Improving Asthma Outcomes and Self-management Behaviors of
Inner-city Children
A Randomized Trial of the Health Buddy
Interactive Device and an Asthma Diary
Sylvia Guendelman, PhD; Kelley Meade, MD; Mindy Benson, PNP; Ying Qing
Chen, PhD; Steven Samuels, PhD
Background Asthma is an important cause of morbidity, absence from school,
and use of health services among children. Computer-based educational programs
can be designed to enhance children's self-management skills and to reduce
adverse outcomes.
Objective To assess the effectiveness of an interactive device programmed
for the management of pediatric asthma.
Design A randomized controlled trial (66 participants were in the
intervention group and 68 were in the control group).
Setting Interventions conducted at home and in an outpatient hospital
clinic.
Participants Inner-city children aged 8 to 16 years diagnosed as having asthma
by a physician.
Intervention An asthma self-management and education program, the Health Buddy,
designed to enable children to assess and monitor their asthma symptoms and
quality of life and to transmit this information to health care providers
(physicians, nurses, or other case managers) through a secure Web site. Control
group participants used an asthma diary.
Main Outcome
Measures Any limitation in
activity was the primary outcome. Secondary outcomes included perceived asthma
symptoms, absence from school, any peak flow reading in the yellow or red zone,
and use of health services.
Results After adjusting for covariates, the odds of having any limitation
in activity during the 90-day trial were significantly (P = .03) lower for children randomized to
the Health Buddy. The intervention group also was significantly (P = .01) less likely to report peak flow
readings in the yellow or red zone or to make urgent calls to the hospital (P = .05). Self-care behaviors, which were
important correlates of asthma outcomes, also improved far more for the
intervention group.
Conclusion Compared with the asthma diary, monitoring asthma symptoms and
functional status with the Health Buddy increases self-management skills and
improves asthma outcomes.
Arch Pediatr Adolesc Med.
2002;156:114-120
ASTHMA IS an important cause of morbidity,
absence from school, and use of health services among children in the United
States. Approximately 4.8 million children have asthma, and prevalence rates
are increasing.1, 2 More and more, asthma
is being considered an "ambulatory care sensitive condition" for
which hospitalizations can be avoided with appropriate and timely outpatient
care.3(p245),4 National guidelines
for clinicians in 19915 and revised in 19976 recommended the use of
written asthma plans, with medications to be initiated or increased for
exacerbations to avoid unnecessary hospitalizations. Additional preventive
interventions7-9 focus on
environmental modifications, such as removing dust mites or reducing cockroach
exposure, while others10-13 are directed at
educating families and achieving behavioral changes and skills management.
Effective management of pediatric asthma requires involvement of children and
their families, who learn to: (1) alter the child's activities and home
environment contingent on the child's particular sensitivities; (2) adjust the
child's medications, depending on the child's physiologic state; and (3)
communicate with the child's clinician to tailor the treatment regimen.6, 14 The National Heart,
Lung, and Blood Institute (NHLBI) recommends that patients monitor their asthma
with a daily diary or a periodic self-assessment sheet before a visit to the
physician to capture their impression of whether the asthma is controlled and
to assess self-management skills.6
Several self-management programs that seek to
enhance the child's and the family's efficacy in asthma care have been
developed. While education programs delivered to parents and children by health
professionals in health care settings can improve asthma management skills,
these programs often imply large expenditures of staff time and operational
challenges.14 Furthermore,
life strains and health care access barriers refrain many poor families from
participating in teaching sessions and finding the time and resources required
to manage asthma.15, 16
More recently, interactive computer-based
educational programs, such as Asthma Command12 and Asthma Control,14 have appeared. Unlike
traditional methods, these programs do not rely on the interaction between the
child and a health professional. Randomized trials12, 14 of these software
programs in clinic settings have demonstrated mixed results in their ability to
affect asthma management behaviors.
