Development and validation of a new drug-focused predictive risk score for postoperative delirium in orthopaedic and trauma surgery patients

BMC Geriatr. 2024 May 13;24(1):422. doi: 10.1186/s12877-024-05005-1.

Abstract

Background: Postoperative delirium (POD) is the most common complication following surgery in elderly patients. During pharmacist-led medication reconciliation (PhMR), a predictive risk score considering delirium risk-increasing drugs and other available risk factors could help to identify risk patients.

Methods: Orthopaedic and trauma surgery patients aged ≥ 18 years with PhMR were included in a retrospective observational single-centre study 03/2022-10/2022. The study cohort was randomly split into a development and a validation cohort (6:4 ratio). POD was assessed through the 4 A's test (4AT), delirium diagnosis, and chart review. Potential risk factors available at PhMR were tested via univariable analysis. Significant variables were added to a multivariable logistic regression model. Based on the regression coefficients, a risk score for POD including delirium risk-increasing drugs (DRD score) was established.

Results: POD occurred in 42/328 (12.8%) and 30/218 (13.8%) patients in the development and validation cohorts, respectively. Of the seven evaluated risk factors, four were ultimately tested in a multivariable logistic regression model. The final DRD score included age (66-75 years, 2 points; > 75 years, 3 points), renal impairment (eGFR < 60 ml/min/1.73m2, 1 point), anticholinergic burden (ACB-score ≥ 3, 1 point), and delirium risk-increasing drugs (n ≥ 2; 2 points). Patients with ≥ 4 points were classified as having a high risk for POD. The areas under the receiver operating characteristic curve of the risk score model were 0.89 and 0.81 for the development and the validation cohorts, respectively.

Conclusion: The DRD score is a predictive risk score assessable during PhMR and can identify patients at risk for POD. Specific preventive measures concerning drug therapy safety and non-pharmacological actions should be implemented for identified risk patients.

Keywords: Geriatrics; Medication Safety; Postoperative delirium; Screening tools.

Publication types

  • Observational Study
  • Validation Study

MeSH terms

  • Acute Care Surgery
  • Aged
  • Aged, 80 and over
  • Delirium* / diagnosis
  • Female
  • Humans
  • Male
  • Medication Reconciliation / methods
  • Middle Aged
  • Orthopedic Procedures* / adverse effects
  • Orthopedic Procedures* / methods
  • Postoperative Complications* / diagnosis
  • Postoperative Complications* / epidemiology
  • Postoperative Complications* / prevention & control
  • Retrospective Studies
  • Risk Assessment / methods
  • Risk Factors
  • Wounds and Injuries / surgery