A 13-year study of Japanese cedar pollinosis in Japanese schoolchildren
Related Experiment Video
Updated: Jul 5, 2026
A Component-resolved Diagnostic Approach for a Study on Grass Pollen Allergens in Chinese Southerners with Allergic Rhinitis and/or Asthma
Published on: June 4, 2017
Kotaro Ozasa1, Takemitsu Hama, Kenji Dejima
1Department of Epidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, Japan. kozasa@koto.kpu-m.ac.jp
Insights
Japanese cedar pollen (JCP) sensitization is linked to birth year and pollen exposure. While recent birth cohorts are more easily sensitized, they do not develop more symptoms, unlike house dust mite sensitization in boys.
Area of Science:
- Allergy and Immunology
- Environmental Health
- Pediatrics
Background:
- Japanese cedar pollinosis (JCPS) prevalence is rising in young children.
- Investigating factors influencing Japanese cedar pollen (JCP) sensitization and JCPS development is crucial.
Purpose of the Study:
- To identify factors associated with JCP sensitization in school children.
- To understand the development of JCPS and its relationship with JCP sensitization.
Main Methods:
- Longitudinal study from 1994-2006 involving 275-510 children annually.
- Assessed serum JCP-IgE and house dust mite (HDM)-IgE levels.
- Conducted surveys on rhinoconjunctival symptoms.
Main Results:
- JCP sensitization correlated with age, pollen levels (current and post-birth), birth month, and recent birth cohort.
- HDM sensitization associated with gender (less in girls) and recent birth cohort.
- Symptoms negatively correlated with recent birth cohort after adjusting for JCP-IgE.
Conclusions:
- Recent birth cohorts and early-life pollen exposure increase JCP sensitization risk.
- Recent birth cohorts are more prone to sensitization but not necessarily symptoms.
- HDM sensitization appears earlier and affects boys more, unlike JCP sensitization.
Background:
Japanese cedar pollen (JCP) sensitization and Japanese cedar pollinosis (JCPS) appear to be increasingly prevalent in younger children. The present study investigated factors affecting JCP sensitization and JCPS development in school children.
Methods:
In May or June each year from 1994 to 2006, 275-510 children were assessed for serum JCP-IgE and house dust mite (HDM)-IgE levels, and surveyed regarding rhinoconjunctival symptoms.
Results:
Strong JCP sensitization (IgE > or = 17.5 U(A)/ml) was associated with age (odds ratio (OR) = 2.65), the amount of dispersed pollen in the observed year (OR = 2.03) and in the year following birth (OR = 1.51), the month of birth (OR = 2.18), and the recent birth cohort (OR = 1.96). Symptoms were negatively correlated with the recent birth cohort (OR = 0.69) after adjusting for JCP-IgE levels. Strong HDM sensitization was associated with gender (OR = 0.65 for girls) and the recent birth cohort (OR = 1.76).
Conclusions:
JCP sensitization appeared to be associated with the recent birth cohort and to increases in dispersed pollen just after birth and in the observed season. Although the recent birth cohort was more easily sensitized, they were not more likely to develop symptoms. In contrast to JCP sensitization, strong HDM sensitization appeared to develop prior to commencement of primary school and was more likely to affect boys.
Related Concept Videos
01:24Asthma-III: Symptoms and Complications
Classification of Asthma
01:13Asthma III: Clinical Manifestations
01:20Sputum Studies II: Culture and Sensitivity
Sputum culture and sensitivity is a medical procedure used to diagnose bacterial infections in the respiratory tract and select the most appropriate antibiotics for treatment. This process involves analyzing sputum samples of thick and opaque secretions produced in the lungs and airways. These samples are collected from patients and then sent to the laboratory for analysis.
The test can identify various pathogens responsible for respiratory infections, including Streptococcus,...