Having a bone marrow transplant, although it's the only way to cure some diseases, is distinctly unpleasant. Before such a transplant, patients undergo chemotherapy to kill off their diseased bone marrow. The process can kill off nerves as well; patients may lose motor skills and cognitive function. Researchers in Seattle looked at how patients fared as long as a year after their transplants.

What the researchers wanted to know: How does a bone marrow transplant affect neurocognitive function in the long term?

What they did: Researchers followed 142 adult patients at Fred Hutchinson Cancer Research Center from before their bone marrow transplants to a year after. (Actually, only about 85 percent of the patients received stem cells from bone marrow; the other 15 percent's came from other sources.) The patients had neuropsychological tests before their pretransplant chemotherapy or radiation therapy started, then about 80 days after the transplant, and again about a year after the transplant. The tests included IQ, motor skills, attention, and verbal skills. Only 54 patients actually made it to all three rounds of tests; 31 did not.

What they found: At 80 days, the average scores had declined on all tests. But after a year, those scores were back up to where they'd been before the transplants for almost all the tests. Motor dexterity and grip strength did not return to the level at which they'd been before the transplant. This counts only the nonrelapsed patients; 57 had relapsed or died within a year.

What the study means to you: While the harsh treatments certainly hurt cognitive function and motor skills in the short term, things get better. Patients who try to go back to work soon after their transplants may have trouble functioning—the researchers say patients should be encouraged to take on responsibilities gradually.

Caveats: Since the study excluded people who started pretransplant treatment as soon as they got to the cancer center and people who already had impairment of the central nervous system, it may not apply to the sickest people.

Find out more: www.lymphomation.org has information on stem cell transplants.

Read the article: Syrjala, K.L. et al. "Neuropsychologic Changes From Before Transplantation to 1 Year in Patients Receiving Myeloablative Allogeneic Hematopoietic Cell Transplant." Blood. Nov. 15, 2004, Vol. 104, No. 10, pp. 3386–3392.

Abstract online: http://www.bloodjournal.org