Effectiveness of Yi-Zhi-An-Shen Granules on cognition and sleep quality in older adults with amnestic mild cognitive impairment: protocol for a randomized, double-blind, placebo-controlled trial

Abstract

BackgroundAmnestic mild cognitive impairment (aMCI) is a syndrome characterized by significant forgetfulness that does not meet the criteria of dementia. Individuals with aMCI are at a bigger risk of progressing to dementia. Current studies suggest good sleep quality is linked with preserved cognition in the elderly, and sleep complaints are common among the elderly with amnesia. Therefore, improving their sleep may be helpful for maintaining and improving their cognitive capacity. According to the theory of traditional Chinese medicine, Yi-Zhi-An-Shen is an herbal compound which may ameliorate forgetfulness and sleep disorders. As growing evidence indicates that gut microbiome is associated with major mental symptoms, a hypothesis was proposed that Yi-Zhi-An-Shen Granules (YZASG) might work by alternating microbial abundance and diversity. In this study, the investigators intend to assess the efficacy of YZASG on global cognition in the elderly suffering from aMCI, and evaluate its safety as well as its potential mechanisms via sleep quality, fecal microbial 16SrDNA and metagenomics analyses, and serum markers. Methods/designThis is a randomized, double-blind, placebo-controlled clinical trial. A total of 80 patients (aged 60~85 years) will be recruited and allocated randomly to a treatment group and a placebo group in a 1:1 ratio, then will be administered YZASG or isodose placebo three times a day. The intervention course is 16 weeks, with an 18-month follow-up. The primary outcome is Alzheimer Disease Assessment Scale-Cognitive subscale (ADAS-cog11). Secondary outcome measures are mini-mental state examination (MMSE), Montreal cognitive assessment (MoCA), Pittsburgh Sleep Quality Index (PSQI), serum concentrations of immunological factors and inflammatory cytokines, fecal microbiota. Fecal microbiota will only be collected at the baseline and endpoint of the intervention. DiscussionThe results of this trial will be conducive to assessing the safety and effectiveness on cognition of YZASG in intervening aMCI among the elderly and determining if it takes effect via the improvement of sleep quality, regulation of gut microbita, concentration of certain serum markers. 4