9090 Background: Fatigue is one of the most frequently reported and aversive side effects of cancer chemotherapy. Prospective research has found that cancer patients’ levels of emotional distress prior to treatment are predictive of other side effects (e.g., nausea), but studies of such effects on fatigue are lacking. The present study prospectively tested the hypothesis that patients’ levels of emotional distress in the clinic prior to their first treatment infusion would predict the severity of their post-infusion fatigue. Methods: Sixty Stage I (32.6%) and II (67.4%) breast cancer patients (mean age=44.5 yrs), receiving standard outpatient chemotherapy (e.g., CMF), participated. The independent variable, emotional distress, was assessed (0–100) with a visual analog scale (VAS). The dependent variable, post treatment fatigue (PTF) was assessed (0–100) over each of the subsequent 6 days using end-of-day diaries, which also included assessment of distress (0–100). To explore temporal specificity, pretreatment distress was assessed for “last night”, “this morning” and “right now.” Results: Consistent with previous reports, PTF levels peaked at day 2 and began to decline after day 3, although they remained elevated across the period (p<.026). Repeated measures analysis indicated a significant main effect of pretreatment distress “right now” on PTF (p<.009); prior distress levels were less predictive. Additional regression analyses, controlling for pretreatment fatigue and daily distress, revealed a strongly selective effect of pretreatment distress on post peak PTF on days 5 (p<.002) and 6 (p<.026). Conclusions: This study is the first to demonstrate time-specific effects of pretreatment distress on PTF. Possible mechanisms of these effects now warrant investigation, as do possible benefits of brief interventions to reduce distress immediately prior to treatment. No significant financial relationships to disclose.
