Managing Dysphagia in Parkinson's Disease: Early Detection, Assessment, and Interdisciplinary Care
Parkinson’s disease (PD) is a progressive neurodegenerative disorder that results in both motor and non-motor dysfunction with hypothesized multifactorial causes including exposure to neurotoxic agents such as pesticides and herbicides, proximity to industrial plants, genetic factors, oxidation and generation of free radicals, lifestyle factors such as physical activity and alcohol consumption, among others (Ben-Shlomo et al., 2024; Cosentino et al., 2021; Zafar & Yaddanapudi, 2023). PD is a basal ganglia disorder which is correlated with the accumulation of alpha-synuclein in the brain resulting in the loss of dopaminergic neurons in the substantia nigra, in turn, impacting muscle tone and movement (Zafar & Yaddanapudi, 2023).
The prevalence of PD increases with age with current literature indicating that 1% of the population is affects above the age of 60 (Zafar & Yaddanapudi, 2023). PD can result in a variety of symptoms including bradykinesia, resting tremor, rigidity, loss of smell, sleep dysfunction, excess saliva, constipation, mood disorders, dysphagia, excessive limb movements in sleep, among others (Cosentino et al., 2021; Varadi, 2020; Zafar & Yaddanapudi, 2023).
The evaluation of PD often begins with the patient’s history and physical examination and may include the quantification of the person’s cognition, mood, activities of daily living, tremors, motor examination and complications of therapy, with an essential aspect of the evaluation excluding the effects of medications that can lead to extrapyramidal side effects and motor manifestations that are indistinguishable from PD as well as other neurodegenerative conditions (Zafar & Yaddanapudi, 2023). MRI can be beneficial in differential diagnosis, use of a DAT scan for the identification of the loss of dopaminergic uptake, and the individual’s response to Levodopa treatment (Bhattacharjee et al., 2019; Zafar & Yaddanapudi, 2023). Treatment for PD may include pharmacologic interventions such as levodopa and medications aimed at symptoms control, structured physical therapy aimed at PD, speech pathology services for communication and swallowing changes, and deep brain stimulation, among other options (Biundo et al., 2017; Rogers et al., 2017; Zafar & Yaddanapudi, 2023).
Dysphagia is common for individuals with PD with studies estimating prevalence between 40-80%, is associated with several characteristics including motor and non-motor symptoms, and is correlated to diminished quality of life due to the progressive difficulty with oral intake, weight loss, dehydration, malnutrition, and reduction in social activities (Barichella et al., 2013; Gong et al., 2022; Kalf et al., 2012). Dysphagia for individuals with PD may occur in every stage of the disease and may involve the oral, pharyngeal, or esophageal aspects of swallowing (Pflug et al., 2018). Dysphagia is often undetected in the early stages of PD and frequently increases in severity as the disease progresses (Miller et al., 2009; Sapir et al., 2008). Aspiration pneumonia secondary to dysphagia is a frequent cause of hospitalizations for those with PD and can result in severe complications and mortality (Akbar et al., 2015; Fabbri et al., 2019; Fujioka et al., 2016; Martinez-Ramirez et al., 2015).
Research demonstrates the importance of early screening, diagnosis, and treatment for dysphagia secondary to PD which may reduce associated complications (Gong et al., 2022; Miller et al., 2009). Despite the prevalence of dysphagia for those with PD, many individuals with PD do not report complaints of dysphagia when asked as they may not be aware of swallowing dysfunction (Monteiro et al., 2014). Signs and symptoms indicative of dysphagia for those with PD may include increased duration of meal times, difficulty swallowing tablets, globus, coughing and choking during oral intake, changes in voice aft3er swallowing, weight loss, and drooling (Buhmann et al., 2019; Nóbrega et al., 2008; Roy et al., 2007; Sampaio et al., 2014; Troche et al., 2016; Wallace et al., 2000).
Although the clinical swallow evaluation can be helpful in the assessment of swallow function for those with dysphagia, the modified barium swallow study (MBSS) or flexible endoscopic evaluation of swallowing (FEES) provide higher sensitivity in determining the presence of swallowing abnormalities, issues undetectable at the bedside such as silent aspiration, and are necessary in identifying underlying impairments and creating individualized care plans (Cosentino et al., 2022; Langmore et al., 2022; Martin-Harris et al., 2020). Intervention modalities to address dysphagia secondary to PD may include compensation, swallowing maneuvers, expiratory muscle strength training, traditional swallowing exercises, and neuromuscular electrical stimulation (López-Liria et al., 2020).
Interdisciplinary management of PD is key for patient success. Patients and families/caregivers should be provided with education and counseling regarding treatment decisions, end of life care, financial planning, and additional support as needed (Eggers et al., 2018; Espay et al., 2018).
To learn more about PD, check out the references cited.
