Effect of Physical Exercise on MRI-Assessed Brain Perfusion in Chemotherapy-Treated Breast Cancer Patients: A Randomized Controlled Trial

BACKGROUND

Exercise is a promising intervention to alleviate cognitive problems in breast cancer patients, but studies on mechanisms underlying these effects are lacking.

PURPOSE

Investigating whether an exercise intervention can affect cerebral blood flow (CBF) in cognitively impaired breast cancer patients and to determine if CBF changes relate to memory function.

STUDY TYPE

Prospective.

POPULATION

A total of 181 chemotherapy-treated stage I-III breast cancer patients with cognitive problems and relatively low physical activity levels (≤150 minutes moderate to vigorous physical activity per week), divided into an exercise (N = 91) or control group (N = 90).

FIELD STRENGTH/SEQUENCE

Two-dimensional echo planar pseudo-continuous arterial spin labeling CBF sequence at 3 T.

ASSESSMENT

The 6-month long intervention consisted of (supervised) aerobic and strength training, 4 × 1 hour/week. Measurements at baseline (2-4 years post-diagnosis) and after 6 months included gray matter CBF in the whole brain, hippocampus, anterior cingulate cortex, and posterior cingulate cortex. Physical fitness and memory function were also assessed. Subgroup analyses were performed in patients with high fatigue levels at baseline.

STATISTICAL TESTS

Multiple regression analyses with a two-sided alpha of 0.05 for all analyses.

RESULTS

There was a significant improvement in physical fitness (VO2peak in mL/minute/kg) in the intervention group (N = 53) compared to controls (N = 51, β = 1.47 mL/minute/kg, 95% CI: 0.44-2.50). However, no intervention effects on CBF were found (eg, whole brain: P = 0.565). Highly fatigued patients showed larger but insignificant treatment effects on CBF (eg, whole brain: P = 0.098). Additionally, irrespective of group, a change in physical fitness was positively associated with changes in CBF (eg, whole brain: β = 0.75, 95% CI: 0.07-1.43). There was no significant relation between CBF changes and changes in memory performance.

DATA CONCLUSION

The exercise intervention did not affect CBF of cognitively affected breast cancer patients. A change in physical fitness was associated with changes in CBF, but changes in CBF were not associated with memory functioning.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 5.

Dropout from exercise trials among cancer survivors-An individual patient data meta-analysis from the POLARIS study

INTRODUCTION

The number of randomized controlled trials (RCTs) investigating the effects of exercise among cancer survivors has increased in recent years; however, participants dropping out of the trials are rarely described. The objective of the present study was to assess which combinations of participant and exercise program characteristics were associated with dropout from the exercise arms of RCTs among cancer survivors.

METHODS

This study used data collected in the Predicting OptimaL cAncer RehabIlitation and Supportive care (POLARIS) study, an international database of RCTs investigating the effects of exercise among cancer survivors. Thirty-four exercise trials, with a total of 2467 patients without metastatic disease randomized to an exercise arm were included. Harmonized studies included a pre and a posttest, and participants were classified as dropouts when missing all assessments at the post-intervention test. Subgroups were identified with a conditional inference tree.

RESULTS

Overall, 9.6% of the participants dropped out. Five subgroups were identified in the conditional inference tree based on four significant associations with dropout. Most dropout was observed for participants with BMI >28.4 kg/m2 , performing supervised resistance or unsupervised mixed exercise (19.8% dropout) or had low-medium education and performed aerobic or supervised mixed exercise (13.5%). The lowest dropout was found for participants with BMI >28.4 kg/m2 and high education performing aerobic or supervised mixed exercise (5.1%), and participants with BMI ≤28.4 kg/m2 exercising during (5.2%) or post (9.5%) treatment.

CONCLUSIONS

There are several systematic differences between cancer survivors completing and dropping out from exercise trials, possibly affecting the external validity of exercise effects.

Moderators of exercise effects on self-reported cognitive functioning in cancer survivors: an individual participant data meta-analysis

PURPOSE

This individual participant data meta-analysis (IPD-MA) assesses exercise effects on self-reported cognitive functioning (CF) and investigates whether effects differ by patient-, intervention-, and exercise-related characteristics.

METHODS

IPD from 16 exercise RCTs, including 1987 patients across multiple types of non-metastatic cancer, was pooled. A one-stage IPD-MA using linear mixed-effect models was performed to assess exercise effects on self-reported CF (z-score) and to identify whether the effect was moderated by sociodemographic, clinical, intervention- and exercise-related characteristics, or fatigue, depression, anxiety, and self-reported CF levels at start of the intervention (i.e., baseline). Models were adjusted for baseline CF and included a random intercept at study level to account for clustering of patients within studies. A sensitivity analysis was performed in patients who reported cognitive problems at baseline.

RESULTS

Minimal significant beneficial exercise effects on self-reported CF (β=-0.09 [-0.16; -0.02]) were observed, with slightly larger effects when the intervention was delivered post-treatment (n=745, β=-0.13 [-0.24; -0.02]), and no significant effect during cancer treatment (n=1,162, β=-0.08 [-0.18; 0.02]). Larger effects were observed in interventions of 12 weeks or shorter (β=-0.14 [-0.25; -0.04]) or 24 weeks or longer (β=-0.18 [-0.32; -0.02]), whereas no effects were observed in interventions of 12-24 weeks (β=0.01 [-0.13; 0.15]). Exercise interventions were most beneficial when provided to patients without anxiety symptoms (β=-0.10 [-0.19; -0.02]) or after completion of treatment in patients with cognitive problems (β=-0.19 [-0.31; -0.06]). No other significant moderators were identified.

CONCLUSIONS

This cross-cancer IPD meta-analysis observed small beneficial exercise effects on self-reported CF when the intervention was delivered post-treatment, especially in patients who reported cognitive problems at baseline.

