Because long-term cognitive decline can occur in some older adults after undergoing surgery, there has been some concern that exposure to anesthesia may be associated with increased dementia risk. It is therefore pleasing to report that data from the very large, long-running Mayo Clinic Study, the Rochester Epidemiology Project, has found that receiving general anesthesia for procedures after age 45 is not a risk factor for developing dementia.
http://www.eurekalert.org/pub_releases/2013-05/mc-nlb042913.php
[3409]
(Submitted). Anesthesia and Incident Dementia: A Population-Based, Nested, Case-Control Study.
Mayo Clinic Proceedings.