Background
Ischemic heart disease (IHD) is the leading cause of death in the United States.
1
Cardiac rehabilitation is an evidence‐based, cost‐effective, multidisciplinary program
of individual patient risk factor assessment and management, exercise training, and
psychosocial support for patients with heart disease that reduces mortality by 12%
to 34% (Table 1).
2–6
Cardiac rehabilitation is recommended by American Heart Association (AHA) and the
American College of Cardiology (ACC) Guidelines for patients after myocardial infarction
(MI), percutaneous coronary intervention (PCI), or coronary artery bypass surgery
(CABG).
7
However, cardiac rehabilitation is dramatically underutilized, with only 14% to 31%
of eligible patients participating.
8
Barriers to participation include low referral rates, patient difficulty attending
center‐based rehabilitation sessions, and cost.
9
Recently, an AHA Presidential Advisory called for a reengineering of cardiac rehabilitation
to enhance access, adherence, and effectiveness.
10
It is clear that new strategies are needed for the delivery of cardiac rehabilitation.
Table 1.
Core Components of Cardiac Rehabilitation
2–3
1. Patient assessment
2. Nutritional counseling
3. Weight management
4. Blood pressure management
5. Lipid management
6. Diabetes management
7. Tobacco cessation
8. Psychosocial management
9. Physical activity counseling
10. Exercise training
Mobile technology has the potential to overcome barriers to access to cardiac rehabilitation
and may be a useful tool for increasing participation. Mobile health provides the
opportunity to improve access to health promotion interventions and has the unique
advantage of being able to influence health behaviors in real‐time.
11
Of smartphone users, 86% have used their mobile phone to access just‐in‐time information
in the past month.
12
Through mobile technology, a user can receive and interact with information, record
and review data, receive automated feedback, and connect with other users or healthcare
providers.
Mobile health interventions also have the potential to reach a wide segment of the
population. Among American adults, 91% own a mobile phone and 56% own a smartphone.
13
Mobile health applications are increasingly popular, with ≈1 in 5 smartphone users
having downloaded a mobile health application.
14
Among minorities, a group with traditionally low participation in cardiac rehabilitation,
evidence suggests that uptake of smartphones is high, and that minorities are more
likely than nonminority populations to use their smartphones to access health information.
13–14
In addition, those without home broadband internet access are using their smartphones
to access the internet, suggesting that the mobile platform could have even greater
penetration than a purely internet‐based platform for reaching disadvantaged populations.
15
While older adults are less likely than younger adults to use mobile technology, recent
trends have shown significant increases in internet use and mobile phone ownership
by older adults.
14,16
Use of mobile phone applications can increase motivation and physical activity in
generally healthy populations.
17–18
Studies of mobile applications have shown a high degree of acceptability and reasonable
efficacy for increasing physical activity and weight loss. In patients with diabetes,
mobile applications for self‐management have been shown to improve blood glucose control.
19
These findings raise the possibility that mobile applications could be used for promoting
physical activity and self‐management among patients with IHD who are eligible for
cardiac rehabilitation.
However, little is known regarding the use of mobile applications for cardiac rehabilitation.
As these mobile applications begin to emerge, it will be important to have a standard
framework for their evaluation. In this review, we examine the existing literature
on the use of mobile technology for cardiac rehabilitation and propose a framework
for developing and evaluating mobile applications for cardiac rehabilitation.
Literature Search
We performed a PubMed search from January 1, 1993 to September 2, 2013 for relevant
articles using the following search strategy: (“telemedicine”[Mesh] OR mobile OR internet
OR web OR smartphone OR mHealth OR eHealth) AND (“cardiac rehabilitation” OR [{cardiac
OR cardiovascular OR heart} AND “secondary prevention”]). The search returned 150
studies. One author (A.B.) reviewed the abstracts of all articles for inclusion and
exclusion criteria. Included studies were those that involved mobile phone interventions
for cardiac rehabilitation for patients with IHD. Protocols and completed studies
were eligible for inclusion. Studies were excluded from this review if they were not
available in English, did not include an intervention with evaluation of health outcomes,
did not have a mobile phone component, did not enroll adult patients with IHD, or
did not have a physical activity component (Figure). Articles reporting content and
technical development of included studies were noted. Review articles were excluded
from the analysis, but references were examined for other articles meeting inclusion
and exclusion criteria. References of included studies were also reviewed to identify
other articles meeting inclusion and exclusion criteria.
