Multiple Sclerosis and Dysphagia
Multiple sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system affecting approximately 2.8 million people worldwide. While the most recognised symptoms of MS are motor weakness, visual disturbance, and fatigue, dysphagia affects an estimated 30–45% of MS patients at some point during their disease course, rising to 65% or more in advanced disease.
Unlike the dysphagia seen in acute stroke (sudden onset, typically recovering over weeks) or Parkinson’s disease (gradually progressive with on/off medication windows), MS dysphagia has its own distinct clinical pattern: relapsing-remitting at first, often subtle, strongly influenced by fatigue, and prone to significant day-to-day fluctuation. This guide provides clinicians, caregivers, and patients with a detailed framework for assessment and management.
1. Epidemiology and phenotypes
Overall prevalence
- Early relapsing-remitting MS (RRMS): 15–25% have some degree of swallowing dysfunction on objective testing, though many are asymptomatic
- Secondary progressive MS (SPMS): 40–55%
- Primary progressive MS (PPMS): 40–60%
- Advanced MS (EDSS ≥ 7.5): 65–75%
Subclinical dysphagia
Up to 40% of MS patients with objective swallowing abnormalities on VFSS have no subjective complaints. This is one of the most important clinical facts about MS dysphagia: patients often don’t know they’re having problems until aspiration pneumonia or weight loss prompts investigation.
Relationship to MS phenotype
- More prominent in progressive phenotypes
- Correlated with overall disability (EDSS score)
- Brainstem involvement dramatically increases dysphagia risk
- Cerebellar involvement affects oral phase coordination
- Pseudobulbar palsy (upper motor neuron bulbar dysfunction) common in advanced disease
2. Pathophysiology — why swallowing fails in MS
MS dysphagia is multifactorial, reflecting lesions throughout the neural swallowing network:
Cortical lesions
- Affect voluntary initiation of swallowing
- Reduce awareness of bolus in the mouth
- Impair coordination of preparatory tongue movements
Brainstem lesions (most clinically important)
- Nucleus tractus solitarius disruption → reduced afferent input from pharynx
- Nucleus ambiguus disruption → weakness of pharyngeal constrictors
- Cranial nerve nuclei (V, VII, IX, X, XII) — any can be affected
- Hypoglossal nucleus → tongue weakness
- Result: delayed swallow initiation, weak pharyngeal stripping, cricopharyngeal dysfunction
Cerebellar lesions
- Impaired coordination of oral phase
- Ataxic, uncoordinated tongue movements
- Difficulty forming cohesive bolus
Cognitive/attention effects
- Frontal lesions affect attention to feeding task
- Executive dysfunction affects meal planning
- Impaired self-cueing to swallow
Pseudobulbar palsy
- UMN corticobulbar tract lesions
- Emotional lability
- Exaggerated gag reflex
- Hypertonic pharynx
Fatigue — the unique MS factor
This is what makes MS dysphagia distinctive. Unlike stable structural lesions, MS patients often swallow safely at the start of a meal but become unsafe by the end. Fatigue affects:
- Pharyngeal muscle contraction strength (decreased over 15–20 minutes)
- Cognitive attention to swallow
- Postural endurance (slumping during the meal)
- Overall meal endurance
A patient who passed a bedside screen at 10 am may aspirate at 6 pm dinner, especially after an active or stressful day.
