Metabolic and vascular determinants of impaired cognitive performance and abnormalities on brain magnetic resonance imaging in patients with type 2 diabetes

Diabetologia. 2007 Nov;50(11):2388-97. doi: 10.1007/s00125-007-0792-z. Epub 2007 Sep 2.


Aims/hypothesis: The determinants of cerebral complications of type 2 diabetes are unclear. The present study aimed to identify metabolic and vascular factors that are associated with impaired cognitive performance and abnormalities on brain MRI in patients with type 2 diabetes.

Methods: The study included 122 patients and 56 controls. Neuropsychological test scores were divided into five cognitive domains and expressed as standardised z values. Brain MRI scans were rated for white matter lesions (WML), cortical and subcortical atrophy, and infarcts. Data on glucose metabolism, vascular risk factors and micro- and macrovascular disease were collected.

Results: Patients with type 2 diabetes had more cortical (p < 0.001) and subcortical (p < 0.01) atrophy and deep WML (p = 0.02) than the control group and their cognitive performance was worse. In multivariate regression analyses within the type 2 diabetes group, hypertension (p < 0.05) and a history of vascular events (p < 0.01) were associated with worse cognitive performance, while statin use was associated (p < 0.05) with better performance. Retinopathy and brain infarcts on MRI were associated with more severe cortical atrophy (both p < 0.01) and statin use with less atrophy (p < 0.05). Insulin level and brain infarcts were associated with more severe WML and statin use with less severe WML (all p < 0.05).

Conclusions/interpretation: Type 2 diabetes is associated with modest impairments in cognition, as well as atrophy and vascular lesions on MRI. This 'diabetic encephalopathy' is a multifactorial condition, for which atherosclerotic (macroangiopathic) vascular disease is an important determinant. Chronic hyperglycaemia, hyperinsulinaemia and hypertension may play additional roles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Brain / pathology*
  • Brain Mapping
  • Cognition Disorders / blood
  • Cognition Disorders / metabolism*
  • Cognition Disorders / pathology
  • Diabetes Mellitus, Type 2 / pathology*
  • Diabetes Mellitus, Type 2 / physiopathology
  • Diabetes Mellitus, Type 2 / psychology
  • Diabetic Angiopathies / pathology
  • Diabetic Angiopathies / physiopathology*
  • Diabetic Angiopathies / psychology
  • Diabetic Neuropathies / pathology
  • Diabetic Neuropathies / physiopathology
  • Diabetic Neuropathies / psychology
  • Female
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • Reference Values