Comparative Effectiveness of Propranolol and Botulinum for the Treatment of Essential Voice Tremor

Objectives/Hypothesis: To assess the comparative effectiveness of botulinum toxin and propranolol in patients with essential vocal tremor (EVT). Study Design: Individual prospective cohort study. Methods: Study patients were recruited at the Emory Voice Center from patients seeking treatment for EVT. Exclusion criteria included current beta-blocker treatment, spasmodic dysphonia, or other disease that prevented the use of propranolol therapy. A 10-week washout period from prior botulinum toxin treatment occurred before enrollment. Patients were assessed via the Voice-Related Quality-Of-Life (VRQOL) questionnaire, Quality of life in Essential Tremor questionnaire, and blinded perceptual voice assessment. These assessments were made at baseline voice 2 weeks after propranolol therapy and 4 weeks after botulinum toxin injection. Results: Eighteen patients were enrolled. After 2 to 4 weeks of propranolol therapy (with a maximum dosage of 60 mg to 90 mg per day), patients report an average DVRQOL of 9.31. Six patients report significant VRQOL improvement > 10, with the rest reporting changes between -7.5 and 7.5. Fifteen patients were followed for at least 4 weeks after botulinum toxin injection, reporting an average improvement in scaled VRQOL of 22.00. Blinded perceptual voice assessment demonstrates an improvement in overall severity of tremor with botulinum toxin. Conclusions: In some patients with EVT, propranolol led to significant vocal improvement with no major side effects. Although botulinum toxin remains the gold-standard therapy for patients with EVT, propranolol represents a possible alternative or adjuvant therapy for certain patients.