The perception of apathy by caregivers of patients with dementia in Parkinson's disease

Background Apathy is one of the main neuropsychiatric symptoms in patients with Parkinson's disease (PD) and is associated with Parkinson's disease dementia (PDD). Objective To identify the characteristics of apathy in individuals with PDD according to caregiver perception. Methods Thirty-nine patients with PD according to MDS criteria for PDD were included. The following scales were used: the Hoehn and Yahr, the Unified Parkinson's Disease Rating Scale III, Scales for Outcomes in Parkinson's Disease-Cognition (SCOPA Cog), the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Apathy Evaluation Scale (AES). Results A total of 97.4% of the patients showed results consistent with apathy. Analysis of question 14 of the AES revealed no correlation with the total result of all the questions [r=-1293, r2=0.0167, 95%CI (-0.4274 to 0.1940), P=0.2162], however, there was a correlation of responses to the same question with depression data on the MADRS scale [r=-0.5213, r2=0.2718, 95%CI (-0.7186 to -0.2464), P=0.00033]. Conclusion Apathy is a disorder associated with PDD. However, the scoring scheme of the AES questions can lead to different interpretations of caregiver responses, highlighting limitations of the tool for use in studies of PDD.