Short Communication, J Pharm Sci Emerg Drugs Vol: 9 Issue: 12
Meta analysis of randomized controlled trials examining physical activity in cancer survivors
Cancer survivors who have successfully completed their primary cancer treatment often expect to resume their work or daily life at a level similar to that before the cancer diagnosis. While cancer treatment has been shown to be effective in prolonging survival, it can be intensive and can lead to increased fatigue, decreased physical activity, and a reduction in quality of life. In addition, these unwanted effects of treatment can be prolonged and hinder the patients�?? return to normal life. Physical activity is a potentially appealing intervention that could alleviate related to cancer and assist patients in returning to the health status they had before treatment. A systematic review published in 2005 summarised the evidence supporting the recommendation of physical activity during and after treatment related to cancer and a meta-analysis published in 2006 reported more favourable outcomes when physical activity was carried out after treatment. In a recent study published in 2011, starting an exercise programme after the completion of treatment was shown to be acceptable to over three quarters of patients. Several randomised controlled trials have assessed the efficacy of physical activity on indicators of physical and mental health in patients after cancer treatment, and these trials reported significant improvement after physical activity. The effects of physical activity on cancer have been examined in nine meta-analyses, with three focusing on breast cancer and six on any type of cancer. Moreover, more randomised controlled trials have been published since the publication of the last meta-analysis in 2011. We updated the most recent meta-analysis by including studies published more recently and included only randomised controlled trials. Using data from randomised controlled trials, we evaluated the best current evidence for the effects of physical activity on physical functions, physiological parameters, body composition, psychosocial outcomes, and quality of life in adult patients after they had completed their main treatment related to cancer. Discussion In patients who have completed treatment for cancer, physical activity is associated with significantly reduced insulin-like growth factor-I, BMI, body weight, fatigue, and depression; it is also associated with increased peak oxygen consumption, peak power output, distance walked in six minutes, bench and leg press weight, right handgrip strength, and quality of life in the physical function, social function, and mental health domains. We reviewed 48 outcomes reported from 34 randomised controlled trials in patients with cancer. The effects were clinically important to physical functions and quality of life. We found substantial study heterogeneity, which was attributed to study quality and size, patients�?? age, and type and duration of physical activity. Based on data from four randomised controlled trials in breast cancer, physical activity was associated with significantly reduced serum concentration of insulin-like growth factor-I, despite insignificant results being reported in the primary studies. This was because of the increased precision resulting from combining different studies. A recent meta-analysis that pooled three of the studies we included also reported a small reduction in insulin-like growth factorI. Another meta-analysis that examined physiological changes after exercise reported that the effect of physical activity was insignificant. Thus, a significant reduction in insulin-like growth factor by aerobic or weight training could potentially imply a reduced risk of cancer recurrence. However, there was no clear trend of an effect of physical activity on blood insulin, glucose, and homeostatic model assessment levels. BMI and body weight were found to be slightly but significantly reduced after physical activity intervention in studies that included patients with any cancer or breast cancer. The same result was found in the most recent meta-analysis, which also reported significant but not clinically important effects. None of the other body parameters was significantly improved by physical activity. This finding is consistent with the literature, although previous meta-analyses have shown that percentage of body fat and lean body mass were significantly improved. These meta-analyses, however, also included studies assessing physical activity during cancer treatment or did not show a clinically important effect. Physical activity after completion of cancer treatment had clear benefits for many physical functions, including peak oxygen consumption, peak power output, distance walked in six minutes, and bench and leg press weights. Except for those of bench and leg presses, these findings have also been consistently reported in all other meta-analyses. The only meta-analysis that reported unstandardized effects showed a slightly larger effect than ours on peak oxygen consumption and distance walked in six minutes. That meta-analysis, however, included only studies on patients with breast cancer, who might carry out physical activity during and after treatment. A significant but small reduction in fatigue was observed in breast cancer studies using the revised Piper fatigue scale but not in studies on any cancer using either of the other two fatigue scales. Both the revised Piper fatigue scale and functional assessment of cancer therapy-fatigue have been shown to perform satisfactorily in measuring cancer related fatigue
Abstract
Cancer survivors who have successfully completed their primary cancer treatment often expect to resume their work or daily life at a level similar to that before the cancer diagnosis. While cancer treatment has been shown to be effective in prolonging survival, it can be intensive and can lead to increased fatigue, decreased physical activity, and a reduction in quality of life. In addition, these unwanted effects of treatment can be prolonged and hinder the patients’ return to normal life. Physical activity is a potentially appealing intervention that could alleviate related to cancer and assist patients in returning to the health status they had before treatment. A systematic review published in 2005 summarised the evidence supporting the recommendation of physical activity during and after treatment related to cancer and a meta-analysis published in 2006 reported more favourable outcomes when physical activity was carried out after treatment. In a recent study published in 2011, starting an exercise programme after the completion of treatment was shown to be acceptable to over three quarters of patients. Several randomised controlled trials have assessed the efficacy of physical activity on indicators of physical and mental health in patients after cancer treatment, and these trials reported significant improvement after physical activity. The effects of physical activity on cancer have been examined in nine meta-analyses, with three focusing on breast cancer and six on any type of cancer. Moreover, more randomised controlled trials have been published since the publication of the last meta-analysis in 2011. We updated the most recent meta-analysis by including studies published more recently and included only randomised controlled trials. Using data from randomised controlled trials, we evaluated the best current evidence for the effects of physical activity on physical functions, physiological parameters, body composition, psychosocial outcomes, and quality of life in adult patients after they had completed their main treatment related to cancer.
