Memory complaints in mild cognitive impairment, worried well, and semantic dementia patients

Complaints related to memory are characteristic of normal ageing, affective disorders, and are a cardinal feature of amnestic mild cognitive impairment (aMCI), the proposed prodrome to Alzheimer disease proper. The aim of this study was to investigate the profile of subjective memory complaints in different cognitive syndromes. Subjective memory was assessed using the Cambridge Memory Complaints Questionnaire consisting of 20 questions about everyday aspects of memory. This was completed by 22 "worried well" (WW), 85 aMCI, and 40 semantic dementia (SD) patients at first presentation to a memory clinic. All patients were followed up for 2 years. A principal component factor analysis revealed 5 principal factors pertaining to working, episodic, topographical, and semantic memory. All factors, except topographical memory, reliably differentiated SD patients from other groups, with aMCI and WW patients complaining significantly more about working and episodic memory, and SD patients complaining significantly more about semantic memory. WW and aMCI patients, however, could not be differentiated, even those aMCI patients who progressed to dementia. Memory complaints are strikingly similar to the description of typical core deficits in SD patients. The sole reliance on memory complaints for insight into memory functioning and diagnosing aMCI is problematic.