title: Association of type 2 diabetes with brain atrophy and cognitive impairment.
abstract: OBJECTIVE
  We investigated the associations of diabetes and hypertension with imaging biomarkers (markers of neuronal injury and ischemic damage) and with cognition in a population-based cohort without dementia.
  
  
  METHODS
  Participants (n = 1,437, median age 80 years) were evaluated by a nurse and physician and underwent neuropsychological testing. A diagnosis of cognitively normal, mild cognitive impairment (MCI), or dementia was made by an expert panel. Participants underwent MRI to determine cortical and subcortical infarctions, white matter hyperintensity (WMH) volume, hippocampal volume (HV), and whole brain volume (WBV). The medical records were reviewed for diabetes and hypertension in midlife or later.
  
  
  RESULTS
  Midlife diabetes was associated with subcortical infarctions (odds ratio, 1.85 [95% confidence interval, 1.09-3.15]; p = 0.02), reduced HV (-4% [-7 to -1.0]; p = 0.01), reduced WBV (-2.9% [-4.1 to -1.6]), and prevalent MCI (odds ratio, 2.08; p = 0.01). The association between diabetes and MCI persisted with adjustment for infarctions and WMH volume but was attenuated after adjustment for WBV (1.60 [0.87-2.95]; p = 0.13) and HV (1.82 [1.00-3.32]; p = 0.05). Midlife hypertension was associated with infarctions and WMH volume and was marginally associated with reduced performance in executive function. Effects of late-life onset of diabetes and hypertension were few.
  
  
  CONCLUSIONS
  Midlife onset of diabetes may affect late-life cognition through loss of brain volume. Midlife hypertension may affect executive function through ischemic pathology. Late-life onset of these conditions had fewer effects on brain pathology and cognition.
authors.affiliation: From the Division of Epidemiology, Department of Health Sciences Research (R.O.R, M.M.M, Y.E.G., W.A.R., R.C.P.), Division of Biomedical Statistics and Informatics, Department of Health Sciences Research (S.A.P., V.S.P.), and Departments of Neurology (R.O.R., D.S.K., B.F.B., W.A.R., R.C.P.), Radiology (K.K., G.M.P., M.L.S., C.R.J.), and Psychiatry & Psychology (R.J.I.), Mayo Clinic, Rochester, MN; and Departments of Psychiatry & Psychology (Y.E.G.) and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors.forename: Rosebud O
authors.initials: RO
authors.lastname: Roberts
authors.forename: David S
authors.initials: DS
authors.lastname: Knopman
authors.forename: Scott A
authors.initials: SA
authors.lastname: Przybelski
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Mielke
authors.forename: Kejal
authors.initials: K
authors.lastname: Kantarci
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Preboske
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Senjem
authors.forename: Vernon S
authors.initials: VS
authors.lastname: Pankratz
authors.forename: Yonas E
authors.initials: YE
authors.lastname: Geda
authors.forename: Bradley F
authors.initials: BF
authors.lastname: Boeve
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Ivnik
authors.forename: Walter A
authors.initials: WA
authors.lastname: Rocca
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Petersen
authors.forename: Clifford R
authors.initials: CR
authors.lastname: Jack
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000453:epidemiology; D008297:Male; D011159:Population Surveillance / Q000379:methods*; D011446:Prospective Studies; D012307:Risk Factors