Morean, D.F., O'Dwyer, L., & Cherney, L.R. (2015). Therapies for cognitive deficits associated with chemotherapy for breast cancer: A systematic review of objective outcomes. Archives of Physical Medicine and Rehabilitation, 96, 1880–1897.
PHASE OF CARE: Late effects and survivorship
Studies of pharmacologic interventions were not found to be effective in improving cognitive function. Medications reviewed included d-methylphenidate (n = 1), epoetin alfa (n = 2), and ginkgo biloba (n = 1). Evidence for nonpharmacologic interventions was mixed. No improvements in cognitive function were found with Tibetan sound meditation (n = 1). Natural restorative therapy (n = 1) improved attention only when comparing the baseline with the final 90-day evaluation (p = 0.01). Exercise (n = 1) improved attention (p = 0.019) and verbal memory (p = 0.048) but not working memory. Cognitive rehabilitation (n = 1) improved four out of six measures of information processing speed (p < 0.05) but not attention, verbal memory, or executive function. Cognitive behavioral training (n = 2) improved verbal memory (p < 0.05) in both studies and was effective in improving in information processing speed when compared to baseline scores in one study (p ≤ 0.01) but not the other. Computerized cognitive training was effective in one study in improving processing speed (p = 0.009), executive function (p = 0.008), and a measure of executive function and language (p = 0.003) but not verbal memory. However, in another study, there was no difference in verbal memory or information processing speed between the intervention and control groups.
Nonpharmacologic interventions, especially cognitive training, may have a role for improving attention, information processing speed, and verbal memory. Exercise and computerized cognitive training may be effective for improving executive function. However, additional research validating these findings with larger sample sizes and evaluating other cognitive domains is needed. In addition, studies determining the dose or duration of interventions is required for a durable response.
These findings suggest that nonpharmacologic, not pharmacologic, interventions may be helpful in managing chemotherapy-induced cognitive impairment in patients with breast cancer. However, these findings were based on a small number of studies per intervention. Additional research validating which interventions might be useful in improving cognitive impairments in women receiving chemotherapy for breast cancer is needed.