Background
Multiple myeloma (MM) is an incurable malignancy of plasma cells. In 2010 in Australia, it was estimated that 1,400 people were diagnosed with MM, representing 1.2% of all cancer diagnoses. MM is more common in men than women; the average age at diagnosis is 70 years [
1]. Although there is currently no cure for MM, modern therapy can control the disease for prolonged periods and the 5-year survival rates for MM have increased from 26% to 42% from 1985–1989 to 2005–2009 in Victoria, Australia [
2].
The preferred therapy for patients with MM depends on their age, functional status and comorbidities. In Australia, guidelines recommend that autologous stem cell transplantation (ASCT) should be the standard of care in patients up to 65–70 years following induction therapy. This therapy comprises an induction regimen incorporating novel agents (thalidomide, bortezomibor or lenalidomide) designed to preserve the capacity to harvest haematopoietic stem cells. Patients older than 65 years with poor performance status, or younger patients with comorbidities are not eligible for ASCT due to increasing toxicity, regimens usually combine melphalan and steroids with novel agents. Supportive therapy may include the use of bisphosphonates and erythropoietin as per updated guidelines [
3].
The treatment regimens for MM are complex and demanding [
3]. The impact of the underlying disease and the side effects of treatment include chronic pain, fatigue, nausea and vomiting, recurrent infections and anaemia [
4,
5]. Patients also frequently suffer from osteoporosis and osteolytic bone lesions, putting them at increased risk of pathological fracture [
6,
7]. These outcomes reduce the quality of life of patients and are often associated with increased incidence of depression, anxiety and distress [
4,
5,
8].
Physical activity has been shown, through randomised controlled trials, to improve physical and psychological outcomes among patients with solid tumours [
9‐
11]. This has led to interest in how participation in physical activity may be facilitated for cancer survivors [
12‐
14]. Physical activity behaviors, and the factors that influence these behaviors, vary by cancer diagnosis [
15‐
17], patient demographics [
6,
7,
15], and stage in the cancer journey [
15,
16]. Thus it is important to examine the barriers to physical activity and benefits of participation in physical activity for specific cancer groups, such as MM, and at a defined stage in the illness trajectory.
Examination of the specific benefits of physical activity for people with MM is a relatively new area of research, but one that is gaining increasing attention as the prevalence of MM increases and lifestyle behaviors, such as physical activity, are recognised as important factors in overall patient outcomes [
18‐
20]. Research to date, albeit limited, has shown that physical activity is safe and feasible before, during and following treatment for MM; can alleviate some of the side effects of treatment, including fatigue; and can enhance the quality of life of patients [
18,
21,
22]. Despite these promising findings, the pathophysiology of MM and associated therapies may make physical activity uptake and adherence a challenge for this group. Participation in physical activity is lower for people with MM than other cancer types [
18,
23]. In addition, Coleman et al. reported a high exercise attrition rate of 42% in MM patients who participated in a randomised trial [
22].
One way of increasing our understanding of physical activity in the lives of people with MM is to examine participation experiences and the perceived benefits of and barriers to participation. This information is essential to inform the development of evidence-based interventions to encourage physical activity uptake and adherence and to quantify the benefits of physical activity for this group. The aim of this study was to gain new insights in to the physical activity experiences, perceived benefits, and barriers to participation for patients who were treated for MM within the preceding 2–12 months. Due to limited research in this area and the exploratory nature of this study, a qualitative approach that examined physical activity experiences within the context of the patient’s broader life and from the patient’s perspective, was selected.
Methods
This study was approved by the Human Research Ethics Committee at Deakin University.
Research participants
Male and female patients who completed treatment for MM were interviewed for this study. Inclusion criteria were people living in Victoria Australia, aged 18 years and over; a diagnosis of symptomatic MM who had completed therapy (chemotherapy, radiotherapy, induction therapy and/or transplant) 2-12 months prior; and with the ability to speak English and complete English-language versions of the patient-completed measures.
Procedure
A purposive sampling technique was used to select patients who were living in Victoria, Australia. The patient database maintained by the Leukaemia Foundation of Australia was used to identify potential participants. The database was screened for patient names, cancer diagnosis, age and address details as well as approximate date(s) of treatment for MM. Potential participants were sent a cover letter and Participant Information and Consent Form, which provided an overview of the study, eligibility criteria, and an explanation of what participation in the study would involve. If patients deemed themselves eligible and wished to participate, they were asked to complete the consent form and return it. Once received, the interviewer rang the patient to confirm that they met the eligibility criteria and an interview time was arranged.
A self-administered questionnaire was mailed to participants prior to the telephone interview. Participants were asked to complete the questionnaire before completing the interview and could use it as a reference point during the interview. On completion of the interview, participants were asked to return the questionnaire using a reply paid envelope.
Telephone interviews were conducted from December 2011-February 2012. The interviews were conducted by a nurse counsellor with knowledge of MM and extensive experience in conducting interviews with cancer patients. Interviews were conducted by telephone and were recorded (with the permission of participants). Interviews continued until saturation was reached. A summary of the research findings was sent to the participants once the study was completed.
