Increased cortical atrophy in patients with Alzheimer's disease and type 2 diabetes mellitus.
BACKGROUND
The risk of Alzheimer's disease (AD) is increased in type 2 diabetes (DM2). This increased risk has been attributed to vascular comorbidity, but other mechanisms, such as accelerated ageing of the brain, have also been implicated.


OBJECTIVE
To determine whether AD in patients with DM2 is associated with an increased occurrence of vascular lesions in the brain, by increased cerebral atrophy, or a combination of both.


METHODS
In total, 29 patients with AD and DM2 and 58 patients with AD and without DM2 were included in the study. Clinical characteristics were recorded, and a neuropsychological examination and magnetic resonance imaging (MRI) scan were performed. MRI scans were rated for cortical and subcortical atrophy, medial temporal lobe atrophy, white matter lesions, and infarcts.


RESULTS
The neuropsychological profiles of the two groups were identical. Patients with AD and DM2 had increased cortical atrophy on MRI (p<0.05) compared with the non-DM2 group. In addition, infarcts were more common (odds ratio 2.4; 95% CI 0.8 to 7.8), but this effect did not account for the increased atrophy. The other MR measures did not differ between the groups.


CONCLUSIONS
The results suggest that non-vascular mechanisms, leading to increased cortical atrophy, are also involved in the increased risk of AD in DM2.
The Alzheimer Center, Department of Neurology, VU Medical Center, Amsterdam, The Netherlands. g.j.biessels@umcutrecht.nl
G J
GJ
Biessels
F-E
FE
De Leeuw
J
J
Lindeboom
F
F
Barkhof
P
P
Scheltens
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000209:etiology / Q000473:pathology*; D001284:Atrophy; D001921:Brain; D002540:Cerebral Cortex / Q000473:pathology*; D002544:Cerebral Infarction / Q000175:diagnosis / Q000473:pathology; D015897:Comorbidity; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011594:Psychometrics / Q000706:statistics & numerical data; D013223:Statistics as Topic; D013702:Temporal Lobe / Q000473:pathology