The Dallas Asthma Brain and Cognition (ABC) Study

July 3, 2025 updated by: Sherwood Brown, MD, PhD, University of Texas Southwestern Medical Center
Asthma is a chronic inflammatory airway disease that leads to episodic symptom exacerbations, which exerts a substantial burden on quality of life and can influence other health domains if not adequately controlled. Asthma prevalence rates have increased in the past decade, affecting 8.4% (25.7 million people) of the United States population. The economic costs of asthma have been estimated annually with $56 billion in the US alone. Despite progress in pharmacological treatment, overall asthma control remains unsatisfactory and treatment non-adherence is extremely high. Asthma is particularly under diagnosed and understudied in aging adults. This problem will increase in coming decades given demographic trends and will disproportionally contribute to the societal and personal economic costs associated with asthma treatment and management. In the proposed 4-year project we will evaluate, in a two-session assessment recruiting a total of 126 asthma patients and 66 healthy controls aged 40-69 years, the extent to which asthma and aging are associated with changes in cognition and brain chemistry, structure, and function.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This study will implement a cross-sectional design, conducted across two sessions. The first session will capture cognitive performance, health history, and relevant social, behavioral, and emotional processes. The second session approximately one week later will capture neural structure, function, and chemistry. In the first session, participants will undergo screening for psychological disorders, neuropsychological testing and pulmonary function assessment at the Southern Methodist University (SMU) or UT Southwestern site. They will then participate in a second session at University of Texas Southwestern Medical Center (UTSW) Advanced Imaging Research Center (AIRC) with structural and functional magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), and brain metabolic activity with spectroscopy. Blood draws and additional pre- and post-neuroimaging spirometry will also be performed at the second session. Potential participants identified by brief phone screen will be invited for two assessment sessions 1 week apart. At the first session, they will be consented, interviewed about their asthma and/or general health status, and pulmonary function tests will be performed. They will then fill in questionnaires and will be screened for psychological disorders by standardized psychiatric interview. After that, they will complete the neuropsychological test battery. The second session will entail spirometry (to ascertain adequate lung function for imaging), the 1 ½ hour neuroimaging protocol, saliva samples, and blood sampling. Spirometry will be repeated at the end of the imaging session. We will also offer patients a brief optional session before the imaging session to get acquainted to the scanning environment in a mock scanner.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
130

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • United States
    • Texas
      • Dallas, Texas, United States, 75390
        • The University of Texas Southwestern Medical Center
      • Dallas, Texas, United States, 75206
        • Southern Methodist University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

40 years to 69 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

Subjects will be recruited from the larger Dallas/ Fort Worth community. We will recruit both healthy controls and subjects with asthma through local flyers, online advertisements, at community allergy and pulmonary clinics, and databases. Individuals who appear eligible will be invited to participate.

Description

Inclusion Criteria:

  • For asthma patients: diagnosis of asthma (verified by a medical documentation) for at least 2 years; for healthy volunteers: no significant medical or psychiatric history.
  • Ages 40 to 69 years old.
  • Proficient in English.
  • Education level of at least 10th grade level.

Exclusion Criteria:

  • Treatment with oral corticosteroids in the previous 6 weeks, because of the potent effects of this drug on airway reactivity.
  • Spirometry: Peak expiratory flow (PEF) below 60% of predicted.
  • Diagnosis of vocal cord dysfunction (identified by abnormalities in spirometric flow-volume curves), clinically significant chronic obstructive pulmonary disease, or emphysema.
  • Presence or history of medical or neurological disorder that may affect brain function and the physiological systems of interest (e.g. angina, myocardial infarction, congestive heart failure, transient ischemic attacks, cerebrovascular accidents, emphysema, or chronic obstructive pulmonary disease, history of seizures or head trauma, endocrine disorders or renal disease, chemotherapy or radiation presently or in the past 5 years, uncontrolled diabetes, blood pressure above 160/90 (self-reported or measured at session 1).
  • Corrected vision poorer than 20/30 on Snellen Eye Chart.
  • Presence or history of Schizophrenia, Psychosis, Dementia, Bipolar I, Bipolar II, PTSD or Acute Stress Disorder
  • Current or recent history (within 1 year) of Substance Related Disorders, current recreational drug use (defined as past 30 days) or consuming more than 20 alcoholic drinks per week.
  • Current treatment with anti-psychotics, sedatives, benzodiazepines with a half-life longer than 6 hours.
  • Previous electroconvulsive therapy.
  • Presence of history of orthopaedic circumstances and metallic inserts interfering with MR scanning (prior surgeries and/or implant pacemakers, pacemaker wires, artificial heart value, brain aneurysm surgery, middle ear implant, non-removable hearing aid or jewelry, braces or extensive dental work, cataract surgery or lens implant, implanted mechanical or electrical device, artificial limb or joint, foreign metallic objects in the body such as bullets, BB's, shrapnel, or metalwork fragments, pregnancy, claustrophobia, uncontrollable shaking, or inability to lie still for one hour.
  • Not proficient in English.
  • In the opinion of the principal investigator, participant is otherwise unsuitable for this study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Asthma patients
Asthma patients will undergo behavioral testing and imaging at a single timepoint.
Other: Functional and Structural Magnetic Resonance Imaging (research grade)
Brain structure and function will be compared in middle to late-age adults with asthma compared to healthy adults.
Other: Cognitive Function Testing (non-diagnostic)
Multiple domains of cognitive functioning will be investigated, including processing speed, executive functioning/working memory and episodic memory.
Other: Asthma and Psychological Questionnaires (non-diagnostic)
Participants will fill out asthma and psychological questionnaires (non-diagnostic)
Healthy Volunteers
Healthy volunteers will undergo behavioral testing and imaging at a single timepoint.
Other: Functional and Structural Magnetic Resonance Imaging (research grade)
Brain structure and function will be compared in middle to late-age adults with asthma compared to healthy adults.
Other: Cognitive Function Testing (non-diagnostic)
Multiple domains of cognitive functioning will be investigated, including processing speed, executive functioning/working memory and episodic memory.
Other: Asthma and Psychological Questionnaires (non-diagnostic)
Participants will fill out asthma and psychological questionnaires (non-diagnostic)

