Age-related differences in exercise and quality of life among breast cancer survivors.

PURPOSE: Physical activity has become a focus of cancer recovery research because it has the potential to reduce treatment-related burden and to optimize health-related quality of life (HRQoL). However, the potential for physical activity to influence recovery may be age dependent. This article describes physical activity levels and HRQoL among younger and older women after surgery for breast cancer and explores the correlates of physical inactivity. METHODS: A population-based sample of breast cancer patients (n = 287) diagnosed in South-East Queensland, Australia, were assessed once every 3 months, from 6 to 18 months postsurgery. The Functional Assessment of Cancer Therapy-Breast questionnaire and items from the Behavioral Risk Factor Surveillance System questionnaire were used to measure HRQoL and physical activity, respectively. Physical activity was assigned MET values and categorized as <3, 3 to 17.9, and 18+ MET x h x wk. Descriptive statistics, generalized linear models with age stratification (<50 vs 50+ yr), and logistic regression were used for analyses (P = 0.05, two-tailed). RESULTS: Younger women who engaged in >or=3 MET x h x wk of physical activity reported a higher HRQoL at 18 months compared with their more sedentary counterparts (P < 0.05). Older women reported similar HRQoL irrespective of activity level and consistently reported clinically higher HRQoL than younger women. Increasing age, being overweight or obese, and restricting use of the treated side at 6 months postsurgery increased the likelihood of sedentary behavior (odds ratio >or= 3, P < 0.05). CONCLUSIONS: Age influences the potential to observe HRQoL benefits related to physical activity participation. These results also provide relevant information for the design of exercise interventions for breast cancer survivors and highlight that some groups of women are at greater risk of long-term sedentary behavior.

Level of physical activity and characteristics associated with change following breast cancer diagnosis and treatment.

OBJECTIVE: While the physical and psychosocial benefits of participating in physical activity (PA) during and following breast cancer treatment are well understood, less is known about rates and uptake of PA following diagnosis. This paper explores the levels and patterns of PA among women recently diagnosed with breast cancer and the factors associated with change in activity levels. METHODS: Using a population-based recruitment approach, PA levels of 287 breast cancer patients were assessed at 6, 12 and 18 months post-diagnosis using the Behavioral Risk Factor Surveillance System, and then converted to MET (metabolic equivalent task)-hours/week. Regression analyses were used to explore the correlates associated with change between 6 and 18 months post-diagnosis. RESULTS: Although more than 80% of women participated in PA at each testing phases, more than 50% were considered insufficiently active or sedentary according to national recommendations and less than one-third reported engagement in vigorous or strength activities. Mean change in total MET-hours/week between 6 and 18 months post-diagnosis was minor (mean=0.10, median=0.0), however individual changes were substantial (ranging from -100 to +174 MET-hours/week). Results are more encouraging for the lower threshold of 3+ MET-hours/week, which may be most relevant specifically for breast cancer outcomes. CONCLUSIONS: Since the majority of women report insufficient levels of PA, there is a clear need for exercise interventions during and following breast cancer treatment. Few characteristics predict declines or improvements in PA levels, hence for optimal benefit, interventions should target the entire breast cancer population.