Efficacy of Facial Botulinum Toxin A Injections in Alleviating Neuropsychiatric Symptoms in Parkinson's Disease Patients: An Open-Label, Nonrandomized Controlled Trial.

[BACKGROUND AND PURPOSE] Parkinson's disease (PD), a prevalent neurodegenerative disorder characterized by motor impairments, frequently accompanied by neuropsychiatric symptoms that significantly impair daily functioning and quality of life. The present study aimed to assess the efficacy of botulinum toxin A (BTX-A) in alleviating neuropsychiatric symptoms among PD patients.

[METHODS] This is an open-label, nonrandomized controlled trial. The subscales of the Cornell Medical Index, including somatization, anxiety, depression, maladjustment, sensitivity, anger, and tension, were used to evaluate neuropsychiatric symptoms. The study compared neuropsychiatric health status among 97 PD patients with neuropsychiatric symptoms, divided into two groups: BTX-A (n = 58) and citalopram hydrobromide (CH; n = 39). The BTX-A group received local injections targeting the bilateral glabella, orbicularis oculi muscle, forehead, bilateral lateral canthus, and temporal area. Patients in the CH group received daily doses ranging from 10 to 40 mg. The efficacy of BTX-A was assessed before and eight weeks after treatment, with outcomes compared to those of the CH group.

[RESULTS] The BTX-A group showed significant reductions in somatization (p = 0.028), tension (p < 0.001), anxiety (p = 0.001), depression (p = 0.002), sensitivity (p = 0.006), and total scores (p = 0.009) at 8 weeks after treatment. Both the BTX-A and CH groups demonstrated significant reductions in neuropsychiatric symptoms, with BTX-A showing comparable efficacy to CH (p > 0.05 for all parameters). Additionally, both groups showed comparable neuropsychiatric symptom improvement rates (64.3% vs. 73.7%, p > 0.05). These rates were calculated based on reductions in overall neuropsychiatric symptom severity scores.

[CONCLUSIONS] In summary, BTX-A demonstrates efficacy in reducing multiple neuropsychiatric symptoms (such as tension, anxiety, depression, sensitivity, etc.) in PD, with comparable effectiveness to CH, supporting its consideration as an alternative therapeutic option.