"Chemo brain" can last up to five years

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"Chemo brain" is an accepted fact; that it could last longer than a year or so is not. So when patients of Karen Syrjala, co-director of the Survivorship Program at Fred Hutchinson, kept saying, "My brain is still not working right, things are not back to normal, what’s going on?" she crafted a study to find some answers.

Chemo brain is a common complaint among cancer patients, even long after treatment ends, as Syrjala knows only too well. “It’s very unsettling to people when they’re not as sharp as they’re accustomed to.” In an attempt to find answers and offer patients a road map of what to expect, she lead a study at the Fred Hutchinson Cancer Research Center of 92 chemo patients for five years, and discovered her patients' suspicions were correct: chemo often resulted in long-lasting cognitive impairment.

Although research has established mental problems for up to two years after treatment, there has been little research after that, making it difficult to distinguish from the effects of drugs or fatigue. “At one year there are still a lot of people on all kinds of different medications, which reduce memory and slow people down, and we really believed that once people got off all those medications, we would see a bump up,” says Syrjala. But to her surprise, they found that many symptoms lasted much longer, suggesting damage to DNA or cells themselves.

The study, published in the Journal of Clinical Oncology, used memory, word and dexterity tests to compare the memory and motor skills of the patients, who all had blood cancer, with a case-matched control group. In about 40 percent of survivors (versus 20 percent of the control group), mild verbal memory deficits and motor skill problems carried on to the five-year mark, suggesting they were permanent.

Syrjala points out that there are many tricks and techniques, like writing everything in a smartphone, that people can use to compensate for memory problems. And there was good news: While problems with information processing speed, multitasking and “wordfinding” — having a word on the tip of your tongue — were very common after chemo, most people made significant improvements by five years later.