3. Clinical presentation
Oral phase findings
- Drooling (sialorrhea) — often early
- Difficulty forming or moving the bolus
- Food residue in the buccal sulci after swallowing
- Prolonged meal duration
- Inability to chew tough foods
Pharyngeal phase findings
- Delayed swallow trigger (>2 seconds)
- Reduced laryngeal elevation
- Weak pharyngeal peristalsis
- Post-swallow residue in valleculae and pyriform sinuses
- Penetration-aspiration (often silent in MS)
Oesophageal phase findings
- Impaired oesophageal peristalsis (in up to 25%)
- Reflux
- Feeling of food “stuck” retrosternally
MS-specific presentations
- Bulbar attacks: Acute relapse presenting as new-onset dysphagia, dysarthria, sometimes weakness of face/tongue — must be distinguished from other causes and often responds to corticosteroids
- Fatigable dysphagia: Worsening through a meal, better in the morning
- Stress-induced dysphagia: Worsens under emotional or cognitive stress
- Temperature-sensitive dysphagia (Uhthoff phenomenon): Heat worsens symptoms; warm meals and hot drinks may be harder to manage than cool ones
4. Assessment
Screening
- EAT-10 (Eating Assessment Tool): sensitive screen, score ≥3 warrants referral
- SWAL-QoL for broader quality-of-life impact
- DYMUS questionnaire: MS-specific, 10-item, validated for MS population
Bedside clinical assessment
- Full cranial nerve exam
- Facial symmetry at rest and with movement
- Tongue strength, range of motion
- Palatal elevation, gag reflex
- Voice quality (dysphonia, wet voice)
- 3-oz water test: positive predictive value 76% for aspiration
- Cervical auscultation — a listening tool for post-swallow residue
Instrumental assessment
Videofluoroscopic Swallow Study (VFSS / MBSS):
- Gold standard for visualising all phases
- Essential baseline for new-onset MS dysphagia
- Should be repeated at ~12-month intervals in progressive MS or after relapses affecting bulbar function
- Specifically look for: delayed trigger, residue, laryngeal penetration, aspiration (silent or symptomatic), oesophageal dysmotility
Fiberoptic Endoscopic Evaluation of Swallowing (FEES):
- Can be done bedside
- No radiation exposure — suitable for pregnant MS patients
- Directly visualises pharyngeal structures
- Allows evaluation of sensation via tactile testing (FEESST)
- Ideal for monitoring disease progression
Timing of assessment
- At MS diagnosis (baseline, even if asymptomatic)
- After any relapse involving bulbar or cranial nerve symptoms
- When new subjective complaints arise
- When weight loss is unexplained (>5% in 6 months)
- When aspiration pneumonia occurs
- Before starting tube feeding decisions
- Every 6–12 months in progressive phenotypes
5. Treatment — compensatory strategies
Postural adjustments
- Upright 90° posture during and after meals
- Head tuck / chin tuck during swallow (narrows airway entrance)
- Head rotation to the weaker side (directs bolus to stronger side)
- Head tilt to the stronger side
Bolus modification
- IDDSI Level 5 (Minced & Moist) for patients with oral phase weakness
- IDDSI Level 6 (Soft & Bite-Sized) if tongue coordination is the main issue
- IDDSI Level 4 (Pureed) when chewing is significantly impaired or endurance is poor
- Thickened liquids (IDDSI Level 2–3) to reduce aspiration risk
- Small bite sizes (teaspoon or smaller)
- Avoid mixed textures (soups with solid pieces, bread with liquids)
Pacing and fatigue management
This is the most underappreciated aspect of MS dysphagia management. Strategies:
- Rest before meals: 30–60 minute rest immediately pre-meal
- Divide into smaller, more frequent meals: 6 small meals better than 3 large
- Prioritise breakfast: MS fatigue is often worst in afternoon and evening, so frontload nutritional intake
- Limit meal duration to 20–25 minutes: beyond this, fatigue degrades swallow safety
- Rest mid-meal: 2–3 minute pause every 5–10 minutes
- Stop eating when fatigue begins: this is a non-negotiable safety rule
- Avoid meals immediately after physical exertion
- Heat management: avoid very hot drinks during summer; consider cool/room-temperature meals during hot weather (Uhthoff phenomenon)
6. Treatment — rehabilitation exercises
Evidence-based interventions for MS dysphagia:
Expiratory Muscle Strength Training (EMST)
- Most evidence-supported exercise in MS
- Handheld device providing resistance at 75% maximum expiratory pressure
- 25 reps × 5 sets per day, 5 days per week
- 5–8 weeks produces measurable improvements in swallow safety and cough strength
Shaker exercise (head-lift)
- Supine position, lift head 30° while keeping shoulders on bed
- 1 minute × 3 reps per day
- Strengthens suprahyoid muscles, improves upper oesophageal sphincter opening
- Caution in MS patients with cervical spine issues or severe fatigue
Mendelsohn manoeuvre
- Voluntarily prolong laryngeal elevation during swallow
- Improves hyoid-laryngeal movement
- Requires cognitive effort — not ideal for patients with cognitive impairment
Effortful swallow
- Swallow hard, “as if swallowing a large pill”
- Increases tongue base retraction
- Most useful for pharyngeal residue management
- Tongue press against pressure bulb
- Evidence in MS population more limited but shows promise
- Must be calibrated to patient’s current strength
Neuromuscular electrical stimulation (NMES)
- Contested evidence base
- May help some patients with pharyngeal weakness
- Not first-line in MS
7. Medical management
Disease-modifying therapy (DMT) implications
MS DMTs do not directly treat dysphagia, but prevention of relapses prevents progression of dysphagia. A patient with established bulbar involvement should be on an effective DMT to prevent further lesion accumulation.
