Tamoxifen tied to cognitive drop in breast cancer patients

NEW YORK (Reuters Health) - Tamoxifen is associated with impaired cognitive function in postmenopausal women, Dutch researchers reported online February 8th in the Journal of Clinical Oncology.

"Our results are important because many breast cancer patients are eligible for endocrine therapy and intact cognitive functioning is an important precondition for well being," lead author Christina M. Schilder told Reuters Health by email.

Schilder, from the Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital in Amsterdam, and her colleagues studied 80 women who received adjuvant endocrine therapy with tamoxifen, 99 who received exemestane, and 120 healthy controls. None of the cancer patients received chemotherapy.

After 1 year of treatment, the exemestane group performed no worse than controls on any cognitive domain of neuropsychological assessments.

The tamoxifen users, however, had significantly poorer verbal memory and executive functioning compared to controls, and significantly slower information processing speed compared to exemestane users.

There were no significant differences between groups in visual memory, working memory, verbal fluency, reaction speed, and motor speed.

"It is important to further study the impact of endocrine treatments on cognitive functioning because there are still many questions unanswered," Schilder said. "For example, we only evaluated cognitive functioning after one year of treatment, but breast cancer patients usually take endocrine agents for 5 or even more years. Furthermore, it is unknown whether the cognitive effects of endocrine treatment are lasting after the treatment is finished."

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