An analysis of communication in conversation in patients with dementia.

Patients with degenerative dementia often show language disorders, but little is known about their verbal (VC) and non-verbal communication (NVC). Our aim was to analyse VC and NVC in patients with standard criteria of mild-moderately severe dementia (MMSE ≥14/30) resulting from Alzheimer's disease (AD; 29 cases), behavioural variant of frontotemporal dementia (FTD; 16), or dementia with Lewy bodies (DLB; 13). We used the Lille Communication Test, which addresses three domains: participation in communication (PC: greeting, attention, participation), VC (verbal comprehension, speech outflow, intelligibility, word production, syntax, verbal pragmatics and verbal feedback), and NVC (understanding gestures, affective expressivity, producing gestures, pragmatics and feedback). Patients were compared with 47 matching control subjects. AD patients were partially impaired (p≤0.01) in PC (greeting), and more definitely in VC, especially by verbal comprehension and word finding difficulties and to a much lesser degree in verbal pragmatics (responding to open questions, presenting new information), while NVC was mostly preserved. FTD patients were severely impaired in PC. VC difficulties were related to lexical-semantic, syntactic and more specifically pragmatic problems. NVC was impaired by difficulties in affective expressivity, pragmatics and feedback management. DLB patients showed modest difficulties with VC. PC, VC and NVC strongly correlated with performance in the dementia rating scale. In conclusion, the profile of communication difficulties was quite different between groups. FTD patients showed most severe difficulties in PC and verbal and non-verbal pragmatics, in relation to their frontal lesions. AD patients had prominent impairment of lexical-semantic operations.