To Determine the Validity of the ACT in an Adolescent Population With Persistent Asthma

Asthma is the most common chronic illness of childhood, and adolescents represent a group
that is typically difficult to engage in self-management strategies. Adolescent asthmatics
tend to have poor perception of symptoms and experience a higher rate of asthma deaths
compared to younger children. Studies have shown that perceived severity of asthma symptoms
is related to self-management in adolescents, who were less likely to receive appropriate
treatment for asthma exacerbation's. This poor perception of asthma control is likely one
cause of the disproportionate asthma mortality rates seen in adolescent patients.

Because asthma control is now the focus of asthma care, assessment of control is the critical
step in appropriate management. The two domains of asthma control, impairment and risk,
evaluate the role asthma plays in a patient's quality of life and functional capacity on an
ongoing basis and the risk their asthma presents for future adverse events. Although the
National Asthma Education and Prevention Program guidelines contain a rubric for asthma
control based on these domains, thus representing the "gold standard" for asthma care, their
utilization may be time-consuming and cumbersome to implement in primary care offices, and
primary care providers may be unfamiliar with their use. For primary care practices following
adolescent patients, it remains imperative that the tools being used to gauge asthma control
be evaluated and validated in this at-risk population.

At this time, there are approximately 17 questionnaires available for use in the assessment
of asthma control, although most are not well validated. Of these, the most widely validated
and most commonly used instrument is the Asthma Control Test (ACT). The ACT is a
self-administered questionnaire intended to assess the impairment domain over the past four
weeks and is completed by patients starting at age 12 years. The ACT has five questions with
an overall best score of 25. For primarily adult Caucasian populations, the ACT has been
found to be a valid, reliable, and responsive instrument of asthma control, and cut-offs for
controlled and not well controlled asthma (< 19) as well as minimal clinically important
(MIC) differences (3 points) have been identified. The measurement properties of validity,
reliability, and responsiveness are critical to the usefulness of any questionnaire in both
clinical and research settings. However, measurement properties of the ACT are lacking in the
adolescent asthma population.The landmark validation study for the ACT by Schatz et al was
comprised of a large sample size of over 300 patients that showed that a cut-off score of 19
as distinguishing well-controlled versus not well-controlled asthmatics. However, the mean
age was 35 for that study population, and concerns have been raised as to whether this
cut-off is appropriate for adolescents in general. Recent studies examining use of the ACT in
Caucasian and Hispanic adolescent populations have found higher optimal cut points to
distinguish control classifications.

Lung function measures are included in the rubric of assessing asthma control by the NAEPP
(National Asthma Education and Prevention Program). Per these recommendations, spirometry
should be available to physicians caring for asthma patients and used with initiation of
treatment, change in asthma control, and every one to two years. While sub-specialists often
have access to spirometry, office-based spirometry is time-consuming, requires technical
ability and staff training, equipment maintenance and calibration, and is not always
available or feasible for use in primary care physician offices. Because spirometry may be of
limited accessibility to primary care providers, questionnaires are quickly taking a leading
role in asthma management. Studies of adolescent asthmatics reveal poor perception of asthma
control leading to under-reporting of asthma symptoms and thus under-treatment of
exacerbation's. This type of under-reporting reflects a false level of asthma control when
queried by the ACT and leads to inappropriate medical management when spirometry is not
utilized.

As exploratory endpoints, we will obtain fractional exhaled nitric oxide (FeNO) measurements
shortly after spirometry is performed. Elevated FeNO indicates eosinophilic airway
inflammation and assists in assigning the correct asthma phenotype, which can have
implications for asthma management. We will also obtain nasal epithelial lining fluid (ELF)
for collection of nasal cytokines and chemokines. This information is useful for expanding
our current understanding of the inflammatory mediators involved in asthma-associated airway
inflammation.

Inclusion Criteria:

- Physician diagnosis of persistent asthma

- Current treatment with appropriate therapy for persistent asthma symptoms per the
NHLBI guidelines including daily controller medication with at least low dose inhaled
corticosteroids

- Must live within convenient driving distance of the North Carolina Children's
Specialty Clinic in Raleigh North Carolina or the EPA Human Studies Facility on
University of North Carolina Campus in Chapel Hill North Carolina.

Exclusion Criteria:

- Unable to perform spirometry

- Other medical history or underlying health problems that would preclude participation.