IMPLICATIONS FOR CANCER SURVIVORS

This study provides some evidence to support the prescription of exercise to improve cognitive functioning. Sufficiently powered trials are warranted to make more definitive recommendations and include these in the exercise guidelines for cancer survivors.

Effect of physical exercise on the hippocampus and global grey matter volume in breast cancer patients: A randomized controlled trial (PAM study)

BACKGROUND

Physical exercise in cancer patients is a promising intervention to improve cognition and increase brain volume, including hippocampal volume. We investigated whether a 6-month exercise intervention primarily impacts total hippocampal volume and additionally hippocampal subfield volumes, cortical thickness and grey matter volume in previously physically inactive breast cancer patients. Furthermore, we evaluated associations with verbal memory.

METHODS

Chemotherapy-exposed breast cancer patients (stage I-III, 2-4 years post diagnosis) with cognitive problems were included and randomized in an exercise intervention (n = 70, age = 52.5 ± 9.0 years) or control group (n = 72, age = 53.2 ± 8.6 years). The intervention consisted of 2x1 hours/week of supervised aerobic and strength training and 2x1 hours/week Nordic or power walking. At baseline and at 6-month follow-up, volumetric brain measures were derived from 3D T1-weighted 3T magnetic resonance imaging scans, including hippocampal (subfield) volume (FreeSurfer), cortical thickness (CAT12), and grey matter volume (voxel-based morphometry CAT12). Physical fitness was measured with a cardiopulmonary exercise test. Memory functioning was measured with the Hopkins Verbal Learning Test-Revised (HVLT-R total recall) and Wordlist Learning of an online cognitive test battery, the Amsterdam Cognition Scan (ACS Wordlist Learning). An explorative analysis was conducted in highly fatigued patients (score of ≥ 39 on the symptom scale 'fatigue' of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire), as previous research in this dataset has shown that the intervention improved cognition only in these patients.

RESULTS

Multiple regression analyses and voxel-based morphometry revealed no significant intervention effects on brain volume, although at baseline increased physical fitness was significantly related to larger brain volume (e.g., total hippocampal volume: R = 0.32, B = 21.7 mm³, 95 % CI = 3.0 - 40.4). Subgroup analyses showed an intervention effect in highly fatigued patients. Unexpectedly, these patients had significant reductions in hippocampal volume, compared to the control group (e.g., total hippocampal volume: B = -52.3 mm³, 95 % CI = -100.3 - -4.4)), which was related to improved memory functioning (HVLT-R total recall: B = -0.022, 95 % CI = -0.039 - -0.005; ACS Wordlist Learning: B = -0.039, 95 % CI = -0.062 - -0.015).

CONCLUSIONS

No exercise intervention effects were found on hippocampal volume, hippocampal subfield volumes, cortical thickness or grey matter volume for the entire intervention group. Contrary to what we expected, in highly fatigued patients a reduction in hippocampal volume was found after the intervention, which was related to improved memory functioning. These results suggest that physical fitness may benefit cognition in specific groups and stress the importance of further research into the biological basis of this finding.

Physical Fitness and Chemotherapy Tolerance in Patients with Early-Stage Breast Cancer

Introduction

An optimal relative dose intensity (RDI) of adjuvant chemotherapy is associated with better survival in patients with breast cancer. Little is known about the role of physical fitness in attaining an adequate RDI in patients with early-stage breast cancer. We investigated the association between pretreatment physical fitness and RDI in this population.

Methods

We pooled individual patient data from two randomized exercise trials that studied exercise programs in early breast cancer: the Physical Exercise During Adjuvant Chemotherapy Effectiveness Study (n = 230) and the Physical Activity during Chemotherapy Treatment (n = 204) study. Logistic regression models were used to evaluate the association between pretreatment fitness and achieving an optimal RDI (≥85%). In addition, we added an interaction term to the model to explore the potential moderating effect of participating in an exercise program.

Results

Data were available for 419 patients (mean age at diagnosis, 50.0 ± 8.6 yr). In the total sample, lower pretreatment physical fitness was associated with significantly lower odds of achieving ≥85% RDI: age-adjusted odds ratio (OR) of 0.66 (95% confidence interval (CI), 0.46–0.94). In patients allocated to the supervised exercise intervention during chemotherapy (n = 173), the association between pretreatment physical fitness and RDI was almost completely mitigated (OR, 0.95 (95% CI, 0.54–1.56)), whereas it was more pronounced in patients who received care as usual (n = 172; OR, 0.31 (95% CI, 0.13–0.63); P_interaction = 0.022).

Conclusions

Early-stage breast cancer patients with relatively lower levels of pretreatment physical fitness have lower odds of achieving an optimal dose of chemotherapy. Given that physical fitness is modifiable and our results suggest that following a moderate-to-high intensity exercise training during chemotherapy could improve treatment completion, clinicians should not refrain from referring patients to supportive exercise programs because of low fitness.

Loss of Paid Employment up to 4 Years after Colorectal Cancer Diagnosis-A Nationwide Register-Based Study with a Population-Based Reference Group

Simple Summary

Previous research indicated that cancer survivors have a higher risk of loss of paid employment. This is unfortunate as work is important for cancer survivors because it contributes to financial independency and quality of life. Not much work has been done on patients diagnosed with colorectal cancer while it is one of the most common cancers in the working population. We compared a group of 12,007 colorectal cancer survivors up to four years after diagnosis with the general population. We found that colorectal cancer survivors had a 56% higher risk of loss of paid employment, mainly due to work disability. Within the group of colorectal cancer survivors, those being younger, having a higher cancer stage and receiving radiotherapy, had a higher risk of loss of paid employment. Colorectal cancer survivors at high risk of loss of paid employment may benefit from work support interventions as part of cancer survivorship care.