Another approach, the use of interactive health
communication devices, through its information and decision support, has the
potential to change behaviors and thereby improve patient quality of life and
reduce the burden of illness.17 These devices work on
the premise that the best method of affecting behaviors is to learn specific
behaviors in a safe and stimulating environment while trying them out in a real
environment.18
We evaluated the efficacy of a new interactive
device, the Health Buddy, programmed for the care of inner-city children with
asthma (children were defined as those aged 8-16 years in this study). This
home-based device monitors asthma symptoms, quality of life, and self-care, and
sends information through a secured Web site to the health care provider
(physicians, nurses, or other case managers). We postulated that by allowing
children an opportunity to acquire knowledge about asthma and symptom
recognition and receive immediate feedback on their decisions and behaviors,
asthma symptoms among Health Buddy users would decrease.18 The continued use of
the Health Buddy would also help to increase self-care behaviors, which in turn
would reduce symptoms.
PARTICIPANTS AND METHODS
SAMPLE AND STUDY PROTOCOL
A randomized controlled trial of a computerized interactive asthma
self-management and education program, the Health Buddy, was conducted in the
primary care clinic at Children's Hospital Oakland, Oakland, Calif. This clinic
is a comprehensive pediatric health center and resident teaching facility that
serves a predominantly Medicaid-insured population. Children were eligible for
inclusion in the study if they were between the ages of 8 and 16 years, had an
English-speaking caregiver, had a telephone at home, and were diagnosed as
having persistent asthma following NHLBI clinical practice guidelines.13 Patients with 2 or
more emergency department (ED) visits and/or at least 1 inpatient admission
during the year before the study were identified for possible recruitment
through hospital administrative lists. All other children were recruited at the
time of their scheduled clinic appointment for either a health care maintenance
or an illness visit, including asthma. Patient lists were reviewed the day
before the clinic appointment, and all children with asthma as the reason for
the visit were screened for study eligibility. Potential recruits were also
referred by the attending physicians at the hospital.
Patients were excluded if they were involved in
other asthma or drug efficacy studies, if they were involved in research that
required behavior modification, or if they had mental or physical challenges
that made it difficult to use the Health Buddy. Children with comorbid
conditions that could affect their quality of life were also excluded.
Approximately 500 children aged 8 to 16 years
attending the clinic had asthma, not necessarily persistent. A screening tool
that included the criteria previously described was used, and 136 children
identified as eligible were approached for participation in the study between
April 8, 1999, and July 5, 2000. Families were told that the purpose of the
study was to find out if keeping track of asthma symptoms at home would help
the families and physicians to manage the child's asthma better and that 2
methods of keeping track were being evaluated. The nurse coordinator (M.B.)
obtained informed consent for 134 children and their parents or legal
guardians. Two families declined to participate because of time constraints.
After consent was given, the nurse conducted a
standardized teaching session in which each participating child was given a
peak flow measuring device and instructed on proper technique and how to
establish his or her personal best. In addition, this teaching session also
covered green-yellow-red zone determination and the appropriate use of
medications and of health care services. Subsequently, the nurse coordinator
administered the baseline questionnaire to the child and the accompanying
family member, and gave each family a $20 incentive for completing the
interview. Following the interview, the nurse opened a sealed envelope
containing the treatment assignment and children were randomized to either the
intervention (n = 66) or the control (n = 68) group and given instructions on
how to use the assigned tracking method to record their peak flow readings and
symptoms. (Sample size calculations were based on a comparison of 2 management
approaches by Lieu et al,13 who observed mean
numbers of episodes of children's cough and other asthma symptoms in the
previous 2 months of 2.43 for intensively treated children and 3.08 for
controls, with a pooled SD of 1.25. To detect a similar difference with 85%
power, a 2-sided 2-sample t test
requires 67 subjects per group.)
