Different Associated Factors of Subjective Cognitive Complaints in Patients With Early- and Late-Onset Parkinson's Disease

Abstract

Background: Subjective cognitive complaints (SCCs), which are associated with a higher risk of cognitive decline, are widespread in the patients with Parkinson's disease (PD). The previous studies have reported inconsistent factors related to SCCs in the patients with late-onset PD (LOPD), and there is limited information on SCCs in the patients with early-onset PD (EOPD).Objective: We aimed to investigate the factors associated with SCCs in the drug-naïve patients with EOPD and LOPD without cognitive impairment.Methods: This cross-sectional study included 332 drug-naïve patients with PD, among whom 134 were EOPD and 198 were LOPD. Motor and non-motor symptoms, such as global objective cognitive status, depression, anxiety, apathy, fatigue, sleep, rapid eye movement sleep behavior disorder, orthostatic hypotension, and excessive daytime sleepiness, were assessed.Results: Twenty-five (18.66%) patients with EOPD and 49 (24.74%) patients with LOPD reported SCCs. A multivariate binary logistic regression analysis revealed that older age at onset [odds ratio (OR) = 1.24, P = 0.002], higher apathy score (OR = 1.13, P = 0.003), and lower scores in the visuospatial/executive abilities (OR = 0.25, P < 0.001) and memory (OR = 0.50, P = 0.024) domains of the Montreal Cognitive Assessment were associated with a higher risk of SCCs in the EOPD group. Higher apathy (OR = 1.06, P = 0.011) and anxiety (OR = 1.14, P < 0.001) scores were associated with SCCs in the LOPD group.Conclusion: Subjective cognitive complaints are only associated with mood disorders in patients with LOPD. In addition, SCCs may reflect subthreshold cognitive impairment in the patients with EOPD.

Subjective Cognitive Complaints in Cognitively Normal Patients With Parkinson’s Disease: A Systematic Review

“…Cognitive impairment in PD also affects multiple cognitive domains [ 29 - 31 ], and the term “cognitive” is recommended to indicate subjective impairment. In the selected studies of this review, the term “SCCs” was the most frequently used (10 studies) [ 32 - 41 ], and “subjective memory complaints (SMCs)” [ 42 - 46 ] and “SCD” [ 37 , 47 - 50 ] were both used in five studies each. Mills et al [ 37 ] used both “SCCs” and “SCD.” Early studies used the term “memory,” [ 43 , 44 , 46 ] which seems to be influenced by the term SMCs from the AD field.…”

“…10 Cognitive impairment in PD also affects multiple cognitive domains, [29][30][31] and the term "cognitive" is recommended to indicate subjective impairment. In the selected studies of this review, the term "SCCs" was the most frequently used (10 studies), [32][33][34][35][36][37][38][39][40][41] and "subjective memory complaints (SMCs)" [42][43][44][45][46] and "SCD" 37,47-50 were both used in five studies each. Mills et al 37 used both "SCCs" and "SCD. "…”

“…32,36,39,41 Among them, four studies assessed SCCs using part of a large scale: the Nonmotor Symptoms Questionnaire 52 Item 12 43 and the MDS-Unified PD Rating Scale (UP-DRS) 53 question 1.1. 32,36,41 Two studies used questions on patients' performance in five 47 or seven 45 cognitive domains. Ten studies assessed SCCs using questionnaires administered to patients: Non-Motor Symptoms Scale for Parkinson's Disease 54 domain 5 (two studies), 33,34 Memory Complaints Questionnaire 55 (one study), 42 Neurobehavioral Inventory (NBI) 56 (two studies), 32,35 Quality of Life in Neurological Disorders 57 -Cognition: General Concerns and Cognition: Executive Function (one study), 37 Forgetfulness Assessment Inventory 58 (one study), 46 Subjective Cognitive Decline Questionnaire (one study), 50 Cognitive Complaint Interview 59 (one study), 38 and Parkinson's Disease Cog-nitive Functional Rating Scale 60 (one study).…”

“…33 Hong et al 49 also reported lower semantic fluency in PD patients with SCCs than in non-PD individuals with SCCs. It remains unclear whether there is minimal objective cognitive decline in cognitively normal patients with SCCs; however, it is noteworthy that three 36,37,41 of four studies with large sample sizes (n > 150) 36,37,39,41 commonly reported lower memory function in participants with SCCs than in those without SCCs.…”

“…38,45 Only three studies 33,34,41 assessed apathy, but all reported a significant association between apathy and SCCs. 33,34,40,41 In addition, they related to SCCs in the same way as depression in four 33,34,38,41 out of six studies; 33,34,38,41,42,45 therefore, whether anxiety and apathy are independent of depression should be explored.…”