Abstract

Cancer survivors consider work as a key aspect of cancer survivorship while previous research indicated that cancer survivors have a higher risk of unemployment. The objectives were to assess: (1) whether colorectal cancer survivors less often have paid employment at diagnosis compared to a population-based reference group, (2) whether colorectal cancer survivors with paid work have a higher risk of loss of employment up to 4 years after diagnosis compared to a population-based reference group and (3) which colorectal cancer survivors are at highest risk of loss of paid employment. In a nationwide register-based study, persons diagnosed with colorectal cancer (N = 12,007) as registered in the Netherlands Cancer Registry, were compared on loss of paid employment with a sex and age-matched population-based reference group (N = 48,028) from Statistics Netherlands. Cox regression analyses were conducted. Colorectal cancer survivors had a higher risk of loss of paid employment (HR 1.56 [1.42, 1.71]). Within the group of colorectal cancer survivors, risk of loss of paid employment was lower for older survivors (>60 vs. 45–55) (HR 0.64 [0.51, 0.81]) and higher for those with a more advanced cancer stage (IV vs. I) (HR 1.89 [1.33, 2.70]) and those receiving radiotherapy (HR 1.37 [1.15, 1.63]). Colorectal cancer survivors at high risk of loss of paid employment may benefit from work support interventions as part of cancer survivorship.

Moderators of Exercise Effects on Cancer-related Fatigue: A Meta-analysis of Individual Patient Data

PURPOSE

Fatigue is a common and potentially disabling symptom in patients with cancer. It can often be effectively reduced by exercise. Yet, effects of exercise interventions might differ across subgroups. We conducted a meta-analysis using individual patient data of randomized controlled trials (RCT) to investigate moderators of exercise intervention effects on cancer-related fatigue.

METHODS

We used individual patient data from 31 exercise RCT worldwide, representing 4366 patients, of whom 3846 had complete fatigue data. We performed a one-step individual patient data meta-analysis, using linear mixed-effect models to analyze the effects of exercise interventions on fatigue (z score) and to identify demographic, clinical, intervention- and exercise-related moderators. Models were adjusted for baseline fatigue and included a random intercept on study level to account for clustering of patients within studies. We identified potential moderators by testing their interaction with group allocation, using a likelihood ratio test.

RESULTS

Exercise interventions had statistically significant beneficial effects on fatigue (β = -0.17; 95% confidence interval [CI], -0.22 to -0.12). There was no evidence of moderation by demographic or clinical characteristics. Supervised exercise interventions had significantly larger effects on fatigue than unsupervised exercise interventions (βdifference = -0.18; 95% CI -0.28 to -0.08). Supervised interventions with a duration ≤12 wk showed larger effects on fatigue (β = -0.29; 95% CI, -0.39 to -0.20) than supervised interventions with a longer duration.

CONCLUSIONS

In this individual patient data meta-analysis, we found statistically significant beneficial effects of exercise interventions on fatigue, irrespective of demographic and clinical characteristics. These findings support a role for exercise, preferably supervised exercise interventions, in clinical practice. Reasons for differential effects in duration require further exploration.

Effects and moderators of exercise on sleep in adults with cancer: Individual patient data and aggregated meta-analyses

OBJECTIVES

To evaluate the effects of exercise interventions on sleep disturbances and sleep quality in patients with mixed cancer diagnoses, and identify demographic, clinical, and intervention-related moderators of these effects.

METHODS

Individual patient data (IPD) and aggregated meta-analyses of randomized controlled trials (RCTs). Using data from the Predicting OptimaL cAncer RehabIlitation and Supportive care project, IPD of 2173 adults (mean age = 54.8) with cancer from 17 RCTs were analyzed. A complementary systematic search was conducted (until November 2018) to study the overall effects and test the representativeness of analyzed IPD. Effect sizes of exercise effects on self-reported sleep outcomes were calculated for all included RCTs. Linear mixed-effect models were used to evaluate the effects of exercise on post-intervention outcome values, adjusting for baseline values. Moderator effects were studied by testing interactions for demographic, clinical and intervention-related characteristics.

RESULTS

For all 27 eligible RCTs from the updated search, exercise interventions significantly decreased sleep disturbances in adults with cancer (g = -0.09, 95% CI [-0.16; -0.02]). No significant effect was obtained for sleep quality. RCTs included in IPD analyses constituted a representative sample of the published literature. The intervention effects on sleep disturbances were not significantly moderated by any demographic, clinical, or intervention-related factor, nor by sleep disturbances.

CONCLUSIONS

This meta-analysis provides some evidence that, compared to control conditions, exercise interventions may improve sleep disturbances, but not sleep quality, in cancer patients, although this effect is of a small magnitude. Among the investigated variables, none was found to significantly moderate the effect of exercise interventions on sleep disturbances.

Effect of physical exercise on cognitive function and brain measures after chemotherapy in patients with breast cancer (PAM study): protocol of a randomised controlled trial

INTRODUCTION

After treatment with chemotherapy, many patients with breast cancer experience cognitive problems. While limited interventions are available to improve cognitive functioning, physical exercise showed positive effects in healthy older adults and people with mild cognitive impairment. The Physical Activity and Memory study aims to investigate the effect of physical exercise on cognitive functioning and brain measures in chemotherapy-exposed patients with breast cancer with cognitive problems.

METHODS AND ANALYTICS

One hundred and eighty patients with breast cancer with cognitive problems 2-4 years after diagnosis are randomised (1:1) into an exercise intervention or a control group. The 6-month exercise intervention consists of twice a week 1-hour aerobic and strength exercises supervised by a physiotherapist and twice a week 1-hour Nordic or power walking. The control group is asked to maintain their habitual activity pattern during 6 months. The primary outcome (verbal learning) is measured at baseline and 6 months. Further measurements include online neuropsychological tests, self-reported cognitive complaints, a 3-tesla brain MRI, patient-reported outcomes (quality of life, fatigue, depression, anxiety, work performance), blood sampling and physical fitness. The MRI scans and blood sampling will be used to gain insight into underlying mechanisms. At 18 months online neuropsychological tests, self-reported cognitive complaints and patient-reported outcomes will be repeated.

