A Community Dance Intervention Engaging Breast Cancer Survivors in a Middle-income Country

"My Body, My Rhythm, My Voice": a Community Dance Intervention Engaging Breast Cancer Survivors in Physical Activity in a Middle-income Country

Stanford University, Universidad Manuela Beltrán, Pontificia Universidad Javeriana, Hospital de San Jose, University of California, Los Angeles, National Institutes of Health (NIH), National Cancer Institute (NCI)

Interventions to promote physical activity among women breast cancer survivors (BCS) in low to middle-income countries are limited. We conducted a study to assess the acceptability and preliminary effectiveness of an 8-week, 3 times/week group dance intervention for BCS delivered in Bogotá, Colombia. The effect of the intervention on participants' physical activity levels, motivation to engage in physical activity, and quality of life were evaluated, and interviews were thematically analyzed to assess program acceptability.

This is a quasi-experimental study with a control group and an intervention group. The study population are patients over 18 years of age with a diagnosis of breast cancer who have received management and are currently in remission phase (more than 1 year after finishing management with chemotherapy and radiotherapy) and who do not report having any medical contraindication for the practice of physical activity (angina, acute myocardial infarction, pulmonary embolism, arterial hypertension and uncontrolled diabetes mellitus, severe lymphedema). The control group will be patients who attend their medical check-ups at the National Cancer Institute of Colombia and the intervention group will be patients who are cared for by units of the Bogotá's medical service. It will have the written approval of the ethics committee of the respective hospitals. Being an exploratory study that investigates the acceptability and main motivations for attending physical activity sessions on a regular basis, it is considered that a sample of 30 people in the control group and 30 people in the intervention group could provide the necessary information to have in mind to develop studies with more significant sample sizes in the future. For 8 weeks the intervention group will be offered 24 classes of musicalized directed physical activity (through a training protocol adapted for patients with this underlying pathology), and 8 craft workshops, to be held in the same space as the physical activity sessions. Additionally, at the same time, healthy habits will be promoted with the control group through text messages during 8 weeks, with a two workshops (at the beginning and the end of this period). The classes and workshops will be held at the facilities of the health provider institution in a place that guarantees the privacy of the participants. For the recruitment of patients in the intervention group, women who were diagnosed with altered BI-RADS will be contacted by telephone. For the recruitment of patients from the control group, the head nurse who coordinates the follow-up program for breast cancer patients will be asked to invite the women in the study to participate. Additionally, all invited patients will receive the information through an attached information sheet. Before the start of the intervention and after it, the following measurements will be made: The questionnaires include questions about sociodemographic data, medical information, quality of life, general state of health, optimism and pessimism about life, anxiety and depression, perception of fatigue, knowledge about physical activity, self-efficacy in physical activity and social support for the practice of physical activity. These questionnaires will be administered by pollsters trained and registered through the Qualtrics application. These questionnaires will be applied by trained interviewers in a personal meeting in both health centers, in a space that ensures the confidentiality and security of the information. Objective measurements that include levels of physical activity by accelerometry and body composition by bio-impedance. These measurements will be carried out by a professional in Respiratory Therapy in the facilities of the institution that provides services where the women have been recruited, as appropriate control group or intervention group. The research team will provide the transportation service to take the participants to the facilities. To guarantee the physical safety of the people who participate, there will be a person certified in life support, who will ensure that the participant who requires entering in the most efficient way to the health system. It is worth clarifying that all study participants will have affiliation to a Health Promoting Entity through which they attend their oncology controls, and additionally, the research group will have a medical insurance policy for the patients who participate in the intervention to cover any event that may arise during it. Collection of qualitative information through focus groups led by an anthropology professional to explore what breast cancer survivors look for in a physical activity program and the main motivations and barriers to attending said program and its acceptability. In addition, information will be collected through interviews with experts who work in health promotion, disease prevention, and cancer patient management to identify those factors that are important to be able to articulate the recreation sector with the health sector in the implementation of a targeted physical activity program for breast cancer survivors. Approximately 10 to 15 interviews will be carried out according to the saturation of the information; the recruitment of these experts will be done through snowball sampling where an expert will refer to contacts related to this topic. Statistical analyzes will be carried out with SPSS and SAS, an ANOVA analysis of variance, Kruskal-Wallis and McNemar's tests of repeated measures will be carried out to establish the change in the results before and after the intervention. To support the analysis of qualitative data from both the focus groups and the interviews, the NVIVO12 software will be used. Participants will receive the aggregated results of the general study ensuring confidentiality. Additionally, the participants will receive individually the results of the anthropometric tests and stress tests so that they know their physical condition; those who find a level of risk of coronary heart disease will be explicitly suggested to consult a specialist doctor through their insurer.

