What is the prognosis for individuals with Parkinson's disease and dysphasia?

Prognosis for Individuals with Parkinson's Disease and Dysphagia

Dysphagia in Parkinson's disease is associated with poor outcomes, including significantly increased mortality risk, with dysphagia severity at baseline being a strong predictor of death, institutionalization, or progression to Hoehn and Yahr stage 5 (Hazard ratio 2.3,95% CI 1.12-4.4).1

Prevalence and Recognition

• More than 80% of patients with Parkinson's disease develop dysphagia during the course of their disease, with swallowing problems sometimes arising early in the disease course.2, 3
• Dysphagia prevalence based on subjective outcomes is around 35% but increases to 82% when objective measures of swallowing dysfunction are used, indicating many PD patients have silent or unrecognized dysphagia.4, 2
• Only 20-40% of PD patients are aware of their swallowing dysfunction, and less than 10% report dysphagia spontaneously, making active screening essential.4
• Silent aspiration is very common in PD patients with dysphagia, further complicating early detection.4, 2

Mortality and Morbidity Outcomes

• Pneumonia is the most frequent cause of death in Parkinson's disease and is substantially related to dysphagia.4, 2
• In a one-year follow-up study of late-stage PD patients, 20% were dead, institutionalized, or progressed to Hoehn and Yahr stage 5, with dysphagia severity being the strongest predictor of these poor outcomes.1
• Dysphagia is associated with high risk for decreased food and fluid intake, leading to malnutrition, which affects approximately 15% of community-dwelling PD patients.4, 2
• Observational studies of tube-fed elderly patients with Parkinson's disease show high mortality rates, with one study reporting 7% mortality at 1 year in Parkinson's patients with NG-intolerance who received PEG feeding.4

Risk Factors for Dysphagia Development and Progression

• Risk factors for dysphagia in PD include Hoehn and Yahr stage above III, weight loss, BMI below 20 kg/m², drooling/sialorrhea, and dementia.4, 2
• Dysphagia can be present in MS patients with an Expanded Disability Status Scale lower than 2.5 (low disability), suggesting that even early-stage neurological disease can involve swallowing problems.4
• Patients with severe disabilities, cerebellar dysfunction, and long disease duration are at highest risk for dysphagia in neurological conditions like MS, which may have parallels in PD.4

Impact on Quality of Life

• Fear of aspiration, choking, and food modification requirements significantly reduce quality of life in PD patients with dysphagia.4, 2
• Dysphagia complicates medication intake, which can affect symptom control and potentially accelerate disease progression.3
• After one year, late-stage PD patients show worsening of non-motor symptoms, mostly in cognition/mood, urinary and gastrointestinal domains, with functional independence and quality of life deteriorating.1

Screening and Assessment Recommendations

• All PD patients with Hoehn & Yahr stage above II or with weight loss, low BMI, drooling, dementia, or signs of dysphagia should be screened for dysphagia during an ON-phase.4, 2
• Instrumental assessment should be performed in PD patients with high risk for dysphagia, preferably with fiberoptic endoscopic evaluation of swallowing (FEES), or if not available, with videofluoroscopic swallowing study (VFSS).4, 5
• Regular monitoring of body weight and nutritional status is recommended at least yearly and whenever clinical conditions change.2

Management Approaches and Their Impact on Prognosis

• Rehabilitation treatment (adapting bolus characteristics, postural maneuvers, and exercise programs) should be implemented based on multidimensional assessment of swallowing function.4
• Expiratory muscle strength training has shown promise in improving cough and swallow function in PD patients.4, 6
• Fluctuating dysphagia with deterioration during the off-state should be treated by optimizing dopaminergic medication, though the magnitude of levodopa response does not predict overall prognosis in late-stage PD.3, 1

Important Clinical Considerations

• Despite similar levodopa equivalent doses, motor complications may improve in late-stage PD while dysphagia and other symptoms worsen, indicating the complex and potentially non-dopaminergic nature of dysphagia progression.1
• Clinical progression in late-stage PD shows heterogeneity between patients, with some deteriorating rapidly while others remain relatively stable.1
• Deep brain stimulation does not seem to have a clinically relevant effect on swallowing function in PD, though some studies suggest improved swallow timing.3, 6

Conclusion for Clinical Practice

• Early and regular screening for dysphagia in PD patients is essential given its high prevalence, impact on mortality, and the fact that many patients do not report symptoms.4, 2, 7
• Dysphagia management should be prioritized in PD treatment plans, as it represents one of the strongest predictors of poor outcomes including death.1
• A multidisciplinary approach involving neurologists, speech-language therapists, and nutritionists is necessary for comprehensive management of PD dysphagia.8, 7