Fatigue Difficult to Isolate From Related Cancer Symptoms

PHILADELPHIA—A study presented at the Oncology Nursing Society’s 26th Annual Congress in San Diego underscores the challenge of managing cancer-related fatigue: Fatigue frequently is part of a cluster of interrelated symptoms, such as pain, depression, and poor sleep quality.

Andrea M. Barsevick, DNSc, RN, director of nursing research and education, Fox Chase Cancer Center, and her colleagues examined the effects of symptom clustering in a group of 101 patients who were drawn from the control group of a larger study of fatigue management.

The study group was composed of 89 women and 12 men, with a mean age of 57 (range, 30 to 78). The majority of patients had breast cancer, but other diagnoses included cervical cancer, lymphoma, and lung cancer. All disease stages were represented in the group.

The investigators measured fatigue, pain, depression, and sleep quality at baseline and at a time of expected high fatigue (at the end of 5 weeks of radiation therapy or 48 hours after the second cycle of chemotherapy).

Fatigue was measured with the Profile of Mood States (fatigue scale), the Schwartz Cancer Fatigue Scale, and the General Fatigue Scale.

Sleep quality was assessed with the Pittsburgh Sleep Quality Scale; depression, with the Profile of Mood States (depression scale); and pain, with a Side Effects Checklist item (pain).

When the symptoms were considered individually, 36% of the study participants experienced pain; 82% had sleep disturbances; 22% experienced depression; and 81% experienced fatigue.

When the symptoms were grouped as triads, 7% of the patients had fatigue-pain-depression; 21% had fatigue-pain-sleep disturbance; 7% experienced pain-sleep disturbance-depression; and 21% had fatigue-sleep disturbance-depression. Seven percent of the patients experienced all four symptoms.

The investigators concluded that symptom clustering is common among patients undergoing cancer treatment and that fatigue is significantly correlated with depression. Poor sleep quality also was associated with fatigue, but the relationship did not reach statistical significance.

The study did not find a correlation between fatigue and pain, but the researchers noted that the pain measurement may not have been sensitive enough.