|
Article Excerpt
The incidence of fatigue among patients with cancer is well-documented, with 75%-99% of patients who undergo chemotherapy describing it as increasing with every cycle (Nail & Jones, 1995). Similarly, 69% of patients receiving radiation therapy report increased fatigue with each treatment (Stone, Richards, A'Hearn, & Hardy, 2001). Hence, fatigue has been the most commonly occurring symptom of cancer and cancer treatment (McCance & Barnette, 2006).
Fatigue is a subjective experience encompassing weariness, tiredness, or lack of energy (Dimeo, 2001). Every person experiences fatigue, which is a protective mechanism normally relieved by a good night's sleep (Piper, Lindsey, & Dodd, 1987). Cancer-related fatigue is defined by the National Comprehensive Cancer Network (NCCN) as "a distressing and persistent, subjective sense of physical, emotional and/or cognitive tiredness related to cancer or cancer treatment that is not proportional to recent activity and that interferes with usual functioning" (Mock et al., 2005; NCCN, 2009, p. FT-1). It is a debilitating and complex symptom in patients with advanced cancer, and is chronic, persistent, profound, and usually unrelieved by rest (Headley, Ownby, & John, 2004). Perceptions differ among researchers as to the definition and measurement of fatigue. Some do not define fatigue as a single entity; instead, they group it with other symptoms as a component of quality of life (QOL) or measure it in comparison with usual energy (Borthwick, Knowles, McNamara, O'Dea, & Stroner, 2003; Coleman, Coon, Mattox, & O'Sullivan, 2002; Courneya et al., 2003; Pickett et al., 2002; Pinto, Frierson, Rabin, Trunzo, & Marcus, 2005). Winningham (1999) suggested that fatigue be considered a syndrome, or phenomenon, rather than a side effect because of its many dimensions and possible causes. Emphasizing the importance of fatigue for nursing care, Winningham further noted fatigue remains subjective due to lack of definitive diagnostic indicators for detection and monitoring.
Although research increasingly has shown fatigue to be a frequent and troublesome side effect of cancer and its treatment, little of this research has paved the way to improved clinical care of patients with cancer experiencing fatigue. Because fatigue was considered untreatable, its assessment and recommendations to alleviate it still were unapparent in practice as recently as the late 1990s (Nail, 2002). However, research has shown exercise increases the efficiency of the cardiovascular, pulmonary, and endocrine systems; enhances muscular endurance; improves flexibility; and decreases emotional stress and pain (Evans & Lambert, 2007). More significantly, research demonstrates that exercise decreased the duration of neutropenia and thrombocytopenia in patients with cancer (Battaglini, 2004; Visovsky & Dvorak, 2005). The purpose of this systematic review is to investigate the relationship between fatigue and exercise among patients receiving chemotherapy and/or radiation.
Methods
A systematic review was conducted based on guidelines and steps outlined by Forbes (2003). First, a focused question was formulated: "What is the relationship between cancer treatment fatigue and exercise?" Following this step, criteria for literature search were developed to include all primary research published between January 2000 and October 2006, in English, in peer-reviewed nursing and health care journals, and with subjects age 18 or older. A literature search conducted in October 2006 using the CINAHL[R], Medline[R], Ovid[R], and ProQuest[R] databases yielded over 400 articles addressing the topics of fatigue, cancer, and exercise. Three unpublished doctoral dissertations also were evaluated for possible inclusion; two of them met the criteria. Both quantitative and qualitative studies were included. Based on these criteria, 10 studies were selected for inclusion in the systematic review. These studies then were evaluated based on the PICO outline (Mulrow & Cook, 1998): population (sample characteristics, age, gender, type of cancer), interventions (efficacy of the intervention), control versus experimental groups, and outcomes. Designs, limitations, and recommendations of each study also were reviewed. The levels of evidence presented in these studies were established using the Priority Symptom Management (PRISM) initiative developed by the Oncology Nursing Society (Ropka & Spencer-Cisek, 2001) to guide evidence-based research in the area of symptom management (see Table 1).
Results
The results of the systematic review of the 10 studies (most current to oldest) are shown in a grid format in Table 2. The grid shows the designs, population characteristics (gender, type of cancer, treatment modalities), interventions (duration and types of exercise, comparison groups), outcomes, limitations of the studies, levels of evidence, and recommendations. Sample size of the studies ranged from 12 to 108. The level of evidence provided by these studies was moderate to high; three of the studies had a level of evidence of 1 (systematic reviews and/or meta analysis) and 2 (randomized controlled study). Another three had a level of evidence of 5 (well-conducted case controlled study), and one study had a level of evidence of 3 (well-designed study clinical trial without randomization). Types of cancer reported by participants were mixed, including multiple myeloma, and breast, lung,...
|
