Diffusion Tensor Imaging Identifies Deficits in White Matter Microstructure in Subjects With Type 1 Diabetes That Correlate With Reduced Neurocognitive Function

Abstract

OBJECTIVE-Long-standing type 1 diabetes is associated with deficits on neurocognitive testing that suggest central white matter dysfunction. This study investigated whether diffusion tensor imaging (DTI), a type of magnetic resonance imaging that measures white matter integrity quantitatively, could identify white matter microstructural deficits in patients with longstanding type 1 diabetes and whether these differences would be associated with deficits found by neurocognitive tests.RESEARCH DESIGN AND METHODS-Twenty-five subjects with type 1 diabetes for at least 15 years and 25 age-and sex-matched control subjects completed DTI on a 3.0 Tesla scanner and a battery of neurocognitive tests. Fractional anisotropy was calculated for the major white matter tracts of the brain.RESULTS-Diabetic subjects had significantly lower mean fractional anisotropy than control subjects in the posterior corona radiata and the optic radiation (P Ͻ 0.002). In type 1 diabetic subjects, reduced fractional anisotropy correlated with poorer performance on the copy portion of the Rey-Osterreith Complex Figure Drawing Test and the Grooved Peg Board Test, both of which are believed to assess white matter function. Reduced fractional anisotropy also correlated with duration of diabetes and increased A1C. A history of severe hypoglycemia did not correlate with fractional anisotropy.CONCLUSIONS-DTI can detect white matter microstructural deficits in subjects with long-standing type 1 diabetes. These deficits correlate with poorer performance on selected neurocognitive tests of white matter function. Diabetes 57:3083-3089, 2008

Brain Changes Underlying Cognitive Dysfunction in Diabetes: What Can We Learn From MRI?

“…More widespread reductions in FA throughout the brain were found in patients with diabetes and microangiopathy (38). In these studies, lower FA in patients was associated with longer diabetes duration (37) and decreased information processing speed and executive functioning (37,38).…”

“…Results showed decreased FA in posterior brain regions compared with control subjects (37). More widespread reductions in FA throughout the brain were found in patients with diabetes and microangiopathy (38).…”

“…Two studies examined microstructural white matter alterations with DTI in middle-aged adults with type 1 diabetes (37,38). Results showed decreased FA in posterior brain regions compared with control subjects (37).…”

Alteration of Interaction Between Astrocytes and Neurons in Different Stages of Diabetes: a Nuclear Magnetic Resonance Study Using [1-13C]Glucose and [2-13C]Acetate

“…Pathological researches have observed significant progressive neuronal losses in the hippocampus in type 1 diabetic rats [6,7]. Studies using magnetic resonance imaging techniques have identified abnormal white matter structure and function as well as reduced gray matter volume and density in diabetic patients [8,9]. All these abnormalities are closely related to brain metabolic disorders [10].…”

“…Decreased glutamine (Gln) supply to gamma-aminobutyric acid (GABA)ergic neurons has been observed in the cortex and subcortex of young epileptic rats, whereas astrocytic metabolism has been increased in adult epileptic rats [22]. Mason et al applied [2][3][4][5][6][7][8][9][10][11][12][13] C]acetate as a tracer to evaluate the hypothesis that patients with type 1 diabetes exhibit increased blood-brain transport and monocarboxylic acid (MCA) metabolism to sustain upregulated MCA transporters during hypoglycemia [23]. 13 C MRS is a primary technique for studying brain metabolism.…”