Abstract

Objective: To examine the association of glycemic status to Magnetic Resonance Imaging indicators of brain pathology.

Objective: Research Design & Setting: Cross-sectional, population-based study of 4,415 non-demented men and women (mean age = 76 years) participating in the Age Gene/Environment Susceptibility-Reykjavik Study. Glycemic status groups included: T2D [self-report of diabetes, use of diabetic medications, or fasting blood glucose ≥7.0 mmol/l (11.1%)]; impaired fasting glucose (IFG) [fasting blood glucose 5.6-6.9 mmol/l, n=744 (36.2%)]; and normoglycemic (57.7%). Outcomes were total brain, white and grey matter volume, white matter lesion (WML) volume and presence of cerebral infarcts.

Results: Adjusting for demographic and cardiovascular risk factors, compared to normoglycemic subjects, those with T2D had significantly lower total brain volume (72.2% vs 71.5%; p<0.001) and lower grey and white matter volume (45.1% vs. 44.9%, p<0.01 and 25.7% vs 25.3%, p<0.001, respectively) and were more likely to have a single (OR = 1.45; 95% CI 1.14, 1.85) or multiple (OR = 2.27; 95% CI 1.60, 3.23) cerebral infarct(s). Longer duration of T2D was associated with lower total brain volume, grey and white matter volume, higher WML volume (all p's for trend = <0.05) and a greater likelihood of single and multiple cerebral infarcts (all p's for trend <0.01).

Conclusions: Type 2 diabetics have more pronounced brain atrophy and are more likely to have cerebral infarcts. Duration of T2D is associated with brain changes suggesting that T2D has a cumulative effect on the brain.