ETHICS AND DISSEMINATION

Study results may impact usual care if physical exercise improves cognitive functioning for breast cancer survivors.

TRIAL REGISTRATION NUMBER

NTR6104.

Attendance and compliance with an exercise program during localized breast cancer treatment in a randomized controlled trial: The PACT study

PURPOSE

Maintaining high adherence rates (session attendance and compliance) in exercise programs during breast cancer treatment can be challenging. We aimed to identify adherence rates and predictors to an exercise program during adjuvant breast cancer treatment.

METHODS

Ninety-two patients with localized breast cancer undergoing chemotherapy were randomly assigned to an 18-week supervised moderate-to-high intensity aerobic and resistance exercise program, including two 1-hour sessions/week. Additionally, participants were asked to be physically active for at least 30 minutes/day on at least three other days. We report median percentages for attendance, compliance with the prescribed duration and intensity of aerobic and muscle strength exercises, and the exercise advice given. Predictors included in univariate and multivariable linear regression models were demographical, tumor- and treatment-related factors, constructs of the theory of planned behavior, psychological and physical factors.

RESULTS

Patients attended 83% (interquartile range: 69-91%) of the supervised sessions. Compliance with the duration of aerobic exercise, high-intensity aerobic exercise (cycling at the ventilatory threshold), muscle strength exercises and the exercise advice were 88%(64-97%), 50%(22-82%), 84%(65-94%) and 61%(33%-79%), respectively. Education, radiotherapy, BMI and physical fatigue were important predictors of adherence to supervised exercise. Beliefs about planned behaviors were important predictors, especially for compliance with the exercise advice.

CONCLUSIONS

Attendance to and compliance with an 18-week aerobic and strength exercise program were high. The lowest compliance was found for high-intensity supervised aerobic exercise. The identified predictors should be considered when designing or adapting exercise programs for patients with localized breast cancer to increase adherence.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN43801571 Dutch Trial Register NTR2138.

Targeting Exercise Interventions to Patients With Cancer in Need: An Individual Patient Data Meta-Analysis

Background

Exercise effects in cancer patients often appear modest, possibly because interventions rarely target patients most in need. This study investigated the moderator effects of baseline values on the exercise outcomes of fatigue, aerobic fitness, muscle strength, quality of life (QoL), and self-reported physical function (PF) in cancer patients during and post-treatment.

Methods

Individual patient data from 34 randomized exercise trials (n = 4519) were pooled. Linear mixed-effect models were used to study moderator effects of baseline values on exercise intervention outcomes and to determine whether these moderator effects differed by intervention timing (during vs post-treatment). All statistical tests were two-sided.

Results

Moderator effects of baseline fatigue and PF were consistent across intervention timing, with greater effects in patients with worse fatigue (Pinteraction = .05) and worse PF (Pinteraction = .003). Moderator effects of baseline aerobic fitness, muscle strength, and QoL differed by intervention timing. During treatment, effects on aerobic fitness were greater for patients with better baseline aerobic fitness (Pinteraction = .002). Post-treatment, effects on upper (Pinteraction < .001) and lower (Pinteraction = .01) body muscle strength and QoL (Pinteraction < .001) were greater in patients with worse baseline values.

Conclusion

Although exercise should be encouraged for most cancer patients during and post-treatments, targeting specific subgroups may be especially beneficial and cost effective. For fatigue and PF, interventions during and post-treatment should target patients with high fatigue and low PF. During treatment, patients experience benefit for muscle strength and QoL regardless of baseline values; however, only patients with low baseline values benefit post-treatment. For aerobic fitness, patients with low baseline values do not appear to benefit from exercise during treatment.

Effects and moderators of exercise on muscle strength, muscle function and aerobic fitness in patients with cancer: a meta-analysis of individual patient data

Objective

To optimally target exercise interventions for patients with cancer, it is important to identify which patients benefit from which interventions.

Design

We conducted an individual patient data meta-analysis to investigate demographic, clinical, intervention-related and exercise-related moderators of exercise intervention effects on physical fitness in patients with cancer.

Data sources

We identified relevant studies via systematic searches in electronic databases (PubMed, Embase, PsycINFO and CINAHL).

Eligibility criteria

We analysed data from 28 randomised controlled trials investigating the effects of exercise on upper body muscle strength (UBMS) and lower body muscle strength (LBMS), lower body muscle function (LBMF) and aerobic fitness in adult patients with cancer.

Results

Exercise significantly improved UBMS (β=0.20, 95% Confidence Interval (CI) 0.14 to 0.26), LBMS (β=0.29, 95% CI 0.23 to 0.35), LBMF (β=0.16, 95% CI 0.08 to 0.24) and aerobic fitness (β=0.28, 95% CI 0.23 to 0.34), with larger effects for supervised interventions. Exercise effects on UBMS were larger during treatment, when supervised interventions included ≥3 sessions per week, when resistance exercises were included and when session duration was >60 min. Exercise effects on LBMS were larger for patients who were living alone, for supervised interventions including resistance exercise and when session duration was >60 min. Exercise effects on aerobic fitness were larger for younger patients and when supervised interventions included aerobic exercise.

Conclusion

Exercise interventions during and following cancer treatment had small effects on UBMS, LBMS, LBMF and aerobic fitness. Demographic, intervention-related and exercise-related characteristics including age, marital status, intervention timing, delivery mode and frequency and type and time of exercise sessions moderated the exercise effect on UBMS, LBMS and aerobic fitness.

Four-year effects of exercise on fatigue and physical activity in patients with cancer

BACKGROUND

In the earlier randomized controlled Physical Activity during Cancer Treatment (PACT) study, we found beneficial effects of an 18-week supervised exercise program on fatigue in patients with newly diagnosed breast or colon cancer undergoing adjuvant treatment. The present study assessed long-term effects of the exercise program on levels of fatigue and physical activity 4 years after participation in the PACT study.