Figure 1.
Flow diagram of literature search and selection of studies for review. IHD indicates
ischemic heart disease.
Existing Studies
We identified 3 completed, published studies involving mobile phone technology for
the delivery of cardiac rehabilitation that evaluated health outcomes in patients
with IHD (Table 2).
20–22
Though relatively small and not explicitly based on behavior change theory, these
studies supported the feasibility and acceptability of the use of mobile technology
for cardiac rehabilitation. No studies have evaluated efficacy with regard to cardiovascular
events. However, several groups of investigators have published promising study designs
for evaluating the use of mobile technology for delivery of cardiac rehabilitation
(Table 3).
23–26
These studies expand on the existing literature by including the core components of
cardiac rehabilitation, basing their interventions on behavior change theory, evaluating
a wide array of patient‐centered health outcomes, and employing randomized clinical
trial designs (to reduce bias due to confounding from baseline differences in mobile
versus traditional groups).
Table 2.
Completed Studies of Mobile Technology for Cardiac Rehabilitation for Ischemic Heart
Disease
Author/Year/Country
Design/Duration
Theoretical Foundation
Non‐mHealth Components
mHealth Components
Intervention
Control
Outcomes
Worringham
20
2011Australia
Observational6 weeks
None
Telephone contact pre‐ and postexercise session with provider.
Smartphone, smartphone application, single‐lead ECG, GPS with real‐time transmission
to providers.
Monitored exercise training (walking) 3 times weekly assisted by smartphone application.
(N=6)
None
Usability: 80% of sessions no technical problems. Ease of use rated 4.8/5 (95% CI
4.6 to 5.0).
Participation: Completed 80% of scheduled exercise sessions.
Exercise Capacity: 6MWT improved from 524 to 637 m (P=0.009).
Health Status: SF36 Physical Health increased from 50.0 to 78.4 (P=0.03), Mental Health
unchanged.
Events: None
Korzeniowska‐Kubacka
21
2011Poland
Nonrandomized clinical trial8 weeks
None
Supervised exercise sessions at outpatient clinic.No additional intervention specified
as adjunct to home sessions.
Mobile device with preprogrammed exercise training sessions with audio and visual
cues for training intensity and 3‐lead ECG monitor. Data transmitted via mobile phone.
10 clinic supervised exercise sessions followed by 14 home exercise sessions with
mobile application (3 sessions per week). (N=30)
24 clinic supervised exercise sessions (3 sessions per week). (N=32)
Exercise Capacity: 17.6±16.1% improvement mobile vs 11.5±35.9% control (P>0.05).
Risk Factors: BP not significantly changed in either group.
Events: not reported
Blasco
22
2012Spain
RCT12 months
None
In person assessment. Lifestyle counseling.Intervention participants also supplied
with blood pressure cuff, glucose and lipid meter as well as education on use.
Mobile phone with structured questionnaires for entry and transmission of blood pressure,
heart rate, weight, glucose, and lipids. SMS messaging of recommendations.
Lifestyle counseling, mobile intervention, devices for home monitoring. (N=102)
Lifestyle counseling (N=101)
Usability: mHealth group completed 89% of entries. 5/102 dropped out due to difficulty
with mHealth intervention.
Physical Activity: 75% met goals in mHealth group vs 73% control.
Risk Factors: mHealth group more likely to improve at least 1 risk factor kor (RR
1.4, 95% CI 1.1 to 1.7) (primary outcome). mHealth group more likely to achieve goals
for BP (62.1% vs 42.9%), hemoglobin A1c (86.4% vs 54.2%), and BMI (0.37 kg/m2 decrease
vs 0.38 increase). No significant differences in smoking cessation, cholesterol, medication
adherence.
Events: 5 deaths in control group, 0 in mHealth group
6MWT indicates 6‐minute walk test; CI, confidence interval; BMI, body mass index;
BP, blood pressure; ECG, electrocardiogram; GPS, global positioning system; RCT, randomized
clinical trial; RR, relative risk; SF‐36, short form 36; SMS, short message service.
Table 3.
Ongoing Studies of Mobile Technology for Cardiac Rehabilitation for Ischemic Heart
Disease
Author/Year/Country
Design/Duration
Theoretical Foundation
Non‐mHealth Components
mHealth Components
Intervention
Control
Outcomes
Walters
23
2010Australia
RCT6 weeks (intensive)6 months (follow‐up)
None
In‐person assessment. Individual goal setting with Mentor. Weekly mentoring sessions.
