title: Usefulness of an Integrated Analysis of Different Memory Tasks to Predict the Progression from Mild Cognitive Impairment to Alzheimer's Disease: The Episodic Memory Score (EMS).
abstract: Taking into the account both the severity and the consistency of performances obtained on memory tests by patients with amnestic mild cognitive impairment (aMCI) could improve the power to predict their progression to Alzheimer's disease. For this purpose, we constructed the Episodic Memory Score (EMS), which is obtained by subdividing in tertiles performances obtained at baseline in verbal (RAVLT) and visual episodic memory (Rey-Osterrieth Figure-delayed recall) and giving a score ranging from 1 (worst result) to 3 (best result) to results falling within each tertile. The EMS was computed for each patient by summing the tertile score obtained on each memory task, so that the total score ranged from 4 (worst performance) to 12 (best performance). The aMCI sample consisted of 198 subjects who completed the two-year follow-up, at the end of which 55 subjects had converted to dementia. The mean EMS score obtained by aMCI converters was significantly lower than that of aMCI-stable patients. In detecting conversion to dementia, the comparison between EMS and individual memory scores obtained at baseline was made by computing ROC curves, and estimating the respective area under the curve (AUC). The EMS had a larger AUC than the individual memory scores. At baseline aMCI converters performed worse than non-converters not only on memory tasks, but also on executive functions tasks. However, in a multiple variables logistic regression analysis in which all scores showing statistically significant differences between aMCI-converters and aMCI-stable were entered, the EMS was the only reliable predictor of progression from aMCI to dementia.
authors.affiliation: Center for Neuropsychological Research, Institute of Neurology of the Policlinico Gemelli/Catholic University of Rome, Italy.
authors.forename: Camillo
authors.initials: C
authors.lastname: Marra
authors.affiliation: Center for Neuropsychological Research, Institute of Neurology of the Policlinico Gemelli/Catholic University of Rome, Italy.|IRCCS Fondazione Santa Lucia, Department of Clinical and Behavioral Neurology, Rome, Italy.
authors.forename: Guido
authors.initials: G
authors.lastname: Gainotti
authors.affiliation: IRCCS Fondazione Santa Lucia, Department of Clinical and Behavioral Neurology, Rome, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Fadda
authors.affiliation: IRCCS Fondazione Santa Lucia, Department of Clinical and Behavioral Neurology, Rome, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Perri
authors.affiliation: Center for Neuropsychological Research, Institute of Neurology of the Policlinico Gemelli/Catholic University of Rome, Italy.
authors.forename: Giordano
authors.initials: G
authors.lastname: Lacidogna
authors.affiliation: Center for Neuropsychological Research, Institute of Neurology of the Policlinico Gemelli/Catholic University of Rome, Italy.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Scaricamazza
authors.affiliation: Center for Neuropsychological Research, Institute of Neurology of the Policlinico Gemelli/Catholic University of Rome, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Piccininni
authors.affiliation: Center for Neuropsychological Research, Institute of Neurology of the Policlinico Gemelli/Catholic University of Rome, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Quaranta
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000503:physiopathology*; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000503:physiopathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D061212:Memory, Episodic; D011939:Mental Recall; D009483:Neuropsychological Tests; D012372:ROC Curve
keywords: Alzheimer’s disease; Rey-Osterrieth Complex Figure delayed reproduction; amnestic mild cognitive impairment; conversion; integration of memory scores; neuropsychological markers; verbal immediate and delayed recall