METHODS

The original study was a two-armed, multicenter randomized controlled trial comparing an 18-week supervised exercise program to usual care among 204 breast cancer patients and 33 colon cancer patients undergoing adjuvant treatment. Of the 237 PACT participants, 197 participants were eligible and approached to participate in the 4-year post-baseline measurements, and 128 patients responded. We assessed fatigue and physical activity levels at 4 years post-baseline and compared this to levels at baseline, post-intervention (18 weeks post-baseline), and at 36 weeks post-baseline.

RESULTS

Intention-to-treat mixed linear effects model analyses showed that cancer patients in the intervention group reported significantly higher moderate-to-vigorous total physical activity levels (141.46 min/week (95% confidence interval (CI) 1.31, 281.61, effect size (ES) = 0.22) after 4 years compared to the usual care group. Furthermore, cancer patients in the intervention group tended to experience less physical fatigue at 4 years post-baseline compared to the usual care group (- 1.13, 95% CI -2.45, 0.20, ES = 0.22), although the result was not statistically significant.

CONCLUSION

Patients with breast or colon cancer who participated in the 18-week exercise intervention showed significant higher levels of moderate-to-vigorous total physical activity levels and a tendency towards lower physical fatigue levels 4 years post-baseline. Our result indicate that exercising during chemotherapy is a promising strategy for minimizing treatment-related side effects, both short and long term.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN43801571 , Dutch Trial Register NTR2138 . Trial registered on 9 December 2009.

Abstract P6-12-06: Effect and moderators of exercise on fatigue in patients with breast cancer: Meta-analysis of individual patient data

Background - Fatigue is one of the most common and disabling complaints in patients with breast cancer and can effectively be reduced by physical exercise, with small to moderate effect sizes. To identify heterogeneity in responses to exercise and to further personalize exercise prescriptions, moderators of exercise effects on fatigue should be investigated. However, most randomized controlled trials (RCTs) are not adequately powered for such analyses. Therefore we conducted meta-analyses using the individual patient data of several exercise RCTs. The aim is to investigate the effect and moderators of physical exercise on cancer-related fatigue in patients with breast cancer.

Methods - Within the Predicting OptimaL cAncer RehabIlitation and Supportive care (POLARIS) consortium, principal investigators of 34 exercise RCTs worldwide have shared their individual patient data. Twenty-two of these RCTs included patients with breast cancer with a total sample size of 3,061. Different questionnaires to assess level of fatigue were used, which was acknowledged by using z-scores in the analysis. A one-step individual patient data meta-analysis, using a linear mixed-effect model adjusted for baseline fatigue, with a random intercept on study (to account for study clustering) was undertaken to investigate effect of exercise on fatigue. The result, a between-group difference in z-scores, corresponds to a Cohen's d effect size. An interaction term was included in the model to assess potential moderators including demographic (age, marital status, education), clinical (body mass index, presence of distant metastasis), intervention-related (intervention timing, delivery mode and duration), and exercise-related (exercise type, frequency, intensity, duration) characteristics.

Results – Exercise significantly reduced fatigue reported by women with breast cancer (β= -0.15, 95% CI -0.21;-0.09). This effect did not differ significantly between patients with different demographic and clinical characteristics (p-valuesinteraction &gt;0.05). Also, neither timing (during or post-treatment) and duration of the intervention, nor exercise-related factors moderated intervention effects on fatigue. Supervised exercise had significantly larger effects on fatigue than unsupervised exercise (βdifference= -0.17, 95%CI -0.28;-0.05). Compared to the control group, supervised exercise significantly improved fatigue (β = -0.21, 95%CI = -0.28;-0.14), while unsupervised exercise did not (β = -0.04, 95%CI = -0.14;0.06).

Conclusion – Exercise significantly reduces fatigue in patients with breast cancer across subgroups formed on the basis of age, marital status, education level, body mass index, and presence of distant metastasis. The effect of exercise is significantly larger when performed under supervision. Hence, exercise, and preferably supervised exercise, represents a viable intervention for the prevention and treatment of fatigue among patients with breast cancer.

Citation Format: van Vulpen JK, Sweegers MG, Kalter J, Peeters PH, Courneya KS, Newton RU, Aaronson NK, Jacobsen PB, Steindorf K, Stuiver MM, Hayes S, Mesters I, Knoop H, Goedendorp M, Mutrie N, Thorsen L, Schmidt M, Sonke GS, Bohus M, James EL, Oldenburg HS, Velthuis MJ, Nollet F, Wenzel J, Wiskemann J, Galvão DA, Chinapaw MJ, Irwin ML, Griffith KA, van Weert E, Daley AJ, McConnachie A, Schulz K-H, Short CE, Plotnikoff RC, Potthoff K, van Beurden M, van Harten WH, Schmitz KH, Winters-Stone KM, Taaffe DR, van Mechelen W, Kersten M-J, Verdonck-de Leeuw IM, Brug J, Buffart LM, May AM. Effect and moderators of exercise on fatigue in patients with breast cancer: Meta-analysis of individual patient data [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-06.

Effects of physical exercise on markers of inflammation in breast cancer patients during adjuvant chemotherapy

PURPOSE

Exercise has been shown to reduce fatigue during cancer treatment. Hypothesized mechanisms include inflammatory pathways. Therefore, we investigated effects of exercise on markers of inflammation in breast cancer patients during adjuvant chemotherapy.

METHODS

We pooled data from two randomized controlled exercise intervention trials with breast cancer patients during adjuvant chemotherapy (n = 130), which had previously shown beneficial effects of exercise on fatigue. Exercise comprised a 12-week resistance training (BEATE study) or an 18-week combined resistance and aerobic training (PACT study). Serum IL-6, IL-1ra, and the IL-6/IL-1ra ratio were quantified at baseline, mid-intervention, post-intervention, and 6-9 months post-baseline.

