|
Advertisement |
|
|
||
 |
|
|||||
|
|||||
|
 |
||||||
|
||||||
|
||||||
|
Originally published as JCO Early Release 10.1200/JCO.2007.13.1052 on September 4 2007 © 2007 American Society of Clinical Oncology.
Move Onward, Press Forward, and Take a Deep Breath: Can Lifestyle Interventions Improve the Quality of Life of Women With Breast Cancer, and How Can We Be Sure?
School of Nursing and Department of Surgery, Duke University Medical Center, Durham, NC "The quality of life is more important than life itself." Few would argue with this statement. But the originating source might surprise you. Was it a renowned psychologist, a famous painter, or perhaps an unrivaled hedonist? No, these words were first uttered by Alexis Carrell, a French surgeon and 1912 Nobel Prize laureate recognized for his work on vascular suture and organ transplantation. In this issue, two articles report the results of randomized trials that targeted quality of life (QOL) as their primary outcome.1,2 Although both studies tested lifestyle interventions among women with breast cancer and share several similarities, they are distinctly different. The article by Courneya et al1 reports the results of a trial (n = 242) that compared aerobic or resistance exercise with usual care. Although this group of investigators is renowned for delivering exercise interventions that are well received and that improve QOL, the results of this trial are somewhat different from other reports from this group. Although secondary end points such as self-esteem were significantly improved in both intervention arms and other arm-specific differences were observed (such as increased aerobic fitness in the aerobic arm and increased muscular strength, lean body mass, and chemotherapy completion rates in the resistance exercise arm), fatigue, depression, anxiety, and, most importantly, QOL did not differ among women assigned to the exercise interventions compared with women assigned to usual care. These findings are distinctly different from those that Courneya et al3 reported in the Journal of Clinical Oncology in 2003. The results of this smaller (n = 52), two-armed trial found a significant increase in QOL with an aerobic exercise intervention compared with usual care, with change scores of +9.1 ± 14.1 v +0.3 ± 8.5 points, respectively (P < .001). So why are these findings so discrepant? Was it the intervention? Not likely, since both interventions used graduated thrice weekly aerobic regimens.1,3 Was it the outcome measure? This is a possibility because there are differences between the Functional Assessment of Cancer Therapy–Breast and Functional Assessment of Cancer Therapy–Anemia scales4,5; however, this still is unlikely. Instead, the most likely difference was that participants in the current study were actively receiving chemotherapy, whereas patients in the previous study had completed their primary treatment. Having conducted studies among patients who are in active treatment compared with patients who have completed therapy, it is easy to recognize and fully appreciate the data offered by these two trials, including adherence and attrition rates of 98.5% and 1.9%, respectively, for the former trial and 68% to 72% and 7.9%, respectively, in the most recent study. These rates are still admirable, but they point to the challenges in developing effective interventions that must overcome the host of barriers in patients who are receiving active treatment. Behavioral interventions that are instituted in these patients come during a period when patients are saddled with competing time constraints and also when their emotional and physical energies are being drained. However, such interventions also may demonstrate their greatest impact during this time of treatment. Although QOL may not necessarily be an outcome that is responsive during this point in time, other end points, such as those observed by Courneya et al (ie, improved strength, fitness, lean body mass, and chemotherapy completion rates), are certainly important outcomes. The trial conducted by Moadel et al2 is helpful in discerning the time period when behavioral interventions might be most effective in improving QOL. This study is distinctly different from that of Courneya et al1 in that it tested the efficacy of yoga, a mindfulness-based intervention, compared with an exercise intervention for improving QOL among breast cancer survivors. The sample accrued for this study (n = 128) was diverse in terms of ethnic and racial minorities (42% African American, 23% Hispanic, 23% non-Hispanic white, and 4% other) and educational level (76% high school or less and 24% with at least some college). This is an admirable achievement because two thirds of lifestyle interventions conducted to date have relied on samples that are at least 90% white and 80% college educated.6 The study is also unique with respect to treatment completion, with roughly half of the sample in active treatment and the other half having completed their therapy. Like the findings of