INTERVENTION
The Health Buddy is a personal and interactive communication device developed
by Health Hero Network, Mountain View, Calif. The device is connected to a home
telephone and can be programmed to present questions and information on a
screen and to record responses. The nurse coordinator sends a set of queries
each day using a standard Internet browser. The patient answers the queries,
called dialogues, by pressing 1 of 4 buttons. The device automatically telephones
a data processing center at night, which processes the responses and publishes
them to a secure Web site the next day, from which the nurse coordinator
reviews the information. Three of us (S.G., K.M., and M.B.) developed a
protocol with a team of software programmers and asthma specialists at Health
Hero Network. Following the NHLBI clinical practice guidelines,6 the protocol consisted
of 10 questions about asthma symptoms, peak flow readings, use of medications
and of health services, and functional status, such as school attendance and
activity limitations. Each answer to a question received immediate feedback
from the device: praise for a correct answer or encouragement to try again. In
addition to the core inmutable questions, asthma facts and trivia questions,
which changed daily, were included to peak children's curiosity and enhance
learning. The dialogues were designed for a third-grade reading level. The
following excerpt illustrates the dialogue between the child and the Health
Buddy:
Hi! Thanks for hanging out with your Health
Buddy today.
Your questions are now ready for you.
Do you know how much a McDonald's hamburger cost
in 1963? (Trivia)
Have you had any coughing or wheezing in the
last day?
If child answers Yes:
This could be a sign that your asthma is acting
up. You may need to take your Albuterol as directed by your doctor when you are
coughing and wheezing.
If No:
That's great! You must be taking your preventor
[sic] medicine.
Did you miss out on any sports, exercise, or
play yesterday because of your asthma?
If child answers Yes:
Sorry to hear you missed out on some fun. If
your asthma acts up while doing sports, exercise, or play, please talk to your
doctor about this. It is important to know what activities might trigger your
asthma.
If No:
That is fantastic! Sports and exercise are fun
and healthy.
By protocol, children had to access the device
once a day, preferably at a regular time. The children were encouraged to
access and interact with the Health Buddy on their own. Parents were instructed
on its use at the first visit and requested to be available to supervise its
use only when the child indicated a need for help. Before implementation, the
protocol was pilot tested among children of comparable age to the study
children, but of higher socioeconomic status.
The comparison method for monitoring symptoms
was a standard asthma diary.13 The diary allowed
patients to log their symptoms and to monitor peak flow, medication use, and
restricted activity.
Families whose children were assigned to the
Health Buddy were given a demonstration on how to use the device and explained
how to install it at home. The nurse coordinator called those families who
because they had not
installed the device properlywere not transmitting
information through the Web to review the installation instructions. No further
telephone contact was established with the participants other than to schedule
follow-up appointments. All children were asked to return for 2 follow-up
visits at 6 and 12 weeks. At each follow-up visit, families were interviewed by
the nurse coordinator and given a standardized teaching session that reinforced
peak flow measurement, compliance with medicines, and tracking of symptoms.
Families received a participation incentive, and children were asked to hand in
their health diaries. They were also examined by a physician. Medical
management remained at the discretion of the physician and followed NHLBI
guidelines. Because all participants were diagnosed as having persistent asthma
before the study, they were prescribed a daily prevention medication and a
quick-relief medication to use as needed, and were requested to measure peak
flows. Treatment regimens were kept constant between visits and changed at the
follow-up visits only if there was a significant deterioration or improvement
in asthma symptoms.
MEASURES
The measures for this study were obtained from the interviews that the nurse
coordinator conducted with the child and the primary caregiver at each visit.
The questionnaire was designed according to well-validated instruments.19-21 The self-reported
information at the follow-up visits was validated against the nurse's knowledge
of the patients and assisted by a medical record review at the time of the
visit.
The primary outcome measure was limitation in
activity, which referred to the occurrence of restricted physical activity,
such as exercise or play, due to asthma. This measure has been a valid
indicator of functional status in other studies.19
Secondary outcome measures consisted of other
self-reported perceived asthma symptoms in the 14 days before the interview,
any missed school days because of asthma in the 6 weeks before the interview,
any peak flow reading in the red or yellow zone in the 14 days before the
interview, and use of health services because of asthma in the past 6 weeks.