Recommendation for walking‐based exercise program.
Smartphone application with step counting, goal setting, diaries (weight, blood pressure,
physical activity), visual feedback, text message reminders, educational videos, web
portal. Subset will also have ECG and HR monitoring.
Smartphone application plus counseling (N=100).Smartphone application with ECG and
HR monitoring plus counseling (N=15)
Outpatient center‐based CR (N=100)
Usability: survey
Participation: dropout rates
Physical Activity: self‐reported and objectively measured (primary outcome).
Exercise Capacity: 6MWT
Risk Factors: BMI, BP, smoking, alcohol, lipids, HbA1c, med adherence, Diet habits
questionnaire
Health Status: EQ‐5D, Health Outcome Questionnaire, SAQ, Psychologic functioning
Cost: facility, technology, return‐to‐work
Events: hospitalizations and death
Maddison
24
2011New Zealand
RCT24 weeks
Self‐efficacy Theory
In‐person assessment and exercise prescription. Pedometer provided. Web portal for
entry of physical activity, viewing videos, educational material.
SMS messages (personalized) for behavioral support to promote self‐efficacy.
In‐person assessment, personalized SMS messages and web portal. (N=85)
Referral to community‐based CR. (N=85)
Participation: defined as at least 1 exercise session
Physical Activity: IPAQ, Phone diary
Exercise Capacity: Treadmill VO2max (primary outcome), 6MWT.
Risk Factors: BMI, waist and hip circumference, BP
Health Status: self‐efficacy, SF‐36, EQ‐5D
Cost: program and medical
Events: illness, signs and symptoms
Antypas
25
2012Norway
Cluster RCT1 year
Self‐efficacy, Health Action Process Approach, Stages of Change
Completion of 4‐week center‐based CR program. Internet‐based self‐management program.
Enhanced version includes tailoring of content and messages.
SMS reminder messages to fill out questionnaires.
Enhanced version of internet‐based self management program. (N=8 clusters of 15 each)
Internet‐based self management program. (N=8 clusters of 15 each)
Usability: log‐in data, evaluation
Physical Activity: IPAQ (primary outcome)
Risk Factors: smoking, alcohol use
Health Status: self‐efficacy, Hosptial Anxiety and Depression, social support, EQ‐5D
Costs: return‐to‐work
Alsaleh
26
2012Jordan
RCT6 months
Social Cognitive Theory, Self‐efficacy Theory
In‐person assessment and advice for CR. Physical activity diary.
Personalized SMS motivational messages (1/week×3 months then 1/2 weeks×3 months).
Personalized program and SMS messages. (N=71)
Advice from providers on physical activity. (N=85)
Usability: evaluation survey
Physical Activity: IPAQ (primary outcome)
Health Status: self‐efficacy, Mac‐New Heart Disease Questionnaire
6MWT, 6‐minute walk test; BP, blood pressure; BMI, body mass index; CR, cardiac rehabilitation;
ECG, electrocardiogram; EQ‐5D, European quality of life—5 dimensions; HR, heart rate;
IPAQ, International Physical Activity Questionnaire; RCT, randomized clinical trial;
SAQ, Seattle Angina Questionnaire; SF‐36, short form 36; SMS, short message service.
Proposed Framework
Although mobile health applications are increasingly prevalent, they are often not
based on evidence‐based practices or rigorously studied with regard to their impact
on health outcomes.
11,27–30
Based on data from the completed and ongoing studies of the use of mobile technology
for cardiac rehabilitation, as well as the principles for establishing evidence for
mobile health applications,
27,30
we propose a framework for the development and evaluation of mobile applications for
cardiac rehabilitation for patients with IHD (Table 4). The design of the mobile application
should address the core components of cardiac rehabilitation, be based on behavior
change theory, provide tailoring of the mobile application to the individual, and
be highly usable. The evaluation of the mobile application should include rigorous
study with a randomized clinical trial design comparing the mobile application to
usual care and assessment of important patient‐centered outcomes. In addition, the
design and reporting of clinical studies of mobile applications for cardiac rehabilitation
should adhere to the CONSORT (Consolidated Standards Of Reporting Trials) guidelines
for mobile health interventions.
