Clinical Implication of High Sensitivity C-Reactive Protein for the Development of Dementia in Parkinson's Disease

Abstract

Idiopathic Parkinson’s disease (PD) is characterized by various motor symptoms, including bradykinesia, rigidity, postural instability, and resting tremors. As a common neurodegenerative disorder, PD affects 1% to 2% of the general population over 65 years of age.1 In addition to major motor symptoms, a variety of non-motor symptoms appear throughout the course of PD.2 These non-motor symptoms comprise a variety of cognitive, neuropsychiatric, sleep, autonomic, and sensory disorders. Among different non-motor symptoms, cognitive disorder such as dementia is a frequent manifestation of advanced PD.3 Dementia is the most devastating nonmotor feature that causes severe decline in quality of life. It increases caregiver burden and mortality as well as institutionalization. The prevalence of dementia in PD ranges from 24% to 50%. PD dementia accounts for about 3–4% of all dementia in the population.3 Therefore, identifying biomarkers that can predict the development of PD dementia is important as they could help clinician select high-risk patients for appropriate counseling and plans for future treatment. Although the pathophysiologic mechanisms involved in the development of dementia in PD remain unknown, postmortem and in vivo studies as well as epidemiological and pre-clinical studies have suggested that neuro-inflammation may play an important role in the pathogenesis of PD, especially in the non-motor symptoms such as cognitive impairClinical Implication of High Sensitivity C-Reactive Protein for the Development of Dementia in Parkinson’s Disease