Overview

Mechanisms for Dyspnea on Exertion in Children With Obesity and Asthma: Distinct Physiological Phenotypes

Status:
Not yet recruiting
Trial end date:
2028-03-31
Target enrollment:
0
Participant gender:
All
Summary
The overall objective of this study is to better understand the respiratory mechanisms provoking DOE in obese asthmatic children to inform directive management for clinicians.
Phase:
Phase 4
Accepts Healthy Volunteers?
No
Details
Lead Sponsor:
Ohio State University
University of Nevada, Las Vegas
Collaborator:
Nationwide Children's Hospital
Treatments:
Albuterol
Bromides
Ipratropium
Criteria
General inclusion criteria:

- Age range: 9-17 years of age

- Participants with physician diagnosed asthma and on regular asthma controller therapy
for at least 8 weeks prior to enrollment will be recruited for this study.

o Objectively Confirmed Asthma Diagnosis: Asthma diagnosis will be confirmed
objectively using spirometry (FEV1 < 80% predicted or FEV1/FVC < lower limit of
normal), bronchodilator reversibility testing (post-bronchodilator improvement of ≥
12% and 200mL in FEV1 or FVC; or a decrease in lung hyperinflation of at least 150 mL;
ATS guidelines on lung function test interpretation), or a methacholine challenge
test. Patients in whom asthma cannot be confirmed objectively will be excluded from
the study.

- Ability to communicate in English

Body mass index criteria (BMI): We will study two discrete groups of asthmatic children
based on their BMI percentile:

- Nonobese: BMI 5th-84th percentile based on norms from the Centers for Disease Control
(CDC)

- Obese: BMI ≥95th percentile and less than 170% of the 95th BMI percentile based on
norms from the CDC

Exclusion criteria:

Criteria for pulmonary function: We will exclude asthmatic children with:

- Severe asthma: Forced expiratory volume in 1s (FEV1) < 50% predicted

- Restrictive pulmonary disease: Forced vital capacity (FVC) and total lung capacity
(TLC) < 80% predicted

- Diffusion limitation: Diffusing capacity relative to alveolar volume (DLCO/VA) < 80%
predicted

Daily activity levels: Children participating in regular vigorous conditioning exercise
such as running, jogging, aerobics, cycling, or swimming for ≥60min/session and ≥five times
per week will be excluded to ensure similarity in physical activity levels between subjects
and to avoid enrolling a potential high-fit, extremely active child. Children who
participate in daily, unorganized physical activity (i.e., majority of children), will not
be excluded. Children who are sedentary or only participate in school physical education
classes will not be excluded.

The following exclusion criteria will be used in this study:

- History of oral steroid medications for 4 weeks prior to enrollment

- History of being admitted to an intensive care unit or being intubated because of
their asthma in the past five years

- History of allergy or hypersensitivity to albuterol or ipratropium or history of
narrow-angle glaucoma that could get worse with ipratropium

- History of vocal cord dysfunction

- History of obesity hypoventilation syndrome

- History of untreated sleep apnea

- History of heart disease, metabolic disease, or renal disease that, in the opinion of
the PI (or co-I's), would increase the risks of exercise testing or alter the
physiological responses to exercise

- History of significant mental illness that in the opinion of the PI (or co-I's) would
interfere with study participation or increase risks to the participant

- History of musculoskeletal abnormality that would preclude cycling exercise

- Pregnant or become pregnant during their participation in the study

- History of other significant illnesses that, in the opinion of the PI (or co-I's),
either increase risks of participation or alter the physiological responses to
exercise

- Inability to successfully complete pulmonary function or exercise testing measurements
or difficulty with following instructions during testing

- Inability to tolerate testing procedures or complications related to testing

- If a participant develops hypoxemia or meets indications for terminating exercise, the
exercise test will be terminated, and the participant will be referred for further
evaluation In general, all participants will be encouraged to follow up with their
asthma care provider or pediatrician for any health concerns that are discovered
during their participation.