Post-operative delirium is associated with increased 5-year mortality

https://doi.org/10.1016/j.amjsurg.2017.08.034Get rights and content

Abstract

Background

Post-operative delirium is associated with increased short term morbidity and mortality. Limited data exists on long term outcomes for older adults with postoperative delirium. We hypothesize that postoperative delirium is associated with increased 5-year mortality.

Methods

Patients ≥50 years undergoing elective operations with planned intensive care unit (ICU) admissions were prospectively enrolled. The Confusion Assessment Method ICU (CAM-ICU) was used to diagnose delirium. The primary outcome variable was 5-year mortality.

Results

172 patients were enrolled with an average age of 64 years. The overall incidence of delirium was 44% (75/172). At 5-years post-operatively, mortality was higher (59%, 41/70) in patients with delirium compared to patients without delirium (13%, 12/94, p < 0.001). These results remained true after multivariable risk adjustment, showing the odds of five year mortality following delirium were 7.35 fold greater (95% CI: 1.49–36.18).

Conclusions

Postoperative delirium is associated with increased long term mortality.

Introduction

Around 40% of inpatient surgeries in the United States are performed in patients 65 years and older, a number that is expected to increase as the population continues to age.1 Post-operative complications increase with advancing age.2 Post-operative delirium is the most common complication of major surgery in older patients and remains a life threatening problem.3 Risk factors for the development of post-operative delirium include dementia, functional dependence, multi-morbidity and malnutrition.4, 5

Our group has reported on the risk factors for postoperative delirium and six-month mortality associated with the motor subtypes of postoperative delirium.6 Postoperative delirium occurred in 44% of patients in our cohort.7 There is a gap in the literature in that the long-term outcomes in patients who develop postoperative delirium is not well understood. The purpose of this study was to compare 5-year postoperative mortality in patients who did and did not develop postoperative delirium. We hypothesized that post-operative delirium would be associated with increased postoperative 5-year mortality.

Section snippets

Methods

This prospective study was performed at the Denver Veterans Affairs Medical Center. Patients 50 years and older undergoing elective major abdominal general, orthopaedic, urologic, or vascular surgery with a planned ICU admission were enrolled between December 2007 and December 2011. Exclusion criteria included patients undergoing intracranial surgery, vision or hearing impairment, patients who could not speak English, and patients who could not provide informed consent. Regulatory approval was

Results

One hundred and seventy two patients were enrolled during the five year study period. Mean patient age was 64 ± 8 years and 97% were male. Seventy-five patients experienced delirium during their hospitalization (44%). Five-year follow-up data was available for 164 patients (95%). Overall 5-year mortality was 32% (53/164). Five-year mortality was 59% (41/70) in patients with delirium compared to 13% (12/94) in patients without delirium (p < 0.001).

Several important differences were noted on

Discussion

Delirium in the postoperative setting is associated with increased morbidity and mortality. This study specifically investigated 5-year mortality in patients with and without postoperative delirium. This study is unique in that it is the first study to examine long-term mortality associated with postoperative delirium. While delirium has not consistently been thought of as a post-operative complication,16 this study clearly demonstrates the lasting effects of post-operative delirium: A seven

Conclusions

Postoperative delirium is independently associated with a seven fold increase in 5 year mortality. Delirium in the immediate postoperative period has lasting consequences; likely because it represents underlying depleted physiologic reserves in patients who develop postoperative delirium.

Funding sources

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Acknowledgements

None.

References (24)

  • A. Dworkin et al.

    A simple too to predict development of delirium after elective surgery

    J Am Geriatr Soc

    (2016 Nov)
  • S. Borson et al.

    The Mini-Cog as a screen for dementia: validation in a population-based sample

    J Am Geriatr Soc

    (2003)
  • Cited by (73)

    View all citing articles on Scopus
    View full text