Self-awareness of memory function in Parkinson's disease in relation to mood and symptom severity

In clinical practice, discrepancies are observed between self and proxy reports of various aspects of Parkinson's disease (PD). This study aimed at assessing self-awareness of memory function in PD both by comparing patients' and caregivers' questionnaire ratings of the patients' memory and by correlating subjective ratings with verbal learning results.

Forty-five patient-proxy pairs participated in the study. Self-Rating Scale of Memory Functions was used as a questionnaire subjective measure. Auditory Verbal Learning Test (AVLT) was applied to assess verbal memory, Stroop test to assess cognitive control and Mini-Mental State Examination (MMSE) for global cognitive assessment.

Patient self-reports did not diverge appreciably from proxy reports when global scores were considered, but patient-proxy consistency was low for individual items with the exception of those referring to verbal recall. Both patient and proxy ratings were moderately correlated with the objective measures. Patient-proxy discrepancies were associated with lower verbal learning, poor cognitive control and more severe PD symptomatology. Moreover, depression was associated with patients' overestimation of symptoms.

Self-awareness of memory function is relatively well preserved in PD, but is negatively affected by depressive symptoms. Patient-proxy discrepancies increase also with disease severity, degree of memory problems and cognitive control deficits. Caregivers seem to be unaware of the specificity of memory problems in PD and report only some of them, mainly those related to verbal recall.