TOPLINE

Older adults who developed delirium after surgery had more rehospitalizations and experienced lasting decline in cognition. Rehospitalizations, an indicator of illness and frailty, were linked to decline in cognition but did not explain the effect of delirium.

METHODOLOGY

• Researchers used data from a prospective cohort to assess whether rehospitalizations mediated the link between delirium after surgery and long-term cognitive decline.
• They included 560 older adults (mean age, 76.7 years; 58% women) who were scheduled to undergo major elective surgery at two Boston hospitals between 2010 and 2013.
• Delirium was assessed daily during the initial hospital stay, and information on rehospitalizations was retrieved from reports, claims data, and medical records.
• Changes in cognition were measured over 60 months using a composite score for general cognitive performance derived from multiple neuropsychological tests. Scores were adjusted using a nonsurgical comparison group. 

TAKEAWAY

• A total of 134 participants (24%) developed delirium after surgery. Participants who developed delirium had a 42% higher rate of rehospitalizations than those who did not.
• Each rehospitalization was associated with a decline of 0.19 units in the cognition score per year, and delirium was associated with a decline of 0.33 units per year.
• Delirium remained associated with long-term cognitive decline, even after adjusting for rehospitalizations. Rehospitalizations did not mediate the association.

IN PRACTICE

“[The] findings highlight the importance of implementing delirium prevention strategies as well as minimizing rehospitalizations in older adults,” the researchers wrote. “Postoperative delirium should be regarded as a complication with the potential for long-term consequences. An episode that seems to resolve during hospitalization may still matter years later,” experts wrote in an invited commentary.

SOURCE

The study was led by Tammy T. Hshieh, MD, MPH, of Harvard Medical School in Boston, and Zachary J. Kunicki, PhD, MS, MPH, of Warren Alpert Medical School of Brown University in Providence, Rhode Island. It was published online on June 8 in JAMA Internal Medicine along with an invited commentary written by Thiago J. Avelino-Silva, MD, PhD, and Alexander K. Smith, MD, MS, MPH, both of the Division of Geriatrics, Department of Medicine, University of California, San Francisco, and the Laboratório de Investigação Médica em Envelhecimento (LIM-66), Serviço de Geriatria, Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de São Paulo, Brazil.

LIMITATIONS

Most participants were White, well educated, and had orthopedic surgery. The study lost 21% of participants by 60 months, including 14% who died. Researchers lacked data on new episodes of delirium during follow-up.

DISCLOSURES

This study received support from grants from the National Institute on Aging. One author reported holding the Milton and Shirley F. Levy Family Chair at Hebrew Senior Life/Harvard Medical School. No conflicts of interest were reported.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.