Biomarkers in Neural Disorders
Biomarkers in Neural Disorders
This study seeks to establish the sensitivity and specificity of what appears to be a unique
 brainstem biomarker of Parkinson's Disease (PD) - an electrically induced olygosynaptic
 nasotrigeminal reflex response - in differentiating early stage PD from normal controls and
 from patients with various other neurodegenerative diseases. This study will additionally
 compare the biomarker to olfactory testing.
Parkinson's disease (PD), a devastating age-related disease that is clinically defined by its
 effects on the motor system, afflicts more than six million people worldwide, imposing
 enormous burdens on patients, relatives, caretakers, and society in general. Diagnostic
 errors are common, particularly as symptoms first arise. The most common misdiagnoses are
 Alzheimer's disease (AD), essential tremor, and vascular pseudo-Parkinson's Disease. An
 accurate diagnosis is typically made at a later stage of the disease when marked and
 irreversible damage has occurred within the motor control system of the brain. Sensitive and
 specific biomarkers of the early stages of PD are urgently needed. Identification of such
 markers is critical for the development and assessment of medications and other interventions
 designed to eliminate or reduce the gradual and irreversible decline of neurons involved in
 the disorder. This study seeks to establish the sensitivity and specificity of what appears
 to be a unique brainstem biomarker of PD - an electrically induced trigeminal nerve blink
 reflex response - in differentiation of early stage PD from normal controls and such
 neurodegenerative diseases as early stage AD, progressive supranuclear palsy (PSP), and
 diffuse Lewy Body disease (DLBD). This study will additionally compare the biomarker to
 olfactory test results.
Inclusion Criteria:

 -  The Parkinson's disease (PD) patients will be Hoehn and Yahr stage 2 or less with a
 history of motor symptoms less than two years.

 -  The Alzheimer's disease (AD) patients will meet the 2011 National Institute on
 Aging-Alzheimer's Association and the 1984 National Institute for Neurological and
 Communicative Disorders and Stroke-Alzheimer's disease and Related Disorders
 Association criteria for probable AD.

 -  The progressive supranuclear palsy (PSP) patients will have met the NINDS-SPSP
 criteria for probable PSP, which requires vertical supranuclear gaze palsy, prominent
 postural instability, and falls in the first year of onset, as well as a number of
 other clinical features.

 -  The DLBD patients will meet the Consensus Criteria for the clinical diagnosis of DLBD.

 -  The healthy controls will be matched to the PD patients on such variables as sex, age,
 education level, and ethnicity.

 -  The essential tremor (ET), multiple system atrophy (MSA), myasthenia gravis (MG),
 multiple system atrophy (MSA), Parkinson's disease dementia (D-PD), and Spinal Cord
 Injury (SCI) patients will meet the generally-accepted diagnostic criteria for these
 disorders.

 Exclusion Criteria:

 -  Drug abuse.

 -  Any other known and potentially confounding condition that could reasonably be
 expected to interfere with the study assessments.

 -  Under age 18.

 -  Over age 80.

 -  Smoker.

 -  Pregnant or nursing.

 -  Healthy control with a first degree relative who has a neurodegenerative disease.