Asthma
Conditions
Keywords
severe asthma, poorly controlled asthma
Brief summary
Hypotheses: 1) Airway pH regulation is abnormal in severe asthma; 2) In severe asthma, there is formation of cytotoxic nitrogen oxides and loss of beneficial nitrogen oxides in the airways
Detailed description
Specific Aim 1:Test hypothesis that airway pH regulation is abnormal in severe asthma. 1a) Determine the effects of systemic corticosteroids on breath pH in children with severe and mild to moderate asthma. 1b) Examine whether breath condensate pH and other biomarkers of oxidant stress can predict clinical outcomes in children with severe and mild to moderate asthma. 1c) Identify whether increased Th1/Th2 cytokine ratio, and abnormalities in airway glutaminase, G-SNO-reductase, VATPase, and carbonic anhydrase are associated with airway pH disturbance in children with severe asthma. 1d) Test whether rhinovirus infections, which reduce airway pH, persist longer or are more frequent in children with severe asthma than in children with mild to moderate asthma. 1e) Examine the relationship between gastroesophageal reflux and proximal airway pH in children with severe asthma and mild to moderate asthma.
Interventions
None listed
Sponsors
The Cleveland Clinic
Emory University
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
6 Years to 21 Years
Healthy volunteers
No
Inclusion criteria
* At least 6 years old * Asthma diagnosis by physician * Current treatment with an inhaled corticosteroid medication
Exclusion criteria
* Bronchiectasis * Cystic Fibrosis * Chronic Obstructive Pulmonary Disease
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Exhaled Nitric Oxide at Baseline and Over the Observational Period | baseline and after 21 days | Exhaled nitric oxide concentrations as measured by collection of exhaled breath into a mylar bag |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Reduction in Breath pH | baseline and 21 days | Breath condensate pH was measured by the RTube (trademark) device. This device is a plastic tube with a one-way exhalation valve and a chilled aluminum sleeve. pH (the log of hydrogen ion concentration) was measured using an Orion pH meter and probe calibrated in 4.0, 7.0, and 10.0 pH solutions. |
Countries
United States
Participant flow
Recruitment details
Children were recruited from January 2003 to June 2011 from the Emory Children's Center asthma clinic.
Pre-assignment details
Children with physician diagnosed asthma were enrolled and underwent comprehensive phenotypic characterization consisting of pulmonary function measures, biomarker assessment, and allergy assessment.
Participants by arm
| Arm | Count |
|---|---|
| Children With Asthma The cohort consists of children with physician-diagnosed asthma across a wide range of severity (mild, moderate, severe) | 225 |
| Total | 225 |
Baseline characteristics
| Characteristic | Children With Asthma |
|---|---|
| Age, Categorical <=18 years | 225 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 0 Participants |
| Age, Continuous | 11.8 years STANDARD_DEVIATION 3.6 |
| Region of Enrollment United States | 225 participants |
| Sex: Female, Male Female | 102 Participants |
| Sex: Female, Male Male | 123 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 106 | 0 / 119 |
| serious Total, serious adverse events | 0 / 106 | 0 / 119 |
Outcome results
Primary
Exhaled Nitric Oxide at Baseline and Over the Observational Period
Exhaled nitric oxide concentrations as measured by collection of exhaled breath into a mylar bag
Time frame: baseline and after 21 days
Population: 225 children were enrolled into the study and completed baseline assessments. Only 40 children were followed longitudinally. The results from only those 40 children are shown here.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Children With Severe Asthma | Exhaled Nitric Oxide at Baseline and Over the Observational Period | Exhaled nitric oxide value at 21 days | 15.1 parts per billion | Standard Deviation 5.4 |
| Children With Severe Asthma | Exhaled Nitric Oxide at Baseline and Over the Observational Period | Exhaled nitric oxide baseline value | 13.7 parts per billion | Standard Deviation 7.4 |
| Children With Non-severe Asthma | Exhaled Nitric Oxide at Baseline and Over the Observational Period | Exhaled nitric oxide baseline value | 8.6 parts per billion | Standard Deviation 6.2 |
| Children With Non-severe Asthma | Exhaled Nitric Oxide at Baseline and Over the Observational Period | Exhaled nitric oxide value at 21 days | 9.9 parts per billion | Standard Deviation 5.8 |
Secondary
Reduction in Breath pH
Breath condensate pH was measured by the RTube (trademark) device. This device is a plastic tube with a one-way exhalation valve and a chilled aluminum sleeve. pH (the log of hydrogen ion concentration) was measured using an Orion pH meter and probe calibrated in 4.0, 7.0, and 10.0 pH solutions.
Time frame: baseline and 21 days
Population: 225 children with asthma were enrolled in the study and completed baseline assessments. Only 40 children were followed longitudinally. The data from those 40 children are shown here.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Children With Severe Asthma | Reduction in Breath pH | Breath pH at 21 days | 7.08 log of hydrogen ion concentration (pH) | Standard Deviation 0.52 |
| Children With Severe Asthma | Reduction in Breath pH | Breath pH at baseline | 7.68 log of hydrogen ion concentration (pH) | Standard Deviation 0.69 |
| Children With Non-severe Asthma | Reduction in Breath pH | Breath pH at 21 days | 7.58 log of hydrogen ion concentration (pH) | Standard Deviation 0.32 |
| Children With Non-severe Asthma | Reduction in Breath pH | Breath pH at baseline | 7.63 log of hydrogen ion concentration (pH) | Standard Deviation 0.88 |