Abstract
Purpose
Only 34% of breast cancer survivors engage in the recommended level of physical activity because of a lack of accountability and motivation. Methodist Hospital Cancer Health Application (MOCHA) is a smartphone tool created specifically for self-reinforcement for patients with cancer through the daily accounting of activity and nutrition and direct interaction with clinical dietitians. We hypothesize that use of MOCHA will improve the accountability of breast cancer survivors and help them reach their personalized goals.
Patients and Methods
Women with stages I to III breast cancer who were at least 6 months post–active treatment with a body mass index (BMI) greater than 25 kg/m2 were enrolled in a 4-week feasibility trial. The primary objective was to demonstrate adherence during weeks 2 and 3 of the 4-week study period (14 days total). The secondary objective was to determine the usability of MOCHA according to the system usability scale. The exploratory objective was to determine weight loss and dietitian-participant interaction.
Results
We enrolled 33 breast cancer survivors who had an average BMI of 31.6 kg/m2. Twenty-five survivors completed the study, and the average number of daily uses was approximately 3.5 (range, 0 to 12) times/day; participants lost an average of 2 lbs (+4 lbs to −10.6 lbs). The average score of usability (the second objective) was 77.4, which was greater than the acceptable level. More than 90% of patients found MOCHA easy to navigate, and 84% were motivated to use MOCHA daily.
Conclusion
This study emphasizes the importance of technology use to improve goal adherence for patients by providing real-time feedback and accountability with the health care team. MOCHA focuses on the engagement of the health care team and is integrated into clinical workflow. Future directions will use MOCHA in a long-term behavior modification study.
INTRODUCTION
According to the American Cancer Society, there are more than 3.1 million breast cancer survivors, and this number is expected to increase.1 As the 5-year survival trend continues to increase to more than 90%, it is more important now to develop comprehensive survivorship plans.2 Breast cancers survivors are more likely to gain weight after they receive chemotherapy.3-5 This unintentional weight gain over time can lead to obesity and its comorbidities, which include increased risk of cancer recurrence and morbidity.6 More than 50% of breast cancer survivors can be classified as being overweight (body mass index [BMI] > 25 kg/m2) or obese (BMI > 30 kg/m2).7 Unintentional weight gain can occur within 3 months after completion of breast cancer treatment and is due to several contributing factors (lower metabolic rate, increased calorie consumption, and increased sedentary activity) that create a positive energy balance.8 Few cancer survivors currently meet the dietary and physical activity recommendations from the American Cancer Society; more specifically, past studies have found that only 34% of breast cancer survivors engage in the recommended level of physical activity.9,10 Weight management is a challenging task for any individual but is more so for breast cancer survivors. Breast cancer survivors are more likely to have negative body image issues but are also highly motivated to modify behaviors to adopt a healthier lifestyle.11,12 Nutrition education and weight management are not available to all cancer survivors. If they are available, they usually include simply a 30-minute consultation with a registered dietitian who reviews the basic guidelines and recommendations for cancer survivors.13,14 Therefore, most oncology follow-up visits identify that breast cancer survivorship is usually associated with notable weight gain.15-17 Commercial weight management programs have combined technology, group support, and personalized coaching to help individuals achieve healthier lifestyles. However, these programs are not geared toward cancer survivors, lack personalization for diet and exercise, and have a high attrition rate.18,19
Mobile health technology (mHealth) is rapidly gaining popularity among health care providers and consumers alike. Health care providers use mHealth to access clinical information, collaborate with care teams, communicate long distance with patients, and facilitate real-time monitoring and interventions. Patients use mHealth to track their health data, access their clinical records, and communicate with their providers.20 Among mobile technology, the most used devices are smartphones, and at least one third of smartphone owners use a health application (app). Weight management apps are the most popular types of downloaded health apps.20 These mHealth interventions are limited and do not include behavior modification techniques or accountability tactics; thus, they are ineffective, because patients typically lose interest or motivation and return to their previous behaviors and regain the weight they lost. To our knowledge, only limited tools are available that combine patient medical and wellness care and allow the clinician to personalize cancer care and intervene in real time to improve and maintain accountability.21 Currently, there is a Spanish mHealth app piloted in breast cancer survivors with a primary focus on energy balance, but its use was limited to other facets of cancer survivorship wellness.22 In addition, other mHealth apps are available for cardiovascular disease and diabetes, but these also have limitations.23,24 The aforementioned mHealth apps address some aspects of cancer survivorship care, but our goal was to create a tool that holds patients accountable for their health behaviors by intervening in real time to improve health outcomes. Therefore, we developed an mHealth tool (Methodist Hospital Cancer Health Application [MOCHA]) to improve accountability and weight control in breast cancer survivors. The purpose of this study was to test the feasibility, participant adherence, and usability of MOCHA.
