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The Impact of Dosimeter on Measurement of Airway Responsiveness to Methacholine

Primary Purpose

Asthma

Status
Completed
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
methacholine
KoKo Digidoser
Rosethal Dosimeter
Sponsored by
University of Florida
About
Eligibility
Locations
Outcomes
Full info

About this trial

This is an interventional diagnostic trial for Asthma focused on measuring methacholine PC20, dosimeter, asthma

Eligibility Criteria

18 Years - 60 Years (Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria: Non-smoking male or female >18 years of age, with a previous diagnosis of asthma. Women of child bearing age must not be pregnant or nursing and be using an acceptable method of contraception. Screening FEV1 > 70% of predicted for height, age, sex, and race when bronchodilators are withheld for appropriate intervals. At least a 20% decrease in FEV1 after inhaling ≤ 8 mg/ml of methacholine (i.e., a PC20 FEV1 ≤8 mg/ml) using the KoKo Digidoser system. Ability to perform ATS-acceptable and reproducible spirometry. Exclusion Criteria: Cigarette smoking in past year or > 10 pack year smoking history. Respiratory tract infection within the last four weeks. History of severe asthma attack requiring hospitalization in the previous 12 months. Short course of oral corticosteroids in the past 3 weeks. Inability to withhold caffeinated beverages for 12 hours or medications for appropriate intervals prior to each methacholine challenge. If female, a positive urine β-HCG test.

Sites / Locations

  • University of Florida Asthma Research Lab

Outcomes

Primary Outcome Measures

Geometric mean PC20 methacholine for each dosimeter method.

Secondary Outcome Measures

Full Information

First Posted
September 1, 2005
Last Updated
March 1, 2012
Sponsor
University of Florida
Collaborators
GlaxoSmithKline
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1. Study Identification

Unique Protocol Identification Number
NCT00145990
Brief Title
The Impact of Dosimeter on Measurement of Airway Responsiveness to Methacholine
Study Type
Interventional

2. Study Status

Record Verification Date
March 2012
Overall Recruitment Status
Completed
Study Start Date
September 2005 (undefined)
Primary Completion Date
December 2005 (Actual)
Study Completion Date
December 2005 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
University of Florida
Collaborators
GlaxoSmithKline

4. Oversight

5. Study Description

Brief Summary
To determine whether there is a difference in two different breathing tests used to detect asthma. Hypothesis: The Digidoser delivers less methacholine to the airways and will result in a higher PC20 than the value determined by the Rosenthal Dosimeter.
Detailed Description
Bronchoprovocation with methacholine is used to confirm the diagnosis of asthma. The procedure involves inhaling methacholine through a nebulizer attached to a dosimeter that delivers a precise volume of methacholine. The endpoint of the test is the provocational concentration that produces a 20% decrease in FEV1 (PC20). To standardize the procedure, the American Thoracic Society (ATS) recommends that the nebulizer output be calibrated to deliver an output of 0.9 ± 0.09 mL/min. The Rosenthal Dosimeter and the KoKo Digidoser are two commonly used dosimeters. In an attempt to follow the ATS guideline we discovered that the nebulizer output was lower with the KoKo Digidoser and could not be calibrated. However, it is unclear whether the apparent lower output is a result of the Digidoser delivering less solution or that the ATS method of determining output is not applicable to this dosimeter. To answer this question, we propose to determine the methacholine PC20 in subjects with asthma using the two dosimeters. It is our hypothesis that the Digidoser delivers less methacholine and thus will produce a higher PC20 than the Rosenthal Dosimeter. Twelve nonsmoking subjects with mild asthma will be selected on the basis of > 18 years of age, a baseline FEV1 of > 60% predicted and a screening PC20 of < 8mg/ml. Subjects will be randomized to perform a methacholine challenge with the Digidoser and the Rosenthal Dosimeter on two different days in an unblinded, crossover manner. The geometric mean PC20 with each dosimeter will be compared with a paired t test. The results of this study will indicate whether the Digidoser has the potential of causing false negative test results or whether the ATS method of determining output should not be used with this dosimeter.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Asthma
Keywords
methacholine PC20, dosimeter, asthma

7. Study Design

Primary Purpose
Diagnostic
Study Phase
Not Applicable
Interventional Study Model
Crossover Assignment
Masking
None (Open Label)
Allocation
Randomized
Enrollment
12 (false)

8. Arms, Groups, and Interventions

Intervention Type
Drug
Intervention Name(s)
methacholine
Intervention Type
Device
Intervention Name(s)
KoKo Digidoser
Intervention Type
Device
Intervention Name(s)
Rosethal Dosimeter
Primary Outcome Measure Information:
Title
Geometric mean PC20 methacholine for each dosimeter method.

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
60 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria: Non-smoking male or female >18 years of age, with a previous diagnosis of asthma. Women of child bearing age must not be pregnant or nursing and be using an acceptable method of contraception. Screening FEV1 > 70% of predicted for height, age, sex, and race when bronchodilators are withheld for appropriate intervals. At least a 20% decrease in FEV1 after inhaling ≤ 8 mg/ml of methacholine (i.e., a PC20 FEV1 ≤8 mg/ml) using the KoKo Digidoser system. Ability to perform ATS-acceptable and reproducible spirometry. Exclusion Criteria: Cigarette smoking in past year or > 10 pack year smoking history. Respiratory tract infection within the last four weeks. History of severe asthma attack requiring hospitalization in the previous 12 months. Short course of oral corticosteroids in the past 3 weeks. Inability to withhold caffeinated beverages for 12 hours or medications for appropriate intervals prior to each methacholine challenge. If female, a positive urine β-HCG test.
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Yasmeen Khan, MD
Organizational Affiliation
University of Florida
Official's Role
Principal Investigator
Facility Information:
Facility Name
University of Florida Asthma Research Lab
City
Gainesville
State/Province
Florida
ZIP/Postal Code
32610
Country
United States

12. IPD Sharing Statement

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The Impact of Dosimeter on Measurement of Airway Responsiveness to Methacholine

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