The number of adults over 65 years of age is increasing more rapidly than any other age group, with those over 80 growing the fastest and expected to account for 20% of people over 65 by the year 2050 (31
). Cancer is a disease that disproportionally affects those over the age of 65 (32
). To our knowledge, this is one of the few studies to focus on symptom severity, self-rated health and exercise participation in older cancer patients undergoing chemotherapy and/or radiation therapy and one of the few that provides data on cancer patients 80 years of age and older. Overall, these data suggest that many older cancer patients are interested in and able to exercise during treatment for cancer, as nearly half of the cancer patients age 65 and older in this study reported using exercise during treatment. Following treatment, over half of patients over 65 years of age reported using exercise. In addition, nearly half of patients 80 and older reported exercising during treatment, and over half reported using exercise following treatment. In a sample of stage I-IIIa breast cancer patients of all ages, Irwin et al. reported a reduction in physical activity from pre to post-diagnosis of 14% and 9%, respectively (33
). Pinto and colleagues also found that breast cancer patients who were younger and farther out from diagnosis were more likely to exercise (34
In general, older patients who reported using exercise during and following treatment reported less severe symptoms during and following treatment. Specifically, certain subsets of older patients who used exercise reported less shortness of breath, weight loss, fatigue, and total symptom burden during and following treatment. However, previous research has shown that co-morbidities, physical declines with aging, and physical limitations and symptoms resulting from treatment serve as barriers to exercise participation (35
), so it may be that those who have more severe symptoms are less likely to exercise. These data are not definitive for causality, but rather show an association between exercise and symptom severity. Other researchers have found exercise beneficial for the reduction of symptoms, but these studies, especially in older cancer patients, are limited in number.
Dyspnea at rest or during exertion is a symptom experienced by some cancer patients (36
). Exercise interventions in lung cancer patients in particular have resulted in less breathlessness (37
). Sarcopenia is a type of muscle loss characterized by muscle fiber atrophy that occurs with age(38
) . Cancer cachexia is another troubling side effect of cancer and its treatment affecting an estimated 2 to 15% of cancer patients (39
). Exercise is a promising intervention for the reduction of both sarcopenia and cancer cachexia (40
). Cancer-related fatigue is a common symptom in cancer patients of all ages (43
).Cancer-related fatigue can be reduced in cancer patients between ages 21 and 65 (45
) but until recently, little was known about the relationship between physical activity and fatigue in cancer patients 65 years of age and older. Luctkar-Flude and colleagues have found that higher physical activity levels predict lower fatigue levels in older cancer survivors (47
), however few studies have focused on older cancer patients. Patients who exercised also reported better self-rated health than those who did not use exercise during or following treatment. Self-rated health has been found to be a predictor of mortality, independent of health status (48
Research to assess why some cancer patients exercise and others do not is necessary. Research is desperately needed to determine the safety and efficacy of exercise in older cancer patients and survivors. Feasibility studies to assess intensity and dose of exercise needed for these patients and survivors to benefit from a reduction in symptom burden are also warranted. Exercise interventions must be designed to meet the unique needs of older cancer survivors and should be easily disseminated to all patients, regardless of social economic status and geographic location. Interventions that can be performed at retirement and assisted living communities may be of the greatest value and using modes of delivery that provide motivation and feedback, such as exergames, are promising interventions for this population. Lastly, research into the relationship between exercise and overall survival in older cancer patients is needed.
This study had a number of strengths in that it was conducted prospectively and systematically in one of the largest samples of older cancer patients to date. Moreover, it was conducted in multiple CCOP sites, thus increasing the generalizability of the data. However, there were some limitations. For example, the question used to ascertain the use of exercise during treatment did not provide any information on exercise type or dose. Additionally, a number of factors could have affected whether cancer patients participated in exercise during or following chemotherapy, radiation therapy or both. For example, information on cancer stage was not obtained, which may have affected exercise participation and symptoms. Although we found no significant difference in Karnofsky performance status between those who exercised and those who did not, a randomized controlled trial is needed to further investigate these relationships. Too, it may be that symptom presence or absence influences participation in exercise rather than exercise participation influencing symptoms. These patients represent a select group who are willing and able to participate in a clinical trial, perhaps limiting the generalizability of this investigation.
As the population ages, physicians will increasingly be faced with the challenges of managing the symptoms and side effects of cancer treatment in elderly populations. Exercise may be a promising strategy to reduce multiple symptoms and side effects with a single intervention. However, there is little data on the prevalence of participation of exercise in community-dwelling older adults during cancer treatment. The objective of this study was to evaluate the prevalence of exercise participation in older patients and to examine associations between exercising and treatment symptoms and self-rated health.
In conclusion, this investigation suggests that many older cancer patients are willing and able to use exercise during treatment. Evidence supporting the benefits of exercise for reducing symptom severity will likely increase the proportion of older adults willing to exercise during treatment. However, we must develop evidence-based exercise interventions that are proven to be effective for side-effect management in older cancer survivors. Ascertaining the type/s and dose of exercise that are most beneficial for reducing specific symptoms while developing exercise interventions that patients enjoy must be a priority given the growing number of older cancer survivors in the United States.