Measures
The questionnaire completed prior to the interview measured patient and clinical characteristics, including date of birth, highest level of education, postcode, living arrangements, treatment type and length of time since treatment. Current and pre diagnosis physical activity was measured using an adapted version of the Leisure Time Exercise Questionnaire developed by Godin et al. [
24,
25]. Participants recorded their average weekly physical activity prior to diagnosis (pre diagnosis physical activity) and their average weekly physical activity in the past month (current physical activity). The Leisure Time Exercise Questionnaire assesses average frequency and duration of light (e.g., easy walking), moderate (e.g., brisk walking) and strenuous (e.g., running) physical activity. It has been used in studies of cancer survivors [
26,
27] and patients with MM [
18].
A grounded theory approach was taken in this study [
28]. Interviews were semi-structured and follow up questions and probes facilitated a deeper understanding of the participants’ perceptions and experiences of physical activity. The interview prompts focused on participation in physical activity before, during and after treatment and any perceived barriers and benefits of participation. The interview was guided by a series of pre-determined prompts, with flexibility in the order in which they were covered to allow the interview to flow. Prompts included: “Can you describe your participation in exercise before during and after treatment?”; “What things stop or limit your participation in exercise?”; and “What things motivate you to exercise?”
One interviewer conducted all of the interviews. Author one briefed the interviewer about the aims and purpose of the interviews and listened to and gave feedback on interviewing style. Regular meetings were held between author one and the interviewer to discuss important themes, the point at which saturation was reached and any logistical issues.
Data analysis
Descriptive statistics were used to analyse the questionnaire data, including the demographic and clinical characteristics and participation in physical activity.
In terms of qualitative data, the interviews were transcribed verbatim and the accuracy of the transcripts was verified, with 80% checked by the researchers against the interview recordings. Data from the interviews were analysed using the nVivo software package. Pseudonyms were assigned to participants so that they could not be identified.
The analysis process was inductive and coding was used to reduce the data into meaningful themes [
29]. The coding procedures applied the “constant comparison” method [
30]. The constant comparison method utilises three stages of coding. For the initial stage, a relevant code was applied to ideas in the transcripts to develop categories which captured the meaning of the idea [
31]. Under the supervision of authors one and five, a research assistant coded the data. As a way of validating the codes, three interviews were independently coded by author one to check the interpretations of the coder and validate the themes. There was agreement between both researchers as to the dominant themes and their interpretation of the meaning from the ideas represented in the interviews.
The second stage of coding involved reducing codes through grouping similar codes into broader, more encompassing themes and comparing them to one another and cross checking back to the original interview text. In the final stage, categories were delimited to gain parsimony and focus on the aims of the study [
31]. At this stage, comparisons were made based on gender and type of therapy (ASCT or other therapies, including chemotherapy, radiotherapy). Examination of different therapy groups was important as treatment with or without ASCT may influence the functional status of the patient, which may have an impact on their physical activity. During the coding processes, the authors and interviewer met to discuss the themes that were emerging from the interviews.
In the Results section, the gender, age and main treatment type of participants are included in parentheses following direct quotes. Only the main treatment type has been included here; participants may also have been treated with a range of induction and supportive therapies including thalidomide and steroids (e.g., prednisolone and zometa).
Discussion
The purpose of this study was to explore the physical activity experiences of people with MM and perceived benefits and barriers to participation. Patients overwhelmingly reported that physical activity was beneficial; the most prominent benefits were in symptom control and recovery from the side affects of MM therapy and the psychological benefits of participation. The main barriers to physical activity related to the symptoms of MM and side effects of therapy and low self-motivation. There were some gender differences in type of physical activity that participants engaged in and benefits and barriers; and there were also some differences in benefits and barriers according to type of therapy.
Participation in physical activity decreased since prior to diagnosis, confirming the findings of previous research with MM patients [
18,
23] and other cancer survivors [
32,
33]. Physical activity was of light to moderate intensity, and walking was the most popular type of activity, followed by gardening. These findings are similar to population-based studies, which show that walking is the most popular physical activity among older adults [
34]. Walking was the most popular physical activity for both men and women, however there were some differences between men and women in physical activity participation. For example, women participated in aquatics, gym work and pilates, whereas men participated in golf, gardening and bike riding. These are consistent with gender differences in physical activity participation in the general population of adults and older adults [
34,
35].
One-quarter of participants were meeting the recommended guidelines of 150 minutes of moderate-vigorous intensity physical activity per week; this was similar to previous studies of people with multiple myeloma [
25,
36]. This compares with 30-45% of other cancer survivor groups who met the guidelines for sufficient levels of physical activity [
6,
18,
30]. Our findings reinforce that MM may be more debilitating than some other types of cancer, which represents additional challenges to performing regular physical activity for people with MM.
