Subjective cognitive complaints in cognitively unimpaired Parkinson's disease: Associations with affective burden, motor severity, and awareness-related processes.

BACKGROUND: Subjective cognitive complaints (SCC) are frequent in Parkinson's disease (PD), but their significance in cognitively unimpaired individuals remains uncertain. OBJECTIVES: To investigate the frequency of SCC in cognitively unimpaired PD patients and examine associations with objective cognition, mood symptoms, and anosognosia. METHODS: In this cross-sectional study, 74 PD patients with preserved cognitive performance based on the Addenbrooke's Cognitive Examination-Revised (ACE-R) were included. SCC were assessed using the Prospective and Retrospective Memory Questionnaire (PRMQ-10). Mood symptoms were measured with the Hospital Anxiety and Depression Scale (HADS). Associations were analyzed using nonparametric tests, correlations, and multivariable linear regression. Anosognosia was estimated using a subjective-objective discrepancy index. RESULTS: SCC were present in 36 participants (48.6%). SCC status was not associated with ACE-R total or memory scores. SCC+ participants showed higher affective symptom burden and greater motor severity. PRMQ-10 scores correlated with HADS measures, particularly depressive symptoms. In adjusted models, SCC status showed a modest positive association with ACE-R total scores. No descriptive evidence of systematic discrepancy between subjective and objective memory measures was observed. CONCLUSIONS: SCC were highly prevalent in cognitively unimpaired PD and were more strongly associated with affective burden and motor severity than with objective cognitive performance.