Unveiling the role of subjective cognitive complaints in predicting cognitive impairment in Parkinson´s Disease- A longitudinal study with 4 year of follow up.

Background: Emerging data associated subjective cognitive complaints (SCC) with a heightened risk of future cognitive decline in Parkinson´s Disease (PD).

Objective: To determine whether SCC may predict the development of cognitive impairment in PD patients at baseline.

Methods: Over 4 years, major aspects of motor and non-motor symptoms were assessed. SCC were evaluated by non-motor symptoms scale domain-5 (NMSS5). The predictor value of SCC in cognitive change was assessed with univariate linear regression analyses, with NMSS5 at baseline as predictor. Change in cognition (ΔMoCA) was calculated by subtracting Montreal Cognitive Assessment Scale (MoCA) scores at baseline from scores obtained at reassessment and employed as the outcome. We replicated these analyses by employing alterations in MoCA subdomains as outcomes.

Results: 134 patients were evaluated at baseline, of those 73 PD patients were reassessed four years later. In our study, SCC didn´t act as a predictor for future cognitive decline. However, baseline NMSS5 was associated significantly with variation in attention, naming, and orientation domains.

Conclusion: Our findings did not support that SCC in PD patients acts as a predictor of global cognitive decline. However, our findings enhance comprehension of how SCC correlates with performance in distinct cognitive areas, thereby providing better guidance for patients on their current complaints.