LAUSR

ABSTRACT Background: Cognitive decline is an important complication of joint replacement surgeries in senior people. Methods: We determined incidence rates of dementia diagnosis following endoprosthetic joint replacement surgery (upper and lower extremities). The observation period covered up to 28 quarters using German claims data comprising 154,604 cases 65 years and older. Effects were controlled for cerebrovascular and vascular risk factors, age, sex, the presence of a diagnosis of delirium, and regular prescription of sedative or analgesic drugs (SAD). Results: The rate of incident dementia diagnoses in people without joint replacement surgery was 21.34 per 1,000 person years, compared with 80.76 incident cases when joint replacement surgery was conducted during the quarter of the incident dementia diagnosis; rates declined to 21.77 incident cases 7 and more quarters after joint replacement surgery had taken place. This pattern was maintained when controlling for delirium diagnosis and regular prescription of SAD. Among 10,563 patients with at least one joint replacement surgery, patients with a diagnosis of delirium in the quarter of the surgery were at increased risk of a dementia diagnosis compared to patients without such a diagnosis (HR=2.00, p < 0.001). Conclusion: In people surviving the high-risk phase for dementia immediately after surgery, long-term risk of dementia may reach the level of those without surgery. These findings encourage consequent perioperative management to reduce the risk of dementia as well as prospective studies of potentially beneficial effects of joint replacement surgery on mid- to long-term recovery of mobility and cognition in geriatric patients.