Idiopathic Parkinson's Disease (PD) is a neurological degenerative condition that with time affects our most critical systems. It is the second most common degenerative disease in the United States, after Alzheimer’s, and there are 60,000 new cases every year. The four cardinal motor symptoms are tremor, often a resting tremor, rigidity, or stiff movement, akinesia or dyskinesia, meaning lack of or slow movement, and postural changes that result in stooping. It is thought that these motor changes, coupled with denervated and atrophied muscle fibers in the pharynx, can make it difficult to use muscles to their fullest capacity and affect speech, swallowing, and voice. The exact cause of dysphagia and dysarthria in PD is unknown, but is suspected to be multiple combined factors.
As speech-language pathologists, our clients often report noticing symptoms years prior to diagnosis. This is because there isn’t yet a standardized approach to diagnosing Parkinson's prior to the depletion of dopamine in the substantia nigra. The symptoms are often related to gastrointestinal health and smell, or voice and swallowing. One theory for this suggests that one phenotype of PD can begin in the peripheral nervous system (PNS). Eventually, both PNS and CNS are effected as the disease progresses. During post mortem studies, Braak et. al found changes in the brainstem prior to overt dopaminergic loss, which explains why PWPD often complain of mood changes, loss of smell, and constipation long before motor decline. Researchers can track these brain changes with the presence of Lewy neurites and Lewy bodies. As the disease progresses, striatal dopaminergic neurons are lost, and this is when the majority of PWPD seek out a diagnosis, due to the resulting motor changes. By this time, dopamine could be reduced by 80-90%. Eventually, the disease reaches the limbic system and neocortex and this is when we see issues with sleep, motivation, delirium, and cognition. When SLPs know that eventually most areas of the brain are impacted we can better support our clients.
Although there are similarities in pathology, PWPD are a heterogeneous group, therefore it is important to assess and treat each client comprehensively and track their unique symptoms. Parkinsonism can be caused by brain injury, drug use, genetics, and unknown causes. There are multiple factors that dictate how the disease will progress, including gender, general health, and age. For instance, men are 1.5 times more likely to acquire it and those diagnosed younger tend to have a slower progression. Because the majority of PWPD develop swallowing, cognitive, and communication difficulties, it is our job as pathologists to continually assess each therapy domain. Follow-ups and reassessments are key to maintaining gains made in treatment and also developing skills prior to a significant loss of function.
Every assessment includes an interview to learn about history, current living conditions, major complaints, concomitant disorders, strengths, and goals. Include family and caregivers as they are also experiencing life changes. They are usually good historians and can speak to signs that the PWPD may not have an awareness of. Their sensorimotor decline can contribute to a lack of awareness of deficits. For example, when it comes to dysphagia, as little as 15% of people complain of symptoms, and when tested objectively up to 85% have dysphagia.
Patient perception questionnaires help us to measure outcomes from the client’s perspective. They are a way to not only gain information about how your clients are feeling and experiencing aspects of their disease, but also to track progress. We can use them to make therapy functional, and in-turn improve motivation and adherence. When the client is center in decision making, we can write meaningful goals.
Examples of patient perception measures for PD:
Voice-
Voice Handicap Index
Voice QOL
Communication Participation Index Bank
Swallow-
EAT-10
Sydney Swallow Questionnaire
Cognition-
Functional Activities Questionnaire
The Penn Parkinson's Daily Activities Questionnaire-15
Executive Skills Questionnaire
Multifactorial Memory Questionnaire
Articulation-
The Communication Effectiveness Index (CETI)
Dysarthria Impact Profile (DIP)
CPIB
We take objective data in order to gather enough information to make informed decisions about our client’s physiological and anatomical functioning. If we cannot determine functioning ourselves, we then refer for imaging. The following outlines the evidence-based data to take in each domain.
For voice assessment, we can take acoustic data, tracking physiological range, max dB in different contexts, conversational Hz range, for prosody, maximum phonation time, s/z ratio screener, cepstral peak prominence, and habitual pitch. We can describe their perceptual voice quality and take aerodynamic measures. Even if you follow a protocol, for instance Lee Silverman Voice Treatment (LSVT) or SPEAK OUT!, you can add your own objective measures. Use the CAPE-V or GRBAS to help describe their voice with severity levels. This is especially helpful if you bill insurance and need measurements. These perceptual scores are typically quite subjective, however, are a useful tool to track change as long as the same user is scoring.
Focus on your clients’ needs. If they present with severe hypokinetic dysarthria and monotonous intonation, it could be helpful to track conversational pitch range. If they can no longer sing in choir, you can focus your reassessments on their overall pitch range and vocal dB while singing. PRAAT is a free software created to take acoustic data and many people offer free tutorials on how to use it. If a client presents with voice symptoms that do not seem aligned with hypokinetic dysarthria, they see no progress with therapy, or have concerning vocal quality, refer for a stroboscopy if possible. If this is not available to you, refer to an ENT for laryngoscopy.
