Study takes a step toward better defining fatigue

May 15, 2008

In an effort to better define and ultimately address fatigue more effectively, a qualitative study from The University of Texas M. D. Anderson Cancer Center has identified three primary themes - loss of strength or energy, major effects of fatigue and associated sensations - among patients being treated with standard radiation therapy.

Presenting today at the 33rd Annual Congress of the Oncology Nursing Society (ONS), Loretta A. Williams, Ph.D., RN, AOCN, OCN, an instructor in the Department of Symptom Research at M. D. Anderson, detailed commonalities of 21 patients who shared personal stories of dealing with cancer's most distressing and common symptom.

"While fatigue is a well-recognized symptom of cancer and its treatment, the measurement of fatigue has been based on many different ideas and definitions. Few of these definitions have included patient input. We're trying to define fatigue based on patient experience," said Williams. "Once we're able to determine the critical elements of fatigue, we'll be better equipped to ask the right questions of patients to assess fatigue. Healthcare professionals - including nurses - will be in a much better position to intervene with patients to manage or prevent fatigue."

The study included open-ended, audio-taped interviews with 21 patients, all who were receiving radiation therapy at M. D. Anderson. The patients were evenly divided with diagnoses of breast, prostate and head and neck cancer. Of the 21 patients who were interviewed during the fifth week of radiation therapy, 57 percent were women and the average patient was 54 years old.

In the study, patients reported a loss of strength or energy that included feelings of tiredness or weakness, which may progress to exhaustion, and lack of energy and stamina.

Because of the qualitative technique that Williams and her team used, their dialogues with patients revealed comments such as, "I don't have a body part that is tired. My whole body is tired," "I just have a weak feeling...pretty well all over," and "Fatigue to me is just a feeling of no energy."

More than 85 percent of the patients in Williams' study used the terms, "tiredness" and "lack of energy" to describe fatigue. According to the researchers, these may be good terms for patients to use when speaking with health care providers about fatigue and terms that should alert the providers to patients experiencing it.

The team also reported that the effects of fatigue included a lack of motivation or inability to perform usual activities, decreased interest in social activities, and an overwhelming need to rest at times.

"Among the patients that we talked to, they often expressed an inability to do things that they could easily do before their treatment or before their diagnosis," said Williams. "They frequently reported that they didn't want to be around others, that it took too much out of them to keep up a conversation or be cordial."

Williams and her team also pinpointed physical sensations associated with fatigue that included, "malaise, aching, feelings of heaviness or weight, slowness of movement, lack of appetite, and mental sensations of psychological distress and difficulty thinking or concentrating."

One patient described the physical sensations as "a feeling of heaviness," while another said, "I just felt myself dragged out, just tired, and it was distressing to me because that's not my norm. I don't like to feel like that."

"Defining the patient's experience with a symptom is critical to assessing and managing that symptom," said Williams who was a clinical nurse specialist before joining M. D. Anderson's Department of Symptom Management as a nurse-scientist. "Assessing and managing symptoms, certainly fatigue, is a primary role of oncology nurses."

Williams and her team are planning similar future studies to better define fatigue among patients receiving chemotherapy and new targeted therapies. They plan to develop a single definition of cancer-related fatigue.

Source: University of Texas