Cognitive complaint in early Parkinson's disease: A pilot study
Among the diagnostic criteria for MCI due to PD, subjective cognitive complaint (SCC) reported either by the patient or the informant is required. SCC may represent the earliest stage of cognitive decline and be a risk factor for developing MCI or dementia. Prevalence of SCC in non‐demented PD patients is estimated between 5.0% and 58.7%.4 One problem is that different methods were used to evaluate SCC in these studies, as there are few validated diagnostic tool for assessing SCC in PD. From what we know, just one scale has proven good internal consistency and reliability.10
In addition, most of these studies asked patients about subjective memory complaints only. Whereas a range of cognitive domains is impaired in MCI due to PD, such as attention, executive, visuospatial, memory, and language abilities, the latter being usually less affected.11 Therefore, SCC in PD requires assessing all these domains.1
The aim of this study was to develop a measure specifically designed to identify SCC in patients with PD. The aims of this study were (i) to describe the development of the SCC measure, (ii) to assess SCC in early patients with PD using this SCC measure vs age‐matched controls, and (iii) to investigate its reproducibility and its relationship with performances in neuropsychological testing.