UMIN-ICDS Clinical Trial

Public title

A study investigating the relationship between preoperative salivary components and postoperative infection and organ dysfunction

Acronym

Preoperative Saliva Study

Scientific Title

Association of Preoperative Salivary Metabolomic Profiles With Postoperative Sepsis and Organ Dysfunction: A Retrospective Cohort Study

Scientific Title:Acronym

SALIVA-POSTOP Study

Region

Japan

Condition

Postoperative infection, postoperative sepsis, and postoperative organ dysfunction in adult surgical patients

Classification by specialty

Surgery in general	Anesthesiology	Oral surgery
Emergency medicine	Intensive care medicine	Dental medicine

Classification by malignancy

Others

Genomic information

NO

Narrative objectives1

The primary objective of this study is to determine the association between preoperative salivary metabolomic profiles and postoperative sepsis defined according to Sepsis-3 criteria within 30 days after surgery by linking existing preoperative salivary metabolomic data with postoperative clinical data at Yamagata University Hospital.

The secondary objectives are to investigate the associations between preoperative salivary metabolomic profiles and postoperative infection, septic shock, postoperative SOFA score, organ-specific dysfunction, inflammatory responses, organ support therapies, ICU/HCU admission, length of hospital stay, and mortality.

Basic objectives2

Others

Basic objectives -Others

Exploration of associations between preoperative salivary metabolites and postoperative sepsis and organ dysfunction, and identification of potential biomarkers for postoperative risk stratification

Trial characteristics_1

Exploratory

Trial characteristics_2

Explanatory

Developmental phase

Not applicable

Primary outcomes

Postoperative sepsis meeting Sepsis-3 criteria within 30 days after surgery.

Postoperative sepsis is defined as a newly suspected postoperative infection accompanied by an acute increase of at least 2 points in the SOFA score from the pre-infection baseline, with the organ dysfunction judged by the investigators to be attributable to infection. Suspected infection will be determined based on antimicrobial treatment, microbiological cultures, imaging findings, diagnoses, and clinical course. Perioperative prophylactic antimicrobial administration will not be considered treatment for infection.

Key secondary outcomes

Postoperative infection within 30 days after surgery
Postoperative septic shock
Time from surgery to postoperative infection or sepsis
Source of infection and causative microorganisms
SOFA score at sepsis onset
Maximum SOFA score within 7 days after surgery
Change in SOFA score from the preoperative baseline
Organ-specific SOFA subscores for respiratory, coagulation, hepatic, cardiovascular, central nervous system, and renal dysfunction
SIRS and qSOFA
Postoperative changes in CRP, white blood cell count, lactate, creatinine, total bilirubin, platelet count, and other laboratory variables
ICU or HCU admission
Use of invasive mechanical ventilation, high-flow nasal cannula, or noninvasive ventilation
Use of vasopressors or inotropes
Use of renal replacement therapy
ICU/HCU length of stay
Hospital length of stay
In-hospital mortality
Postoperative 30-day mortality
Reoperation and other postoperative complications
Associations of salivary metabolites with sepsis according to infection source and with individual organ dysfunction

Study type

Observational

Basic design

Randomization

Randomization unit

Blinding

Control

Stratification

Dynamic allocation

Institution consideration

Blocking

Concealment

No. of arms

Purpose of intervention

Type of intervention

Interventions/Control_1

Interventions/Control_2

Interventions/Control_3

Interventions/Control_4

Interventions/Control_5

Interventions/Control_6

Interventions/Control_7

Interventions/Control_8

Interventions/Control_9

Interventions/Control_10

Age-lower limit

18

years-old

<=

Age-upper limit

Not applicable

Gender

Male and Female

Key inclusion criteria

Participants must meet all of the following criteria:

