Participant and Study Partner Reported Impact of Cognition on Functional Activities in Parkinson's Disease

Original research: longitudinal evaluation of cognitively demanding daily function using performance-based functional assessment highlights heterogeneous trajectories in cognitive and functional abilities in people with Parkinson's disease

Background

Longitudinal assessment of functional abilities in Parkinson's disease (PD) is needed to determine the efficacy of cognitive interventions in providing meaningful improvements in daily life. Additionally, subtle changes in instrumental activities of daily living may precede a clinical diagnosis of dementia and could aid earlier detection of and intervention for cognitive decline.

Objective

The primary goal was to validate the longitudinal application of the University of California San Diego Performance-Based Skills Assessment (UPSA). An exploratory secondary goal was to determine whether UPSA may identify individuals at higher risk of cognitive decline in PD.

Methods

Seventy participants with PD completed the UPSA with at least one follow-up visit. Linear mixed effects modeling was used to identify associations between baseline UPSA score and cognitive composite score (CCS) over time. Descriptive analysis of four heterogeneous cognitive and functional trajectory groups and individual case examples was performed.

Results

Baseline UPSA score predicted CCS at each timepoint for functionally impaired and unimpaired groups (p < 0.01) but did not predict the rate change in CCS over time (p = 0.83). Participants displayed heterogenous trajectories in both UPSA and CCS during the follow-up period. Most participants maintained both cognitive and functional performance (n = 54), though some displayed cognitive and functional decline (n = 4), cognitive decline with functional maintenance (n = 4), and functional decline with cognitive maintenance (n = 8).

Conclusion

The UPSA is a valid measure of cognitive functional abilities over time in PD. Given the heterogeneity of functional and cognitive trajectories, this performance-based assessment did not predict cognitive decline with this relatively short follow-up. Further work is needed to understand longitudinal functional assessments in PD-associated cognitive impairment.

Cognitive Impairment in Neurodegenerative Movement Disorders

Patients with neurodegenerative movement disorders can develop cognitive impairment during the disease. Cognitive symptoms have been associated with decreased quality of life, higher caregiver burden, and earlier institutionalization, and are therefore critical for physicians to understand and address. The evaluation of cognitive performance of patients with neurodegenerative movement disorders is important for providing adequate diagnosis, management, prognosis, and support patients and their caregivers. In this review, we discuss the features of the cognitive impairment profile of commonly encountered movement disorders: Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy, corticobasal syndrome, and Huntington's disease. In addition, we provide neurologists with practical guidance and evaluation tools for the assessment and management of these challenging patients.

Cognitive-Driven Activities of Daily Living Impairment as a Predictor for Dementia in Parkinson Disease: A Longitudinal Cohort Study

BACKGROUND AND OBJECTIVES

One-third of Parkinson disease (PD) patients with PD-mild cognitive impairment (PD-MCI) convert to dementia within a few years. Markers with a high prognostic value for dementia conversion are needed. Loss of everyday function primarily caused by cognitive dysfunction is the core criterion for the diagnosis of PD dementia, with an onset of more complex instrumental activities of daily living (IADL) dysfunction in the prodromal stage. This study evaluated the phenotype associated with cognitive IADL impairment and its predictive value for defining a high-risk group for PD dementia.

METHODS

An observational longitudinal study using cognitive and clinical scores in addition to genetic and CSF biomarkers was conducted. The Functional Activities Questionnaire quotient (cut-off ≥1), indicating more cognitive than motor-driven IADL impairment, defined cognitive IADL impairment status at baseline. Hazard ratios (HRs) were used to compare the impact of baseline classifications on dementia conversion.

RESULTS

Of 268 patients with PD assessed at baseline, 108 (40.3%) had PD-MCI. After a period of 3.78 ± 0.84 years, 164 (61.2%) patients were reassessed. At follow-up, 93 (56.7%) patients had no cognitive impairment, 54 (32.9%) fulfilled PD-MCI criteria, and 17 (10.4%) had developed dementia. The HR of baseline cognitive IADL impairment (n = 37) for dementia conversion was descriptively higher than for PD-MCI, but highest in patients with both markers (HR = 12.01, 95% CI 4.47-32.22, p < 0.001). In the follow-up sample, nearly half of the patients (n = 10, 47.6%) with baseline classification of cognitive IADL impairment and PD-MCI converted to dementia. Baseline status of cognitive IADL impairment was associated with higher nonmotor burden, worse cognitive performance, and more severe IADL progression over the study period.

