Combined therapy of Di-Huang-Yi-Zhi with Donepezil in patients with Parkinson's disease dementia

Here we conducted a randomized and double-blind study attempting to explore the safety and efficacy of combined therapy of Di-Huang-Yi-Zhi (DHYZ) with donepezil in treating Parkinson's disease dementia (PDD). Sixty PDD patients were included and randomly divided into control group and DHYZ group. All patients were given donepezil (5 mg last for a month, then 10 mg for the rest months, once daily), while patients in DHYZ group were additionally administrated with DHYZ (150 ml, twice daily). The measurement subjects included mini-mental state examination (MMSE), Montreal cognitive assessment (MoCA), Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog), the Barthel Index for activities of daily living (ADL) and Traditional Chinese medical (TCM) symptoms before and after treatment in this study. The whole study lasted for six months. Significant differences were observed on MMSE, MoCA, ADAS-Cog, ADL and TCM in both control and DHYZ group (P < 0.05 or P < 0.01) before and after drug treatment. Furthermore, there were more obvious changes of MMSE, MoCA, ADAS-Cog, ADL and TCM scores compared the DHYZ group with the control group (P < 0.01) which suggested the DHYZ group showed a more effective improvement on cognition, behavior as well global function. In conclusion, the combined therapy of DHYZ with donepezil showed a more effective improvement in PDD and the underlying mechanism may be related to the synergic amelioration of cholinergic system between them.