Screening for mild cognitive impairment in elderly ambulatory patients with cognitive complaints.
OBJECTIVE
Identification of patients with Mild Cognitive Impairment (MCI) is strongly recommended because of their increased risk of dementia. Two brief global cognitive instruments, the Mini Mental State Examination (MMSE) and the Clock Drawing Test (CDT), were examined as useful screening methods for MCI.


METHODS
The sensitivity and specificity of MMSE and CDT, scored using the Sunderland and Wolf-Klein methods, were evaluated in 113 elderly individuals with three different MCI subtypes: amnestic, multiple domain impairments, and single non-memory domain. Diagnoses were made on the basis of extensive clinical and neuropsychometric assessment.


RESULTS
Used alone, MMSE and CDT at standard cut-offs were highly specific (about 0.80) but rather insensitive (less than 0.50) to all MCI subtypes. By contrast, when used in combination, an abnormal result on either MMSE or CDT scored by the Sunderland method had a specificity of 0.69 [0.57-0.81] and a sensitivity of 0.75 [0.64-0.87] for multiple domain impairments MCI. Results were similar for MMSE in combination with CDT scored by the Wolf-Klein method (specificity 0.71 [0.59-0.83]; sensitivity 0.68 [0.56-0.80]).


CONCLUSIONS
MMSE and CDT alone are not valid screening methods for MCI detection. In combination, they reach fair sensitivity and specificity for the multiple domain impairment MCI subtype. However, some theoretical concerns relating to this subtype, together with the uncertainty that still lingers about its prognostic value, caution against routine use of MMSE and CDT as MCI screening instruments.
Ravaglia
Giovanni
G
Department of Internal Medicine, Cardioangiology and Hepatology, University Hospital S. Orsola-Malpighi, Bologna, Italy. ravaglia@med.unibo.it
Forti
Paola
P
Maioli
Fabiola
F
Servadei
Lucia
L
Martelli
Mabel
M
Brunetti
Nicoletta
N
Bastagli
Luciana
L
Mariani
Erminia
E
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D003704:Dementia / Q000523:psychology; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D009483:Neuropsychological Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity