Subjective memory complaints are not Sine Qua Non as diagnostic criteria for MCI: The Tajiri Project

Background: To investigate whether subjective memory complaints are sine qua non as diagnostic criteria for mild cognitive impairment (MCI), a comprehensive approach is required. Information from a memory clinic and an epidemiologic field are required, and both are available in the Tajiri Project. Methods: We report two MCI cases, one of a patient complaining of memory decline, and the other of a patient without such complaints. Also, epidemiologic data were obtained from the healthy and MCI groups, and we analyzed the relationship between the Everyday Memory Checklist scores obtained from the participants and their families. Results: For both cases, MRI were compatible with Alzheimer's disease (AD), and the both actually progressed to clinical AD. Based on the epidemiologic survey, two patterns emerged regarding the relationship between subjective complaints and family observations: the "anosognosia" pattern associated with the memory questions, and the "self-recognition" pattern related to the questions on communication problems. Conclusions: The case studies and the epidemiologic data suggest that subjective memory complaints have no significant meaning for distinguishing MCI patients from healthy subjects. Hence, we consider that subjective memory complaints are not sine qua non as diagnostic criteria for MCI.