Study Examines Factors Contributing to "Chemobrain" in Patients With Breast Cancer

Women with breast cancer — as well as the health care professionals who treat them – often wonder about the origin of their cancer-related cognitive impairment (CRCI), often referred to as “chemobrain.” This side effect can include difficulties with memory, attention and information processing.

The causes of CRCI are varied and complex, and medical, psychological and demographic factors can play a role. To shed more light on subject, researchers at the University of Rochester Medical Center’s Wilmot Cancer Institute embarked on the largest study to date, with a focus on when and why the condition occurs, who is most likely to develop it, and whether age, education, race and menopausal status, among other factors, have an effect.

Their findings: the condition known as “chemobrain” is a pervasive — and persistent — problem in women with breast cancer.

Michelle C. Janelsins, Ph.D., an assistant professor of Surgery in Wilmot’s Cancer Control and Survivorship program, looked at the cognitive difficulties of 581 patients with breast cancer recruited from community oncology clinics across the United States. Results were compared to those of a control group of 364 healthy individuals, some of whom were friends or family of patients or unrelated. The groups were balanced in age, ethnicity and marital status.

Both groups were assessed using the FACT-Cog tool, which examines perceived cognitive impairment, cognitive abilities, impact of cognitive impairment on quality of life and cognitive impairment as perceived by others. In addition to separate scores for each category, investigators generated an overall cognitive function score. Researchers conducted the FACT-Cog at three different points: seven days before chemotherapy, within four weeks of chemotherapy completion and six months after the second assessment.

In addition to the FACT-Cog, researchers also assessed participants’ reading ability and depressive symptoms, the latter, with an item from the Multidimensional Fatigue Symptom Inventory where participants responded to the statement “I feel depressed” using a scale ranging from “not at all” to “very much.”

Before chemotherapy began, patients with breast cancer had lower FACT-Cog scores than their healthy counterparts. Investigators found that when compared with participants who did not have cancer, FACT-Cog scores of women with breast cancer exhibited 45 percent more impairment. In fact, over the period of nearly one year from diagnosis and prechemotherapy to the postchemotherapy follow-up at six months) 36.5 percent of women reported a decline in scores compared with 13.6 percent of the healthy women, according to the study.

“Our study suggests that perceived CRCI is a complex, multifactorial problem for patients with breast cancer and that it is likely that a combination of demographic, medical and psychological factors plays a role in predisposing someone to CRCI,” study authors wrote.

“Before any chemotherapy, patients reported lower FACT-Cog scores than did controls; however, we found this effect was influenced by age, race, cognitive reserve, and higher anxiety and depressive symptoms, as our results became a trend after including these covariates.”

Overall, the study found that predictors of perceived cognitive impairment included:

• Increased baseline levels of anxiety and depressive symptoms,
• Lower baseline cognitive reserve
• Perimenopausal or postmenopausal status
• Younger age and black race

Additionally, women who underwent hormone therapy and/or radiation treatment following chemotherapy had similar cognitive problems as women who solely received chemotherapy.

“Our study, from one of the largest nationwide studies to date, shows that cancer-related cognitive problems are a substantial and pervasive issue for many women with breast cancer,” explained Janelsins, in a statement.

“We are currently assessing these data in the context of objective cognitive measures and to understand the role of possible biologic mechanisms that may confer risk to cognitive problems in patients."