Postoperative cognitive dysfunction, Alzheimer's disease, and anesthesia

Although aging itself is not a disease, there are many comorbidities that become more common with aging. Heart disease, cancer, and other chronic illnesses are either more common or more severe in aging patients. Approximately 5.5 million people in the United States have Alzheimer's disease (AD), with the principal risk factor being age. It is estimated that the incidence of AD diagnosis doubles every 5 years after the age of 65. Therefore, as the population ages, the impact of AD on the healthcare landscape will increase. Understanding how to manage patients with AD is critical as we begin to care for more elderly patients in the perioperative period. In addition to their other health considerations, aging surgical patients are increasingly more likely to have pre-existing AD or be at risk for developing AD. There is growing interest to determine how anesthesia affects the development or progression of AD. Similarly, a best practice for the anesthetic management of patients with AD is not yet defined. Finally, the relationship between AD and susceptibility to or exacerbation of postoperative cognitive dysfunction (POCD) is not well understood. In this review, we will discuss both the clinical and the preclinical data related to anesthesia and AD, describe the overlapping pathophysiology of neurodegeneration and provide some insight into the anesthetic care of patients with AD.