Insulin resistance and classic risk factors in type 2 diabetic patients with different subtypes of ischemic stroke.
OBJECTIVE
In addition to classic risk factors (e.g., hypertension), insulin resistance is an important risk factor for the development of atherosclerosis. To investigate the risk factors for ischemic stroke in type 2 diabetes, we measured insulin sensitivity and several risk factors in 94 Japanese type 2 diabetic patients with different types of stroke.


METHODS
Stroke was classified by magnetic resonance imaging (MRI) and magnetic resonance (MR) angiography into the following subtypes: 1) patients with normal MRI and MR angiography (NOR; n = 30), 2) patients with lacunar infarction (LAC; n = 28), 3) patients with atherothrombotic infarction (ATI; n = 22), and 4) patients with large-artery atherosclerosis (LAA; n = 14). Insulin sensitivity was assessed by the K index of the insulin tolerance test (KITT).


RESULTS
Patients with LAC, ATI, and LAA were significantly older and were more likely to be hypertensive than patients with NOR. Significantly higher insulin resistance was observed in patients with LAC, ATI, and LAA than in patients with NOR (KITT 2.21 +/- 0.17, 2.10 +/- 0.17, 2.19 +/- 0.25, and 3.25 +/- 0.21% per min, respectively, P < 0.001). Adjustment for age, sex, BMI, and duration of diabetes did not influence this result. Multiple logistical regression analysis showed that insulin resistance was an independent risk factor for all subtypes of ischemic stroke in type 2 diabetic patients. The same analysis showed that a high pulse pressure was a risk factor for LAC, postprandial C-peptide (hyperinsulinemia) was a risk factor for ATI, and longstanding hyperglycemia was a risk factor for LAA.
Matsumoto
K
K
Department of Internal Medicine, Sasebo Chuo Hospital, Nagasaki, Japan.
Miyake
S
S
Yano
M
M
Ueki
Y
Y
Miyazaki
A
A
Hirao
K
K
Tominaga
Y
Y
D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D002545:Brain Ischemia / Q000145:classification* / Q000453:epidemiology* / Q000503:physiopathology; D002544:Cerebral Infarction / Q000145:classification / Q000453:epidemiology* / Q000503:physiopathology; D003072:Cognition Disorders / Q000453:epidemiology; D003327:Coronary Disease / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000453:epidemiology / Q000503:physiopathology*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D007333:Insulin Resistance; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000453:epidemiology; D008875:Middle Aged; D012044:Regression Analysis; D012307:Risk Factors; D012907:Smoking
D006442:Glycated Hemoglobin