The Impact of Dosimeter on Measurement of Airway Responsiveness to Methacholine

• Status: Completed
• Trial end date: 2005-12-01
• Target enrollment: 0
• Participant gender: All

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.

• Phase: N/A
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: University of Florida
• Collaborator: GlaxoSmithKline
• Treatments: Methacholine Chloride

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.