"Chemo brain" revisited
Memory and concentration problems in women who undergo chemotherapy for breast cancer is commonly referred to as "chemo brain". Most of what we know about it has come from anecdotal reports from patients and a few studies. Now, research has shed more light on the connection. Although investigations have generally been small and varied in design, all suggest that some women who undergo chemotherapy experience certain, often subtle, cognitive problems.
In a small study published in the journal Cancer (June 2004), researchers conducted neuropsychological tests of 18 women about to start chemotherapy for breast cancer (almost all had undergone surgery to remove the cancer). Initial testing included measures of intelligence, memory, and learning. Six women (33%) were found to have cognitive difficulties prior to chemotherapy. All of the subjects were tested again three months after completing chemotherapy, then nine months later. Eleven (61%) showed some level of cognitive decline three months post-chemotherapy. One year after completing chemotherapy, about half had improved; the others remained stable.
The study provides further evidence that chemotherapy can affect cognitive function. But it also suggests that cancer itself — or the distress related to diagnosis and initial treatment (surgery) — may also play a role in cognitive difficulties, which are further worsened by chemotherapy. The good news is that in many people, these brain changes fade after a year.
A different study, comparing breast cancer patients who received high-dose, standard-dose, or no chemotherapy, found that although cognitive problems remained after two years in some of the women (irrespective of dose level), after four years, there were no real differences among the groups.
In April 2005, British researchers published early results that compared cognitive functioning in 50 women who underwent chemotherapy to that of 43 healthy controls. Both groups were tested before the start of chemotherapy. Six months later, the treated group did significantly worse than the control group on tasks requiring a high degree of concentration and attention.
What to do about chemo brain
Currently, no treatments have been approved for chemo brain, though studies are under way. Research has shown that dexmethylphenidate (Focalin), a drug used to treat attention deficit hyperactivity disorder, increased alertness and improved memory in women who had undergone chemotherapy for breast or ovarian cancer.
For now, the best way to manage the effects of chemo brain is to employ some memory prompts. Make lists in a notebook or use "stickies" to keep track of tasks and events. Much more research is needed on chemo brain, so consider participating in a trial if you're offered the opportunity.
December 2005 Update404: