Evaluating efficacy and safety of Saffron add-on treatment in improvement of motor and depressive symptoms of patients with Parkinson’s disease: A randomized, double-blind, placebo-controlled clinical trial

Abstract

Aim

Evidence has highlighted neuroprotective effects of saffron in animal models of Parkinson’s disease (PD). The present study investigated the efficacy and safety of add-on saffron on motor and depressive symptoms of patients with PD.

Methods

This study was an 8-week, randomized, double-blind, and parallel-group clinical trial. Known cases of PD with depression were randomized to receive either a routine treatment (levodopa or levodopa-equivalent dose of a dopamine agonist) plus saffron capsule (15 mg bid) or routine treatment plus placebo. All participants were assessed using the Hamilton Depression Rating Scale (HAMD), Geriatric Depression Scale-30 (GDS-30), item 3 of Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part 1, MDS-UPDRS part 3, and H and Y scale at baseline and at week 8.

Results

A total of 52 patients (25 in saffron and 27 in placebo groups) were included. Our results demonstrated that saffron could not improve motor symptoms of PD patients (F=0.53, df=1, p=0.424). However, repeated-measures analysis showed a significant effect of time $\times$ treatment (F=8.24, df=1, p=0.006) on HAMD scores, indicating a greater improvement of depressive symptoms in saffron compared to placebo groups. Our study showed nonsignificant findings regarding the secondary outcome measures (GDS-30, item 3 of MDS-UPDRS part 1, and H and Y scale). We showed that treatment with saffron is safe in PD.

Conclusion

We substantiated that add-on treatment with saffron significantly improved depression, but not motor symptoms, in PD. Further trials with larger sample sizes and longer follow-ups are needed to confirm our findings.