Abstract
BACKGROUND: Alzheimer disease (AD) entails a long-term progressive decline in the cognitive ability to think and remember, and it has become a major concern for patients receiving surgery and anesthesia. However, studies investigating the relationship between general anesthesia and AD have yielded inconsistent results. Therefore, we plan to perform a systematic review and meta-analysis to determine the relationship between general anesthesia and AD, and to verify whether general anesthesia is an independent risk factor for AD. METHODS: A systematic and comprehensive search will be performed using MEDLINE, EMBASE, and Google scholar from their inception to August 2017. Peer-reviewed cohort and case-control studies including nested case-control studies reporting the relationship between general anesthesia and AD will be eligible for inclusion. The quality of included studies will be assessed using the Newcastle-Ottawa scale. Heterogeneity of estimates across studies as well as publication bias will be assessed. This systematic review and meta-analysis will be performed according to the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines and reported according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines. All statistical analyses will be conducted using the Stata SE version 15.0. RESULTS: The results of this systematic review and meta-analysis will be published in a peer-reviewed journal. CONCLUSION: Our study will provide the evidence for the relationship between general anesthesia and dementia. The review will benefit patients and anesthesiologists, surgeons, and policymakers. ETHICS AND DISSEMINATION: Ethical approval and informed consent are not required, as the study will be a literature review and will not involve direct contact with patients or alterations to patient care. TRIAL REGISTRATION: The protocol for this review has been registered in the PROSPERO network (registration number: CRD42017073790).