Payne, J. K., Held, J., Thorpe, J., & Shaw, H. (2008). Effect of exercise on biomarkers, fatigue, sleep disturbances, and depressive symptoms in older women with breast cancer receiving hormonal therapy. Oncology Nursing Forum, 35, 635–642.

The primary aim was to determine if a home-based walking exercise program is more effective than usual care in reducing fatigue, sleep disturbances, and depressive symptoms in older women receiving hormonal treatment for breast cancer as a feasibility study.  The secondary aim was to examine the extent to which symptoms and biomarkers of cortisol, serotonin, interleukin-6 (IL-6), and bilirubin are related and change over time.

Participants were recruited from breast cancer clinics and randomized to usual care or a prescribed walking exercise program. Participants were followed over a 14-week period. At an initial clinic visit, demographic data were collected and participants completed study instruments. Study instruments were again completed two weeks later via mail, 12 weeks after baseline at a clinic visit, and at 14 weeks via mail. Cortisol, serotonin, IL-6, and bilirubin were collected at the initial clinic visit and at 3 months. Blood samples were carefully handled to ensure appropriate handling for radioimmunoassay and other laboratory testing. At visit 1 and at 12 weeks, patients were asked to wear a sleep watch actigraph for 72 continuous hours. A study coordinator or investigator explained the walking exercise intervention, which was a moderate walking activity for 20 minutes, four times a week. Participants in the exercise group were shown how to use a pedometer that was provided to them but were not required to use it. Participants were given a log to record the duration and frequency of walking activity.

• Twenty participants (100% female) were included; data analysis was completed on 18 participants.
• Mean age was 65 years (range 56–78). 
• All participants had breast cancer and were being treated with hormonal therapy with tamoxifen, anastrozole, or letrozole.
• Of the participants, 65% were married, 55% were retired, 90% were Caucasian, and 40% had education at the college level or higher.

Participants were included if they

• Were postmenopausal status
• Reported fatigue
• Had a Karnofsky score of 80 or greater.

Individuals were excluded if they had a history of neurologic deficits or mental illness in the past year or had neuromuscular deficits that would contraindicate use of a walking program.

• Setting Type1:  Single site
• Setting Type 2:  Home
• Comprehensive cancer center in southeastern United States

This was a longitudinal, repeated measures, randomized, clinical trial.

• Revised Piper Fatigue Scale (PFS)
• Pittsburgh Sleep Quality Index (PSQI)
• Center for Epidemiological Studies – Depression Scale (CES-D)
• Sleep actigraphy measurements

Levels of fatigue over time and between groups were not significantly different. PSQI scores decreased significantly over time in the exercise group (p = 0.007) and did not change in the usual care controls. Actigraphy analysis after 12 weeks showed a shorter wake time (p = 0.02), sleep time (p = 0.05), and less movement during sleep (p = 0.002) in the exercise group. There was no difference between groups in sleep efficiency, the ratio of total sleep time while in bed. There were no differences in cortisol levels over time or between groups. ANOVA showed a significant difference between groups and across time in serotonin levels, with an intervention effect of exercise (p = 0.009). Serotonin levels were correlated with actual wake time, but correlations were not statistically significant. There were no significant differences in IL-6 or bilirubin between groups or over time. Bilirubin levels in both groups were at or above the upper limit of normal range. Correlation analysis for cortisol, IL-6, and bilirubin were not reported. There were no differences between groups or over time in depressive symptoms. Actual patient adherence to prescribed exercise was not reported. Authors reported that the walking exercise intervention was accepted in this population.

Home-based walking intervention appears to be feasible and acceptable to older women receiving hormonal therapy for breast cancer. The decline in PSQI scores in the exercise group suggests that this type of intervention may be helpful in improving sleep quality in this population. Effects of the exercise intervention on biomarkers are unclear. There was no observed effect of the exercise intervention on fatigue.

• The study had a small sample size, with less than 30 participants.
• There was no intention-to-treat analysis.
• Although significance values were reported, there were no other statistical results provided for significant findings that enabled evaluation of the strength of relationships.
• Actual adherence to the exercise program was not reported, so the actual use of exercise as prescribed cannot be determined.
• It is also unknown whether the control group performed any exercise on their own.
• Although patient self-report of exercise is a limitation itself, results of patient self-reports were not provided or discussed.
• The study design lacked an appropriate attentional control group.

A walking exercise program may be helpful to patients receiving hormonal treatment for breast cancer, but actual effects on fatigue, sleep, and depressive symptoms are unclear.