Prevalence of preoperative cognitive impairment in older surgical patients.: A systematic review and meta-analysis

J Clin Anesth. 2022 Feb;76:110574. doi: 10.1016/j.jclinane.2021.110574. Epub 2021 Nov 5.

Abstract

Study objective: Older surgical patients with cognitive impairment are at an increased risk for adverse perioperative outcomes, however the prevalence of preoperative cognitive impairment is not well-established within this population. The purpose of this review is to determine the pooled prevalence of preoperative cognitive impairment in older surgical patients.

Design: Systematic review and meta-analysis.

Setting: MEDLINE (Ovid), PubMed (non-MEDLINE records only), Embase, Cochrane Central, Cochrane Database of Systematic Reviews, PsycINFO, and EMCare Nursing for relevant articles from 1946 to April 2021.

Patients: Patients aged ≥60 years old undergoing surgery, and preoperative cognitive impairment assessed by validated cognitive assessment tools.

Interventions: Preoperative assessment.

Measurements: Primary outcomes were the pooled prevalence of preoperative cognitive impairment in older patients undergoing either elective (cardiac or non-cardiac) or emergency surgery.

Main results: Forty-eight studies (n = 42,498) were included. In elective non-cardiac surgeries, the pooled prevalence of unrecognized cognitive impairment was 37.0% (95% confidence interval [CI]: 30.0%, 45.0%) among 27,845 patients and diagnosed cognitive impairment was 18.0% (95% CI: 9.0%, 33.0%) among 11,676 patients. Within the elective non-cardiac surgery category, elective orthopedic surgery was analyzed. In this subcategory, the pooled prevalence of unrecognized cognitive impairment was 37.0% (95% CI: 26.0%, 49.0%) among 1117 patients, and diagnosed cognitive impairment was 17.0% (95% CI: 3.0%, 60.0%) among 6871 patients. In cardiac surgeries, the unrecognized cognitive impairment prevalence across 588 patients was 26.0% (95% CI: 15.0%, 42.0%). In emergency surgeries, the unrecognized cognitive impairment prevalence was 50.0% (95% CI: 35.0%, 65.0%) among 2389 patients.

Conclusions: A substantial number of surgical patients had unrecognized cognitive impairment. In elective non-cardiac and emergency surgeries, the pooled prevalence of unrecognized cognitive impairment was 37.0% and 50.0%. Preoperative cognitive screening warrants more attention for risk assessment and stratification.

Keywords: Cognitive impairment; Older patients; Preoperative assessment; Prevalence; Surgery; meta-analysis.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Aged
  • Cognitive Dysfunction* / diagnosis
  • Cognitive Dysfunction* / epidemiology
  • Cognitive Dysfunction* / etiology
  • Elective Surgical Procedures / adverse effects
  • Humans
  • Middle Aged
  • Prevalence
  • Risk Assessment