BackgroundThe contribution of glycemic variability to macrovascular complications remains unclear. We therefore investigated the association between glycemic variability and cervical and/or intracranial atherosclerosis in Chinese type 2 diabetic patients.MethodsWe conducted a cross-sectional study in 216 type 2 diabetic patients with a hemoglobin A1c of 8.3 ± 1.7% and a median diabetes duration of 9.0 years. The standard deviation of blood glucose values (SDBG) and the mean amplitude of glycemic excursion (MAGE) were calculated from continuous glucose monitoring system data for assessing glycemic variability while 24h mean blood glucose (MBG) was calculated for measuring overall blood glucose level. Magnetic resonance angiography (MRA) was used to detect cervical and/or intracranial plaque, and ultrasonography was used to quantify carotid intima-media thickness (IMT) as an index of subclinical atherosclerosis.ResultsOne hundred and fifty-three patients (70.8%) presented with cervical and/or intracranial lesions on MRA among 216 patients in the study. Elder age, increased systolic blood pressure, increased MBG and elevated low density lipoprotein cholesterol were independent contributors to plaque formation. In patients without stenosis (n = 63), SDBG (r = 0.412, P = 0.001) and MAGE (r = 0.365, P = 0.005) were both correlated with carotid IMT and these relationships remained significant in multiple linear regression analysis (multiple R2 = 0.314 for the model including SDBG and multiple R2 = 0.268 for the model including MAGE). However, SDBG and MAGE were not significantly different among patients with different stenosis degrees.ConclusionsGlycemic variability is associated with subclinical atherosclerosis in Chinese type 2 diabetic patients.