PATIENTS AND METHODS
MOCHA Design and Features
MOCHA is a clinical-grade mobile application designed by a clinical care team and clinically tested/validated. MOCHA was specifically designed as a communication tool to help and empower cancer survivors through the challenging post-treatment times, to better communicate with their care providers, and to make healthy lifestyle changes and track achievements. MOCHA has many specific features that are summarized in Figure 1. The MOCHA homepage includes four main features (wellness, activity, food diary, and progress). The wellness feature has the ability to assess sleep and mood; the activity feature includes a list of both cardiovascular and strength activities with estimated calories burned, which is based on metabolic equivalent tasks.25 Patients can also authorize MOCHA to synchronize the personal data from a Fitbit account26 to automatically track activity features, such as steps, distance, calories burned, and active minutes. The food diary feature allows patients to easily log food by (1) searching a food, (2) scanning a food barcode, or (3) creating a customized food. MOCHA uses the vendor food database from Nutritionix,27 which includes more than 660,000 grocery items, more than 130,000 restaurant items, and the United States Department of Agriculture (USDA) food composition database to enable an easy log of meals and snacks. MOCHA can provide a nutritional facts summary of the food intake for both patient and care provider and can send a warning message to patients if they overtake specific nutrients, such as fat or carbohydrates. The progress feature shows a quick snapshot of the participant’s progress toward her goals. In addition, participants can access the secured-message portal to their health care teams to allow real-time communication and can monitor their laboratory test results, check their ranks among other participants, and allow physicians to set reminders for patients about their appointments or timely medication intake.
Fig 1.
Snapshots of the Methodist Hospital Cancer Health Application (MOCHA) features. Center image, home page and features wellness, food diary, activity and progress; far left images, progress of calories burned, type of exercises, mood and sleep; far right images, food intake progress, a summary of daily food diary and overall progress on diet, steps, activity, and sleep; and bottom center images, participant ranking and participant-dietitian interactions.
Architectural Design
The MOCHA system has three components: (1) smartphone tool, (2) application server, and (3) provider client (Fig 2). The smartphone tool and provider client are the applications that run on both Android and iOS operating systems. The smartphone tool as a tracking and communication tool is installed in the cell phones of participants. The provider client is installed in the cell phones of care providers to real-time monitor participant situations and communication. Both applications are Health Insurance Portability and Accountability Act compliant.28
Fig 2.
The workflow of architectural design for Methodist Hospital Cancer Health Application (MOCHA). The MOCHA data flow included an encrypted data transfer within the protected intranet of Houston Methodist Hospital and stored no sensitive data on the application server and mobile devices. MOCHA mHealth App runs on both Apple iOS and Google Android platforms. API, application program interface; IT, information technology; METEOR, Methodist Environment for Translational, Enhancement, Outcomes, and Research.
No sensitive data were stored in the mobile devices. All data, including confidential data, were sent to the application server and stored in the Methodist Environment for Translational, Enhancement, Outcomes, and Research (ie, METEOR) database. The application server is an Apache HTTP server (a free, open-source, cross-platform web server under the auspices of the Apache Software Foundation),29 which provides strong encryption using Secure Sockets Layer (SSL) protocols (a standard security protocol for establishing encrypted links between a web server and a user application in an online communication).30 The data communication among the mobile devices is secured through SSL encryption.31 The server is behind a firewall, hosted by Houston Methodist Hospital information technology department, and connected to the METEOR clinical data warehouse in Houston Methodist Hospital.32 Nutritionix27 provides the application program interface (API) to access the food database and query nutrition-related food data; MOCHA also uses a Fitbit API to synchronize participant Fitbit data. The data transfer with both API calls is unidirectional. No confidential data were sent to third-party servers.
