Cancer related fatigue (CRF) is still rated the most distressing side effect of all cancer therapies by patients and yet most of them do not receive any education or forewarning about fatigue.
Cancer related fatigue (CRF) is still rated the most distressing side effect of all cancer therapies by patients and yet most of them do not receive any education or forewarning about fatigue. According to Ahlberg, et al.,(2003), it is estimated that 70% -100% of all patients with cancer suffer from CRF which can be more distressing and disruptive to daily activities than pain. The National Comprehensive Cancer Network (NCCN) defines cancer related fatigue as an unusual, persistent, subjective sense of tiredness related to cancer or cancer treatment that interferes with usual functioning. Fatigue is not the same as tiredness. Tiredness happens to everyone, usually after activity or exercise and is relieved by sleep or rest. Fatigue, on the other hand, is a daily lack of energy that is not relieved from rest and not caused from activity or exercise. It can prevent a person from functioning normally and impacts their quality of life including mood, relationships, and job performance and is fairly constant. The specific mechanisms involved in the development of CRF are not completely known, but both physiologic and psychological factors seem to be involved.
Physiologic factors that can impact fatigue include anemia, loss of nutrients, tumor burden or cytokines. Contributing factors to anemia in CRF include hemorrhage, hemolysis, nutritional deficiencies and increased production of cytokines which cause a reduction in the production of erythropoietin. In addition, chemotherapy and radiation therapy can lead to anemia. Cachexia, anorexia, nausea, vomiting, or hypermetabolism can all lead to nutritional losses that contribute to CRF. The tumor burden itself can contribute to fatigue with a direct correlation between the tumor stage and the degree of fatigue.
Psychosocial factors can also contribute to cancer related fatigue. These include anxiety and depression, difficulty sleeping, and pain. In addition some patients continue to work full time in order to be able to keep insurance and pay for their treatment which can lead to increased fatigue. Often patients with cancer have a lower degree of physical functioning and activity level. Fatigue is inversely related to activity level.
So what can we do for our patients who are experiencing or at risk of experiencing fatigue? First we should be screening all patients for fatigue on a regular basis. The NCCN recommends to screen as a vital sign at regular intervals. For patients over the age of 12 a likert scale with 0 being no fatigue and 10 being the worst fatigue ever should be used. An alternative would be to use none, mild, moderate, and severe. For patients age 7-12 the scale should be from 1—5 with 1 being no fatigue and 5 being the worst fatigue. For those patients who are 5-6 years old the descriptors of tired or not tired are recommended. Once the screening has be completed, if there fatigue is none to mild, the recommendation is to educate the patient and provide general strategies to combat fatigue then continue with ongoing evaluation. For anyone who screens as moderate to severe, the education and interventions should be employed in addition to a primary evaluation. The primary evaluation includes a thorough assessment with a focused history that includes a review of systems, medication review, an in-depth fatigue history and assessment of disease status. Another important aspect of the primary evaluation is to assess for contributing factors. Once this is completed we should treat the contributing factors that are treatable such as pain, anemia, sleep, anxiety and activity. At this point, treatment should continue as needed with ongoing fatigue assessment.
There are a number of fatigue assessment tools available including the Brief Fatigue Inventory, numeric fatigue scales and others. The Oncology Nursing Society describes several of the most common tools.
After treating the contributing factors of fatigue such as anemia, what can we do about treating the fatigue itself? The ONS Putting Evidence Into Practice (PEP) project recommends the use of moderate exercise as an intervention to battle fatigue. Fourteen meta-analyses or systematic reviews support the use of exercise in managing fatigue both during and after treatment for cancer. Other interventions that ONS stats are likely to be effective based on evidence are screening for etiologic factors, energy conservation and activity management, education, optimizing sleep quality, relaxation, massage, healing touch, polarity therapy and haptotherapy. There are a variety of pharmacologic and non-pharmacologic interventions for which effectiveness has not been established thus far.
It is important for oncology nurses to be informed about the symptoms and side effects of disease and treatment that our patients most likely will experience. Using tools such as the ONS PEP resources and the NCCN clinical practice guidelines can only keep us more well informed but give us the tools we need to impact outcomes of our patients.