Outcome Measures for Parkinson's Disease Dementia: A Systematic Review

Abstract

Background Parkinson’s disease dementia (PDD) is a major cause of morbidity and mortality in Parkinson’s disease (PD), which severely affects patient functioning and quality of life and increases the risk for nursing home admission. Unfortunately, current treatment options for PDD are limited and have only marginal therapeutic effects. As novel treatments are developed, there will be a need to assess their efficacy in well-designed randomized controlled trials. However, there is no consensus on the optimal outcome measures for use in PDD clinical trials. Methods A systematic review of PDD clinical trials and empiric studies of outcome measures used in PDD was performed. Outcome measures were divided into five categories: 1) cognitive; 2) behavioral and mood; 3) activities of daily living and quality of life; 4) global; and 5) caregiver burden. Findings A total of 20 PDD pharmacologic clinical trials were identified. These trials incorporated a broad array of outcome measures, which were used inconsistently across trials. We summarize the psychometric properties and other relevant data on outcome measures used, including their diagnostic utility, inter-rater reliability, test-retest reliability, responsiveness, clinically meaningful change, and availability of alternate forms. Conclusions We have identified the best-evidenced PDD outcome measures in each domain. Further research is needed to assess the validity, reliability, and clinically meaningful change of these measures in PDD to inform the design of future clinical trials and enhance the ability of clinicians, researchers and policy-makers to interpret study results. In addition, the development of outcome measures specific to PDD may be warranted.

Validation of a performance‐based assessment of cognitive functional ability in Parkinson's disease

“…Spearman correlations were considered if graphical checks found evidence of major nonlinearity in the relationships. DRS‐2 was chosen as the primary cognitive measure for comparison with UPSA because it is a well‐validated and recommended measure of global cognition in PD . Likewise, UPDRS Part III score is the most commonly used and reliable measure of motor severity in PD .…”

“…Dementia in PD (PDD) results in poorer quality of life, increased morbidity and mortality, caregiver burnout, and nursing home placement . Effective treatments for cognitive impairment in PD are urgently needed; yet, reliable methods to evaluate the efficacy of new treatments must first be better established . To date, clinical trials for pharmaceutical agents targeting PDD have utilized cognitive scales as primary outcome measures, namely the Mini‐Mental State Examination or the cognitive subscale of the Alzheimer's Disease Assessment Scale .…”

Overview of reviews of standardised occupation‐based instruments for use in occupational therapy practice

“…Meanwhile, 25 systematic reviews ( Wales, Clemson, Lannin & Cameron, 2016) used standardised quality checklists such as the COS-MIN and Terwee's Checklist to evaluate the quality of the psychometric reporting. Fifteen reviews (Bartula & Sherman, 2013;de Baets et al, 2017;Gouttebarge, Wind, Kuijer & Frings-Dresen, 2004;Harvey, Robin, Morris, Graham & Baker, 2008;Holden, Jones, Baker, Boersma & Kluger, 2016;Innes, 2006;Innes & Straker, 1999a,b;Lewandowski, Toliver-Sokol & Palermo, 2011;Lotzin et al, 2015;Monod et al, 2011;Peer & Tenhula, 2010;Swinkels, Dijkstra & Bouter, 2005;Tse, Douglas, Lentin & Carey, 2013;Williams et al, 2007) used a non-standardised checklist (i.e. researcher-developed or adapted), and the remaining 18 just descriptively reported the psychometric evidence gathered.…”

Aligning physiology with psychology: Translational neuroscience in neuropsychiatric drug discovery

“…These behavioural abnormalities compound the pain and suffering of the affected, and determine the outcome of therapy. For example, Parkinson's is commonly associated with co-morbid depression, anxiety, and apathy, as well as cognitive psychosis (Cooney and Stacy, 2016;Holden et al, 2016). Neuropsychiatric symptoms are common in Alzheimer's disease (Spalletta et al, 2010), and treated pharmacologically with variable results (Wang et al, 2015a).…”