New postoperative depression links to higher dementia risk

In a nationwide cohort of Korean adults undergoing major cardiac or gastrointestinal surgery, researchers evaluated whether new postoperative depression is linked to subsequent dementia. The preprint analyzed 424,637 patients without a history of depression or major neurological disorders between 2002 and 2022. Postoperative depression was defined as a new diagnosis paired with an antidepressant prescription within one year after surgery. Patients alive and dementia-free at day 365 entered a landmark analysis and were tracked across postoperative years one to six. Overall, 7,633 patients developed postoperative depression. Researchers matched these individuals 1:3 with 22,899 controls based on age, sex, and income. During follow-up of the 30,532 matched participants, 786 incident dementia cases occurred, demonstrating an association with postoperative depression.