Ecological momentary assessment of fatigue following breast cancer treatment.

Fatigue is a common and debilitating symptom often experienced during and following cancer treatment. An Ecological Momentary Assessment (EMA) approach was used to examine the diurnal pattern of off-treatment fatigue in breast cancer survivors. Twenty-five breast cancer (BC) survivors 6-26 months posttreatment and age-matched groups of healthy women (HC; n = 25) and women with benign breast problems (BBP; n = 24) completed four daily diary measures of fatigue, pain, and mood for 5 consecutive days. Type of activity engaged in at the time of the diary assessments, as well as daily pedometer activity level, and nightly sleep duration were also assessed. While BC survivors reported greater levels of fatigue relative to BBP anid HC groups, no group differences in mood, activity type or level, sleep duration, or diurnal pattern of fatigue were evident. The results confirm that fatigue mav continue to be experienced long after conclusion of cancer treatment while questioning its clinical significance, provide insight into potential etiological mechanisms underlying off-treatment fatigue in, and demonstrate the value of EMA approaches to the study of cancer-related fatigue.