Perioperative medicine & outcomes
Association between low Bispectral Index™ values during anesthesia maintenance and one-year mortality in older patients with different comorbidities: a retrospective cohort study
Main finding · 1-year mortality per cumulative duration of BIS < 40Result — go to the resultAdjusted hazard ratio 1.07 95% CI 0.99–1.15Authors' conclusion
In this retrospective cohort study of 5,927 older patients, the cumulative duration of BIS < 40 was not significantly associated with 1-year mortality, especially in patients with multimorbidity.
Study context
- Population
- Older patients (≥ 65 yr) undergoing elective noncardiac surgery under GA with BIS monitoring, February 2015 to February 2022
- Participants
- 5,927 patients
- Exposure
- Cumulative duration of BIS < 40 and 1-year mortality
- Charlson comorbidity index (CCI) ≥ 3n = 2,234
- CCI < 3n = 3,693reference
- Outcome
- Postoperative 1-year mortality
- Follow-up
- 1 year
Methodological detailsexploratory subgroup and interaction analyses
- Exploratory subgroup and interaction analyses
Main finding
As reported in the abstract
1-year mortality per cumulative duration of BIS < 40
Adjusted hazard ratio
1.07
95% CI 0.99–1.15
P = 0.08
Cumulative duration of BIS < 40
aHR 1.07 (95% CI 0.99–1.15); P = 0.08
Per cumulative duration of BIS < 40, as printed
- Deaths within 1 year (all patients)
- 588/5,927 (10%)
Observational data: associations, not effects.
Further findings
| Outcome | aHR (95% CI) | |
|---|---|---|
| 1-year mortality per cumulative duration of BIS < 40 (multimorbidity subgroup)Patients with multimorbidity · exploratory subgroup analysis | 1.06 (0.96–1.16) | |
| 0.512Adjusted hazard ratio (log scale) |
Original publication
Association between low Bispectral Index™ values during anesthesia maintenance and one-year mortality in older patients with different comorbidities: a retrospective cohort study. Can J Anaesth. Published 17 June 2025. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →