CLINICAL BIOMARKERS IN PARKINSON’S DISEASE AND ATYPICAL PARKINSONISM

Abstract

The use of clinical biomarkers in the differential diagnosis and prognosis of parkinsonian syndromes remains
valuable, despite the progress made in the identification of laboratory, imaging and genetic markers. The
present review includes a reference on Movement Disorders Society criteria for prodromal Parkinson’s
disease (PD) which were designed to estimate the probability of prodromal PD in individuals with any or
very mild motor symptoms. The prognostic value of individual biomarkers for idiopathic PD is also discussed,
such as age of onset and motor subtype, as well as the role of REM sleep behavior disorder, hyposmia,
oculomotor disorders, postural hypotension, oropharyngeal dysfunction and various neuropsychiatric
manifestations in the differential diagnosis among parkinsonian syndromes. Regarding REM sleep behavior
disorder, in addition to its high prognostic value as a state of an emerging α-synucleinopathy, its use in the
classification of patients according to the recently proposed brain first and body first model for idiopathic
PD is also important. The use of this model holds useful pathophysiological and prognostic implications
which are also summarized in this review. Finally, key parameters that guide the therapeutic strategy in
idiopathic PD are highlighted, such as patients’ age and lifestyle and possible comorbidities.