Patient Selection
Female breast cancer survivors who were currently not on active treatment (defined as chemotherapy or radiation therapy), who were previously diagnosed with stage I, II, or III breast cancer, and who were considered overweight (BMI ≥ 25 kg/m2) were candidates for the study; endocrine therapy was allowed. In addition, the patients must have had access to a smartphone with data or internet connection, medical clearance from the oncologist, and an Eastern Cooperative Oncology Group performance status of 0 to 2. Key exclusion criteria included patients with stage IV breast cancer; male breast cancer survivors; women on active therapy within the previous 6 months; diagnoses of chronic disease/illness that precluded participation (eg, patients with diabetes who receive insulin, patients with myocardial infarction or unstable angina within the previous 6 months, or those with chronic hepatitis, rheumatoid disease, renal, or hepatic disease), neuropathy grade 2 or greater, severe osteoarthritis that limited the ability to exercise, or underweight or normal weight status (BMI < 25 kg/m2), severe depression, or pregnancy; enrollment in weight loss programs or weight loss surgery in the past 12 months; and lack smartphone or Internet connections. The study was approved by the Houston Methodist Hospital Institutional Review Board.
Patient Registration
Only the patients who consented were allowed to register for MOCHA. Thirty-three patients with cancer (survivors) were given a study Medical Record Number (MRN; not actual MRN number) and created their own usernames and passwords; the unique usernames were used to identify patients. Two patients chose to withdraw from the because of personal barriers shortly after they signed consent, and six participants did not complete the study; thus, 25 of 33 enrolled participants completed the study.
Study Design
This study was a prospective, single arm, open-label clinical trial to evaluate the feasibility and usability of MOCHA; the participants were enrolled in the oncology outpatient clinic. After they signed informed consent, the participants completed a demographic questionnaire (Data Supplement) that asked about smartphone experience, previous physical activity, and baseline risk factors. Participants reported initial body weight and received MOCHA, along with a brief orientation that discussed the key features of the tool, including nutrient intake, physical activity, and well-being.
During weeks 1 through 4, participants were encouraged to use MOCHA at least 5 days a week to monitor nutrient intake, physical activity, and well-being. Week 1 allowed the participants to adjust to use of MOCHA, and Week 4 allowed participants to complete questionnaires and report a final body weight. A registered dietitian designed personal goals for nutrient intake and physical activity for the participants. Participants were encouraged to enter their physical activities either by choosing from a menu of cardiovascular and strength training exercises or by entering their own. In addition, the participants were able to enter a food diary and monitor their progress toward their nutrition goals. Participant wellness was tracked by entering the amount of sleep as well as a daily pain and depression scale and was monitored by the clinician. The participants also could communicate with the registered dietitian through the secured message portal and receive periodic reminders. Also, participants were able to compare their uses of MOCHA with that of other participants by monitoring rankings (Fig 1).
At week 4, participants provided a final self-reported weight and completed both the system usability scale questionnaire and a post-MOCHA questionnaire that assessed three important aspects of MOCHA: navigation, accuracy, and motivation to use MOCHA. The system usability scale is a simple, 10-item scale that gives a global view of subjective assessments of usability (Data Supplement); scores greater than 72.5 are considered acceptable.33
Statistics
The sample size of the feasibility study was determined to be 33 participants. With 33 participants, we had 80% power to show that the adherence rate was significantly higher than 60% using a one-sided test for a population proportion at the .05 significance level if the true adherence rate was 80%.
RESULTS
Patient Characteristics
Thirty-three patients with early-stage breast cancer were enrolled. The average age of the cohort was 57 years (range, 35-78 years; Table 1). After the consent was signed, two participants chose to drop out of the study because of personal barriers. Twenty-five participants completed the MOCHA study; we defined completion as provision of a final weight and completion of poststudy questionnaires. All patients completed the prestudy questionnaire. The average BMI was 31.6 kg/m2, which is classified as obese; the lowest was 25.2 kg/m2 (overweight), and the highest was 53 kg/m2 (morbidly obese). Most of our participants had a comorbid condition; obesity was the most prominent at 61.3%, followed by hypertension at 45.2%, hyperlipidemia at 29%, and diabetes at 16%.Approximately half of the participants (51.6%) were on antiestrogen therapy.
Table 1.
