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, ß = 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: ß = 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.

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

Perceived facilitators and barriers by esophageal cancer survivors participating in a post-treatment exercise program.

PURPOSE: Participation in a post-treatment exercise program improves cardiorespiratory fitness and aspects of quality of life for esophageal cancer survivors. For optimal effects, high adherence to the exercise intervention is important. We assessed which facilitators and barriers to exercise adherence are perceived by esophageal cancer survivors, who participate in a post-treatment exercise program. METHODS: The current qualitative study was performed within the randomized controlled PERFECT trial, in which we investigated effects of a 12-week supervised exercise program with moderate-to-high intensity and daily physical activity advice. Semi-structured interviews were conducted with patients randomized to the exercise group. A thematic content approach was used to derive perceived facilitators and barriers. RESULTS: Thematic saturation was reached after inclusion of sixteen patients. Median session attendance was 97.9% (IQR 91.7-100%), and relative dose intensity (compliance) to all exercises was ≥90.0%. Adherence to the activity advice was 50.0% (16.7-60.4%). Facilitators and barriers were captured in seven themes. The most important facilitators were patients' own intention to engage in exercise and supervision by a physiotherapist. Barriers were mainly experienced in completion of the activity advice, and included logistic factors and physical complaints. CONCLUSIONS: Esophageal cancer survivors are well capable to attend a moderate-to-high intensity post-treatment exercise program, and to fulfill the exercises according to protocol. This is facilitated by patients' own intention to engage in exercise and supervision of the physiotherapist, and only minimally affected by barriers as logistic factors and physical complaints. IMPLICATIONS FOR CANCER SURVIVORS: When implementing postoperative exercise programs in clinical care, it can be useful to be aware of perceived facilitators and barriers of cancer survivors in order to achieve optimal exercise adherence and maximize beneficial exercise effects. TRIAL REGISTRATION: Dutch Trial Register NTR 5045.

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.

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.

Participation in and adherence to physical exercise after completion of primary cancer treatment.

BACKGROUND: The purpose of this study was  to identify demographic, clinical, psychosocial, physical and environmental factors that are associated with participation in and adherence to a combined resistance and endurance exercise program among cancer survivors, shortly after completion of primary cancer treatment. Data from the randomized controlled Resistance and Endurance exercise After ChemoTherapy (REACT) study were used for this study. METHODS: The participants of the REACT study were randomly allocated to either a high intensity (HI) or low-to-moderate intensity (LMI) exercise program. Patients' participation rate was defined as the cancer survivors' decision to participate in the REACT study. Exercise adherence reflected participants' attendance to the scheduled exercise sessions and their compliance to the prescribed exercises. High session attendance rates were defined as attending at least 80 % of the sessions. High compliance rates were defined as performing at least of 90 % of the prescribed exercise across all sessions. Correlates of exercise adherence were studied separately for HI and LMI exercise. Demographic, clinical, and physical factors were assessed using self-reported questionnaires. Relevant clinical information was extracted from medical records. Multivariable logistic regression analyses were applied to identify correlates that were significantly associated with participation, high session attendance, high compliance with resistance and high compliance with endurance exercises. RESULTS: Participants were more likely to have higher education, be non-smokers, have lower psychological distress, higher outcome expectations, and perceive more exercise barriers than non-participants. In HI exercise, higher self-efficacy was significantly associated with high session attendance and high compliance with endurance exercises, and lower psychological distress was significantly associated with high compliance with resistance exercises. In LMI exercise, being a non-smoker was significantly associated with high compliance with resistance exercises and higher BMI was significantly associated with high compliance with resistance and endurance exercises. Furthermore, breast cancer survivors were less likely to report high compliance with resistance and endurance exercises in LMI exercise compared to survivors of other types of cancer. The discriminative ability of the multivariable models ranged from 0.62 to 0.75. CONCLUSION: Several demographic, clinical and psychosocial factors were associated with participation in and adherence to exercise among cancer survivors. Psychosocial factors were more strongly associated with adherence in HI than LMI exercise. TRIAL REGISTRATION: This study was registered at the Netherlands Trial Register [ NTR2153 ] on the 5(th) of January 2010.