The symptom indicators included the occurrence of chest tightness, coughing,
shortness of breath or wheezing, and trouble sleeping at night as a result of
coughing or wheezing. Peak flow readings in the yellow or red zone were based
on the best of 3 readings obtained by the patient on the peak flow meter, a
measure of the maximum flow rate that can be generated during a forced
expiratory maneuver. Although peak flow meters are criticized because they tend
to measure the amount of obstruction in the larger airways only, and often
compliance with its use is low, they provide the only readily available
objective means of patient monitoring at home.22, 23 Peak flow readings in
the yellow zone (50%-80% of the personal best) indicated that the child's
asthma was not under sufficient control and required additional medication.
Readings in the red zone (<50% of the personal best) signaled a severe
asthma exacerbation. Children were instructed to take daily peak flow
measurements and to record them in their diary.
Use of health services was measured by the
presence of hospital admissions, ED visits, or urgent calls to the hospital.
Self-care behaviors assessed the degree of
compliance with prescribed medications and with the use of the Health Buddy or
asthma diary, as appraised by the main caregiver. These self-care behaviors,
along with the asthma outcomes and demographic characteristics, were assessed
through a 30-minute questionnaire consisting predominantly of close-ended
questions. The questionnaires were administered at baseline and at the 2
follow-up visits at 6 and 12 weeks. In addition, tracking with the Health Buddy
or asthma diary was recorded by each child. At baseline, children were
classified according to NHLBI practice guidelines into mild persistent, moderate
persistent, or severe persistent asthmatic categories. These levels of asthma
severity are based on symptom frequency and severity, exercise tolerance, ED
visits, hospitalizations, and current medications.13
DATA ANALYSIS
2
Tests, Fisher exact tests, and 2-sample t
tests were used to compare the 2 study groups for demographic characteristics
(at baseline), asthma outcomes, and self-care behaviors at baseline and at the
2 follow-up visits. Logistic regression was used to model the main effects of
treatment. The results with P
.05 were justified as
significant. Because observations at the 2 follow-up visits were not
independent, the technique of generalized estimating equations24 was used to estimate
treatment effects. For each outcome, the baseline results, the asthma severity
score, and the visit were included as covariates. The effect is presented as
the intervention odds ratio, which is the ratio of odds of an outcome in the
Health Buddy group to the odds of the same outcome in the asthma diary group,
adjusted for visit, baseline responses, and asthma severity. A generalized
estimating equation was also used to evaluate the effects of self-care
behaviors on selected asthma outcomes, adjusted for visit, other behaviors, and
treatment effects. Interaction terms between treatment and time were evaluated
for all outcomes. Missing data were handled by assuming missing at random.25
RESULTS
The Health Buddy and asthma diary groups had
similar demographic characteristics, illness history, home environment, and use
of health services at baseline, as expected from the random assignment (Table 1).
Follow-up of participants occurred similarly across all 4 seasons in the 2
groups. Ninety-six percent of the participants (63 in the Health Buddy group
and 65 in the asthma diary group) returned for the first follow-up visit at 6
weeks and 91% (62 in the Health Buddy group and 60 in the asthma diary group)
returned for the follow-up visit at 12 weeks. Reasons for dropping out of the
study included moving out of the area (n = 3) or life crises experiences (n =
4). Five families who dropped out were unavailable for contact. Baseline
characteristics of children who did and did not complete the trial did not
differ.
Children in both arms of the study reported a
decrease in asthma symptoms and a decrease in peak flow readings in the yellow
or red zone at 6 and 12 weeks compared with baseline (Table 2).
Although almost half of the children did not use a peak flow device at
baseline, at the 6-week follow-up visit, 85% of the participants reported that
they used it. Significantly fewer children randomized to the Health Buddy had
peak flow readings in the yellow or red zone during the 14 days before the
6-week follow-up visit compared with children randomized to the asthma diary (P = .02).
After adjusting for time and baseline
covariates, children in the Health Buddy group were less likely to report
limitation in activities. Furthermore, the odds of having peak flow readings in
the yellow or red zone were significantly lower for children randomized to the
Health Buddy.
