“Chemo Brain” May Be Present Before Chemotherapy
Chemotherapy may not necessarily be the reason that patients with breast cancer often complain of “fuzzy thinking” and difficulty solving problems, according to research showing that cognitive changes are present in some patients at baseline, and may be related to fatigue and anxiety.
Bernadine Cimprich, PhD, RN, Professor Emeritus at the University of Michigan School of Nursing in Ann Arbor, said that altered neural activation before treatment, along with fatigue, contributed to cognitive problems in women who were diagnosed with breast cancer before they received chemotherapy, based on a study that included 65 women with stage 0 through stage IIa breast cancer.
Of these women, 28 were slated for adjuvant chemotherapy and 37 for radiation alone. These patients were age-matched to 32 healthy controls.
The investigators used functional magnetic resonance imaging (fMRI) to assess changes in the left inferior frontal gyrus of the brain during tasks associated with working memory. The women had undergone fMRI scans before adjuvant therapy and 1 month after therapy. Healthy controls had fMRI scans performed after a negative mammogram and again 5 months later.
Patients who received chemotherapy reported significantly greater fatigue than those undergoing radiation or healthy controls. They also performed more poorly on the verbal memory tasks before treatment, which corresponded to reduced brain activity on fMRI. Healthy controls had more activation in the left inferior frontal gyrus, and the radiotherapy group fell in between these 2 groups on fMRI. The level of fatigue was correlated with performance on the memory task.
C. Kent Osborne, MD, Director, Breast Cancer Center, and Professor of Medicine and Cellular and Structural Biology, Baylor College of Medicine, Houston, TX, who moderated the press conference where these findings were presented, said that these findings make sense.
Worry and stress associated with a breast cancer diagnosis, along with anticipatory anxiety before chemotherapy, can affect cognitive function, Dr Osborne agreed, calling for more attention to this problem. “Cognitive effects can worsen over time,” Dr Osborne added.