None of the participants from this study engaged in vigorous physical activity. We found that participating in light to moderate intensity physical activity is likely to be the most feasible for patients with MM who experience a range of physical limitations that effect mobility, and who are also at increased risk of bone fractures and infections [
6,
7]. These findings suggest that patients with MM may find it difficult to meet the American College of Sports Medicine guidelines for cancer survivors, which advise that cancer survivors avoid inactivity and follow the age-appropriate guidelines for aerobic activity; the accumulation of 150 minutes per week of moderate to vigorous intensity physical activity. However, in recognition of the specific needs of some cancer groups, the panel acknowledged that there should be some cancer site-specific alterations for patients and caution was advised for those at increased risk of fracture and infection [
37].
In this study, the social context of the physical activity was important for people with MM and social interactions were important to the overall physical activity experience; this was particularly so for women. This finding supports the findings of previous research which demonstrates that having an exercise role model or partner is positively associated with physical activity participation for patients with MM [
38], as well as other cancer groups, including prostate cancer survivors [
39] and breast cancer survivors [
40].
One of the main reported benefits of physical activity was helping to overcome the impact of MM treatment and symptoms. This might be a mechanism through which physical activity contributes to quality of life and psychological health, as previous research has demonstrated the association between symptom distress, quality of life and depression [
41].
The psychological benefits of physical activity, including cognitive, affective and coping with cancer were frequently reported by interview participants in our study. These psychological benefits are particularly important for people with MM, as depression and low quality of life are frequently reported [
4,
8]. Although no randomised controlled trials have been conducted with patients with MM, two recent meta analyses of studies of cancer survivors (primarily breast cancer) concluded that physical activity had a positive effect on psychological health [
42,
43]. However, other studies have shown no association between physical activity and depression and anxiety for breast cancer survivors [
10,
44] or colorectal cancer survivors [
45].
There is evidence that the intensity of physical activity plays an important role in outcomes [
46]. The effect of level of intensity on quality of life and psychological health outcomes is complex and there is debate about the optimal intensity, particularly for psychological health [
47]. A cross-sectional study of patients with MM by Jones et al. showed that during off treatment periods, minutes of participation in moderate plus vigorous intensity physical activity, was associated with overall quality of life and all components of quality of life except physical wellbeing, as well as reductions in fatigue and depression [
18]. Further examination of the effect of physical activity at various intensity levels on psychological health and quality of life outcomes for patients with MM is warranted.
Symptoms of MM and side effects of treatment, particularly fatigue and pain, were the predominant barriers to physical activity. Evidence suggests that symptoms of fatigue, sleep disturbances, pain and loss of appetite were significantly worse for MM patients than those with lymphoma [
48]. Fatigue and pain have been identified as barriers to physical activity in other studies of cancer survivors [
27,
49] and people with MM [
23]. Research has shown that higher levels of fatigue are associated with lower levels of physical activity for patients with MM [
18]. However, a small randomised controlled trial by Coleman et al. demonstrated that physical activity reduced fatigue for patients with MM [
21]. We found that the extent to which pain and fatigue were barriers to participation differed by treatment type, with pain experienced more by people who had been treated with therapies including chemotherapy and/or radiotherapy and fatigue experienced more by people who had a ASCT. These associations and their impact on physical activity experiences requires further investigation.
Lack of self-motivation was also a barrier in our study, particularly for men and for those who were treated with chemotherapy and/or radiotherapy. Lack of self-motivation has also been identified in other studies of cancer survivors [
49].
The strengths of this study were the inclusion of people with MM who were recently treated, which facilitated recall of physical activity prior to diagnosis and the experience of treatment. The selection of participants from a population-based database increased the possibility of gaining perspectives from people from a range of backgrounds and localities.
Limitations of the study also need to be considered when interpreting the findings. This study was cross sectional and comprised a small sample size, involving younger patients (mean age = 62 years) than the population of MM patients (mean age at diagnosis of 70 years [
1]) and findings can therefore not be generalized to the population. Participants were at least somewhat physically active; with voluntary participation, this self-selection bias is difficult to avoid. Participants had difficulty recalling their treatment regimen and we are not able to verify the accuracy of patient treatment status. The measure of pre-treatment level of physical activity was retrospective, which increases the possibility of recall error [
50]. However, the main focus of this study was on the participants’ description and lived experience of physical activity. Given these limitations, the findings of our study should be further examined through a population-based quantitative study examining the determinants of physical activity and potential outcomes such as improved quality of life (particularly levels of fatigue and pain), anxiety and depression.
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
MJC conceived of the study, participated in its design and coordination, contributed to the data analysis and interpretation and drafted the manuscript. KH contributed to the study design, development of interview questions, participant recruitment and assisted in the drafting of the manuscript, PML contributed to the study design, data analysis and interpretation and drafting of the manuscript; KSC contributed to the study design, drafting of interview prompts, interpretation and drafting of the manuscript; SJH contributed to the study design, drafting of the manuscript and provided expert advice on MM and treatments. All authors read and approved the final manuscript.