The Effect of Adding Kami-guibi-tang to Acetylcholinesterase Inhibitor Treatment on the Cognitive Function of Mild Alzheimer's Disease Patients: Study Protocol of a Randomized, Placebo-Controlled, Double-Blind Pilot Trial

Abstract

Background: Alzheimer's disease (AD) is a chronic neurodegenerative disease that causes disorientation, mood swings, problems with language, and difficulty remembering recent events. Acetylcholinesterase inhibitors (AchEIs) and memantine have been used to slow the course of the disease, but they can neither modify its progression nor prevent disease onset. Previous studies have suggested that Kami-guibi-tang (KGT) could be beneficial for supporting cognitive function in AD patients, but few clinical trials have been published. This pilot study aimed to evaluate the effect of KGT in improving cognitive function in AD patients. Methods: The study will be a randomized, placebo-controlled, double-blind, single-center trial conducted using subjects diagnosed with mild AD by neurologists. Study subjects will be randomly assigned to either a treatment or control group. The treatment group will receive KGT granules for 24 weeks, while the control group will receive placebo granules. AchEI administration will be maintained in both groups during the entirety of the study. Subjects will be assessed using the following exams: the Seoul Neuropsychologic Screening Battery (SNSB) for cognitive function; brain magnetic resonance imaging (MRI) for brain metabolite, neurotransmitter, and cerebral blood flow (CBF) measurements; the Korean version of Quality of Life-Alzheimer's Disease (KQol-AD) for quality of life; the Caregiver-Administered Neuropsychiatric Inventory (CGA-NPI) for neurobehavioral symptoms; blood tests for amyloid and tau proteins and general blood parameters; and electrocardiography (ECG) before and after taking the medication. Discussion: Our findings will provide insight into the feasibility of large-scale trials to consolidate evidence for the efficacy of KGT for dementia treatment. Registration ID in CRIS: KCT0002904 (Clinical Research Information Service of the Republic of Korea).