Acute bulbar relapse
- High-dose IV corticosteroids (typically methylprednisolone 1 g IV × 3–5 days)
- Plasma exchange for refractory cases
- Early intervention is critical — bulbar relapses respond to treatment if caught early
- Swallowing function often improves alongside neurological recovery
Spasticity management
- Baclofen, tizanidine can help with pseudobulbar features
- Caution: these drugs can increase sedation and worsen aspiration risk if over-dosed
Sialorrhea (drooling) management
- Glycopyrrolate (oral) — first-line
- Hyoscine patches
- Amitriptyline (if also depression)
- Botulinum toxin injections to parotid and submandibular glands (by ENT)
Pseudobulbar affect (emotional lability)
- Dextromethorphan-quinidine combination (Nuedexta)
- Can improve patient participation in meals if laughing/crying episodes are triggered by eating
8. Nutrition and hydration
Monitoring
- Body weight weekly during periods of changing dysphagia
- BMI trends
- MUST (Malnutrition Universal Screening Tool) every 3 months
- Labs: albumin, prealbumin, vitamin D, B12, iron (MS patients often have deficiencies)
- 24-hour food diary to assess adequacy
Hydration
- MS patients are often dehydrated
- Thickened liquids reduce compliance — provide variety (thickened juices, smoothies, broths)
- Monitor urine colour daily
- Oral electrolyte drinks at appropriate thickness
Enteral feeding decision
When oral intake cannot maintain nutrition and hydration:
PEG (Percutaneous Endoscopic Gastrostomy) considerations in MS:
- MS patients may live many years with severe disability
- PEG is not “giving up” — it is nutritional support
- Can supplement oral intake (partial feeding) rather than replace it
- Decision should involve neurologist, SLP, dietitian, patient, family
Timing:
- Weight loss >10% over 6 months despite optimised oral intake
- Recurrent aspiration pneumonia (2+ in 6 months)
- Meal time >60 minutes consistently
- Severe dehydration requiring IV rehydration
Contraindications:
- Severe thrombocytopenia
- Uncorrectable coagulopathy
- Severe gastric motility disorder
- Patient refusal (per advance directive)
9. Aspiration pneumonia prevention
Aspiration pneumonia is the leading cause of hospitalisation and significant cause of mortality in advanced MS.
Five-layer defence
- Oral hygiene — critical
- Brushing 2× daily minimum
- Chlorhexidine 0.12% mouthwash daily
- Professional dental care every 6 months
- MS-specific adaptations for hand weakness: electric toothbrush, toothbrush handles with large grips
- Bolus management
- Appropriate IDDSI levels
- Supervised eating during fatigue-affected periods
- No mixed textures
- Positioning
- 90° upright
- 30 minutes upright post-meal
- Chest physiotherapy
- Deep breathing exercises
- Assisted cough if cough is weak
- Postural drainage if chronic secretions
- Vaccination
- Annual influenza
- Pneumococcal (PCV13 + PPSV23)
- COVID-19 per current recommendations
Practical advice for patients and caregivers:
Meal timing around MS fatigue
- Morning: Eat biggest meal of the day
- Late morning/midday: Secondary meal
- Evening: Smallest meal or snack
- Pre-sleep: Light snack only if needed
Rest-feeding cycles
- Rest 30 minutes before meals
- 2–3 minute break every 10 minutes during a meal
- Alternate liquid and solid bites to reduce pharyngeal fatigue
Caregiver support during fatigue
- A caregiver may need to assume more active feeding role as fatigue worsens
- Hand-over-hand feeding (caregiver guides patient’s hand) preserves dignity and autonomy
- Pacing by caregiver: “Ready for next bite?” — cueing helps maintain attention
Energy-dense nutrition
- Add olive oil, butter, cream to foods for calorie density
- Protein supplementation: whey protein, Greek yoghurt, peanut butter
- Consider nutritional supplements (Ensure, Fortisip) between meals
11. Cognitive considerations
MS can cause cognitive impairment in up to 65% of patients, particularly affecting:
- Attention
- Processing speed
- Executive function
- Working memory
Impact on feeding
- Difficulty remembering safe swallowing strategies
- Reduced awareness of food in mouth
- Distractibility during meals
- Forgetting to chew or swallow
Strategies
- Reduce distractions during meals (TV off, quiet environment)
- Single-step verbal cues (“chew”, “swallow”)
- Visual cues (pictures of steps)
