Association of neurocognitive disorders with morbidity and mortality in older adults undergoing major surgery in the USA: a retrospective, population-based, cohort study.

Background: Neurocognitive disorders become increasingly common as patients age, and increasing numbers of surgical interventions are done on older patients. The aim of this study was to understand the clinical characteristics and outcomes of surgical patients with neurocognitive disorders in the USA in order to guide future targeted interventions for better care.
Methods: This retrospective cohort study used claims data for US Medicare beneficiaries aged 65 years and older with a record of inpatient admission for a major diagnostic or therapeutic surgical procedure between Jan 1, 2017, and Dec 31, 2018. Data were retrieved through a data use agreement between Dartmouth Hitchcock Medical Center and US Centers for Medicare and Medicaid Services via the Research Data Assistance Center. The exposure of interest was the presence of a pre-existing neurocognitive disorder as defined by diagnostic code within 3 years of index hospital admission. The primary outcome was mortality at 30 days, 90 days, and 365 days from date of surgery among all patients with available data.
Findings: Among 5 263 264 Medicare patients who underwent a major surgical procedure, 767 830 (14·59%) had a pre-existing neurocognitive disorder and 4 495 434 (85·41%) had no pre-existing neurocognitive disorder. Adjusting for demographic factors and comorbidities, patients with a neurocognitive disorder had higher 30-day (hazard ratio 1·24 [95% CI 1·23-1·25]; p<0·0001), 90-day (1·25 [1·24-1·26]; p<0·0001), and 365-day mortality (1·25 [1·25-1·26]; p<0·0001) compared with patients without a neurocognitive disorder.
Interpretation: Our findings suggest that the presence of a neurocognitive disorder is independently associated with an increased risk of mortality. Identification of a neurocognitive disorder before surgery can help clinicians to better disclose risks and plan for patient care after hospital discharge.
Funding: Department of Anesthesiology and Perioperative Medicine at Dartmouth Hitchcock Medical Center.
Competing Interests: Declaration of interests AB reports compensation from the American College of Surgeons for her previous work related to the Geriatric Surgical Verification programme; funding from the Susan and Levy Health Care Delivery Incubator at Dartmouth for implementation of a geriatric surgery programme; and speaker's fees for lectures related to geriatric surgery. ELW reports research funding from the US National Institutes of Health (National Institute on Aging). SS reports research funding from the US National Institutes of Health (National Institute on Aging and National Institute of General Medical Sciences). SGD reports payment for expert testimony; is a Director of the American Board of Anesthesiology; and is Chair of the American Society of Anesthesiology Brain Health Subcommittee. ATA is a member of the Multicenter Perioperative Outcomes Group brain health working group; is co-inventor on several medical device patent applications (none related to brain health or neurocognitive disorders); has previously started a medical device company directed towards developing sensor-enhanced needles; is co-founder of a non-profit medical innovation group at Dartmouth Health; and is an adviser to Simbex Corporation, a medical technology development company, but receives no remuneration for this work and has not consulted on any technologies related to the subject matter of this manuscript. All other authors declare no competing interests.
(Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)