Different End Points for Bronchial Hyperactivity (BHR) Tests.

Different End Points for Bronchial Hyperactivity (BHR) Tests, What Comes First?

Bronchial challenge tests (BCT) are being used to diagnose bronchial hyperactivity (BHR) and quantify its severity.In older children and adults, BCT is done using spirometry to measure the value of 20% fall in FEV1 as an indicator for positive reactivity.

However, in young children and infants that cannot perform spirometry, other measurements are used as indicators for BHR. Traditionally, in these populations, appearance of wheezing on auscultation is used as the indicator for BHR. More recently, other measures like 50% increase in respiratory rate or 5% decreases in oxygen saturation are mentioned as possible options to determine positive BHR. Nevertheless, as these measurements probably measure different parameters they could vary in time of appearance.

The investigators also noted that in older children who perform spirometry, the order of appearance of these different physiologic measures is not constant.

Decrease in O2 saturation, appearance of wheezing and increase in respiratory rate (RR) do not all appear at the same time and not in the same order of events.

Some children are noted to have a decrease in FEV1 without wheezing - those children can be difficult to diagnose as asthmatics in the primary care setting where asthma is being diagnosed on clinical grounds alone: wheezing and response to bronchodilators. Children who do not wheeze are difficult to diagnose and therefore, are not getting the appropriate treatment.

Nevertheless, the data in current literature is very scant or not existing regarding these issues. Thus the investigators designed a study to prospectively try to answer the questions: do clinically significant differences exist in the concentration of the metacholine and / or adenosine at the time time of appearances of these parameters, what comes first, and if so, how does it affect the diagnosis and the severity assessment of HRA in different age groups?

Study Overview

• Status: Completed
• Conditions: Bronchial Hyperreactivity

Detailed Description

Bronchial challenge tests (BCT) are being used to diagnose bronchial hyperactivity (BHR) and quantify its severity.

In older children and adults, BCT is done using spirometry to measure the value of 20% fall in FEV1 as an indicator for positive reactivity. However, in young children and infants that cannot perform spirometry, other measurements are used as indicators for BHR. Traditionally, in these populations, appearance of wheezing on auscultation is used as the indicator for BHR. More recently, other measures like 50% increase in respiratory rate or 5% decreases in oxygen saturation are mentioned as possible options to determine positive BHR. Nevertheless, as these measurements probably measure different parameters they could vary in time of appearance.

The investigators also noted that in older children who perform spirometry, the order of appearance of these different physiologic measures is not constant.

Decrease in O2 saturation, appearance of wheezing and increase in respiratory rate (RR) do not all appear at the same time and not in the same order of events.

Some children are noted to have a decrease in FEV1 without wheezing - those children can be difficult to diagnose as asthmatics in the primary care setting where asthma is being diagnosed on clinical grounds alone: wheezing and response to bronchodilators. Children who do not wheeze are difficult to diagnose and therefore, are not getting the appropriate treatment.

Nevertheless, the data in current literature is very scant or not existing regarding these issues. Thus the investigators designed a study to prospectively try to answer the questions: do clinically significant differences exist in the time of appearances of these parameters and if so, how does it affect the diagnosis and the severity assessment of HRA in different age groups? in this study we measure the metacholine and / or adenosine concentration at the time when the following parameters appear (what comes first): 20% fall in FEV1, 5% fall in oxygen saturation, 50% rise in respiratory rate, wheezing heard by the investigators using stethoscope.

• Study Type: Observational
• Enrollment (Actual): 501

Contacts and Locations

Study Locations

• Israel
  • Holon, Israel
    • The Edith Wlofson Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 1 year to 16 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Patients referred for HRA trigger testing.

Description

Inclusion Criteria:

• Patients referred for HRA trigger testing

Exclusion Criteria:

• None

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Which of the outcome ends points measures comes first in the diagnosis of bronchial hypersensitiveness.	Increasing concentrations of Metacholine or adenosine inhalations are given until there are 20% fall in FEV1 and / or 5% decrease in saturation and / or 50% increase in RR. The concentrations on which these outcomes occur are measured.	On which metacholine and / or adenosine increasing concentrations, there are 20% fall in FEV1 and / or 5% decrease in saturation and / or 50% increase in RR. Which comes first. Time frame: each BHR tests last up to two hours.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Age influence on which comes first outcomes.	Age in years and months will be recorded. Age influence on the distribution of the main outcome - which comes first - will be calculated.	The time frame of the study: four years.

Collaborators and Investigators

• Sponsor: Wolfson Medical Center
• Investigators: Principal Investigator: Avigdor Madnelberg, MD, The Sackler School of Medicine, Tel-Aviv University, Israel; Principal Investigator: Avigdor Mandelberg, MD, Tha Sackler School of Medicine, Tel-Aviv University, Israel

Publications and helpful links

General Publications

• Ater D, Amirav I, Attias M, Nakash E, Newhouse MT, Mandelberg A. Evaluation of clinically and physiologically atypical asthma: If it doesn't wheeze it may still be asthma. J Asthma. 2019 Jan;56(1):21-26. doi: 10.1080/02770903.2018.1424194. Epub 2018 Feb 2.

Study record dates

Study Major Dates

• Study Start: September 1, 2011
• Primary Completion (Actual): December 1, 2014
• Study Completion (Actual): December 1, 2014

Study Registration Dates

• First Submitted: July 26, 2011
• First Submitted That Met QC Criteria: July 28, 2012
• First Posted (Estimate): August 1, 2012

Study Record Updates

• Last Update Posted (Estimate): December 11, 2014
• Last Update Submitted That Met QC Criteria: December 10, 2014
• Last Verified: December 1, 2014

More Information

Terms related to this study

• Keywords: BRONCHIAL CHALLANGE TEST, ASTHMA, METACHLINE, ADENOSINE
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Bronchial Diseases; Bronchial Hyperreactivity
• Other Study ID Numbers: AD-S