RESULTS

Mixed effect models showed significant increases in IL-6 and IL-6/IL-1ra ratio during chemotherapy and decreases afterwards. Differences between exercise and control group were not significant at any time point. Changes in total cancer-related fatigue were significantly correlated with changes in IL-6/IL-1ra ratio (partial correlation r = 0.23) and IL-6 (r = 0.21), and changes in physical cancer-related fatigue with changes in IL-6/IL-1ra ratio (r = 0.21).

CONCLUSIONS

Changes in fatigue were slightly correlated with changes in inflammatory markers, and there was a strong inflammatory response to adjuvant chemotherapy. The supervised exercise training did not counteract this increase in inflammation, suggesting that beneficial effects of exercise on fatigue during adjuvant chemotherapy for breast cancer are not essentially mediated by IL-6, IL-1ra, or the IL-6/IL-1ra ratio.

Cost-effectiveness analysis of an 18-week exercise programme for patients with breast and colon cancer undergoing adjuvant chemotherapy: the randomised PACT study

OBJECTIVE

Meta-analyses show that exercise interventions during cancer treatment reduce cancer-related fatigue. However, little is known about the cost-effectiveness of such interventions. Here we aim to assess the cost-effectiveness of the 18-week physical activity during cancer treatment (PACT) intervention for patients with breast and colon cancer. The PACT trial showed beneficial effects for fatigue and physical fitness.

DESIGN

Cost-effectiveness analyses with a 9-month time horizon (18 weeks of intervention and 18 weeks of follow-up) within the randomised controlled multicentre PACT study.

SETTING

Outpatient clinics of 7 hospitals in the Netherlands (1 academic and 6 general hospitals) PARTICIPANTS: 204 patients with breast cancer and 33 with colon cancer undergoing adjuvant treatment including chemotherapy.

INTERVENTION

Supervised 1-hour aerobic and resistance exercise (twice per week for 18 weeks) or usual care.

MAIN OUTCOME MEASURES

Costs, quality-adjusted life years (QALY) and the incremental cost-effectiveness ratio.

RESULTS

For colon cancer, the cost-effectiveness analysis showed beneficial effects of the exercise intervention with incremental costs savings of €4321 and QALY improvements of 0.03. 100% of bootstrap simulations indicated that the intervention is dominant (ie, cheaper and more effective). For breast cancer, the results did not indicate that the exercise intervention was cost-effective. Incremental costs were €2912, and the incremental effect was 0.01 QALY. At a Dutch threshold value of €20 000 per QALY, the probability that the intervention is cost-effective was 2%.

CONCLUSIONS

Our results suggest that the 18-week exercise programme was cost-effective for colon cancer, but not for breast cancer.

TRIAL REGISTRATION NUMBER

ISRCTN43801571.

Effects of an Exercise Program in Colon Cancer Patients undergoing Chemotherapy

PURPOSE

Fatigue is a common problem among colon cancer patients and typically increases during chemotherapy. Exercise during chemotherapy might have beneficial effects on fatigue. To investigate the short- and long-term effects of an exercise program in colon cancer patients during adjuvant treatment, the Physical Activity During Cancer Treatment study was conducted.

METHODS

In this multicenter randomized controlled trial, 33 colon cancer patients undergoing chemotherapy (21 men and 12 women) were randomly assigned to either a group receiving an 18-wk supervised exercise program (n = 17) or to usual care (n = 16). The primary outcome was fatigue as measured by the Multidimensional Fatigue Inventory and the Fatigue Quality List. Secondary outcomes were quality of life, physical fitness, anxiety, depression, body weight, and chemotherapy completion rate. Outcome assessment took place at baseline, postintervention (18 wk) and at 36 wk.

RESULTS

Intention-to-treat mixed linear model analyses showed that patients in the intervention group experienced significantly less physical fatigue at 18 wk and general fatigue at 36 wk (mean between group differences, -3.2; 95% confidence interval [CI], -6.2 to -0.2; effect size [ES], -0.9 and -2.7; 95% CI, -5.2 to -0.1; ES, -0.8, respectively), and reported higher physical functioning (12.3; 95% CI, 3.3-21.4; ES, 1.0) compared with patients in the usual care group.

CONCLUSION

The Physical Activity During Cancer Treatment trial shows that an 18-wk supervised exercise program in colon cancer patients during chemotherapy is safe and feasible. The intervention significantly reduced physical fatigue at 18 wk and general fatigue at 36 wk. Considering the number of patients included in the present study, replication in a larger study population is required.

Effects of an 18-week exercise programme started early during breast cancer treatment: a randomised controlled trial

BACKGROUND

Exercise started shortly after breast cancer diagnosis might prevent or diminish fatigue complaints. The Physical Activity during Cancer Treatment (PACT) study was designed to primarily examine the effects of an 18-week exercise intervention, offered in the daily clinical practice setting and starting within 6 weeks after diagnosis, on preventing an increase in fatigue.

METHODS

This multi-centre controlled trial randomly assigned 204 breast cancer patients to usual care (n = 102) or supervised aerobic and resistance exercise (n = 102). By design, all patients received chemotherapy between baseline and 18 weeks. Fatigue (i.e., primary outcome at 18 weeks), quality of life, anxiety, depression, and physical fitness were measured at 18 and 36 weeks.

RESULTS

Intention-to-treat mixed linear model analyses showed that physical fatigue increased significantly less during cancer treatment in the intervention group compared to control (mean between-group differences at 18 weeks: -1.3; 95 % CI -2.5 to -0.1; effect size -0.30). Results for general fatigue were comparable but did not reach statistical significance (-1.0, 95%CI -2.1; 0.1; effect size -0.23). At 18 weeks, submaximal cardiorespiratory fitness and several muscle strength tests (leg extension and flexion) were significantly higher in the intervention group compared to control, whereas peak oxygen uptake did not differ between groups. At 36 weeks these differences were no longer statistically significant. Quality of life outcomes favoured the exercise group but were not significantly different between groups.