The use of health services did not vary
significantly between the 2 groups, except for urgent calls. The odds of an
urgent call with the Health Buddy was 0.43 of the odds of an urgent call with
the asthma diary, after adjusting for time and baseline covariates (Table 3).
No significant interactions between treatment and time were found for any
outcome.
For self-care behaviors, at 12 weeks children
with the Health Buddy were significantly more likely to take asthma medicines
without reminders (P = .04) and
to use the Health Buddy with few or no reminders (P = .001) (Table 4).
These self-care behaviors were significant correlates of asthma outcomes after
adjusting for treatment effects, time, and other self-care behaviors (data not
shown). Children who always used the Health Buddy or the asthma diary without a
reminder were significantly less likely to report coughing or wheezing (odds
ratio, 0.70; 95% confidence interval, 0.50-0.99) and had a lower probability of
having a limitation in activities (odds ratio, 0.70; 95% confidence interval,
0.50-0.90).
On average, during the 90-day trial period, 77%
of the children used their tracking system 3 days a week or more (59 [89%] of
the 66 children in the Health Buddy group vs 44 [65%] of the 68 children in the
asthma diary group; P<.001).
The daily compliance rates declined as time progressed for both treatment arms,
but the decline was faster in the early stages of the intervention for the
asthma diary group (P = .0004,
data not shown). An analysis of time effects adjusted for treatment assignment
(data not shown) indicated that asthma symptoms and use of health services
declined markedly from one visit to the next for both groups.
We found no strong indication that the
correlation between asthma diary and Health Buddy responses and interview
responses differed between the 2 study groups. However, responses across visits
seemed to be more stable for the Health Buddy group.
COMMENT
This randomized trial conducted in an inner-city
ambulatory care clinic assessed the efficacy of the Health Buddy for
self-management of persistent asthma in children. We compared the effects of
this device, which is a nonintrusive interactive system that linked patients at
home to the nurse coordinator, with the effects of the standard asthma diary.
One of the goals of asthma control is to be free
of activity limitation. Children randomized to the Health Buddy had 48% lower
odds of reporting a limitation in activity after adjusting for baseline
response, asthma severity, and time. Children randomized to the Health Buddy
also had significantly lower odds of reporting a peak flow reading below 80% of
their personal best (red or yellow zone) after adjusting for covariates.
Despite missing data for this outcome, especially among children in the asthma
diary group, the higher rate of children with peak flow readings remaining in
the green zone among Health Buddy users is an indicator of improved control of
asthma symptoms and improved response to anti-inflammatory therapy. Spirometry
was not available for the study.
The percentage of children randomized to the
Health Buddy who used the device was, until near the end of the study, much
larger than the percentage of children who kept diaries. This leads to the
following question: Was self-monitoring, per se, associated with improved
outcomes? The analysis of this question does not benefit from randomization.
Children who used the Health Buddy or asthma diaries with few or no reminders
were far less likely to report coughing or wheezing and to have a limitation in
activities.
Several children reported after the trial that
they liked the Health Buddy because it was fun and it reminded them to take
their medicines. In contrast, several children who received the asthma diary
reported that they either lost it or forgot to log information in it. Many
children who kept diaries reported that they had forgotten to take their
medicines. These results occurred despite the decline in Health Buddy use and
suggest that children with the Health Buddy device learned management skills
that helped them to comply with their treatment and medication regimens.
The short duration of the trial and the small
sample size did not yield marked group differences in the occurrence of ED
visits or hospital admissions. However, after adjusting for time, asthma
severity, and urgent calls before the baseline interview, the risk of urgent
calls was twice as high for children assigned to the asthma diary group. This
finding would suggest a weaker autonomy in the management of asthma for the
child and the family assigned to the control arm of the study.
Despite the marked advantages of the Health
Buddy monitoring system over the standard asthma diary, use in both groups
declined as children approached the end of the trial. These declines probably
reflect the anticipated end of the study, the lack of perceived additional
benefit of monitoring, and, for Health Buddy users, saturation with the
educational messages. This trend would suggest that the benefits of
self-monitoring with a device like the Health Buddy might be especially strong
at critical care management times (eg, at the start of care for asthma or after
an acute asthma exacerbation, an ED visit, a hospitalization, or a step up in
severity class).
