To explore the curative effect and safety of botulintum toxin A (BTX-A) on depressive disorder in patients with Parkinson′s disease (PD).

Forty-two cases of PD with depression prospectively recruited in the Second Hospital Affiliated to Soochow University from August 2016 to November 2018 were divided into two groups: 28 patients in BTX-A group (administered with 100 U BTX-A injection on patients′ eyebrow, forehead, bilateral lateral canthus and temporal region at 20 loci), 14 patients in sertraline (control) group (administered with 50-100 (55.36±14.47) mg/d sertraline). The scores of Hamilton Depression Rating Scale (HAMD), Self-rating Depression Scale (SDS), Hamilton Rating Scale for Anxiety (HAMA), Self-rating Anxiety Scale (SAS) after treatment for 2 weeks, 4 weeks, 8 weeks and 12 weeks were compared with the scores of each emotional rating scale for baseline respectively. Meanwhile, the differences in the scores of each emotional scale between the two treatment groups were compared. In addition, the remission rates of depression and anxiety (defined as HAMD, HAMA scores<7) at each follow-up time point between the two groups were compared to evaluate the efficacy and safety of BTX-A in the treatment of PD patients with depression.

The scores of HAMD, HAMA, SDS, SAS in the BTX-A group and the sertraline group reduced compared to baseline after treatment (at the 2nd, 4th, 8th, 12th weeks). The scores of HAMD and SDS in the BTX-A group (HAMD scores: F=12.930, P<0.01; SDS scores: F=5.022, P=0.001) and those in the sertraline group (HAMD scores: F=2.883, P=0.030; SDS scores: F=3.427, P=0.013) were significantly lower compared to baseline, but there was no statistically significant difference in the scores of HAMD and SDS between the two groups (P>0.05). HAMD score showed that the remission rate of depression in the BTX-A group (17.9% (5/28), 35.7% (10/28)) was higher than that of the sertraline group (2/14, 4/14) at the 2nd and 4th weeks. At the 8th and 12th weeks, the remission rate of depression in the sertraline group (7/14, 9/14) was higher than that of the BTX-A group (46.4% (13/28), 53.6% (15/28)). There was no statistically significant difference in remission rate of depression between the two groups at each follow-up time point (P>0.05). There was no statistically significant difference in HAMD scores between males and females in the BTX-A group (P>0.05). Two of the 28 patients in the BTX-A group had frown muscle stiffness, which lasted for two weeks and improved in one month. Two patients in the sertraline group had headache and dizziness, and two patients had dry mouth and nausea, which improved after two weeks. There was no statistically significant difference in the incidence of adverse reactions between the two groups (P=0.197).

BTX-A intraocular facial muscle injection can significantly improve the depressive symptoms of PD patients, and the effect lasts for a long time, with low incidence of side effects and high safety, which can be considered as a safe and effective new method for PD patients with depressive symptoms.

Parkinson disease; Depressive disorder; Botulintum toxins, type A; Treatment outcome