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Dysphagia in Parkinson Disease: Part I – Pathophysiology and Diagnostic Practices

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Denis Michael Rudisch at University of Wisconsin–Madison
Denis Michael Rudisch
Maryann N. Krasko at University of Wisconsin–Madison
Maryann N. Krasko
Ryan Burdick at University of Wisconsin–Madison
Ryan Burdick
Courtney Broadfoot at University of Wisconsin–Madison
Courtney Broadfoot
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Purpose of Review Dysphagia affects the majority of individuals with Parkinson disease (PD) and is not typically diagnosed until later in disease progression. This review will cover the current understanding of PD pathophysiology, and provides an overview of dysphagia in PD including diagnostic practices, gaps in knowledge, and future directions. Recent Findings Many non-motor and other motor signs of PD appear in the prodrome prior to the manifestation of hallmark signs and diagnosis. While dysphagia often presents already in the prodrome, it is not routinely addressed in standard neurology examinations. Summary Dysphagia in PD can result in compromised efficiency and safety of swallowing, which significantly contributes to malnutrition and dehydration, decrease quality of life, and increase mortality. The heterogeneous clinical presentation of PD complicates diagnostic procedures which often leads to delayed treatment. Research has advanced our knowledge of mechanisms underlying PD, but dysphagia is still largely understudied, especially in the prodromal stage.
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Vol:.(1234567890)
Current Physical Medicine and Rehabilitation Reports (2023) 11:176–187
https://doi.org/10.1007/s40141-023-00392-9
1 3
Dysphagia inParkinson Disease: Part I – Pathophysiology
andDiagnostic Practices
DenisMichaelRudisch1,2 · MaryannN.Krasko1,2 · RyanBurdick3,4 · CourtneyK.Broadfoot3,4 ·
NicoleRogus‑Pulia3,4 · MichelleR.Ciucci1,2,5
Accepted: 6 March 2023 / Published online: 28 March 2023
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023
Abstract
Purpose of Review Dysphagia affects the majority of individuals with Parkinson disease (PD) and is not typically diagnosed
until later in disease progression. This review will cover the current understanding of PD pathophysiology, and provides an
overview of dysphagia in PD including diagnostic practices, gaps in knowledge, and future directions.
Recent Findings Many non-motor and other motor signs of PD appear in the prodrome prior to the manifestation of hall-
mark signs and diagnosis. While dysphagia often presents already in the prodrome, it is not routinely addressed in standard
neurology examinations.
Summary Dysphagia in PD can result in compromised efficiency and safety of swallowing, which significantly contributes
to malnutrition and dehydration, decrease quality of life, and increase mortality. The heterogeneous clinical presentation
of PD complicates diagnostic procedures which often leads to delayed treatment. Research has advanced our knowledge of
mechanisms underlying PD, but dysphagia is still largely understudied, especially in the prodromal stage.
Keywords Parkinson disease· Swallowing· Dysphagia· Pathophysiology· Diagnosis· Saliva· Non-motor· Motor
Introduction
Parkinson disease (PD) is a progressive, degenerative,
multi-system disorder. Signs of disease include the tradi-
tional hallmark motor signs – bradykinesia, resting tremor,
rigidity, and postural instability – as well as multiple non-
motor and ‘other’ motor signs such as orthostatic hypoten-
sion, cardiac dysautonomia, gastrointestinal dysmotility, and
deficits in higher order functions such as communication,
cognition, and affect [1]. Impaired swallowing, or dysphagia,
is a significant concern in PD, as functional swallowing is
controlled by multiple somatic and autonomic sensorimotor
Denis Michael Rudisch and Maryann N. Krasko co-first authors.
* Denis Michael Rudisch
rudisch@surgery.wisc.edu
Maryann N. Krasko
krasko@surgery.wisc.edu
Ryan Burdick
rjburdick@wisc.edu
Courtney K. Broadfoot
cbroadfoot@medicine.wisc.edu
Nicole Rogus-Pulia
npulia@wisc.edu
Michelle R. Ciucci
ciucci@surgery.wisc.edu
1 Department ofSurgery, Division ofOtolaryngology—Head
& Neck Surgery, University ofWisconsin-Madison, 1300
University Ave, Madison, WI53706, USA
2 Department ofCommunication Sciences andDisorders,
University ofWisconsin-Madison, 1975 Willow Drive,
Madison, WI53706, USA
3 Department ofMedicine, Division ofGeriatrics
andGerontology, School ofMedicine andPublic Health,
University ofWisconsin-Madison, 1685 Highland Avenue,
Madison, WI53705, USA
4 Geriatric Research Education andClinical Center, William
S. Middleton Memorial Veterans Hospital, 2500 Overlook
Terrace, Madison, WI53705, USA
5 Neuroscience Training Program, University
ofWisconsin-Madison, 1111 Highland Ave, Madison,
WI53705, USA
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