CONCLUSIONS

A supervised 18-week exercise programme offered early in routine care during adjuvant breast cancer treatment showed positive effects on physical fatigue, submaximal cardiorespiratory fitness, and muscle strength. Exercise early during treatment of breast cancer can be recommended. At 36 weeks, these effects were no longer statistically significant. This might have been caused by the control participants' high physical activity levels during follow-up.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN43801571, Dutch Trial Register NTR2138. Trial registered on December 9th, 2009.

Control group design, contamination and drop-out in exercise oncology trials: a systematic review

Purpose

Important considerations for exercise trials in cancer patients are contamination and differential drop-out among the control group members that might jeopardize the internal validity. This systematic review provides an overview of different control groups design characteristics of exercise-oncology trials and explores the association with contamination and drop-out rates.

Methods

Randomized controlled exercise-oncology trials from two Cochrane reviews were included. Additionally, a computer-aided search using Medline (Pubmed), Embase and CINAHL was conducted after completion date of the Cochrane reviews. Eligible studies were classified according to three control group design characteristics: the exercise instruction given to controls before start of the study (exercise allowed or not); and the intervention the control group was offered during (any (e.g., education sessions or telephone contacts) or none) or after (any (e.g., cross-over or exercise instruction) or none) the intervention period. Contamination (yes or no) and excess drop-out rates (i.e., drop-out rate of the control group minus the drop-out rate exercise group) were described according to the three design characteristics of the control group and according to the combinations of these three characteristics; so we additionally made subgroups based on combinations of type and timing of instructions received.

Results

40 exercise-oncology trials were included based on pre-specified eligibility criteria. The lowest contamination (7.1% of studies) and low drop-out rates (excess drop-out rate -4.7±9.2) were found in control groups offered an intervention after the intervention period. When control groups were offered an intervention both during and after the intervention period, contamination (0%) and excess drop-out rates (-10.0±12.8%) were even lower.

Conclusions

Control groups receiving an intervention during and after the study intervention period have lower contamination and drop-out rates. The present findings can be considered when designing future exercise-oncology trials.

Cardiopulmonary exercise testing in cancer rehabilitation: a systematic review

This systematic review aims to get insight into the feasibility of cardiopulmonary exercise testing (CPET) in patients with cancer prior to a physical exercise programme. We will focus on quality (defined as the adherence to international guidelines for methods of CPET) and safety of CPET. Furthermore, we compare the peak oxygen uptake (·VO(2peak)) values of patients with cancer with reference values for healthy persons to put these values into a clinical perspective. A computer aided search with 'cardiopulmonary exercise testing' and 'cancer' using MEDLINE, EMBASE, Pedro, CINAHL® and SPORTDiscus™ was carried out. We included studies in which CPET with continuous gas exchange analysis has been performed prior to a physical exercise programme in adults with cancer. Twenty studies describing 1158 patients were eligible. Reported adherence to international recommendations for CPET varied per item. In most studies, the methods of CPET were not reported in detail. Adverse events occurred in 1% of patients. The percentage ·VO(2peak) of reference values for healthy persons varied between 65% and 89% for tests before treatment, between 74% and 96% for tests during treatment and between 52% and 117% for tests after treatment. Our results suggest that CPET is feasible and seems to be safe for patients with cancer prior to a physical exercise programme. We recommend that standard reporting and quality guidelines should be followed for CPET methods. The decreased ·VO(2peak) values of patients with cancer indicate that physical exercise should be implemented in their standard care.

Role of fear of movement in cancer survivors participating in a rehabilitation program: a longitudinal cohort study

OBJECTIVE

To study the relationship between fear of movement and perceived global health status and the role of rehabilitation with graded activity in cancer survivors.

DESIGN

Longitudinal cohort study.

SETTING

Rehabilitation centers.

PARTICIPANTS

Cancer survivors (N=1236).

INTERVENTION

Twelve-week graded activity rehabilitation program.

MAIN OUTCOME MEASURES

Fear of movement (Modified Tampa Scale for Kinesiophobia-Fatigue), fatigue (Functional Assessment of Cancer Therapy-Fatigue), and perceived global health status (European Organisation Research and Treatment of Cancer Quality of Life Questionnaire C30) were measured at baseline and after rehabilitation. We performed multiple linear regression analyses to examine the association between fear of movement and perceived global health status at baseline. Differences between baseline and postintervention scores were assessed with a paired t test and effect sizes (ESs). Hierarchical multiple regression analyses were used to investigate whether changes in fear of movement were associated with perceived global health status.

RESULTS

Fear of movement was associated with perceived global health status prior to rehabilitation (P=.001). Only participants with high scores on baseline fear of movement showed a considerable decrease in fear of movement after rehabilitation (ES=-.69; 95% confidence interval [CI], -.80 to -.57); the reduction was largest for fears because of a somatic focus (ES=-.57; 95% CI, -.68 to -.45). Changes in fear of movement because of a somatic focus were related to perceived global health status postintervention (P=.001).

CONCLUSIONS

Fear of movement is associated with the perceived global health status of cancer survivors. Fear of movement decreases after rehabilitation with graded activity in high scorers on baseline fear of movement.

Alternatives for randomization in lifestyle intervention studies in cancer patients were not better than conventional randomization

OBJECTIVE

Assessing effects of lifestyle interventions in cancer patients has some specific challenges. Although randomization is urgently needed for evidence-based knowledge, sometimes it is difficult to apply conventional randomization (i.e., consent preceding randomization and intervention) in daily settings. Randomization before seeking consent was proposed by Zelen, and additional modifications were proposed since. We discuss four alternatives for conventional randomization: single and double randomized consent design, two-stage randomized consent design, and the design with consent to postponed information.

STUDY DESIGN AND SETTING

We considered these designs when designing a study to assess the impact of physical activity on cancer-related fatigue and quality of life. We tested the modified Zelen design with consent to postponed information in a pilot. The design was chosen to prevent drop out of participants in the control group because of disappointment about the allocation.

RESULTS

The result was a low overall participation rate most likely because of perceived lack of information by eligible patients and a relatively high dropout in the intervention group.

