Exercise Boosts Quality of Life for Metastatic Breast Cancer Patients

Overview

A recent large-scale study has found that a structured and personalized exercise program can significantly improve the quality of life and reduce fatigue in patients with advanced, or

, breast cancer. The study, called the PREFERABLE-EFFECT trial, involved 357 patients from multiple countries who were randomly assigned to either participate in a 9-month exercise program or receive general physical activity advice.

The researchers found that the patients who took part in the exercise program experienced notable improvements in their overall quality of life, as well as substantial reductions in physical fatigue, compared to the control group. These benefits were seen both during the fully supervised exercise period and the maintenance period where participants had a mix of supervised and unsupervised sessions.

This study is the first adequately powered trial to examine the effects of exercise on quality of life and fatigue in patients with metastatic breast cancer, a population that often struggles with low physical functioning and high levels of debilitating symptoms like fatigue, pain, and shortness of breath. The findings suggest that incorporating a supervised,

into the supportive care for these patients could have significant positive impacts on their well-being and ability to manage their disease.

Study Design and Participants

The PREFERABLE-EFFECT study was a multinational randomized controlled trial that enrolled 357 patients with stage IV breast cancer. The participants were 18 years or older, had an

of 2 or less (indicating they were relatively well), and were able and willing to take part in the exercise program and wear an activity tracker.

The patients were randomly assigned in a 1:1 ratio to either the exercise group or the control group. The exercise group participated in a 9-month structured and individualized exercise program, while the control group received general physical activity advice in addition to their usual care, but no formal exercise program.

The exercise program consisted of supervised, multimodal exercise sessions that combined

,

aerobic exercise

Physical activities that increase your heart rate and breathing, such as walking, running, or swimming, to improve cardiovascular fitness.

 

, and balance exercises. For the first 6 months, participants had two 1-hour supervised sessions per week. In the last 3 months, one of the supervised sessions was replaced with an unsupervised session to help participants transition to maintaining the exercise routine on their own.

The intensity of the exercises was tailored to each participant's fitness level and health status. All participants, regardless of group, were provided with an activity tracker to monitor their physical activity levels throughout the study.

Primary Outcomes and Findings

The two primary outcomes measured in the study were:

1. Health-related quality of life (
   HRQOL
   An abbreviation for 'health-related quality of life,' which refers to a person's overall physical, mental, and social well-being related to their health condition.

    
   ), assessed using the summary score of the
   EORTC QLQ-C30 questionnaire
   A survey used to measure the quality of life of cancer patients, covering areas like physical, emotional, and social well-being.

    
   .
2. Cancer-related physical fatigue, assessed using the physical fatigue dimension of the
   EORTC QLQ-FA12 questionnaire
   A survey that specifically assesses cancer-related fatigue, which is a common symptom experienced by cancer patients.

    
   .

The researchers found that the exercise group experienced significant improvements in overall quality of life, with differences ranging from 3.9 to 4.8 points compared to the control group. Additionally, the exercise group showed substantial reductions in physical fatigue, with differences of -3.4 to -5.6 points compared to the control group.

These findings indicate that the exercise program had a clinically meaningful and statistically significant positive impact on both the quality of life and fatigue levels of the patients in the exercise group.

Secondary Outcomes and Other Findings

In addition to the primary outcomes, the researchers also examined several secondary outcomes, including:

• Other HRQOL measures, such as global quality of life, physical functioning, and social functioning
• Other fatigue dimensions
• Physical activity levels
• Physical fitness

The results showed that the exercise intervention had significant and clinically relevant positive effects on these additional outcomes as well. The exercise group demonstrated improvements in physical functioning, social functioning, and reductions in symptoms like pain and shortness of breath compared to the control group.

Importantly, the majority of participants in the study had clinically low levels of physical functioning and high levels of fatigue, pain, and shortness of breath at the start of the study. This indicates that this patient population was in need of an intervention like the exercise program provided in the PREFERABLE-EFFECT trial.

Strengths and Limitations

A key strength of this study is that it was the first adequately powered trial to examine the effects of exercise on quality of life and fatigue in patients with metastatic breast cancer. The large, multinational sample size and the use of validated, standardized outcome measures increase the reliability and generalizability of the results.

However, the study also had some limitations. The inability to blind participants to their group assignment may have motivated the control group to increase their physical activity levels, potentially underestimating the true impact of the exercise intervention. Additionally, the 40% recruitment rate and potential self-selection bias of the participants may limit how representative the study sample is of the broader population of patients with advanced breast cancer.

To address these potential limitations, the researchers conducted

to examine the influence of various factors, such as age, baseline fitness and depression levels, and tumor characteristics, on the intervention effects. They also performed sensitivity analyses using

multiple imputation methods

A statistical technique used to estimate missing data in a dataset, which helps ensure the accuracy of the study's results.

 

to assess the robustness of the results.

Conclusion and Implications

The PREFERABLE-EFFECT study provides compelling evidence that a supervised, multimodal exercise program can significantly improve the quality of life and reduce fatigue in patients with stage IV breast cancer. This is an important finding, as this patient population often struggles with debilitating symptoms that can greatly impact their daily functioning and well-being.

Based on these results, the authors recommend that supervised resistance and aerobic exercise be integrated into the supportive care for patients with metastatic breast cancer. Incorporating such an exercise program could help these individuals better manage their disease and maintain a higher quality of life throughout their treatment and care.

Overall, this study represents an important step forward in understanding how exercise can be leveraged as a supportive therapy for patients with advanced cancer. The findings highlight the potential for exercise to play a crucial role in improving the comprehensive care and outcomes for this vulnerable patient population.