Courneya et al,1 no significant differences in QOL, fatigue, or distress were observed between women randomly assigned to yoga and women assigned to usual care, although a significant difference was found for social well-being, with the yoga arm experiencing significantly lesser decreases than women in usual care (change scores were –0.51 v –2.78, respectively; P < .0001). However, within the subset of women (n = 71) who were not currently receiving chemotherapy, secondary analyses showed several differences between study arms, with the intervention group experiencing significantly improved QOL (P < .008), emotional well-being (P < .015), social well-being (P < .004), and spiritual well-being (P < .009) and less distress (P < .031). These results suggest that the timing of lifestyle interventions may be key if QOL is the primary outcome. Certainly, if lessons are to be learned across lifestyle interventions, it is worthwhile to consider the recent systematic review and meta-analysis by Schmitz et al7 who weighed the evidence on the impact of physical activity interventions on improving QOL during treatment and found it to be weak, whereas the evidence for interventions that were timed after treatment were judged as strong. In determining the strength of evidence for this review, Schmitz et al7 took into consideration not only the findings of previous research, but also the design features of each trial. As in the reviews of Knols et al8 and Bower et al,9 they acknowledged the importance of a carefully constructed attention control group to assure rigorous control for factors such as group context, instructor attention, number of contacts, and other factors. Unfortunately, most previous studies that have tested physical activity or mindfulness-based interventions have used usual care or waitlist controls and thus lack optimal rigor. Although the studies offered by Courneya et al1 and Moadel et al2 provide valuable information, they also exhibit this limitation. Thus, to move the science forward, lifestyle intervention trials must use an appropriate attention control, a need that may be even greater if QOL or other self-reported data serve as primary end points. In closing, let us revisit Alexis Carrell, the originator of the statement that "Quality of life is more important than life itself." What became of this Nobel laureate and father of transplantation? Unfortunately, after a strong start, he got on the wrong track and became a vocal proponent of eugenics and the Fascist party. He died in relative obscurity and ironically lost the QOL that he enjoyed in his younger years. Thus, he serves as a tragic, yet appropriate example on the importance of science and its interpretation in determining QOL, for this editorial on QOL that stresses the importance of science and its interpretation. AUTHOR'S DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST The author(s) indicated no potential conflicts of interest. NOTES published online ahead of print at www.jco.org on September 4, 2007. REFERENCES 1. Courneya KS, Segal RJ, Mackey JR, et al: Effects of aerobic and resistance exercise in breast cancer patients receiving adjuvant chemotherapy: A multicenter randomized controlled trial. J Clin Oncol 25:10.1200/JCO.2006.08.2024 2. Moadel AB, Shah C, Wylie-Rosett J, et al: Randomized controlled trial of yoga among a multiethnic sample of breast cancer patients: Effects on quality of life. J Clin Oncol 25:10.1200/JCO.2006.06.6027 3. Courneya KS, Mackey JR, Bell GJ, et al: Randomized control trial of exercise training in postmenopausal breast cancer survivors: Cardiopulmonary and quality of life outcomes. J Clin Oncol 21:1660-1668, 2003 4. Brady MJ, Cella DF, Mo F, et al: Reliability and validity of the Functional Assessment of Cancer Therapy–Breast quality of life instrument. J Clin Oncol 15:974-986, 1997 5. Cella D, Eton DT, Lai JS, et al: Combining anchor and distribution-based methods to derive minimal clinically important differences on the Functional Assessment of Cancer Therapy (FACT) anemia and fatigue scales. J Pain Symptom Manage 24:547-561, 2002[CrossRef][Medline] 6. Stull VB, Snyder DC, Demark-Wahnefried W: Lifestyle interventions in cancer survivors: Designing programs that meet the needs of this vulnerable and growing population. J Nutr 137:243S-248S, 2007 (suppl) 7. Schmitz KH, Holtzman J, Courneya KS, et al: Controlled physical activity trials in cancer survivors: A systematic review and meta-analysis. Cancer Epidemiol Biomarkers Prev 14:1588-1595, 2005 8. Knols R, Aaronson NK, Uebelhart D, et al: Physical exercise in cancer patients during and after medical treatment: A systematic review of randomized and controlled clinical trials. J Clin Oncol 23:3830-3842, 2005 9. Bower JE, Woolery A, Sternlieb B, et al: Yoga for cancer patients and survivors. Cancer Control 12:165-171, 2005[Medline] Related Articles
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
|
|||||||||||
|
|||||||||||
|
|
Copyright © 2007 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
|
