Association of Neighborhood Disadvantage With Postoperative Delirium After Cardiothoracic Surgery

Introduction: Neighborhood disadvantage is a potentially modifiable social determinant of health that may influence postoperative delirium (POD), a complication that disproportionately affects patients experiencing health disparities. However, neighborhood-level factors have not been widely studied in patients undergoing cardiothoracic surgery (CTS). This study evaluated the association between neighborhood disadvantage and development of POD.


Methods: In this retrospective cohort study, adults undergoing non-emergent CTS from 2017–2022 at 4 Pennsylvania hospitals were included. The Area Deprivation Index (ADI), a validated index reflecting 17 social determinants of health, determined neighborhood disadvantage. ADI state rankings (1–10, with more disadvantaged neighborhoods having higher scores) were linked to patients' residential Census Block Groups and grouped into ADI quintiles. A multivariable mixed-effects logistic regression with random hospital intercepts estimated the association between ADI quintiles and POD (positive CAM-ICU up to postoperative day 7), adjusting a priori for known preoperative risk factors (demographics, insurance, surgery type, comorbid diagnoses, and benzodiazepine use).


Results: Among 3,652 patients (mean age 63.9y, 68.4% male), mean ADI was 4.3 (±3.1). Compared to patients from the least disadvantaged neighborhoods, those from the most disadvantaged had 1.43 times higher odds of POD (95% CI: 1.12–1.83). Other risk factors included older age (OR 1.15 per 10 years, 95% CI: 1.06–1.25), Black race (OR 1.36, 95% CI: 1.02–1.82), aortic arch (OR 1.96, 95% CI: 1.52–2.54) or other aortic repairs (OR 2.59, 95% CI: 1.73–3.88), and mental health diagnoses (OR 1.41, 95% CI: 1.14–1.74). For example, 65-year-old Black females having an aortic arch repair with a mental health diagnosis (high risk clinical group) in the highest ADI quintile had an additional 9% greater predicted probability of POD compared to the same patient group in the lowest ADI quintile (95%CI, 0.42-0.64 vs 0.33-0.55 respectively).


Conclusions: The environment in which patients reside, in conjunction with their clinical presentation, are consequential health indicators. This study highlights the importance of considering neighborhood disadvantage as a risk factor for POD in non-emergent CTS patients.