# Incidence and factors associated with postoperative delirium after primary total joint arthroplasty in older adults: a systematic review and meta-analysis

## TL;DR

This study finds that 13.6% of older adults experience delirium after joint replacement surgery, and identifies risk factors like age and chronic diseases.

## Contribution

The study provides a systematic review and meta-analysis of postoperative delirium incidence and risk factors in older adults undergoing total joint arthroplasty.

## Key findings

- The pooled incidence of postoperative delirium after TJA in older adults is 13.6%.
- Advanced age, chronic diseases, and certain medical conditions are associated with increased delirium risk.
- Higher educational attainment is a protective factor against postoperative delirium.

## Abstract

The proportion of older adults undergoing total joint arthroplasty (TJA) is increasing annually. Postoperative delirium (POD) is a common and serious complication among older adults after surgery. However, the incidence and factors associated with POD following primary TJA in this population remain unclear.

This study aimed to assess the incidence of delirium after primary TJA in older adults and to identify factors associated with POD through a meta-analytic approach.

A systematic literature search was performed in PubMed, Embase, Web of Science, and the Cochrane Library for studies published from inception to June 2025. Observational studies reporting POD incidence following TJA, including total hip arthroplasty and total knee arthroplasty in older adults (aged ≥60 years), were included. Pooled incidence rates and factors associated with POD were estimated using a random-effects model.

After applying the inclusion and exclusion criteria, 35 studies involving 29,311 older adults undergoing TJA were included. The pooled POD incidence was 13.6% (95% CI, 12.2–15.0%), with substantial heterogeneity across studies. Advanced age, sleep apnea, hypertension, diabetes mellitus, coronary artery disease, stroke, chronic obstructive pulmonary disease, renal disease, solid tumors, dementia, Parkinson’s disease, psychiatric disorders, ASA class III/IV, substance use history, and blood transfusion were associated with increased POD risk. Conversely, higher educational attainment was identified as a protective factor.

This study systematically reported POD incidence among older adults undergoing TJA and identified factors associated with POD These findings provide evidence to optimize perioperative management and develop prevention strategies for POD in this population.

This study was registered in INPLASY platform (number: INPLASY202570015).