Type 2 diabetes is associated with a worse functional outcome of ischemic stroke

To assess whether ischemic stroke severity and outcome is more adverse in patients with type 2 diabetes mellitus (T2DM).

Consecutive patients hospitalized for acute ischemic stroke between September 2010 and June 2013 were studied prospectively (n = 482; 40.2% males, age 78.8 ± 6.7 years). T2DM was defined as self-reported T2DM or antidiabetic treatment. Stroke severity was evaluated with the National Institutes of Health Stroke Scale (NIHSS) score at admission. The outcome was assessed with the modified Rankin scale (mRS) score at discharge and with in-hospital mortality. Adverse outcome was defined as mRS score at discharge ≥ 2 or in-hospital death. The length of hospitalization was also recorded.

T2DM was present in 32.2% of the study population. Patients with T2DM had a larger waist circumference, higher serum triglyceride and glucose levels and lower serum high-density lipoprotein cholesterol levels as well as higher prevalence of hypertension, coronary heart disease and congestive heart failure than patients without T2DM. On the other hand, diabetic patients had lower low-density lipoprotein cholesterol levels and reported smaller consumption of alcohol than non-diabetic patients. At admission, the NIHSS score did not differ between patients with and without T2DM (8.7 ± 8.8 and 8.6 ± 9.2, respectively; P = NS). At discharge, the mRS score also did not differ between the two groups (2.7 ± 2.1 and 2.7 ± 2.2 in patients with and without T2DM, respectively; P = NS). Rates of adverse outcome were also similar in patients with and without T2DM (62.3% and 58.5%, respectively; P = NS). However, when we adjusted for the differences between patients with T2DM and those without T2DM in cardiovascular risk factors, T2DM was independently associated with adverse outcome [relative risk (RR) = 2.39; 95%CI: 1.21-4.72, P = 0.012]. In-hospital mortality rates did not differ between patients with T2DM and those without T2DM (9.0% and 9.8%, respectively; P = NS). In multivariate analysis adjusting for the difference in cardiovascular risk factors between the two groups, T2DM was again not associated with in-hospital death.

T2DM does not appear to affect ischemic stroke severity but is independently associated with a worse functional outcome at discharge.