DISCUSSION

The importance of differentiating between cognitive and motor aspects on ADL function in PD and monitoring cognitive ADL impairment in the prodromal stage of dementia is paramount. Patients with PD-MCI and cognitive IADL impairment may be a valuable target group for clinical trials aiming to slow down the development of dementia.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov NCT03687203.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that impairment of cognitive activities of daily living is associated with progression from MCI to dementia among patients with Parkinson disease.

A Comparison of Functional Abilities in Individuals with Mild Cognitive Impairment and Parkinson's Disease with Mild Cognitive Impairment Using Multiple Assessment Methods

OBJECTIVE

This study used multiple assessment methods to examine instrumental activities of daily living (IADLs) performance in individuals with Parkinson's disease with mild cognitive impairment (PD-MCI) compared to individuals with mild cognitive impairment (MCI) and cognitively healthy older adults (HOA). Associations between functional performance and cognition were also examined.

METHODS

Eighteen individuals with PD-MCI, 48 individuals with MCI, and 66 HOAs were assessed with multiple IADL measures, including direct observation, a performance-based measure, and self- and informant-report questionnaires. Performance on the direct-observation measure was further characterized by coding for four error types: omissions, substitutions, and inefficient and irrelevant/off-task actions.

RESULTS

Both the PD-MCI and MCI groups performed more poorly on the overall score for all IADL measures relative to HOAs. Although the PD-MCI and MCI groups did not differ in overall performance, on the direct-observation measure, the PD-MCI group took longer and made more inefficient and irrelevant/off-task errors relative to the HOA and MCI groups, whereas the MCI group made more omission and substitution errors relative to HOAs. Further, the pattern of cognitive correlates that associated most strongly with the functional measures varied across groups and functional assessment methods.

CONCLUSION

Compared to HOAs, PD-MCI and MCI groups demonstrated increased difficulties performing everyday activities, and cognitive and motor abilities differentially contributed to the everyday task difficulties of these two groups.

The Instrumental Activities of Daily Living in Parkinson’s Disease Patients Treated by Subthalamic Deep Brain Stimulation

Background

Everyday functioning and instrumental activities of daily living (IADL) play a vital role in preserving the quality of life in patients with Parkinson’s disease (PD) after deep brain stimulation of the subthalamic nucleus (STN-DBS).

Objective

The main goal of the current study was to examine IADL change in pre-and post-surgery of the STN-DBS. We also analyzed the influence of the levodopa equivalent daily dose (LEDD) and global cognitive performance (Dementia Rating Scale; DRS-2) as covariates in relation to IADL.

Methods

Thirty-two non-demented PD patients were administered before and after STN-DBS neurosurgery the Penn Parkinson’s Daily Activities Questionnaire (PDAQ; self-report), the DRS-2 and Beck Depression Inventory (BDI-II) to assess IADL change, global cognition, and depression.

Results

We found a positive effect of STN-DBS on IADL in the post-surgery phase. Moreover, lower global cognition and lower LEDD are predictive of lower IADL in both pre-surgery and post-surgery examinations.

Summary/Conclusion

STN-DBS in PD is a safe method for improvement of everyday functioning and IADL. In the post-surgery phase, we show a relation of IADL to the severity of cognitive impairment in PD and to LEDD.

Divergence Between Informant and Self-Ratings of Activities of Daily Living Impairments in Parkinson’s Disease

Objective

To examine the agreement between self- and informant-reported activities of daily living (ADL) deficits in Parkinson’s Disease (PD) patients, and to examine factors influencing ADL ratings.

Background

In PD, the loss of functional independence is an important outcome of disease progression. The valid assessment of ADL function in PD is essential, but it is unclear to what extent informants’ and patients’ perceptions of their daily functions concur, and how other factors may influence both ratings.

Methods

Data of 150 PD patients who underwent cognitive and motor testing, as well as their informants were analyzed. The 10-item Functional Activities Questionnaire (FAQ), completed separately by patients (FAQ-S) and their informants (FAQ-I), assessed ADL function. Weighted κ statistics summarized level of agreement, and a discrepancy score (FAQ-I – FAQ-S) quantified agreement. Correlation analyses between FAQ total scores, patient and informant characteristics, and cognitive scores were conducted, with post hoc regressions to determine the associations between both FAQ scores and cognition, independent of patient characteristics.

