Postoperative Delirium Predicts Sustained Functional Decline in Older Adults After Cardiac Surgery: A 5-Year Prospective Cohort Study

Intro:

Postoperative delirium (POD) affects 15-50% of older cardiac surgery patients, yet its long-term functional consequences remain poorly characterised. This study examines the association between POD and 5-year trajectories of disability using prospectively collected Barthel Index data.

Methods:

We analysed 135 patients aged ≥60 undergoing elective CABG±valvular surgery at a UK tertiary centre (2017-2023). POD was identified through daily Postoperative Morbidity Survey (POMS) assessments. Functional status was measured via Barthel Index (0-20) preoperatively and at discharge and at 6 weeks, 6 months, and 5 years postoperatively. Frailty was measured via the Edmonton Frailty Scale (EFS), and baseline cognition was measured via a MoCA.

Results:

Of 135 patients, 42 (31.1%) developed POD. Delirious patients exhibited significantly greater functional decline: median Barthel scores were 3 points lower at discharge (17 vs 20, p=0.01) and 2 points lower at 5 years (18 vs 20, p=0.03) compared to non-delirious patients. This decline was most pronounced in frail patients (EFS≥5) with POD, who showed a 6-point Barthel decrease versus 1-point in non-frail controls (p<0.001). POD independently predicted care facility discharge (OR 3.2, 95%CI 1.5-6.8) and was associated with 2.5-fold higher 5-year mortality (HR 2.5, 95%CI 1.3-4.8).

Conclusions:

POD is a strong predictor of persistent disability and mortality after cardiac surgery, particularly in frail patients. These findings underscore the need for preoperative delirium risk stratification and post-delirium rehabilitation programs to preserve long-term independence in older surgical patients.