Breast cancer survivors, Physical activity, Behavior change intervention, Community-based program, Mixed-methods assessment, Middle-income setting

My Body was a behavioral intervention informed by the social cognitive and self-determination theories. Based on the discussions and a systematic review of the literature, we designed the 8-week, 3 times/week rumba physical activity intervention. The goal of the intervention was to gradually increase all participants' physical activity levels to achieve significant health benefits. As part of the physical activity intervention, participants were also taught by their instructor during each class how to utilize behavioral and cognitive self-regulatory skills to increase and maintain their physical activity participation. Examples of such skills were action planning, coping planning, counter conditioning, self-evaluation, among others.

To assess the change from baseline participants' physical activity levels at 8 weeks, participants wore accelerometers for 7 consecutive days from awakening to bedtime using an elasticized belt around the waist at the right mid-axillary line. For wear-time validation, a minimum of four weekdays and a weekend day with at least 10 hours of wear during the waking time was required. Accelerometers were initialized to collect data at a sampling frequency of 80 Hz, downloaded in one-second epochs and grouped in 60-second epochs for analysis.

To assess the change from baseline participants´ motivational regulation for physical activity at 8 weeks, we used the validated Spanish version of the Behavioral Regulation in Exercise Questionnaire-3 [BREQ-3], a 23-item inventory assessing the Self-Determination Theory relevant constructs (which conceptualizes motivation as a continuum ranging from amotivation to a high level of intrinsic motivation). Responses to each item were reported on a 5-point scale ranging from 0 (not true for me) to 4 (very true for me).

To assess the change of quality of life, we used the official Colombian Spanish translation of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire. It incorporates five functioning subscales, three symptom subscales, six single symptoms, an item for illness-related financial difficulties, and a two-item general health/global QoL subscale. Each item was reported on a 4-point scale ranging from 1 (not at all) to 4 (very much), except for the general health subscale, which response options range from 1 (very poor) to 7 (excellent). High scores on the functioning subscales and the global health status/QoL subscale represent higher quality of life, while high scores on the symptom subscales indicate high levels of symptomatology. We also used a subscale of the EORTC questionnaire specific to breast cancer patients regarding physical symptoms for lymphedema; it comprises seven items with responses also ranging from 1 (not at all) to 4 (very much).

We used a semi-structured interviewing technique to ensure in-depth insights about BCS' perspectives towards physical activity, their anticipated and actual experienced barriers and facilitators to engage in the physical activity intervention, their expected and reported benefits from the physical activity intervention, and the perceived positive and negative aspects of the program.

To characterize the population, we collected surveys inquiring about sociodemographic variables (i.e., age, education, socioeconomic level, employment status, healthcare access).

Anthropometric data (height, weight) were directly measured by trained interviewers according to standardized procedures using scale and stadiometer. Body mass index (BMI) was calculated using the formula weight (kg)/height2 (m2); and classified according to the World Health Organization BMI classification

Inclusion Criteria: BCS at least six months post treatment completion More than 18 years of age Living in Bogotá Willing to attend the program and the assessments Exclusion Criteria: The presence of metastatic disease and other health conditions for which community physical activity was contraindicated

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