Evidence for classically conditioned fatigue responses in patients receiving chemotherapy treatment for breast cancer.
Fatigue is the most common side effect of chemotherapy for cancer. Not yet explored is the possibility that patients may develop conditioned fatigue responses to clinic cues as a result of the repeated pairing of the clinic environment (conditioned stimulus) with infusions of chemotherapy (unconditioned stimulus) that cause fatigue (unconditioned response). As a first critical test of this possibility, breast cancer patients (N = 82) were studied across their first four cycles of chemotherapy. Consistent with conditioning: (1) fatigue levels in the clinic environment significantly increased with repeated pairings of the clinic environment and chemotherapy administration; (2) fatigue responses in the clinic environment prior to the fourth infusion (CR) were predicted by patients' previous experiences of post-infusion fatigue (UR) above and beyond effects of concurrent emotional distress. These results provide the first evidence in the literature that fatigue can be conditioned. Additional research is warranted to determine the clinical importance of this source of fatigue in chemotherapy patients.
Bovbjerg
Dana H
DH
Department of Oncological Sciences, Mount Sinai School of Medicine, 1425 Madison Avenue, New York, NY 10029-6574, USA. dana.bovbjerg@mssm.edu
Montgomery
Guy H
GH
Raptis
George
G
D000970:Antineoplastic Agents / Q000009:adverse effects*; D001943:Breast Neoplasms / Q000188:drug therapy*; D003214:Conditioning, Classical; D005221:Fatigue / Q000139:chemically induced* / Q000523:psychology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012044:Regression Analysis
D000970:Antineoplastic Agents