Elderly Patients Undergoing Surgery During Perioperative Period

Elderly Patients Undergoing Surgery During Perioperative Period: a Prospective Cohort Study

The elderly patients have poorer overall conditions and have lower tolerance to trauma, anesthesia, and surgery. Therefore, the incidence of postoperative complications is relatively higher. In non-cardiac surgeries, approximately 20% of elderly patients experience postoperative complications, and the incidence of postoperative delirium (POD) is 23.8%. This may lead to prolonged hospital stays, increased hospital costs, and affect prognosis and even mortality. The investigators plan to conduct a prospective cohort study by systematically collecting biological samples and clinical information of elderly patients during the perioperative period to explore the possible risk factors and pathogenesis of postoperative delirium and postoperative complications in elderly surgical patients, and to construct a risk prediction model for postoperative complications.

Study Overview

• Status: Recruiting
• Conditions: Postoperative Complications; Elderly; Postoperative Delirium (POD); Pathogenesis; Risk Prediction Model

• Study Type: Observational
• Enrollment (Estimated): 1200

Contacts and Locations

• Study Contact: Name: Ting Li MD. PhD; Phone Number: +86-135-8787-6896; Email: liting1021@aliyun.com

Study Locations

• China
  • Zhejiang
    • Wenzhou, Zhejiang, China, 325000
      • Recruiting
      • The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University
      • Contact: Ting Li MD.PhD; Phone Number: 0577-88002888; Email: liting1021@aliyun.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Surgical patients aged 65 or above or non-surgical subjects aged 65 or above

Description

Inclusion Criteria:

1) Surgical patients aged 65 or above or non-surgical subjects aged 65 or above. 2) Agree to participate in this study and sign the informed consent form.

Exclusion Criteria:

