Presentation of three French screening tools to detect the lexico-semantic breakdown in mild cognitive impairment and Alzheimer's disease

Lexico-semantic difficulties are amongst the first symptoms of Alzheimer's disease (AD). Lexical impairment manifests itself through word retrieval difficulties while semantic disorder impairs general knowledge. This profile already occurs in mild cognitive impairment (MCI), constituting a predictive feature of conversion in AD. The aim of this study is to present three tools to rapidly screen lexical and semantic disorder. 97 participants allocated in 3 groups contributed to this Belgian-Quebec study: one group of MCI (N=35, MOCA for French-Canadian =24.18+/-2.3 ; MMSE for Belgian =26.71+/-1.38), one group of AD (N=13, MMSE=24.7+/-2.52) and one control group (N=49, MOCA for French-Canadian=27.79+-1.9 ; MMSE for Belgian=29.07+/-.79). Three tools were administered : 1) the mini Semantic Knowledge Questionnaire (SKQ) composed of 12 multiple choice questions interrogating semantic properties of objects ; 2) The Short Test of naming for Alzheimer's Disease (STN-AD) comprising 11 pictures in black and white to name and 3) the mini-Montreal Semantic Memory Protocol (mini-MSMP) comprising 26 questions interrogating functional or categorical features of objects. The ANOVA indicated that all the three tools (mini-SKQ : F(2 ;94)=8.440 ; p<.001 ; STN-AD : F(2 ;94)=17.760 ; p<.001; mini-MSMP: F(2 ;94)=7.273 ; p=.001) allowed for differentiating our groups. Post hoc tests (Bonferroni) showed that MCI and AD performed poorer than the control group for all three tools (p<.05). The mini-SQK, the STN-AD and the mini-MSMP are three original tools used to evaluate the early lexical and semantic alteration. Their rapid administration made them instrument of choice for an early detection of MCI and AD.