- Caregiver presence for attention reinforcement
- Short meals to match attention span
12. Psychological and social impact
Dysphagia has a significant psychological toll in MS. Patients often report:
- Embarrassment eating in public
- Social isolation, avoiding meals with others
- Depression related to lost pleasure in eating
- Anxiety at mealtimes
- Frustration with modified diets
Support strategies
- Refer to MS psychologist or counsellor
- Peer support groups (MS Society, MS Trust)
- Family education — make sure caregivers understand fatigue-related variability
- SLP continuing support throughout disease course
13. Coordinating with the MS multidisciplinary team
MS dysphagia management should be integrated with overall MS care:
- MS neurologist: DMT decisions, relapse management, EDSS monitoring
- Speech-Language Pathologist: Swallowing assessment, therapy, diet recommendations
- Dietitian: Nutritional adequacy, weight monitoring, supplement recommendations
- Physiotherapist: Posture, chest physiotherapy, spasticity management
- Occupational therapist: Adaptive utensils, meal-time positioning
- MS nurse: Patient education, caregiver support, care coordination
- Palliative care: In advanced disease, for symptom management and decision-making
- Gastroenterologist: For oesophageal dysphagia, PEG placement
- Otolaryngologist (ENT): For FEES, botulinum toxin injections, sialorrhea management
14. Advance care planning
All MS patients should have advance directive discussions about dysphagia-related decisions before they are needed:
- Would they want tube feeding if oral intake becomes unsafe?
- Under what conditions?
- Who makes decisions if they cannot?
- What are their goals: length of life vs quality of life?
- Preferred location for end-of-life care
These conversations are best had early, when the patient is cognitively intact and can participate meaningfully.
15. Prognosis
MS dysphagia prognosis varies widely:
- Mild dysphagia in RRMS: often improves with relapse recovery; may be transient
- Subclinical dysphagia in early RRMS: stable for many years with appropriate monitoring
- Progressive dysphagia in SPMS/PPMS: typically continues to worsen slowly; PEG may be needed in advanced disease
- Bulbar relapse: usually improves with corticosteroids; residual deficit variable
Predictors of poor outcome
- Higher EDSS score
- Older age at dysphagia onset
- Cognitive impairment
- Brainstem lesions on MRI
- Rapidly progressive phenotype
Predictors of good outcome
- Early identification and intervention
- Effective DMT preventing relapses
- Comprehensive rehabilitation
- Strong caregiver support
- Good oral hygiene maintenance
16. Key clinical pearls
- MS dysphagia is underdiagnosed. Ask every MS patient at every visit about eating, drinking, and weight — don’t wait for them to complain.
- Fatigue changes everything. A patient who passes a screen may fail later in the day. Always assess during afternoon/evening if possible.
- Silent aspiration is common. Absence of cough does not mean absence of aspiration.
- Bulbar relapse is a medical emergency. Treat with corticosteroids; swallowing function often recovers.
- Oral hygiene is the best prevention tool for aspiration pneumonia — more effective than any texture modification alone.
- Progression is not inevitable. Early DMT + early rehabilitation can keep many patients eating orally for decades.
- PEG is not giving up. In appropriately selected patients, it is nutritional support that may enable continued quality of life.
Final thoughts
MS dysphagia sits at a unique intersection of neurology, rehabilitation, and chronic disease management. It is not a “single event” problem like stroke dysphagia, nor a uniformly progressive problem like ALS. It is variable, fatigue-modulated, and strongly affected by overall disease course.
The best outcomes come from early awareness, systematic monitoring, fatigue-aware management, and a coordinated multidisciplinary team. Patients who are educated about their own swallowing, caregivers who understand the fatigue factor, and clinicians who screen proactively together create the conditions for safe, sustained oral nutrition throughout the disease course.
MS is a life-long condition. Dysphagia is one of many challenges along the way — but with good management, it is rarely the defining one.