Preoperative Lymphocyte-to-Monocyte Ratio and Postoperative Delirium by Frailty Status in Older Surgical Patients

Association Between Preoperative Lymphocyte-to-Monocyte Ratio and Postoperative Delirium According to Frailty Status in Older Surgical Patients: A Prospective Cohort Study

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT07322744

Enrollment

6475

Registered

2026-01-07

Start date

2020-04-01

Completion date

2023-12-30

Last updated

2026-01-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Frailty at Older Adults, Lymphocyte, Postoperative Delirium (POD)

Keywords

postoperative delirium, frailty, older surgical patients, lymphocyte-to-monocyte ratio

Brief summary

Both frailty and a reduced preoperative lymphocyte-to-monocyte ratio (LMR) are known risk factors for postoperative delirium (POD). However, whether the relationship between LMR and POD varies by frailty status remains unclear. This study aimed to evaluate the frailty-stratified association between preoperative LMR and POD in older surgical patients.

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

RETROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

65 Years to No maximum

Healthy volunteers

Inclusion criteria

* Aged ≥65 years; * Underwent elective noncardiac, nonneurosurgical procedures; * Completed the preoperative health and functional status questionnaire.

Exclusion criteria

* Severe dementia, language disorders, significant hearing or visual impairments, or coma; * Cognitive function below the Mini-Mental State Examination thresholds (\<18 for illiterate individuals, \<21 for individuals with primary education, and \<25 for individuals with secondary education or higher); * Surgery performed under local anesthesia or monitored anesthesia care; * Missing lymphocyte or monocyte count data; * Missing postoperative delirium assessment; * Incomplete preoperative FRAIL scale evaluation; * Missing data for more than 20% of covariates.

Design outcomes

Primary

Measure	Time frame	Description
The primary outcome was the occurrence of postoperative delirium (POD).	POD assessment was performed twice daily for up to seven consecutive postoperative days or until hospital discharge, whichever occurred first.	The primary outcome was the occurrence of POD, evaluated by trained researchers using the 3-Minute Diagnostic Interview for Confusion Assessment Method (3D-CAM).

Countries

China

Outcome results