Postoperative Delirium (POD)NCT07859488
Perioperative Biomarkers and Postoperative Delirium in Older Adults Undergoing Abdominal Cancer Surgery
An observational study of Postoperative Delirium (POD) and Abdominal Neoplasms, run by Fatma Cigdem Ozakin at 1 site in Turkey (Türkiye).
Trial summary
This prospective observational cohort study aims to investigate the relationship between perioperative endogenous melatonin levels and postoperative delirium in patients aged 65 years or older undergoing elective abdominal cancer surgery. Read more about this study
- Who is it for?
- Ages 65 years and older
- Conditions the study is for
- Postoperative Delirium (POD), Abdominal Neoplasms
- What is being tested?
- Perioperative Biomarker Assessment and Confusion Assessment Method (CAM)
- How many people
- 100 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Sep 2026to 6 Sep 2027
- Phase
- Observational
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 65 years and older
- All sexes
- No healthy volunteers
- Older adult
Study population: The study population will consist of patients aged 65 years or older who are scheduled for elective abdominal surgery for malignancy at Bakirkoy Dr. Sadi Konuk Research and Training Hospital and who meet the study eligibility criteria and provide written informed consent.
Who may be able to join
- Age 65 years or older.
- Scheduled for elective abdominal surgery for malignancy.
- American Society of Anesthesiologists (ASA) physical status II or III.
- Surgery planned under general anesthesia.
- Eligible for thoracic epidural analgesia without contraindications to epidural catheter placement.
- Provision of written informed consent.
Who cannot join
- Preoperative dementia, Alzheimer disease, Parkinson disease, other known neurodegenerative disease, or a history of preoperative cognitive impairment.
- Emergency surgery.
- Contraindication to epidural analgesia or refusal of epidural catheter placement.
- Chronic use of corticosteroids, melatonin preparations, or medications affecting the serotonergic system, including selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, monoamine oxidase inhibitors, or tricyclic antidepressants.
- Parenteral or high-dose oral vitamin B12 treatment within the previous 3 months.
- Diagnosis of pernicious anemia.
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- Communication impairment preventing delirium assessment.
- Advanced liver or kidney failure.
- Intraoperative mean arterial pressure below 65 mmHg.
- Surgical duration longer than 240 minutes.
- Refusal to participate in the study.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site, 1 recruiting
- Recruiting
Bakırköy Dr. Sadi Konuk Training and Research Hospital
Istanbul, Istanbul, 34147
Fatma Çiğdem Özakın, MD, +905464168250, f.cigdemulus@gmail.com
Fidan Aygün, MD
About this study
Official title: Perioperative Melatonin and Other Neuroinflammatory Biomarkers for Predicting Postoperative Delirium in Older Adults Undergoing Elective Abdominal Cancer Surgery
This prospective observational cohort study aims to investigate the relationship between perioperative endogenous melatonin levels and postoperative delirium in patients aged 65 years or older undergoing elective abdominal cancer surgery. The study will also evaluate serotonin, kynurenine, kynurenic acid, and vitamin B12 as potential biomarkers associated with postoperative delirium.
Participants will undergo routine standardized general anesthesia and thoracic epidural analgesia. Venous blood samples will be obtained preoperatively and on postoperative day 3. In participants who develop delirium, an additional blood sample will be obtained as soon as possible after delirium is detected. Postoperative delirium will be assessed using the Confusion Assessment Method (CAM) on postoperative days 1, 3, and 5. No experimental drug or additional therapeutic intervention will be administered as part of the study.
Read the detailed description
Postoperative delirium is an acute neurocognitive disorder that occurs frequently in older patients after major surgery. Neuroinflammation, alterations in neurotransmitter metabolism, oxidative stress, and disruption of circadian rhythm have been proposed as contributing mechanisms.
The primary objective of this prospective observational cohort study is to evaluate the relationship between perioperative endogenous melatonin levels and the development of postoperative delirium in patients aged 65 years or older undergoing elective abdominal surgery for malignancy. Secondary objectives include evaluation of serotonin, kynurenine, kynurenic acid, and vitamin B12 levels in relation to postoperative delirium.
Eligible participants will receive the routine standardized anesthesia and analgesia protocol used at the study center, including general anesthesia and thoracic epidural analgesia. No experimental drug or treatment will be administered.
Venous blood samples will be obtained during the preoperative period for measurement of melatonin, serotonin, kynurenine, kynurenic acid, and vitamin B12. These biomarkers will be measured again on postoperative day 3. In participants who develop postoperative delirium, an additional sample will be obtained as soon as possible after delirium is detected.
Intraoperative hemodynamic parameters, vasopressor requirements, cerebral oxygenation measured by near-infrared spectroscopy, depth of anesthesia measured by Bispectral Index, estimated blood loss, blood product transfusion, anesthesia duration, and surgical duration will also be recorded.
Postoperative delirium will be prospectively evaluated using the Confusion Assessment Method on postoperative days 1, 3, and 5. Participants will subsequently be classified as having or not having postoperative delirium, and perioperative biomarker levels and clinical variables will be compared between these groups.