31
Table 4.
Framework for Evaluating Mobile Applications for Cardiac Rehabilitation
1. Address core components of cardiac rehabilitation:
● Patient assessment
● Exercise training
● Self management, may include:
○ Physical activity
○ Diet
○ Medication adherence
○ Smoking
● Psychosocial Support
2. Apply behavior change theory
3. Enable individual tailoring of features
4. Demonstrate high usability
5. Improve patient‐centered outcomes:
● Participation in cardiac rehabilitation
● Physical activity (energy expenditure)
● Exercise capacity
● Cardiovascular risk factors (nutrition, weight, blood pressure, cholesterol, diabetes,
tobacco use)
● Patient‐reported health status (symptoms, functional status, quality of life)
● Cost
● Cardiovascular events
6. Establish efficacy in a randomized clinical trial
Core Components of Cardiac Rehabilitation
The American Association of Cardiovascular and Pulmonary Rehabilitation specifies
several key components that should be included in a cardiac rehabilitation program
(Table 1).
2–3
However, the optimal components necessary to maximize the effectiveness of cardiac
rehabilitation and simplicity of delivery are not entirely clear. Similar mortality
benefits have been observed with education plus counseling, exercise training alone,
and exercise training combined with additional interventions.
4,32
A recent systematic review of alternative approaches to the delivery of cardiac rehabilitation
concluded that (1) the most effective interventions combined individual patient risk
factor management with psychosocial support, and (2) there was insufficient evidence
to support interventions based solely on exercise training.
33
Naturally, healthcare providers expect that technology‐based cardiac rehabilitation
will include similar components to traditional cardiac rehabilitation and occur in
the context of supervision by a healthcare provider.
34
However, only one published study of mobile technology for cardiac rehabilitation
has included components other than exercise training. Ongoing studies plan to evaluate
a more comprehensive program of cardiac rehabilitation.
Based on these findings, we suggest that mobile technology‐based interventions for
cardiac rehabilitation should include individual patient risk factor assessment and
management, exercise training, self‐management of modifiable risk factors, and psychosocial
support. Since the optimal combination of core components for mobile‐delivered cardiac
rehabilitation is unknown, this represents an important area for future research.
Theoretical Foundation for Behavior Change
Cardiac rehabilitation can be considered a behavior change intervention to promote
healthy behaviors in patients with IHD. Interventions that are based on behavior change
theory are more effective than those lacking a theoretical basis.
35–36
To date, published studies of mobile cardiac rehabilitation have not specifically
addressed behavior change strategies in their design. However, several of the ongoing
studies specifically incorporate behavior change strategies, including short‐ and
long‐term goal setting,
23–24,26
motivational messages and reminders,
23,25–26
application of behavior change theories,
24–26
and attention to promoting self‐efficacy.
24–26
Attention to principles from behavior change theories in the design of mobile interventions
for cardiac rehabilitation may significantly increase the likelihood of success. In
addition, mobile technology may provide an opportunity for delivering real‐time cues
to promote behavior change.
11
Individual Tailoring
Content development studies of mobile‐ and web‐based cardiac rehabilitation support
designing the intervention to be tailored to the individual.
34,37
Both web‐ and mobile‐based systems offer the opportunity to remotely provide programmed
feedback based on individually set preferences, short‐ and long‐term goals, and personally
tailored feedback from a cardiac rehabilitation provider. However, it appears that
access and participation may be superior via a mobile platform.
38
All published and planned studies of the use of mobile technology for cardiac rehabilitation
include some degree of tailoring the intervention to the individual, further highlighting
the importance of tailoring in the design of mobile interventions for cardiac rehabilitation.
Usability
An easy‐to‐use interface is a desired feature of mobile applications for promoting
physical activity.
37,39
Ongoing studies suggest that mobile applications for cardiac rehabilitation can be
highly usable, and that use may be promoted by automatic (preferably wireless) entry
of data, such as objectively‐measured physical activity.
38
Further study is needed on the features of mobile phone applications for cardiac rehabilitation
that promote usability, including the need for integration of sensors for ECG monitoring,
physical activity monitoring (via accelerometer and global positioning system [GPS]),
and measurement of heart rate, blood pressure, and blood glucose. We propose that
formal evaluation of the usability of the mobile application be conducted with user‐testing
and field studies to evaluate qualitative and quantitative measures of efficiency,
effectiveness, and user satisfaction.
