This article is more than 5 years old. Information may no longer be current.
Increased cranial radiation linked to cognitive impairment in childhood ALL survivors
Click Here to Manage Email Alerts
Adult survivors of acute lymphoblastic leukemia who underwent treatment with 24 Gy of cranial radiation therapy were at increased risk for cognitive impairment, according to study results.
The analysis included 127 survivors who had been treated with 18 Gy and 138 survivors who had received 24 Gy.
Gregory T. Armstrong, MD, MSCE, of the department of epidemiology and cancer control at St. Jude Children’s Research Hospital, and colleagues measured cognitive impairment on the Wechsler Memory Scale–Fourth Edition (WMS-IV).
Gregory T. Armstrong
A subcohort of 85 survivors completed structural and functional neuroimaging.
Survivors who underwent treatment with 24 Gy experienced immediate memory impairment at a rate of 33.8% (95% CI, 25.9-42.4) and delayed memory impairment at a rate of 30.2% (95% CI, 22.6-38.6). Survivors who underwent treatment with 18Gy did not experience impairment in immediate or delayed memory, researchers wrote.
Survivors in the 24-Gy group had mean scores for long-term narrative memory that were equal to those for individuals aged at least 69 years, study results showed.
Researchers observed a link between impaired immediate memory and both smaller right (P=.02) and left (P=.008) temporal lobe volumes. Thinner parietal and frontal cortices yielded more impairment in delayed memory.
Memory impairment was accompanied by lower hippocampal volumes and increased functional MRI activation, researchers said.
Analysis of results from the Brief Cognitive Status Exam from the WMS-IV indicated that 24-Gy exposure was associated with reduced cognitive status (18.5%; 95% CI, 12.4-26.1). Those who received 18 Gy did not experience this reduced cognitive status (8.7%; 95% CI, 4.4-15). This may suggest a dose–response effect, according to researchers.
“Continued follow-up of this population is needed to determine their true risk for memory impairment as they age,” Armstrong and colleagues wrote. “Future studies should determine the longitudinal trajectory of memory loss and monitor for frank dementia as this population ages, and if longitudinal memory loss is confirmed, intervention strategies to slow that loss — such as physical activity interventions — should be considered.”
Click Here to Manage Email Alerts