Glucagon-like peptide-1 analogs for Alzheimers disease -- A systematic meta-analysis

Alzheimers Disease (AD) poses a serious health concern especially for the aging population above the years of 65. An estimated 6 million Americans are diagnosed with Alzheimers Disease, and there are at least 50 million Alzheimers patients in the world. AD affects the daily life of these patients, yet there is no permanent cure. Current treatments involve cholinesterase inhibitors and NMDA-receptor agonists to help alleviate the symptoms. GLP-1 is a peptide often used in the treatment of diabetes. Since there are shared pathological features between diabetes and AD, such as insulin dysfunction and glucose metabolism dysregulation, GLP-1 may be a viable study for AD treatment. To perform a meta-analysis to investigate whether GLP-1 has a beneficiary effect on biological markers and cognitive outcome in AD patients. We searched the following electronic databases: EMBASE, MEDLINE, phycINFO, CINAHL, PubMed, Cochrane CENTRAL, and ClinicalTrials.gov. We only utilized Randomized Control Trials (RCTs) and clinical trials. We also searched with the following Medical Search Headings: Alzheimers Disease, Alzheimer, Alzheimers, and GLP-1. We included 2 randomized, double-blind, and placebo controlled clinical trials into our meta-analysis. We extracted the baseline and outcomes from the clinical trials and evaluated its risks of bias. Biological markers were measured by amyloid beta (A) accumulation, and cognitive outcomes were measured by the Wechsler Memory Scale - Fourth Edition (WMS-IV) and Mini Mental State Exam (MMSE). For one study, the WMS-IV was used to measure cognitive outcome. The other study measured cognitive outcome with the MMSE. Biological markers were measured by A accumulation in one study and with [11C]PIB tracer in another. There was no significant difference between the placebo and experimental group after the treatment period.