What are the treatment options for swallowing problems in patients with Parkinson's disease?

Treatment Options for Swallowing Problems in Parkinson's Disease

Optimization of dopaminergic medication should be the first-line approach for managing swallowing problems in Parkinson's disease patients, followed by individualized rehabilitation treatments including bolus modification, postural maneuvers, and exercise programs. 1

Assessment and Diagnosis

Before initiating treatment, proper assessment of dysphagia is essential:

• Dysphagia affects over 80% of Parkinson's disease (PD) patients during the course of their disease 1, 2
• Silent aspiration is common in PD, with only 20-40% of patients aware of their swallowing dysfunction 1
• Screening is recommended for:
  • Patients with Hoehn & Yahr stage above II
  • Those with weight loss, low BMI (<20 kg/m²)
  • Patients with drooling or sialorrhea
  • Those with dementia
  • Any patient showing signs of dysphagia 1

Diagnostic Tools

• PD-specific questionnaires (SDQ or MDT-PD) can identify dysphagia with 81% sensitivity 1
• Water swallow test measuring average volume per swallow (significantly lower in PD patients: 13 ml vs 21 ml in controls) 1
• Gold standard instrumental assessments:
  • Fiberoptic Endoscopic Evaluation of Swallowing (FEES)
  • Videofluoroscopic Swallowing Study (VFSS) 1, 2

Treatment Algorithm

1. Pharmacological Management

First-Line: Optimize Dopaminergic Medication

• Both dopaminergic and non-dopaminergic mechanisms contribute to dysphagia in PD 1
• Dopaminergic medication optimization may improve swallowing function in some patients 1
• Test the effect of dopaminergic treatment on swallowing function during ON-phase 1

Important caveat: Recent research suggests limited impact of dopaminergic medication on swallowing function. A study found no significant differences in swallowing between OFF/ON states 3, and another study showed that improvement in general parkinsonian signs was not a reliable indicator of improved swallowing 4.

Adjunctive Pharmacological Options

For patients with delayed swallow reflex:

• TRPV1 agonists (capsaicinoids, piperine) can improve swallow safety by decreasing latency of swallow reflex 1
• Dopaminergic agents may normalize the onset of pharyngeal swallow 1

2. Rehabilitation Treatments

Bolus Modification

• Thickened liquids improve swallowing safety but may increase oropharyngeal residue 1, 3
• Pudding-thick liquids result in lower penetration-aspiration scores compared to thin liquids 1
• Honey-thick liquids are more effective than nectar-thick liquids or chin-down posture in preventing aspiration 1

Postural Maneuvers

• Chin-down posture is less effective than thickened liquids for preventing aspiration 1
• Note: 39% of PD patients and 50% of PD patients with dementia may still aspirate despite these interventions 1

Exercise Programs

• Expiratory Muscle Strength Training (EMST) has shown improvement in:
  • Cough function
  • Penetration/aspiration scores
  • Hyolaryngeal complex function 1
• Oral motor exercise programs can improve:
  • Strength and range of motion of mouth, larynx, and pharynx
  • Oral control of bolus
  • Coordination between breathing and swallowing 1

3. Advanced Interventions

Neuromuscular Electrical Stimulation (NMES)

• May improve swallowing function when combined with behavioral swallowing treatment 1
• More effective than behavioral swallowing treatment alone 1

Video-Assisted Swallowing Therapy (VAST)

• Can be used as a therapeutic measure during FEES 1
• Shows some evidence of effectiveness 1

Nutritional Considerations

• Monitor for side effects of PD medications that may affect nutritional status (nausea, vomiting, abdominal pain, dyspepsia, constipation, weight decrease) 1
• Levodopa may be associated with impaired nutritional status and risk for malnutrition 1
• Monitor homocysteine levels and vitamin B status in patients on levodopa 1
• Consider vitamin B supplementation to prevent neuropathy and other complications associated with hyperhomocysteinemia 1

Clinical Pearls and Pitfalls

• Pneumonia is the most frequent cause of death in PD and is substantially related to dysphagia 1, 2
• Silent aspiration is common and cannot be reliably detected by clinical assessment alone 1
• Improvement in motor symptoms does not necessarily correlate with improvement in swallowing function 4
• Fluctuating dysphagia with deterioration during the OFF-state should be treated by optimizing dopaminergic medication 2
• Carbidopa-levodopa is available as orally disintegrating tablets that do not require water to aid dissolution or swallowing, which may be helpful for patients with dysphagia 5