- Conditions
- Postoperative Delirium (POD), Abdominal Neoplasms
- Being tested
- Perioperative Biomarker Assessment, Confusion Assessment Method (CAM)
- Keywords
- Postoperative delirium, Melatonin, Serotonin, Kynurenine, Kynurenic acid, Vitamin B12, Neuroinflammation, Geriatric surgery, Abdominal cancer surgery, Confusion Assessment Method
- Medical subject headings
- Emergence Delirium, Abdominal Neoplasms, Neuroinflammatory Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Perioperative Biomarker AssessmentDiagnostic test
Venous blood samples will be obtained preoperatively and on postoperative day 3 for measurement of melatonin, serotonin, kynurenine, kynurenic acid, and vitamin B12. In participants who develop postoperative delirium, an additional blood sample will be obtained as soon as possible after delirium is detected. Biomarker measurements will not be used to determine clinical treatment.
Confusion Assessment Method (CAM)Diagnostic test
The Confusion Assessment Method will be used to assess delirium preoperatively and on postoperative days 1, 3, and 5. Postoperative delirium will be considered present if at least one postoperative CAM assessment is positive.
| Study group | Role | What they receive |
|---|---|---|
| Older Adults Undergoing Elective Abdominal Cancer Surgery | Patients aged 65 years or older undergoing elective abdominal surgery for malignancy under general anesthesia with thoracic epidural analgesia. All participants will be prospectively followed for postoperative delirium through postoperative day 5. Participants will not be assigned to treatment groups. For analysis, participants will be classified according to whether postoperative delirium develops based on CAM assessments. Receives: Diagnostic Test: Perioperative Biomarker Assessment; Diagnostic Test: Confusion Assessment Method (CAM) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Serum Melatonin Concentration From Preoperative Baseline to Postoperative Day 3 According to Postoperative Delirium Status
Serum melatonin concentration will be measured preoperatively and on postoperative day 3. For each participant, the change in melatonin concentration will be calculated as the postoperative day 3 value minus the preoperative value and reported in pg/mL. Participants will be classified as having postoperative delirium if at least one CAM assessment on postoperative days 1, 3, or 5 is positive. The change in melatonin concentration will be compared between participants with and without postoperative delirium.
Measured: Preoperative baseline to postoperative day 3; postoperative delirium status assessed through postoperative day 5
Number of Participants With Postoperative Delirium Assessed by the Confusion Assessment Method
Postoperative delirium will be assessed using the Confusion Assessment Method (CAM) on postoperative days 1, 3, and 5. A participant will be classified as having postoperative delirium if any of these postoperative CAM assessments is positive. According to the CAM algorithm, delirium is present when acute onset and fluctuating course and inattention are present together with either disorganized thinking or an altered level of consciousness. The number and percentage of participants with postoperative delirium will be reported.
Measured: Postoperative day 1 through postoperative day 5
Secondary outcomes (3)
Change in Serum Serotonin Concentration From Preoperative Baseline to Postoperative Day 3 According to Postoperative Delirium Status
Serum serotonin concentration will be measured preoperatively and on postoperative day 3. The change from the preoperative value will be calculated for each participant and compared between participants with and without postoperative delirium.
Measured: Preoperative baseline to postoperative day 3
Change in Serum Kynurenine Concentration From Preoperative Baseline to Postoperative Day 3 According to Postoperative Delirium Status
Serum kynurenine concentration will be measured preoperatively and on postoperative day 3. The change from the preoperative value will be calculated for each participant and compared between participants with and without postoperative delirium.
Measured: Preoperative baseline to postoperative day 3
Change in Serum Kynurenic Acid Concentration From Preoperative Baseline to Postoperative Day 3 According to Postoperative Delirium Status
Serum kynurenic acid concentration will be measured preoperatively and on postoperative day 3. The change from the preoperative value will be calculated for each participant and compared between participants with and without postoperative delirium.
Measured: Preoperative baseline to postoperative day 3
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Oct 2026
- Study start1 Sep 2026
- Primary completion1 Sep 2027 (estimated)
- Study completion6 Sep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (3)Papers the sponsor has linked to this study.
- Other trials for Postoperative Delirium (POD)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Fatma Cigdem Ozakin
- Sponsor type
- Other government
- Responsible party
- Sponsor-investigator, Fatma Cigdem Ozakin, Bakirkoy Dr. Sadi Konuk Research and Training Hospital
- Investigators
- Fatma Çiğdem Özakın, MD, Study director, Bakirkoy Dr. Sadi Konuk Research and Training Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07859488
- Sponsor's protocol ID
- 2026-280
- Status last verified
- Sep 2026
- First submitted
- 30 Sep 2026
- Last updated
- 5 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Elbakry AA, El-Desoky IM, Saafan AG, Elsersy HE. The impact of melatonin on postoperative delirium in geriatric patients after colorectal surgery: a randomized placebo-controlled trial. Minerva Anestesiol. 2024 Jun;90(6):509-519. doi: 10.23736/S0375-9393.24.17888-1.
PubMed 38869264Phing AH, Makpol S, Nasaruddin ML, Wan Zaidi WA, Ahmad NS, Embong H. Altered Tryptophan-Kynurenine Pathway in Delirium: A Review of the Current Literature. Int J Mol Sci. 2023 Mar 15;24(6):5580. doi: 10.3390/ijms24065580.
PubMed 36982655Inouye SK, Westendorp RG, Saczynski JS. Delirium in elderly people. Lancet. 2014 Mar 8;383(9920):911-22. doi: 10.1016/S0140-6736(13)60688-1. Epub 2013 Aug 28.
PubMed 23992774