Objective/Rationale:
Parkinson’s disease (PD) dementia is often preceded by a phase of mild cognitive impairment (PD-MCI), for which diagnostic criteria have been recently proposed. However, there remains much that is unknown regarding what causes PD-MCI and PD dementia, why patients exhibit different profiles of cognitive symptoms or functional impairment, which patients are most likely to convert from normal cognition to PD-MCI or PD dementia, or whether all PD-MCI patients go on to develop dementia. The goal of our project is to determine the clinical and neuroimaging biomarkers that predict cognitive decline in PD over time.
Project Description:
In this project, a cohort of approximately 75 non-demented PD patients will be followed prospectively with brain magnetic resonance imaging (MRI) scans and annual clinical and neuropsychological evaluations over a three-year period. The cohort includes a well-characterized group of PD patients who have normal cognition or PD-MCI and who previously have had comprehensive baseline clinical, neuropsychological, neuroimaging and biospecimen assessments. These patients will now undergo longitudinal evaluations with detailed testing of clinical, cognitive, behavioral, motor and functional abilities. With state-of-the-art neuroimaging techniques and thorough, longitudinal assessments, we will identify predictors of cognitive decline (or stability) and determine whether different clinical and neuroimaging profiles of PD-MCI influence its progression.
Relevance to Diagnosis/Treatment of Parkinson’s Disease:
The results of this study will advance our understanding of PD cognitive impairment and clinical and neuroimaging markers associated with cognitive decline. These findings will enable clinicians to better diagnose cognitive impairment in PD patients and provide clearer prognoses regarding progression of cognitive deficits to patients and their families. In addition, these findings will enable researchers to better develop therapeutic trials that select the most appropriate patients for the testing of interventions that may halt or slow down cognitive decline or target specific cognitive deficits.
Anticipated Outcome:
We anticipate that certain clinical and neuroimaging profiles are associated with greater risk for conversion to PD-MCI or PD dementia, while others confer a greater likelihood of cognitive stability. We will gain a better understanding of baseline predictors of cognitive decline, differences in PD-MCI subtypes and progression, and annual rates of change in clinical, cognitive and functional abilities.