What are the treatment options for essential tremor in an elderly patient with potential Impaired renal function?

From the Guidelines

For elderly patients with essential tremor, propranolol is a recommended first-line medication option, with a dosage of 20-320 mg daily in divided doses, due to its established efficacy and safety profile, as supported by a recent study published in 2022 1. When considering medication options for essential tremor in elderly patients, it is crucial to prioritize those with a strong evidence base and minimal risk of adverse effects.

• Propranolol, a beta-blocker, has been used to treat essential tremor for over 40 years and is considered a viable option, with other beta-blockers like metoprolol potentially being effective as well, depending on the individual case 1.
• The dosage of propranolol should be adjusted according to the patient's response and tolerance, starting with lower doses and gradually increasing as needed, to minimize the risk of side effects.
• Alternative medications, such as primidone, topiramate, gabapentin, or benzodiazepines like clonazepam, may be considered if propranolol is not effective or tolerated, but their use should be guided by the patient's specific needs and medical history.
• Non-pharmacological approaches, including avoiding caffeine and tremor-triggering medications, using weighted utensils, and considering occupational therapy, are also important components of a comprehensive treatment plan.
• In cases where medications are ineffective and the tremor significantly impacts quality of life, surgical options like deep brain stimulation may be considered, although advanced age may limit surgical candidacy.

From the FDA Drug Label

The pharmacokinetics of topiramate in elderly subjects (65 to 85 years of age, N=16) were evaluated in a controlled clinical study The elderly subject population had reduced renal function [creatinine clearance (-20%)] compared to young adults. Topiramate clearance is decreased in the elderly only to the extent that renal function is reduced As recommended for all patients, dosage adjustment may be indicated in the elderly patient when impaired renal function (creatinine clearance rate ≤70 mL/min/1. 73 m2) is evident.

Medications for essential tremor in elderly patients may include topiramate, but dosage adjustment may be necessary due to reduced renal function.

• Key considerations:
  • Reduced renal function in elderly patients
  • Dosage adjustment may be indicated when creatinine clearance rate ≤70 mL/min/1.73 m2
  • Monitor renal function in elderly patients 2 It is essential to weigh the potential benefits and risks of using topiramate in elderly patients with essential tremor, considering the potential for reduced renal function and the need for dosage adjustment. 2

From the Research

Medications for Essential Tremor in Elderly Patients

• The first line of treatment for limb tremor is pharmacotherapy with propranolol or primidone, which can reduce tremor severity by half 3.
• Other medications that may be effective in reducing limb tremor include:
  • Alprazolam, atenolol, gabapentin, sotalol, and topiramate (Level B) 4.
  • Clonazepam, clozapine, nadolol, and nimodipine (Level C) 4.
• Botulinum toxin A may reduce hand tremor, but is associated with dose-dependent hand weakness (Level C) 4.
• Topiramate is considered clinically useful for doses higher than 200 mg/day 5.
• Propranolol, primidone, and topiramate (>200 mg/day) are the pharmacological interventions with robustly supported efficacy 5.

Surgical Interventions

• Unilateral Ventralis intermedius thalamic DBS, radiofrequency thalamotomy, and MRI-guided focused ultrasound thalamotomy are considered possibly useful for limb tremor 5.
• Deep brain stimulation (DBS) and thalamotomy are highly efficacious in reducing tremor, but carry a small risk of major complications (Level C) 4.
• Surgical interventions may be considered for medication-refractory and functionally disabling tremor 3.

Treatment Considerations

• The treatment of essential tremor depends on the tremor severity, location, and risk-benefit ratios 6.
• A recent consensus classification for essential tremor has included a new subgroup, 'Essential tremor plus', who may require a different treatment approach 3.
• Polypharmacy may be supported in some cases, and other agents such as ethanol, benzodiazepines, gabapentin, levetiracetam, and zonisamide may be effective 6.