Gokal, K., Munir, F., Ahmed, S., Kancherla, K., & Wallis, D. (2018). Does walking protect against decline in cognitive functioning among breast cancer patients undergoing chemotherapy? Results from a small randomised controlled trial. PLOS ONE, 13, e0206874.

Assess the preliminary effectiveness of moderate-intensity walking, compared to usual care, on cognitive function during chemotherapy for non-metastatic, invasive breast cancer.

The intervention included two groups: moderate-intensity walking (targeting a self-managed goal of 150 minutes over 12 weeks) versus usual care.

Participants randomly assigned to the moderate-intensity walking group were given a booklet promoting reaching of the goal through self-management, starting with at least 10 minutes of walking and moving up to 30 minutes 5 days per week over 12 weeks. Participants were given a pedometer and were asked to record daily steps and complete the Borg Rating of Perceived Exertion Scale in a daily diary. Participants were also asked to log their weekly goals. 

Participants assigned to the usual care group received no intervention.

Study assessments were done pre-chemotherapy (familiarization, no data collected); midway through chemotherapy (pre-randomization); and after chemotherapy (i.e., postintervention).

• N = 50
• MEAN AGE: 52 years (SD = 10.4) 
• FEMALES: 100%
• CURRENT TREATMENT: Chemotherapy
• KEY DISEASE CHARACTERISTICS: Initial diagnosis of non-metastatic, invasive breast cancer (stage I-III)
• OTHER KEY SAMPLE CHARACTERISTICS: Undergoing neo-adjuvant (18%) or adjuvant (82%) chemotherapy with FEC with or without taxotere, reported less than 150 minutes of moderate-intensity activity per week, aged 18-75, 62% postmenopausal, race/ethnicity not reported, 44% completed college

• SITE: Single site   
• SETTING TYPE: Home    
• LOCATION: England, UK

PHASE OF CARE: Active anti-tumor treatment

Unblinded randomized controlled trial of moderate-intensity walking versus usual care with pre-/post- assessments

• Objective cognitive function: Battery of tests of executive function, working memory, attention, visuospatial skills
• Self-reported cognitive function: Cognitive Failures Questionnaire
• Other measures: Physical activity (accelerometer [data not usable], pedometer, perceived exertion), psychosocial patient-reported outcomes (results reported elsewhere)

• Feasibility: 79% completed the study, 80% in intervention group met goal of 150 minutes per week of moderate-intensity walking (no significant difference in minutes walked between week 1 and week 12); adverse events not reported
• Cognitive impairment: Self-reported cognitive failures were lower in the intervention group at baseline and did not worsen during the walking intervention, while the usual care group started with more self-reported cognitive failures that worsened with time (p = 0.05). Greater levels of physical activity were associated with fewer cognitive failures (p = 0.05). No group x time effects were found for any domain of objective cognitive function. The physical activity group had better working memory overall than the control group (p < 0.001), and all participants improved in working memory over time (p = 0.03). 
• Other outcomes: No associations were found between psychosocial patient-reported outcomes and cognitive function.

This  study provides evidence that a self-managed, home-based walking program of moderate-intensity is feasible during chemotherapy and may reduce declines in self-reported cognitive function during treatment.

• Small sample (< 100)
• Baseline sample/group differences of import
• Risk of bias (no blinding)
• Risk of bias (no appropriate attentional control condition)
• Findings not generalizable
• Subject withdrawals ≥ 10%  
• Other limitations/explanation: The participants in the intervention group reported fewer cognitive failures at baseline than the control group (potential ceiling effect for self-reported cognitive function). Generalizability unclear with no attention control and limited to women with stage I-III breast cancer.

This study provides preliminary evidence that self-managed, moderate-intensity walking might improve self-reported cognitive function, which is commonly reported to be impaired by breast cancer survivors. The findings support future well-powered studies evaluating walking to improve cognitive function.