40–41
Patient‐Centered Outcomes
Historically, the evaluation of cardiovascular disease interventions has focused on
hard cardiovascular events such as death, myocardial infarction, heart failure, and
stroke. However, it has become increasingly important to evaluate interventions in
the context of patient‐centered outcomes.
42–43
Patient‐reported health status includes symptoms, functional status, and health‐related
quality of life. These outcomes are influenced by physical, mental, and social health.
44
In patients with IHD, there are significant variations in health‐related quality of
life, even at similar severity of symptoms.
45
Thus, the impact of a mobile application on health outcomes must be examined at multiple
levels, including participation in cardiac rehabilitation sessions,
46–47
physical activity, exercise capacity, cardiovascular risk factors, patient‐reported
health status, costs, and clinical events.
Physical activity reduces risk of secondary cardiovascular events in patients with
IHD.
48–49
Although patient recall is a common method for evaluating physical activity, it is
not as accurate as real‐time reporting of physical activity.
50–51
The use of mobile technology offers a promising alternative to traditional recall‐based
physical activity questionnaires because physical activity can be reported in real‐time
through the mobile device. In one study, mobile‐reported physical activity correlated
with both objectively‐measured physical activity and self‐reported physical activity,
but there was a large degree of variability in mobile‐reported physical activity at
similar levels of objectively‐measured activity.
52
Furthermore, mobile technology offers the possibility of interfacing with accelerometers,
pedometers, and other wireless devices that track physical activity.
Exercise capacity is also protective against cardiovascular events in patients with
IHD.
53–57
Measurement of exercise capacity can be undertaken through a variety of methods, including
cardiopulmonary exercise testing with expired gas measurement and treadmill exercise
testing. The 6‐minute walk test, a test of functional exercise capacity, predicts
cardiovascular events similarly to treadmill exercise testing, and offers a simple
and less resource‐intensive method for measuring exercise capacity.
53
Using mobile technology, patients could conduct their own 6‐minute walk test through
device‐based sensors (eg, GPS). Moreover, these measurements could be further integrated
with other peripheral sensors (eg, measurement of ECG, heart rate, blood pressure,
weight, blood glucose, and more), and with ecologic momentary assessment of behavioral
and cognitive phenomena. Future research should include evaluation of the reliability
and validity of sensors and ecologic momentary assessment for measuring health outcomes
associated with mobile technology.
Cardiac rehabilitation is a cost‐effective intervention for patients with IHD.
5
It is unclear what the impact of the use of mobile technology will be on overall costs
of care. Although mobile devices and wireless services are expensive, potential savings
may include lower travel costs, fewer lost wages, and reduced rates of rehospitalization.
Insights gained from the impact of mobile technology on health status may help tailor
cardiac rehabilitation to the needs of the individual and ultimately decrease risk
of secondary events in patients with IHD.
Efficacy in Randomized Clinical Trial
While observational studies and the analysis of observational data provide important
insights about treatment effects, the gold standard for establishing efficacy remains
the randomized clinical trial. Of the published studies on the use of mobile technology
for cardiac rehabilitation, only 1 employed a randomized design, comparing the mobile
intervention to standard risk factor counseling alone.
22
Ongoing studies are planning randomized or cluster‐randomized designs, which may provide
evidence on the efficacy of mobile interventions for cardiac rehabilitation.
23–26
An important consideration in randomized study design is the selection of a comparison
group. Since cardiac rehabilitation reduces mortality and is a guideline‐recommended
therapy, studies comparing the use of a mobile intervention to no intervention would
pose ethical questions. However, standard practices and utilization of cardiac rehabilitation
vary from country to country and region to region, creating a practical challenge
for standardizing a comparison group. Thus, we recommend that studies of mobile interventions
for cardiac rehabilitation be compared with best practices in the setting where the
study is being conducted, preferably with referral to formal center‐based or home‐based
cardiac rehabilitation, since these interventions have established efficacy.
4,6
Conclusions
New strategies for promoting participation in cardiac rehabilitation are desperately
needed. Initial evidence supports the feasibility and acceptability of using mobile
technology for cardiac rehabilitation in patients with IHD. Whether using mobile technology
for cardiac rehabilitation can achieve its potential to improve access, increase participation,
and ultimately improve outcomes in patients with IHD, remains to be seen.