Efficacy and safety of ferulic acid and Angelica archangelica extrac in patients with mild cognitive impairment (MCI): Double blind placebo-controlled study

INTERVENTION: Intervention type:DRUG. Intervention1:Treatment, Dose form:CAPSULE, Route of administration:ORAL. Control intervention1:Mild Cognitive Impairment, Alzheimer disease, Dose form:CAPSULE, Route of administration:ORAL. CONDITION: Mild Cognitive Impairment, Alzheimer disease PRIMARY OUTCOME: MMSE, WMS‐R. Timepoint:Screening visit, 6 months, 12 months. SECONDARY OUTCOME: MRI, FDG‐PET, PIB‐PET. Timepoint: Screening visit, 12 months. INCLUSION CRITERIA: 1.MCI outpatients older than 60 years old at informed consent. 2.Patients with MCI who fulfilled the MCI criteria (Reisberg(1991); MayoClinic,Petersen(1995)). 3.MMSE score 20‐26 points and CDR score 0.5 or 1. 4.Patient could be distinguished from other dementia disorders. 5.Patient can administrate the tablets and patient and patient's family can manage taking medicine. 6.Written informed consent of patient and patient's family.