Efficacy and safety of Shenmayizhi decoction as an adjuvant treatment for vascular dementia Study protocol for a randomized controlled trial

Background: Vascular dementia (VaD) is the second most common cause of dementia. The treatment of VaD still remains a challenge so far. Traditional Chinese Herbal medicine is a promising therapy due to their multiple components and targets. Shenmayizhi decoction (SMYZD), a Chinese Herbal prescription, has been reported its effective in alleviating cognitive dysfunction in clinical practice. However, strong clinical research of SMYZD in the treatment of VaD was lack. Therefore, we design this study to evaluate the adjuvant role of SMYZD in the treatment of VaD. Methods: This is a multicenter, randomized, blind, controlled trial. A total of 196 eligible patients will be assigned to receive Ginkgo biloba extracts (GBEs) plus SMYZD granule or GBEs plus SMYZD mimetic granule in a 1:1 ratio. The duration of the trial will be 12 weeks, and a follow-up will be performed at the 24th week. The primary outcomes are the National Institute of Health stroke scale (NIHSS) and the Alzheimer Disease Assessment Scale-cognitive subscale (ADAS-cog). The secondary outcomes include the Mini-Mental State Examination (MMSE), the traditional Chinese Medicine (TCM) syndrome scale, Activities of Daily Living (ADL), concentrations of hypersensitive C-reactive protein (Hs-CRP), neuron-specific enolase (NSE) and homocysteine (HCY) in serum. Researchers will record any adverse events throughout the trial. Discussion: This study will provide evidences to evaluate the efficacy and safety of SMYZD in combination with GBEs in treatment of VaD, as well as the adjuvant role of SMYZD in combination.