Patient Demographic and Clinical Characteristics
Prestudy Questionnaire
Table 2 lists the findings from the prestudy questionnaire (n = 33). Consistent with our previous finding that most participants were obese, 35.5% stated that they spend more than 8 hours sitting during the day, which may be related to the high percentage of participants (67.7%) who stated that they exercise only intermittently. The results suggest that the participants are comfortable using mHealth apps: 64.6% reported more than 10 downloaded apps, and approximately the same number (64.5%) have used an mHealth app before. When asked why they quit using the mHealth app, 60% stated that they lost interest, 35% forgot to use the app, and 25% stopped because they did not lose weight.
Table 2.
Prestudy Questionnaire
Study End Points and Correlation of Weight Change With Average Daily Use of MOCHA
Most participants found MOCHA easy to use and navigate (Table 3). The median usability score was 82.5 (95% CI, 67.5 to 90.0), which is considereda better-than-acceptable score. In addition, the primary end point was adherence. The patients (n = 25) were deemed adherent if at least 75% of the enrolled participants used MOCHA at least once a week during weeks 2 and 3. The results showed that 80% of patients (20 of 25 patients) met these criteria and that the average number of daily uses was 3.5 times. Use meant that the participant must enter an item in one of MOCHA’s features (wellness, activity, or food diary).
Table 3.
Study End Points
The exploratory end points focused on weight loss and dietitian-participant interaction. The average weight loss of 2 lbs (range of weight change,+4 lbs to −10.6 lbs.) was seen among all participants, and 56% of enrolled participants lost an average of 3.5 lbs in this short 4-week study (Table 3; n = 25 participants with data). This is noteworthy, because we would expect a majority of this group to gain weight. We also found that the average (standard deviation) total number of interactions between the dietitian and the participant was 28.1 ± 19.6 (range, 9 to 115). Divided over the length of the study, this averages to at least one interaction daily between the dietitian and the participant. When we investigated the nature of the interactions more closely, we found that approximately one third of the interactions were from the participant and two thirds were from the dietitian. Figure 3A shows examples of real-time motivational interactions between the dietitian and the participant. Results shown in Figure 3B suggest a correlation (coefficient, 0.39) between utilization of MOCHA and weight loss in the 25 participants with completed data.
Fig 3.
(A) Participant and dietitian motivational interactions: examples of interactions between participant and dietitian and how motivational messages encouraged engagement with Methodist Hospital Cancer Health Application (MOCHA) from four different participants. (B) Correlation of weight change (in pounds) and average daily use of MOCHA: displays the average daily use and weight loss of each participant who completed the study (n = 25). Six participants did not complete the MOCHA study, because they did not report final weights and complete the poststudy questionnaire.
Poststudy Questionnaire
After completion of the 4-week pilot study, participants were asked to complete a poststudy questionnaire. Results showed that more than 90% of participants found MOCHA easy to use, and 72% stated that MOCHA accurately tracked their nutrition intake. Eighty-four percent of the 25 participants stated that they were motivated to use MOCHA daily and preferred it compared with other mHealth apps (ie, Fitbit and MyFitnessPal).
DISCUSSION
Treating obesity in breast cancer survivors requires novel interventions; the standard of care for breast cancer survivorship does not thoroughly address this issue. This study suggests that, through personalization and improved accountability, breast cancer survivors can lose weight and potentially maintain that weight loss by adopting healthier lifestyles. The participants reported that they were motivated to use MOCHA and preferred it to other mHealth tools. We believe that the preference is due to the real-time communication with their health care teams, specifically the dietitian. The dietitian could monitor each participant’s utilization of MOCHA and, if it stalled, could intervene and help her stay motivated to her goals. This attribute contrasts with typical 6-month clinic visit schedule, during which participants can lose motivation and experience weight gain. By monitoring the participant’s goal adherence at least weekly, the dietitian was able to effectively motivate the participant. In the absence of MOCHA, a cancer dietitian can spend an average of 30 to 45 minutes on an initial nutrition assessment and on follow-up visits in patients who have been identified in the physician’s clinic or the infusion center. This limits the opportunity for patient education and for frequent reinforcement of the goals. With MOCHA, a dietitian can review multiple patients at once, identify patients who need reinforcement, and communicate with a large number of patients via messaging in the same amount of time that it takes to see one or two patients in person.
