Fatigue increases following breast cancer treatment initiation

Patients with breast cancer experience clinically relevant fatigue for up to 2 years after treatment initiation, according to a study.

The study included 381 women (mean age 54 years, 75.9 percent White), of whom 236 had stage I–III breast cancer who received potentially cardiotoxic chemotherapy or aromatase inhibitors and 145 were female family or friends without a history of cancer, breast surgery, or chemotherapy (noncancer comparators).

Fatigue was assessed using the Functional Assessment of Chronic Illness Therapy Fatigue scale. Other outcome measures were sociodemographic variables, haematocrit, left ventricular ejection fraction and circumferential strain, cardiovascular comorbidities, 6-minute walk distance, perceived stress, and depressive symptoms.

In the breast cancer group, 117 women received chemotherapy inclusive of doxorubicin along with other chemotherapy agents or an aromatase inhibitor (AI) (chemotherapy inclusive of doxorubicin), 84 received chemotherapy possibly with an AI but without doxorubicin (chemotherapy without doxorubicin), and 35 received an AI only.

Two years after breast cancer treatment, 18.2 percent of patients receiving potentially cardiotoxic chemotherapy had clinically relevant fatigue, and 34.6 percent experienced a significant increase in fatigue relative to their precancer treatment fatigue level.

Twenty-four-month post-breast cancer treatment fatigue was associated with and mediated by depressive symptoms (estimate, −0.77, 95 percent confidence interval [CI], −0.83 to −0.71; p<0.001) and perceived stress (estimate, −0.32, 95 percent CI, −0.41 to −0.24; p<0.001) independent of pre- and post-treatment left ventricular ejection fraction, diabetes status, hypertension, tobacco use, age, BMI, haematocrit, receipt of potentially cardioprotective medications, and chemotherapy regimens.

Baseline adjusted changes in 6-minute walk distance, left ventricular ejection fraction, and left ventricular strain showed no association with 24-month post-breast cancer treatment fatigue levels.