Although asthma symptoms declined more for the
Health Buddy group, symptoms also declined for the asthma diary group. This
decline may have partly resulted from the consistent standardized asthma
education given to children in both arms of the study and the availability of
the nurse coordinator, which was a new intervention to the clinic. Furthermore,
because this intervention took place shortly after dissemination of the revised
NHLBI asthma guidelines, the findings may reflect enhanced care by the hospital
staff resulting from adherence to these guidelines.
The results must be interpreted with caution
given the study limitations. Despite the attempts by the nurse coordinator to
check the self-reported data at each interview, there may have been some case
ascertainment bias. Furthermore, children in the asthma diary group who filled
out diaries retrospectively may have overstated compliance. In addition, some
of the results were leaning toward significance, suggesting that there might
have been a lack of power to detect significant differences because of a small
sample size. Further research is needed to assess the effects of this device on
the behavior of health care providers. At the time of the study, implementation
graphs and other data outputs were not readily or consistently available for
providers. The system now has the capacity to summarize longitudinally patient
data on symptoms, health behaviors, and knowledge levels. Research is also
warranted to evaluate individual differences in self-management skills,
outcomes, and saturation points associated with Health Buddy use among
inner-city children. A longer follow-up study could determine whether changes
in asthma self-care behaviors and symptoms persist over time. The cost of using
the Health Buddy technology and service consists of one-time implementation
fees and patient activation fees, which vary by disease and by patient volume.
The average monthly cost per patient ranges from $20 to $45. Additional costs
involve the case manager and depend on caseload. A cost-effectiveness analysis
focusing on ED visits, hospitalizations, and other burdens to the health care
system would help to determine if the extra expense of the computer telephone
system is worth the observed improvement vs close follow-up by the nurse case
manager alone. Nevertheless, the significant group effects in self-care
behaviors and asthma outcomes found with the Health Buddy suggest that such easy-to-use
devices empower children to provide more of their own care, while perhaps
reducing the burden of illness on the family and on the health care system.
Author/Article Information
From the Maternal and Child Health Program (Drs Guendelman and Samuels), the
Division of Health Policy and Management (Dr Guendelman), and the Division of
Biostatistics (Dr Chen), School of Public Health, University of California,
Berkeley; and Ambulatory Services, Children's Hospital Oakland, Oakland, Calif
(Dr Meade and Ms Benson).
Corresponding author and reprints: Sylvia Guendelman, PhD, Division of Health
Policy and Management, University of California, Berkeley, 404 Earl Warren
Hall, 7360, Berkeley, CA 94720-7360 (e-mail: [log in to unmask]).
Accepted for publication October 18, 2001.
This study was supported in part by an
unrestricted educational grant from Health Management Services, Merck & Co,
Inc, Whitehouse Station, NJ.
We thank Scott Hambly and Mara Sanderson for
their clerical support.
|
What
This Study Adds Several programs that seek to enhance efficacy
in self-management have been developed in asthma care. Randomized trials of
computer-based educational programs conducted in clinic settings have
demonstrated mixed results in their ability to affect asthma management
behaviors. We evaluated the efficacy of a new home-based interactive health
communication device, the Health Buddy, that was designed to enable children
to assess and monitor their asthma symptoms and quality of life and to
transmit this information to a case manager through a secure Web site. This
study presents the results of a randomized, controlled, 90-day clinical trial
of inner-city children with persistent asthma. Compared with children
assigned to an asthma diary, children randomized to the Health Buddy were
more likely to improve self-care behaviors and to reduce asthma symptoms,
while making fewer urgent calls to the hospital, after adjusting for other
factors. Easy-to-use Web-based devices such as the Health Buddy may be useful
tools to empower children to provide their own care while reducing asthma
symptoms and health care use in pediatric settings. |
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