Non-English Primary Language May Raise Risk of Delirium After Surgery, Study Finds

SAN ANTONIO — Older patients who primarily speak a language other than English may face a greater risk of developing delirium after surgery in U.S. hospitals, according to new research presented at the ANESTHESIOLOGY^® 2025 annual meeting. The study also found that a lower socioeconomic status further increased patients’ risk.

Postoperative delirium is a change in mental function that can cause confusion in up to 15% of surgical patients. In certain high-risk patients, such as those with hip fractures, the incidence can be even higher. It is a significant complication in older adults.

“Our study provides evidence that speaking a first or primary language other than English is an independent risk factor for delirium in U.S. patients undergoing anesthesia for surgery, even after ruling out other factors such as prior diagnoses of sleep apnea and type and duration of surgery,” said Maximilian Schaefer, M.D., Ph.D., senior author of the study, director of the Center for Anesthesia Excellence at Beth Israel Deaconess Medical Center and associate professor of anesthesia at Harvard Medical School, Boston. “We also found that delirium in these patients contributed to longer hospital stays, which can further delay recovery.”

U.S. health systems are providing care to increasingly diverse patient populations, including those whose first or primary language is not English. Before and after surgery, language barriers can contribute to confusion and agitation in patients, two factors that are associated with the development of postoperative delirium.

The study included 49,588 patients, age 60 or older, who had general anesthesia for non-cardiac and non-transplant surgery between 2011 and 2024 at a U.S. academic hospital. Researchers reviewed nursing and physician charts and used other assessment methods and tools to identify patients who developed delirium within seven days after surgery. Their analysis was adjusted for patient and procedural factors, including social determinants of health, such as socioeconomic status.

Among the 49,588 patients studied, 4,287 (8.7%) reported speaking a primary language other than English, with Spanish (28.5%) and Cantonese (13.5%) the most prevalent. Overall, 2,328 (4.7%) of the patients studied developed postoperative delirium — 2,093 whose primary language was English and 235 whose primary language was not English. Researchers concluded that patients whose primary language was not English were 23% more likely to develop delirium after surgery, than those whose primary language was English.  Additionally, this risk was 31% higher in non-English-speaking patients with lower estimated household incomes.

In patients who primarily spoke Spanish or other non-English languages, 151 of the 235 who developed delirium had interpreter support, but this did not reduce delirium risk.

“Most clinical interactions happen on the wards and in the ICU, where interpreter services aren’t always readily available — especially in the first days after surgery, when most delirium occurs,” said Dr. Schaefer. “While more research is needed on mechanisms, we suspect that greater confusion and fewer opportunities for verbal reorientation during this early postoperative phase may help explain the elevated delirium risk, even when interpreters are used.”

It is important that the full health care team is alerted to language barriers early during a patient’s perioperative care, so that accommodations can be made that extend beyond interpreter services, the authors note. For example, assigning health care providers who speak the patient’s language, ensuring family members are present to help with verbal reorientation, and seeing patients in the pre-admission testing clinic to identify risk factors for delirium can all help improve outcomes. However, the authors acknowledge that disparities in health care access and delivery are structural issues that need to be addressed beyond the individual patient level.

*** ANESTHESIOLOGY 2025 news releases may contain updated data that was not originally available at the time abstracts were submitted.

THE AMERICAN SOCIETY OF ANESTHESIOLOGISTS
Founded in 1905, the American Society of Anesthesiologists (ASA) is an educational, research and scientific society with more than 59,000 members organized to advance the medical practice of anesthesiology and secure its future. ASA is committed to ensuring anesthesiologists evaluate and supervise the medical care of all patients before, during and after surgery. ASA members also lead the care of critically ill patients in intensive care units, as well as treat pain in both acute and chronic settings.

For more information on the field of anesthesiology, visit the American Society of Anesthesiologists online at asahq.org. To learn more about how anesthesiologists help ensure patient safety, visit asahq.org/madeforthismoment. Join the #ANES25 conversation on social media. Follow ASA on Facebook, X, Instagram, Bluesky and LinkedIn.

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