Patients with Alzheimer's disease (AD), namely at an initial stage like amnestic cognitive impairment (aMCI), typically present with memory complaints. They also have difficulties regarding self-knowledge about their cognitive deficits. In clinical practice, a formal neuropsychological assessment is often done. The present study aimed to understand whether patients with aMCI retain the ability to monitor the success or failure in their performance during the neuropsychological assessment and adjust the report of memory complaints accordingly, as compared to healthy controls.
Participants were patients with aMCI and healthy controls who were questioned about their own memory abilities using the Subjective Memory Complaints (SMC) scale, applied before and after the neuropsychological assessment protocol. A repeated measures General Linear Model was performed to analyze changes in SMC (within-subjects effects) after the neuropsychological assessment, in patients with aMCI and healthy controls (between-subjects effects).
Eighty volunteers, 40 patients with aMCI and 40 healthy controls, participated in the study. Patients with aMCI showed lower MMSE scores, more depressive symptoms, and deficits in memory and learning, language and executive domains. Patients with aMCI had higher SMC scores [9.4(3.6)] than healthy controls [4.4(2.3)] before the neuropsychological assessment. A statistically significant interaction was found between the SMC and the diagnostic group, meaning that healthy controls decreased SMC [3.4(1.9)] after the neuropsychological assessment, whereas patients with aMCI kept high levels of SMC [9.6(3.9)]. In patients with aMCI, an inverse correlation between logical memory and the change in SMC was found, so that patients with lower scores in the logical memory test tended to increase their memory complaints after the assessment.
Both patients with aMCI and healthy controls can monitor and update the impression about their memory abilities following a formal neuropsychological assessment. Patients with aMCI maintain a high SMC level, which is inversely associated with their memory performance. In practical terms, SMC should be measured consistently at a particular moment in time, preferably preceding the objective neuropsychological assessment.