UMIN-ICDS Clinical Trial

Public title

An Exploratory Study on Longitudinal Changes in Urinary IgA Concentrations Among Junior High School Students During the High School Entrance Examination Period

Acronym

An Exploratory Study on Longitudinal Changes in Urinary IgA Concentrations Among Junior High School Students During the High School Entrance Examination Period

Scientific Title

An Exploratory Study on Longitudinal Changes in Urinary IgA Concentrations Among Junior High School Students During the High School Entrance Examination Period

Scientific Title:Acronym

An Exploratory Study on Longitudinal Changes in Urinary IgA Concentrations Among Junior High School Students During the High School Entrance Examination Period

Region

Japan

Condition

immunity

Classification by specialty

Child

Classification by malignancy

Others

Genomic information

NO

Narrative objectives1

uring the entrance examination preparation period, major health management challenges for students include irregular lifestyle habits-such as chronic sleep deprivation, physical inactivity, and nutritional imbalances-as well as psychological burdens, including severe stress and anxiety. These factors often lead to physical and mental distress, accompanied by an increased risk of infectious diseases. Consequently, they can impair students' daily school life and undermine their physical and cognitive performance on examination days.
Although various approaches have been explored to address these issues, few studies have addressed them from an immunological perspective. Immune status is likely linked both to upstream factors, such as lifestyle habits and psychological stress, and to downstream outcomes, such as infection risk. Therefore, quantifying individual immune status could serve a dual purpose: enabling students to evaluate the efficacy of lifestyle modifications and stress-reduction strategies, while fostering heightened awareness regarding infection prevention. This approach has the potential to contribute meaningfully to resolving the aforementioned challenges. As a critical first step, this study aims to assess longitudinal changes and fluctuations in immune status among students throughout the examination preparation period.

Basic objectives2

Bio-equivalence

Basic objectives -Others

Trial characteristics_1

Trial characteristics_2

Developmental phase

Primary outcomes

Longitudinal changes in urinary IgA concentrations (creatinine-corrected value: IgA/creatinine ratio)
this study measures urinary renalase, cytokines (IL-6 and IL-8), titin N-terminal fragment, myoglobin, cell-free DNA (cfDNA), cell-free RNA (cfRNA)-both restricted to fragment size measurement and quantification without sequence identification-and the indole test as a gut microbiota marker, to examine their associations with daily physical activity levels.
(Time points: Assessed at four time points across the study period [late October-early November, early-mid December, early-mid January, and mid-late February])

Key secondary outcomes

Dietary habits (breakfast habits, balanced meals combining staple food, main dish, and side dishes, protein intake, frequency of consuming sweets and sugary drinks), sleep (duration, quality, feeling of recovery from sleep), physical activity (habit of exercising for >=30 minutes, exercise on holidays, sedentary time), psychological well-being (WHO-5 Well-Being Index), stress (Perceived Stress Scale: PSS-4), health status (presence or absence of cold-like symptoms, school absenteeism), immune-care behaviors (presence or absence, selection of specific behaviors), history of events related to entrance examinations (mock exams, school exams, interviews, etc.)
(Time points: Assessed at four time points across the study period [late October-early November, early-mid December, early-mid January, and mid-late February])

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

13

years-old

<

Age-upper limit

15

years-old

>=

Gender

Male and Female

Key inclusion criteria

This study will be conducted with second- and third-year students from our university-affiliated junior high schools. The eligibility criteria for participation are as follows:
Second- or third-year male and female students enrolled at the Yokohama Junior High School or Kamakura Junior High School affiliated with Yokohama National University.
Students whose parents or legal guardians have received a comprehensive explanation regarding the purpose and procedures of this study and have provided written informed consent for their child's participation.
Students who received an explanation using an assent document and voluntarily agreed to participate.

Key exclusion criteria

This study will be conducted with second- and third-year students from our university-affiliated junior high schools. The exclusion criteria for participation are as follows:
Students who are unable to collect their own urine samples using the designated procedure.
Students who have an autoimmune disease and are currently undergoing medical treatment or pharmacotherapy.
Students who have kidney disease or renal dysfunction and are currently undergoing medical treatment or pharmacotherapy.
Any other students deemed unsuitable for participation by the principal investigator.

Target sample size

200

Name of lead principal investigator

1st name	Katsuyuki
Middle name
Last name	Tokinoya

Organization

Yokohama National University

Division name

College of Education

Zip code

240-8501

Address

79-2 Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa

TEL

0453393277

Email

tokinoya-katsuyuki-ys@ynu.ac.jp

Name of contact person

1st name	Katsuyuki
Middle name
Last name	Tokinoya

Organization

Yokohama National University

Division name

College of Education

Zip code

240-8501

Address

79-2 Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa

TEL

0453393277

Homepage URL

Email

tokinoya-katsuyuki-ys@ynu.ac.jp

Institute

Yokohama National University

Institute

Department

Personal name

Organization

Kirin Holdings Company, Limited.

Organization

Division

Category of Funding Organization

Profit organization

Nationality of Funding Organization

Japan

Co-sponsor

Kirin Health Sciences Institute, Kanagawa Technology Innovations Inc.

Name of secondary funder(s)

Organization

Yokohama National University

Address

Yokohama National University

Tel

0453393075

Email

kenkyu.somu@ynu.ac.jp

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

10

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

10

Month

13

Day

Date of IRB

2026

Year

10

Month

07

Day

Anticipated trial start date

2026

Year

10

Month

13

Day

Last follow-up date

2029

Year

03

Month

31

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

Other related information

This study aims to continuously monitor the immune status of junior high school students preparing for entrance examinations to clarify its chronological changes, as well as to investigate its associations with lifestyle habits, subjective health status, and the onset of infectious diseases. Furthermore, this study will exploratorily evaluate whether providing feedback on the measurement results to the students leads to improvements in lifestyle habits and the implementation of infection prevention behaviors.

Registered date

2026

Year

10

Month

08

Day

Last modified on

2026

Year

10

Month

08

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000072367