1）Refused to participate in the study.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Surgical patients aged 65 years or older; For the surgical group patients, questionnaires and scales measuring cognitive function, sleep quality, and quality of life were collected preoperatively, at 1-7 days post-operation, 30 days post-operation, and 1 year post-operation. During the operation, blood, cerebrospinal fluid, and other biological samples from the patients were also collected.
non-surgical subjects aged 65 years or older; For the non-surgical group patients, patients' basic information was collected, along with cognitive scales, sleep scales, and quality of life questionnaires.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of postoperative delirium (POD) within 7 days after surgery	POD is diagnosed daily using the Three-Minute Diagnostic Confusion Assessment Method (3D-CAM).	Preoperative, during the first 7 postoperative days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Days at home up to 30 days after surgery (DAH30)		up to 30 days after surgery
Length of hospitalization	Length of hospital stay are measured from the anesthesia starting day to the discharge day	till the day of discharge from hospital, an average of 7 days
Economic indicators	Hospitalization fees; -Preoperative fees; -Anesthesia fees; -Surgery fees; -Post-operative fees; -Post-discharge medical expenses.	during the entire trial, an average of 1 year.
The types of postoperative delirium	The type of delirium is assessed using the Richmond Agitation-Sedation Scale (RASS). The Richmond Agitation-Sedation Scale (RASS) is a 10-point scale ranging from -5 (unarousable) to +4 (combative). A score of +4 represents a combative state where the patient is violent and poses immediate danger, while a score of -5 indicates no response to any stimulus. Based on the RASS score, delirium can be categorized into three motoric subtypes: Hyperactive delirium: RASS scores consistently between +1 and +4. Hypoactive delirium: RASS scores consistently between 0 and -3. Mixed-type delirium: RASS scores that fluctuate between positive and negative values over the observation period.	Preoperative, during the first 7 postoperative days
The severity of postoperative delirium	The severity of postoperative delirium will be assessed using the Confusion Assessment Method-Severity scale (CAM-S).	Preoperative, during the first 7 postoperative days
The duration of postoperative delirium	Duration is defined as the number of days from the onset of delirium symptoms to symptom resolution or hospital discharge, whichever occurs first.	Preoperative, during the first 7 postoperative days
Postoperative neurocognitive dysfunction	Neurocognitive decline is assessed by comparing baseline to postoperative scores on: Mini-Mental State Examination (MMSE, 0-30, higher=better function), Montreal Cognitive Assessment (MoCA, 0-30, higher=better function); and five neuropsychological tests-Clock Drawing Test, (DST, 0-16, higher=better attention), Trail Making Test Parts A and B (TMT-A/B, seconds, lower=better), Boston Naming Test (BNT, 0-30, higher=better naming), Auditory Verbal Learning Test - Huashan version (AVLT-H delayed recall, 0-10, higher=better memory), and Clock Drawing Test (CDT, 0-10, higher=better visuospatial/executive function). Patient/caregiver reports are also collected.	preoperative baseline, within 7 days postoperatively, and at 1, 6, and 12 months postoperatively.
Acute pain	Using Visual Analogue Scale (VAS), 0-100, 0 means no pain, 100 means severe pain	Preoperative and 3 days postoperative.
Hospital Anxiety and Depression Scale (HADS) score	The Hospital Anxiety and Depression Scale (HADS) is used for assessment, with each subscale (anxiety or depression) scored from 0-21: "0-7: Non-case", "8-10: Doubtful case", "11-21: Definite case". Higher scores clearly indicate worse outcomes, i.e., more severe anxiety or depression symptoms.	preoperative, 5 days, 1 month, 6 months, and 1 year postoperative.
Activity of Daily Living	The Activities of Daily Living (ADL) are typically assessed using the Barthel Index. 0-100. A higher score indicates stronger independence: a score of 100 represents complete independence; a score of 61-99 suggests mild functional impairment with basic self-care ability; and a score of ≤40 indicates severe functional impairment, with significant or complete reliance on others for daily living.	preoperative, 5 days, 1 month, 6 months, and 1 year postoperative.
Sleep quality	Sleep quality is assessed using the Pittsburgh Sleep Quality Index (PSQI). The total score ranges from 0 to 21 points. A score greater than 7 (>7) is typically considered the clinical cutoff for poor sleep quality. A higher score indicates poorer sleep quality.	preoperative, 5 days, 1 month, 6 months, and 1 year postoperative.
The FRAIL Scale	The FRAIL (Fatigue, Resistance, Ambulation, Illnesses, and Loss of Weight) Scale ranges from 0 to 5. A score of 0 indicates robust/non-frail status, scores of 1-2 indicate pre-frail status, and scores of 3-5 indicate frail status.	preoperative, 5 days, 1 month, 6 months, and 1 year postoperative.
Quality of Life Score	using EQ-5D(Score of EuroQol Five Dimensions Questionnaire (EQ-5D)) to measure quality of life	preoperative, 1 month, 6 months, and 1 year postoperative.
Mortality	In-hospital mortality; 30-day postoperative mortality; 1-year postoperative mortality	During hospitalization, 1 month, 6 months, and 1 year postoperative.

Collaborators and Investigators

• Sponsor: Second Affiliated Hospital of Wenzhou Medical University
• Investigators: Principal Investigator: Ting Li, MD. PhD, Department of Anaesthesiology and Perioperative Medicine, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China

Study record dates

Study Major Dates

• Study Start (Actual): December 30, 2023
• Primary Completion (Estimated): December 30, 2030
• Study Completion (Estimated): December 30, 2030

Study Registration Dates

• First Submitted: December 11, 2025
• First Submitted That Met QC Criteria: December 31, 2025
• First Posted (Actual): January 2, 2026

Study Record Updates

• Last Update Posted (Actual): April 1, 2026
• Last Update Submitted That Met QC Criteria: March 26, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Cohort study; elderly; postoperative delirium
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Pathologic Processes; Confusion; Neurobehavioral Manifestations; Neurocognitive Disorders; Delirium; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Emergence Delirium; Postoperative Complications
• Other Study ID Numbers: SAHoWMU-CR2025-03-231

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Study protocol and statistical analysis plan.
• IPD Sharing Time Frame: Beginning 6 months after publication with no end date
• IPD Sharing Access Criteria: De-identified participant data underlying the findings will be made available upon reasonable request. Proposals for data access should be directed to the corresponding author (liting1021@aliyun.com).
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No