Related Experiment Video

Updated: Jun 28, 2026

Symptom Assessment of Patients with Allergic Rhinitis Using an Allergen Exposure Chamber
08:47

Symptom Assessment of Patients with Allergic Rhinitis Using an Allergen Exposure Chamber

Published on: March 3, 2023

Decline in peak expiratory flow according to hourly short-term concentration of particulate matter in asthmatic

Hiroshi Odajima1, Shin Yamazaki, Hiroshi Nitta

  • 1Fukuoka National Hospital, Fukuoka, Japan.

Inhalation Toxicology
|October 28, 2008
PubMed

Insights

High levels of suspended particulate matter (SPM) significantly reduced morning peak expiratory flow (PEF) in asthmatic children during warmer months. These findings highlight the impact of air pollution on respiratory health in vulnerable populations.

Area of Science:

  • Environmental Health
  • Pediatric Pulmonology
  • Air Pollution Research

Background:

  • Asthma affects millions of children globally, with environmental factors like air pollution playing a significant role in exacerbating symptoms.
  • Particulate matter (PM) is a major air pollutant linked to adverse respiratory outcomes.

Purpose of the Study:

  • To investigate the association between short-term increases in suspended particulate matter (SPM) concentrations and lung function, specifically peak expiratory flow (PEF), in children with asthma.
  • To explore potential seasonal variations in the effects of SPM on PEF.

Main Methods:

  • Daily PEF measurements (morning and evening) were collected from 70 asthmatic children aged 4-11 in Fukuoka, Japan, over one year (April 2002-March 2003).
  • Generalized estimating equations were used to analyze the relationship between 3-hour mean SPM concentrations and PEF, accounting for seasonal effects (warmer vs. colder months).
  • Statistical models were adjusted for other air pollutants to ensure the robustness of the findings.

Main Results:

  • In warmer months, a 10 microg/m(3) increase in SPM concentration was associated with significant declines in morning PEF.
  • Specific SPM exposure periods (e.g., 2 a.m. to 5 a.m. same day, previous night) showed robust negative associations with morning PEF, even after adjusting for other pollutants.
  • Associations between SPM and evening PEF were weak and not statistically significant in warmer months.
  • No robust associations were found between SPM and PEF in colder months.

Conclusions:

  • Elevated 3-hour mean SPM concentrations are linked to reduced morning PEF in asthmatic children, particularly during warmer periods.
  • These findings underscore the importance of monitoring air quality and its impact on pediatric respiratory health, especially in susceptible populations.
  • The seasonal difference suggests that warmer months may pose a higher risk for asthmatic children concerning SPM exposure.

More Related Videos

Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults06:11

Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults

Published on: February 9, 2022

Related Concept Videos

Asthma III: Clinical Manifestations01:13

Asthma III: Clinical Manifestations

Asthma presents with a characteristic pattern of episodic respiratory symptoms that reflect underlying airway inflammation, bronchoconstriction, and mucus hypersecretion. Although severity varies among individuals, certain clinical manifestations are considered hallmarks of the disorder and often guide diagnosis and assessment.Respiratory SymptomsA persistent cough is one of the most common early features of asthma. It is frequently dry and tends to worsen at night or in the early morning,...
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features01:24

Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features

Chronic bronchitis is a key phenotype of chronic obstructive pulmonary disease (COPD), characterized by airway-centered inflammation and mucus overproduction. It develops from long-term exposure to harmful particles or gases, most commonly cigarette smoke, which triggers a persistent inflammatory response.Cellular and Structural ChangesInflammation initially affects the large bronchi and later the smaller airways, with infiltration by immune cells, including neutrophils, macrophages, and...
Asthma-III: Symptoms and Complications01:24

Asthma-III: Symptoms and Complications

Asthma, a common chronic respiratory condition, is classified considering the frequency and severity of symptoms alongside lung function impairment. Understanding this classification is essential for appropriate treatment and management. Here's a detailed look at the classification of asthma and its clinical features and complications:
Classification of Asthma
Inhaled Medications01:23

Inhaled Medications

Inhaled medications are crucial for managing chronic obstructive pulmonary disease (COPD) and asthma. They are essential for effective treatment and control, ensuring optimal respiratory health and well-being. Inhaled medication delivers drugs directly to the lungs, providing a rapid onset of action and reducing systemic side effects compared to oral or injectable medications. Three primary types of inhalation devices are used to administer these medications: nebulizers, metered-dose inhalers...
Asthma I: Introduction01:28

Asthma I: Introduction

Asthma is a chronic inflammatory disorder of the airways characterized by variable airflow obstruction and heightened bronchial responsiveness to a wide range of triggers. The underlying inflammation leads to airway swelling, mucus hypersecretion, and smooth muscle constriction, all of which narrow the airway lumen and impede airflow. Clinically, asthma presents with recurrent episodes of wheezing, shortness of breath, chest tightness, and coughing, symptoms that typically vary in intensity and...
Chronic Obstructive Pulmonary Disease II: Emphysema01:23

Chronic Obstructive Pulmonary Disease II: Emphysema

Emphysema, a major phenotype of chronic obstructive pulmonary disease (COPD), is characterized by irreversible destruction of alveolar walls and permanent enlargement of distal airspaces. Unlike chronic bronchitis, which primarily affects the airways, emphysema predominantly involves the lung parenchyma, where structural damage leads to airflow limitation.PathophysiologyIt most commonly results from prolonged exposure to cigarette smoke and other toxic gases, particularly cigarette smoke.