CONCLUSION

We conclude that the alternatives were not better than conventional randomization.

[Guideline "Cancer rehabilitation"]

Initiated by IKNL (Integraal Kankercentrum Nederland), a multidisciplinary guideline for cancer rehabilitation for adult oncology patients has been developed. The guideline describes the rehabilitation care of adult patients with cancer, during and after treatment. The guideline focuses on (a) prevalence of complaints either resulting from cancer or the treatment, (b) detection of these complaints and indicated referral, (c) the intake procedure before cancer rehabilitation, (d) intervention and evaluation within cancer rehabilitation and (e) the importance of patient empowerment. The guideline is directed at all professionals giving care to patients with cancer. It concerns those (such as medical specialists, general practitioners and nurses) who are responsible for detecting cancer-related complaints and for referral to cancer rehabilitation, as well as health care professionals involved in cancer rehabilitation care (such as consultants in rehabilitation medicine, physiotherapists and psychologists). The main goal of the guideline is that every cancer patient or ex-cancer patient with (residual) complaints resulting from cancer or its treatment receives timely and appropriate cancer rehabilitation.

Physical Activity during Cancer Treatment (PACT) Study: design of a randomised clinical trial

Background

Fatigue is a major problem of cancer patients. Thirty percent of cancer survivors report serious fatigue three years after finishing treatment. There is evidence that physical exercise during cancer treatment reduces fatigue. This may also lead to an improvement of quality of life. Such findings may result in a decrease of healthcare related expenditures and societal costs due to sick leave. However, no studies are known that investigated these hypotheses. Therefore, the primary aim of our study is to assess the effect of exercise during cancer treatment on reducing complaints of fatigue and on reducing health service utilisation and sick leave.

Methods/Design

The Physical Activity during Cancer Treatment study is a multicentre randomised controlled trial in 150 breast and 150 colon cancer patients undergoing cancer treatment. Participants will be randomised to an exercise or a control group. In addition to the usual care, the exercise group will participate in an 18-week supervised group exercise programme. The control group will be asked to maintain their habitual physical activity pattern. Study endpoints will be assessed after 18 weeks (short term) and after 9 months (long term). Validated questionnaires will be used. Primary outcome: fatigue (Multidimensional Fatigue Inventory and Fatigue Quality List) and cost-effectiveness, health service utilisation and sick leave. Secondary outcome: health related quality of life (European Organisation Research and Treatment of Cancer-Quality of Life questionnaire-C30, Short Form 36 healthy survey), impact on functioning and autonomy (Impact on functioning and autonomy questionnaire), anxiety and depression (Hospital Anxiety and Depression Scale), physical fitness (aerobic peak capacity, muscle strength), body composition and cognitive-behavioural aspects. To register health service utilisation and sick leave, participants will keep diaries including the EuroQuol-5D. Physical activity level will be measured using the Short Questionnaire to Assess Health-Enhancing Physical Activity and will be monitored with an exercise log and a pedometer.

Discussion

This study investigates the (cost)-effectiveness of exercise during adjuvant treatment of patients with breast or colon cancer. If early physical exercise proves to be (cost) effective, establishing standardised physical exercise programmes during cancer treatment will be planned.

Trial registration

Current Controlled trials ISRCTN43801571, Dutch Trial Register NTR2138

The effect of physical exercise on cancer-related fatigue during cancer treatment: a meta-analysis of randomised controlled trials

The aim of this meta-analysis was to evaluate the effects of different exercise prescription parameters during cancer treatment on cancer-related fatigue (CRF). We also aimed to gain insight into the safety and feasibility of exercise during adjuvant cancer treatment. A systematic search of CINAHL, Cochrane Library, Embase, Medline, Scopus and PEDro was carried out. Randomised controlled trials studying the effects of exercise during cancer treatment on CRF were included. In total, 18 studies (12 in breast, four in prostate and two in other cancer patients) met all the inclusion criteria. During breast cancer treatment, home-based exercise lead to a small, non-significant reduction (standardised mean difference 0.10, 95% confidence interval -0.25 to 0.45), whereas supervised aerobic exercise showed a medium, significant reduction in CRF (standardised mean difference 0.30, 95% confidence interval 0.09 to 0.51) compared with no exercise. A subgroup analysis of home-based (n=65) and supervised aerobic (n=98) and resistance exercise programmes (n=208) in prostate cancer patients showed no significant reduction in CRF in favour of the exercise group. Adherence ranged from 39% of the patients who visited at least 70% of the supervised exercise sessions to 100% completion of a home-based walking programme. In more than half the studies (12 of 18; 67%) adverse events were reported. Eight events in total (0.72%) occurred in these studies.

Effect of exercise on postmenopausal sex hormone levels and role of body fat: a randomized controlled trial

PURPOSE

To examine the effects of a 1-year exercise intervention on sex hormone levels in postmenopausal women and whether any effects are mediated by changes in body fat composition.

METHODS

We randomly assigned 189 sedentary postmenopausal women (age 50 to 69 years, body mass index of 22 to 40 kg/m(2)) to an exercise intervention (n = 96) or a control group (n = 93). The intervention combined aerobic and strength training and comprised supervised group sessions and home-based exercises (a total of 2.5 h/wk). Between-group differences in sex hormone levels (at baseline and 4 and 12 months) were examined with generalized estimating equations.

RESULTS

In total, 183 women (97%) completed the study. Overall, the exercise intervention did not result in favorable effects on sex hormone levels. Among women who lost more than 2% body fat, declines in all estrogens were not significantly different between exercisers and controls. Androgen levels decreased significantly in the exercise group who lost body fat compared with their peers in the control group. Furthermore, this study confirmed that fat loss was significantly associated with declines in postmenopausal estrogen levels. Although not significant, a similar trend was observed for the androgens.

CONCLUSION

This study confirms that fat loss is associated with changes in postmenopausal sex hormone levels and suggests that exercise may be effective in inducing favorable changes in these hormones.