Results

The sample included 87 patients with normal cognition, 50 with mild cognitive impairment, and 13 with dementia. Overall, there was fair to moderate agreement between patients and informants on individual FAQ items (0.27 ≤ κ ≤ 0.61, p &lt; 0.004), with greater discrepancies with increasing cognitive impairment. Patients’ age, motor severity, non-motor burden, and depression also affected both ratings (0.27 ≤ r ≤ 0.50, p &lt; 0.001), with motor severity showing the greatest influence on both ratings. Both the FAQ-I and FAQ-S were correlated with almost all cognitive domains. Post hoc regression analyses controlling for patient characteristics showed that the attention domain was a significant predictor of both the FAQ-S and FAQ-I scores, and memory was also a significant predictor of the FAQ-I score. Only 29.3% of patients agreed perfectly with informants on the FAQ total score, with informants most commonly rating ADL impairments as more severe than patients.

Conclusions

Patient and informant ratings of ADL function using FAQ items showed moderate agreement, with only few items reaching substantial agreement. Ratings of both were associated with patient cognitive status, but also other characteristics. In addition to patient and informant reports, objective measures are needed to accurately classify ADL deficits in PD.

Subjective Cognition Reported by Caregivers Is Correlated With Objective Cognition in Liver Transplant Recipients

Objective cognitive assessments, a gold standard diagnostic tool for cognitive impairment, may not be feasible in busy liver transplantation (LT) practice because they are often time consuming. This study determined whether subjective cognition, patients' self-ratings and/or caregivers' ratings of patients' cognition, reflects objective cognition in LT recipients. A convenience sample of 60 adult LT recipients and their caregivers, recruited at a single transplant center, participated in this cross-sectional descriptive study. Subjective cognition (ie, recipient self-rated and caregiver rated) was measured using the Everyday Cognition (ECog; global and 6 domain scores). Objective global and domain-specific cognition of recipients was measured using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Trail Making Test parts A and B, Digit Span Backward, and Rey-Osterrieth Complex Figure. Agreement between LT recipients' ECog scores and those of their caregivers was fair to moderate (intraclass correlation coefficient = 0.48 for global score, 0.35-0.56 for domain scores). Significant, albeit rather weak, correlations were found between subjective and objective scores. Recipients' ECog visuospatial abilities scores were correlated with Rey-Osterrieth Complex Figure scores (r_s  = -0.39; P = 0.007), whereas caregivers' ECog global, attention, visuospatial abilities, and organization scores were, respectively, correlated with the scores of RBANS global (r_s  = -0.33; P = 0.04) and attention (r_s  = -0.46; P = 0.005), Rey-Osterrieth Complex Figure (Copy; r_s  = -0.34; P = 0.03), and Trail Making Test part A (r_s  = 0.31; P = 0.049). The findings suggest that caregivers may estimate LT recipients' cognition better than recipients themselves. Caregivers may provide supplemental information that could be useful for clinicians when considering the cognitive functioning of LT recipients.

Hippocampal correlates of episodic memory in Parkinson's disease: A systematic review of magnetic resonance imaging studies

The present review asks whether magnetic resonance imaging (MRI) studies are able to define neural correlates of episodic memory within the hippocampus in Parkinson's disease (PD). Systematic searches were performed in PubMed, Web of Science, Medline, CINAHL, and EMBASE using search terms related to structural and functional MRI (fMRI), the hippocampus, episodic memory, and PD. Risk of bias was assessed for each study using the Newtown-Ottawa Scale. Thirty-nine studies met inclusion criteria; eight fMRI, seven diffusion MRI (dMRI), and 24 structural MRI (14 exploring whole hippocampus and 10 exploring hippocampal subfields). Critical analysis of the literature revealed mixed evidence from functional and dMRI, but stronger evidence from sMRI of the hippocampus as a biomarker for episodic memory impairment in PD. Hippocampal subfield studies most often implicated CA1, CA3/4, and subiculum volume in episodic memory and cognitive decline in PD. Despite differences in imaging methodology, study design, and sample characteristics, MRI studies have helped elucidate an important neural correlate of episodic memory impairment in PD with both clinical and theoretical implications. Natural progression of this work encourages future research on hippocampal subfield function as a potential biomarker of, or therapeutic target for, episodic memory dysfunction in PD.