Medial temporal atrophy but not memory deficit predicts progression to dementia in patients with mild cognitive impairment.
BACKGROUND
The diagnosis of mild cognitive impairment (MCI) is clinically unhelpful, as many patients with MCI develop dementia but many do not.


OBJECTIVE
To identify clinical instruments easily applicable in the clinical routine that might be useful to predict progression to dementia in patients with MCI assessed in the outpatient facility of a memory clinic.


METHODS
52 dementia-free patients (mean (standard deviation) age 70 (6) years; 56% women) with MCI, and 65 healthy controls (age 69 (6) years; 54% women) underwent brain magnetic resonance scan with standardised visual assessment of medial temporal atrophy (MTA) and subcortical cerebrovascular lesions (SVLs). Follow-up assessment occurred 15.4 (SD 3.4) months after baseline to detect incident dementia and improvement, defined as normal neuropsychological performance on follow-up.


RESULTS
Patients were classified into three groups according to the presence of memory disturbance only (MCI Mem), other neuropsychological deficits (MCI Oth) or both (MCI Mem+). MCI Mem and Mem+ showed MTA more frequently (31% and 47% v 5% and 14% of controls and MCI Oth, p<0.001). 11 patients developed dementia (annual rate 16.5%) and 7 improved on follow-up. The only independent predictor of progression was MTA (odds ratio (OR) 7.1, 95% confidence interval (CI) 1.4 to 35.0), whereas predictors of improvement were the absence of memory impairment (OR 18.5, 95% CI 2.0 to 171.3) and normal MRI scan (OR 10.0, 95% CI 1.7 to 60.2).


CONCLUSIONS
Neuropsychological patterns identify groups of patients with MCI showing specific clinical features and risk of progression to dementia. MTA clinically rated with a visual scale is the most relevant predictor of progression and improvement.
Geroldi
C
C
Laboratory of Epidemiology, Neuroimaging and Telemedicine, IRCCS San Giovanni di Dio FBF-The National Center for Research and Care of Alzheimer's Disease, via Pilastroni 4, 25125 Brescia, Italy. cgeroldi@fatebenefratelli.it
Rossi
R
R
Calvagna
C
C
Testa
C
C
Bresciani
L
L
Binetti
G
G
Zanetti
O
O
Frisoni
G B
GB
D000368:Aged; D000544:Alzheimer Disease / Q000503:physiopathology*; D001284:Atrophy; D003072:Cognition Disorders / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders; D008609:Mental Status Schedule; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D013702:Temporal Lobe / Q000473:pathology*