Treatment of Neuropsychiatric Symptoms in Parkinson's Disease With Botulinum Toxin A: A 12 week Randomized, Double-Blind, Placebo-Controlled Trial.

Objective: The study aimed to evaluate the impact of Botulinum toxin A (BoNT/A) on neuropsychiatric symptoms in Parkinson's disease (PD) patients.

Methods: A total of 125 PD patients and an equal number of age- and gender-matched healthy controls were involved. Mental health status was assessed using the Cornell Medical Index (CMI) self-assessment questionnaire. Sixty-four PD patients exhibiting neuropsychiatric symptoms were selected for the controlled study and randomly grouped into treatment and control groups. The treatment group received BoNT/A injections, while the control group received a placebo. The primary outcome measures included depression scores from the CMI and the proportion of patients displaying improvement in neuropsychiatric symptoms at 8 weeks post-treatment. The secondary outcome was other CMI scores at 4, 8, and 12 weeks post-treatment.

Results: The outcomes revealed that PD patients had significantly higher scores in various neuropsychiatric factors compared to healthy controls. At 4 weeks post-treatment, the treatment group displayed improvements in depression and tension. At 8 weeks post-treatment, they exhibited significant reductions in depression, anxiety, sensitivity, and tension compared to the control group. Moreover, a notably higher percentage of patients in the treatment group showed improvement in neuropsychiatric symptoms compared to the control group. At 12 weeks post-treatment, the treatment group exhibited significant improvements in somatization, depression, sensitivity, and tension.

Conclusion: PD patients commonly experience multiple neuropsychiatric symptoms, and BoNT/A has demonstrated efficacy in alleviating these symptoms. Specifically, BoNT/A was found to effectively alleviate somatization, tension, anxiety, depression, and sensitivity in PD patients.