Common signs and symptoms of voice are roughness or gravel, breathiness, asthenia, low intensity, tremor, aphonia, vocal fatigue, voice worse at the end of the day, asked to repeat, monotonous, hypernasality, and higher frequency in some people. Common imaging findings are vocal cord bowing (up to 87% of pts), vocal cord atrophy, incomplete glottal closure, reduced abduction on phonation, abnormal amplitude and mucosal waveform, tremor, vocal cord rigidity, hypertrophy of ventricular folds, and velopharyngeal insufficiency.
For swallow assessment, an oral motor exam is helpful to gain an idea of sensory and motor responses and functioning. The Mann Assessment Swallowing Ability (MASA) is a useful tool that outlines a swallow assessment, reviewing areas from ability to attend to cough response. It also offers a way to track observational change. Food and drink trials can assist in getting an idea of how the client is able to swallow, especially in the preparatory phase. Of course, imaging from a videoflouroscopy swallow study (VFSS) or fiberoptic endoscopic evaluation of swallowing (FEES) is necessary for diagnosing dysphagia and informing therapeutic approaches, texture modification, and compensations. As patients often experience esophageal disorders, it is important to refer to a gastroenterologist.
Common signs and symptoms of dysphagia are sailorrhea (excess saliva), coughing, tongue pumping, decreased mastication coordination and speed, oropharyngeal residue, increased number of swallows to clear the pharynx, reduced and slowed hyolaryngeal motion, reduced pharyngeal wall and tongue base contractions, penetration/aspiration in 25-50%, delayed pharyngeal swallow trigger, silent aspiration in 15% with no dysphagia complaints, decreased UES relaxation, esophageal dysmotility, and reflux. In addition, patients often complain of embarrassment at mealtime, prolonged meals, fear of choking, difficulty with self-feeding d/t dyskinesia, and they avoid social eating, which promotes isolation and decreased quality of life.
With cognitive assessment, there are many tests to choose from, you will essentially be symptom focused. What is it they are experiencing? Many cognitive tests like The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) tests a range of domains. You can incorporate subtests from the Boston Diagnostic Aphasia Examination (BDAE) if there are language concerns. If fatigue is an issue, you can use the Cognitive Linguistic Quick Test (CLQT+). Most SLPs are limited to what cognitive tests they have access to and hopefully you are able to complete a comprehensive evaluation based on the cognitive changes taking place. If cognition is not a primary complaint, it can be beneficial to complete a cognitive-linguistic screener, like the MOCA, SLUMS, or MMSE in order to monitor their performance through time.
Common cognitive and language findings are bradyphrenia, or slow processing speed, and changes in memory, including visual and auditory, attention, executive functioning, language, processing and comprehension of complex language, us of meaningful content, utterance length, and use of action verbs.
Lastly, when assessing speech, the oral motor exam is also relevant. DDK rates give us a way to measure articulation coordination and speed, and The Frenchay Dysarthria Assessment (FDA-2) and Assessment of Intelligibility of Dysarthric Speech (AIDS) are two common standardized dysarthria tests. SLPs can score the rate of speech, which is very relevant to PD, as PWPD often have slow and slurred speech or rapid utterances. We can also assess precision of vowels and consonants, and intelligibility level. Some SLPs use conversational analysis in order to examine areas of need in conversation, for instance measuring pauses, turn-taking, and repair ability.
Common findings of dysarthria include slow or fast rate (festinations), slurring, imprecise consonants/vowels, dysfluency, pausing, decreased self-correction, and decreasing speech intelligibility.
Auxiliary areas to follow are respiration and hearing, as these contribute greatly to communication and swallowing. A decline in respiratory function is present in 28-85% of patients. We see decreased vital capacity, increased speech inspiration time, and faster tidal breathing rate. Patients use more abdominal breathing during speech, fewer words per breath, and longer pauses. PWPD can also have higher rates of hearing loss compared to matched controls.
PWPD are a joy to work with. Due to the nature of their condition, we often get to know them well as we follow them throughout their disease progression. They also present a good challenge for us, because of their heterogeneity and changing status, it keeps us on our toes. If you are interested in working with PWPD, I recommend completing LSVT and/or SPEAK OUT!, keeping up with current dysphagia and cognition therapy practices, learning about expiratory muscle strength training (EMST), and alternative and augmentative communication (AAC). To learn more assessment and learn treatment approaches for Parkinson’s, go to speechtherapypd.com to complete the training “Parkinson’s and Speech Therapy”.
https://www.eugenespeechtherapy.com/