Preoperative salivary metabolomic analysis was performed at Yamagata University between April 11, 2016 and May 22, 2025, and the resulting data are available in the existing database
Salivary metabolomic data can be linked to clinical data from Yamagata University Hospital
The participant underwent surgery at Yamagata University Hospital after saliva collection
The participant was 18 years of age or older at the time of surgery
Clinical information required to evaluate infection and organ dysfunction within 30 days after surgery or during the index hospitalization is available

Key exclusion criteria

Participants meeting any of the following criteria will be excluded:

The planned surgery was not performed after saliva collection
Information required to determine the primary outcome, including infection-related data or SOFA score components, is substantially incomplete
Salivary metabolomic data cannot be appropriately linked to clinical data
The participant has opted out of the use of their data for this study
The principal investigator considers the participant unsuitable for inclusion for another reason

Target sample size

4000

Name of lead principal investigator

1st name	Ryuto
Middle name
Last name	Yokoyama

Organization

Yamagata University Faculty of Medicine

Division name

Department of Emergency Medicine

Zip code

990-9585

Address

2-2-2 Iida Nishi, Yamagata City, Yamagata Prefecture

TEL

0236331122

Email

ryusi0311@gmail.com

Name of contact person

1st name	RYUTO
Middle name
Last name	YOKOYAMA

Organization

Yamagata University Faculty of Medicine

Division name

Department of Emergency Medicine

Zip code

9909585

Address

2-2-2 Iida Nishi, Yamagata City, Yamagata Prefecture

TEL

0236285422

Homepage URL

Email

ryusi0311@gmail.com

Institute

Yamagata University

Institute

Department

Personal name

RYUTO YOKOYAMA

Organization

Yamagata University

Organization

Division

Category of Funding Organization

Other

Nationality of Funding Organization

Co-sponsor

Name of secondary funder(s)

Organization

Ethics Review Committee, Faculty of Medicine, Yamagata University

Address

2-2-2 Iida Nishi, Yamagata City, Yamagata Prefecture

Tel

0236331122

Email

ryusi0311@gmail.com

Secondary IDs

NO

Study ID_1

Org. issuing International ID_1

Study ID_2

Org. issuing International ID_2

IND to MHLW

Institutions

Date of disclosure of the study information

2026

Year

08

Month

13

Day

URL releasing protocol

Publication of results

Unpublished

URL related to results and publications

Number of participants that the trial has enrolled

Results

Results date posted

Results Delayed

Results Delay Reason

Date of the first journal publication of results

Baseline Characteristics

Participant flow

Adverse events

Outcome measures

Plan to share IPD

IPD sharing Plan description

Recruitment status

Preinitiation

Date of protocol fixation

2026

Year

08

Month

10

Day

Date of IRB

2026

Year

08

Month

10

Day

Anticipated trial start date

2026

Year

08

Month

14

Day

Last follow-up date

2030

Year

03

Month

31

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

Other related information

This single-center retrospective cohort study will include adults who underwent salivary metabolomic analysis between April 11, 2016 and May 22, 2025, followed by surgery at Yamagata University Hospital. All eligible patients with linkable metabolomic and clinical data will be included.

Existing salivary data will be linked to medical records, data warehouse, and DPC data using study identifiers. Variables will include patient characteristics, comorbidities, ASA Physical Status, laboratory data, surgical factors, cultures, antimicrobial treatment, SOFA components, organ support, ICU/HCU admission, length of stay, and mortality.

Suspected infection will be identified from infection diagnoses, therapeutic antimicrobial use, and culture sampling. Perioperative prophylaxis will be excluded. Postoperative sepsis will be defined as suspected infection within 30 days after surgery with an acute SOFA increase of at least 2 points attributable to infection. Final adjudication will use cultures, imaging, treatment, medical records, and clinical course.

Associations between preoperative salivary metabolites and postoperative sepsis will be assessed using multivariable models adjusted for patient and surgical factors. Analyses will account for the number of sepsis events and missing data. No new sampling, treatment, or research-specific intervention will be performed. Participants may opt out.

Registered date

2026

Year

08

Month

13

Day

Last modified on

2026

Year

08

Month

13

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000071619