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Examine processing speed of middle- to late-age adults with asthma with the Wechsler Adult Intelligence Scale (WAIS) Symbol Search Test.
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
The Wechsler Adult Intelligence Scale (WAIS) Symbol Search test is a subtest of the WAIS, a scale widely used to measure intelligence. The examinee scans a search group of symbols and indicates whether one of the symbols matches a symbol in the target group. The time limit for this subtest is 120 seconds. The total raw score is the sum of the number of correct responses minus the number of incorrect responses. A higher score indicates better performance. The maximum total raw score is 60. If the total raw score is equal to or less than 0, then the total raw score is recorded as 0.
From date of baseline until the date of second session, approximately one week after baseline.
Examine executive functioning of middle- to late-age adults with asthma with the Trails A&B test.
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
The Trails A&B test is a neuropsychological assessment. The task requires a subject to connect a sequence of 25 circles on a sheet of paper as quickly as possible. The test has 2 parts, with the first part of the test requiring the subject to connect circles that are all numbers (1, 2, 3, etc.) in order. The second part of the test requires that the subject alternates between numbers and letters (1, A, 2, B, etc.). The time taken for each part, measured in seconds, is the raw score. The score is then converted to a scaled score and a T score, both based on sex (male, female), race, and age. A higher score indicates better performance.
From date of baseline until the date of second session, approximately one week after baseline.
Examine working memory of middle- to late-age adults with asthma with the National Institute of Health (NIH) Sorting Working Memory Test.
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
The National Institute of Health Sorting Working Memory Test is a computerized test that requires the subject to sequence sets of visually and auditorily presented stimuli (pictures of animals and food) in size order from smallest to biggest. There are two lists, with the 1-list version requiring sequencing among a single category (either animals or food), and the 2-list version (requiring sequencing of both food and animals within a series). The raw score is based on the sum of the correct across both lists, which comprise the List Sorting "Total Score". The raw score is converted into a t-score (mean = 50, standard deviation = 10). A higher score indicates better performance.
From date of baseline until the date of second session, approximately one week after baseline.
Examine episodic memory of middle- to late-age adults with asthma with the Rey Auditory Verbal Learning Test (RAVLT).
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
The examiner reads a list of 15 nouns aloud at the rate of one per second. The subject is asked to repeat all words they recall over 5 trials. An interference list (List B) is then read and subject is asked to recall. Immediately following the interference trial, the subject is asked to recall words from List A (Trial 6). After a 20 minute delay the subject is asked to recall as many words as possible from the first list (delayed recall). A list of 50 words is presented containing all words from List A and the subject is asked to indicate whether each word was on List A (recognition task). The total score (Trials 1-5) is calculated by summing the correct number of words for each trial. List B, Trial 6 and Delayed Recall are calculated by summing the correct number of words. Recognition task is scored by taking the number of correct words and subtracting the number of false positive words. Scores are converted into t-scores with higher score indicating better performance.
From date of baseline until the date of second session, approximately one week after baseline.
Examine reasoning of middle- to late-age adults with asthma with the National Adult Reading Test (NART).
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
The National Adult Reading Test is a commonly used test to measure intellectual ability in English-speaking patients. A list of 50 words, whose pronunciation cannot be determined from their spelling, are given to the subject and the subject is asked to read down the list. The examiner marks whether the subject pronounced the word correctly and the NART is scored by summing the number of words pronounced correctly.
From date of baseline until the date of second session, approximately one week after baseline.
Examine brain function of adult asthma patients from age 40-69 with functional magnetic resonance imaging (fMRI)
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
We will assess brain functioning by measuring default brain network connectivity using functional magnetic resonance imaging (fMRI)
From date of baseline until the date of second session, approximately one week after baseline.
Examine brain structure of adult asthma patients from age 40-69 with structural magnetic resonance imaging (sMRI)
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
We will assess brain structure, hippocampal gray matter volume, using structural magnetic resonance imaging (sMRI)
From date of baseline until the date of second session, approximately one week after baseline.
Examine brain chemistry of adult asthma patients from age 40-69 with proton magnetic resonance spectroscopy (1H-MRS)
Time Frame: From date of baseline until the date of second session, approximately one week after baseline.
We will assess brain chemistry, specifically differences in hippocampal metabolite levels, using proton magnetic resonance spectroscopy (1H-MRS)
From date of baseline until the date of second session, approximately one week after baseline.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Texas Southwestern Medical Center

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Southern Methodist University

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: E. Sherwood Brown, MD, PhD, UT Southwestern Medical Center

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
February 21, 2019

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
May 28, 2025

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
May 28, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
December 12, 2018

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 2, 2019

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 7, 2019

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
July 9, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 3, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
July 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • STU-2018-0034

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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