MOCHA is a clinical-grade smartphone tool that can act as a novel weight management intervention by implementing tools to modify health behaviors to improve daily accounting of physical activity and food intake of breast cancer survivors and to improve engagement with health practitioners and peers (if desired). MOCHA provides a multilevel approach and intervention with patient education, patient engagement with peer to peer support, and supervision that provides accountability. This is a scalable feature, in which one dietitian at a cancer center is able to supervise a large number of patients with increased efficiency and productivity. This study demonstrates that MOCHA is usable and that patients were compliant with the application during the 4 weeks of the clinical trial period. A limitation of this study was that it was a short, 4-week intervention with a primary goal of determining adherence and usability of MOCHA. The reported weight loss was unexpected, and most health behavior–modification studies are designed for at least 12 weeks; therefore, our next study will be a larger study with 12 weeks of intervention and 1 year of follow-up. Future study design will include daily motivational cues to help keep the participants engaged and to serve as an educational tool to provide healthy lifestyle tips.
In conclusion, this study emphasizes the importance of using scalable and secured mobile health technology to improve patient goal adherence by providing real-time feedback and accountability with a health care team. We have shown that incorporation of the cancer care workflow into MOCHA provides timely engagement of the health care team, enables patient self-reinforcement through daily accounting of activities and nutrition intakes, and encourages feedback from peers. The clinically graded MOCHA differs from most mHealth apps currently available in the market and is dedicated to provision of continued care to patients with cancer and survivors. This study demonstrated that MOCHA has the potential to improve accountability for breast cancer survivors and help them reach their personalized goals. In addition, its modular design allows the addition of new functionality and capability with time. Ongoing work focuses on long-term behavior modification to reduce the comorbidities common in breast cancer survivors and improve the quality of cancer care for this growing population which is growing in large part because of the aging of the baby boomer generation and the silver tsunami that faces the US health care system. Thus, this work addresses an area of critical need in cancer survivorship science.34
Supported in part by the John S. Dunn Research Foundation.
Presented in part at the 39th Annual San Antonio Breast Cancer Symposium, San Antonio, TX, December 6-10, 2016, and at the 40th Annual San Antonio Breast Cancer Symposium, San Antonio, TX, December 5-9, 2017.
R.S., T.H., and X.Y. contributed equally to this work as first authors.
AUTHOR CONTRIBUTIONS
Conception and design: Renee Stubbins, Tiancheng He, Xiaohui Yu, Mamta Puppala, Chika F. Ezeana, Shenyi Chen, Joe Ensor, Polly Niravath, Jenny Chang, Stephen T.C. Wong, Tejal Patel
Administrative support: Renee Stubbins, Stephen T.C. Wong, Tejal Patel
Financial support: Stephen T.C. Wong
Provision of study material or patients: Renee Stubbins, Angel Rodriguez, Polly Niravath, Stephen T.C. Wong, Tejal Patel
Collection and assembly of data: Renee Stubbins, Tiancheng He, Xiaohui Yu, Mamta Puppala, Chika F. Ezeana, Shenyi Chen, Miguel Valdivia y Alvarado, Angel Rodriguez, Polly Niravath, Jenny Chang, Stephen T.C. Wong, Tejal Patel
Data analysis and interpretation: Renee Stubbins, Tiancheng He, Mamta Puppala, Chika F. Ezeana, Shenyi Chen, Joe Ensor, Stephen T.C. Wong, Tejal Patel
Manuscript writing: All authors
Final approval of manuscript: All authors
Accountable for all aspects of the work: All authors
AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST
The following represents disclosure information provided by authors of this manuscript. All relationships are considered compensated. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/jco/site/ifc.
Renee Stubbins
No relationship to disclose
Tiancheng He
No relationship to disclose
Xiaohui Yu
No relationship to disclose
Mamta Puppala
No relationship to disclose
Chika F. Ezeana
No relationship to disclose
Shenyi Chen
No relationship to disclose
Miguel Valdivia y Alvarado
No relationship to disclose
Joe Ensor
No relationship to disclose
Angel Rodriguez
No relationship to disclose
Polly Niravath
No relationship to disclose
Jenny Chang
No relationship to disclose
Stephen T.C. Wong
No relationship to disclose
Tejal Patel
No relationship to disclose
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