Essential Tremor
✅ Essential Tremor (ET) – one of the most common movement disorders, often inherited in an autosomal dominant pattern.
It is benign in terms of survival 🕊️ but can be socially and functionally disabling.
👉 Many patients worry about Parkinson’s Disease (PD), so accurate differentiation is crucial.
🧑⚕️ Clinical Features
- Presentation: Gradual onset of 4–12 Hz postural/action tremor, typically hands & forearms. ✋
- Head Tremor (Titubation): "Yes–yes" or "no–no" rhythmic nodding; may affect the voice 🎤.
- Voice Tremor: Quavering, shaky voice quality.
- Leg Tremor: Rare but possible.
- Cogwheeling: May be present, without true rigidity.
- Course: Symmetrical, slow progression over years; gait usually normal.
🔍 Differentiation from Parkinson’s Disease (PD)
- ⏳ ET: Postural/action tremor; usually bilateral, improves with alcohol 🍷.
PD: Resting tremor ("pill-rolling"), asymmetrical, no alcohol benefit.
- 🚶 ET: Normal gait & no bradykinesia.
PD: Bradykinesia, shuffling gait, reduced arm swing.
- 🧾 ET: Family history common (autosomal dominant).
PD: Usually sporadic, some genetic forms.
- 👀 Head/voice tremor: Common in ET, rare in PD.
🧪 Investigations
- Clinical Diagnosis: Largely bedside.
- 18F-FDOPA PET: ET = normal striatal uptake; PD = reduced uptake. 🎯
- Thyroid Function Tests (TFTs): Exclude hyperthyroidism.
- Wilson’s Disease Screening: <40 yrs with tremor → caeruloplasmin, serum & urine copper 🧪.
📋 Differential Diagnosis
- Anxiety & Stress Tremor: Situational, transient.
- Parkinson’s Disease: Rest tremor, rigidity, bradykinesia.
- Wilson’s Disease: Young patients, "wing-beating" tremor + other neuro signs.
💊 Management
- Reassurance: Many patients relieved once PD excluded. 🧾
- Lifestyle: Reduce caffeine, stress; small alcohol intake may transiently improve tremor (not long-term therapy).
- Medications:
- 🫀 Propranolol (β-blocker): First-line; reduces tremor amplitude.
- 💊 Primidone (anticonvulsant): Useful if propranolol not tolerated.
- 😊 Mirtazapine: Consider if anxiety/depression co-exist.
- Advanced therapy: Severe/refractory cases → stereotactic thalamotomy or DBS of VIM ⚡
💡 Exam Pearls
• ET = action tremor, symmetrical, family history, improves with alcohol.
• PD = resting tremor, asymmetrical, bradykinesia, rigidity, no alcohol benefit.
• Severe ET → consider DBS of VIM nucleus of thalamus.
📚 References & NICE Guidance
