. Yao noted that hyperglycemia after an acute stroke had already been linked to poorer clinical outcomes, with reports of larger infarct volumes, an increased risk for secondary hemorrhagic transformation, and lower recanalization rates after thrombolysis. However, it was not clear how functional outcomes were affected or if there was much of difference based on whether or not a patient had diabetes. Data from the Standard Medical Management in Secondary Prevention of Ischemic Stroke in China (SMART) study were therefore used to see what effect high FBG had on functional outcomes in diabetic versus nondiabetic subjects. SMART was a multicenter, cluster-randomized, controlled trial designed to assess the effectiveness of a guideline-based structured care program versus usual care for the secondary prevention of ischemic stroke (Stroke. 2014;45:515-9) and offered a large population of patients for the subgroup analysis. Of the 3,821 patients enrolled in the study, 2,862 had FBG data available and had complete follow-up data at 6 months.
Potential factors related to functional outcome 6 months after a stroke were first identified in the whole cohort using a binary logistic regression model, which categorized outcome as favorable (mRS ≤2) or poor (mRS >2). Univariate and multivariate analyses were then performed to narrow down the variables that might be the most influential.
For the whole cohort, older age (OR = 1.04, P < .001), hypertension (OR = 1.45, P = .028), baseline National Institutes of Health Stroke Scale (NIHSS) score (OR = 1.28, P < .001), and FBG (OR = 1.07, P = .004) were indicative of a poor functional outcome.
Looking at patients with and without diabetes, older age remained predictive of a poorer functional outcome, with respective odds ratios of 1.04 (P = .011) and 1.04 (P < .001). Baseline NIHSS score was also predictive in both patients with diabetes (OR = 1.33, P < .001) and those without (OR = 1.27, P < .001).
“Our present results demonstrate that a higher FBG following stroke is strongly and independently associated with a poor functional outcome,” Dr. Yao observed, “but this association was found only in patients without prediagnosed diabetes.”
The study was study was sponsored by Peking Union Medical College Hospital. Dr. Yao had no conflicts of interest.