Children with
acute lymphoblastic leukemia (ALL) often experience treatment-related neurocognitive deficits and significant
pain.
Pain may exacerbate these
cognitive impairments. This study examined
neuropathic pain and neurocognitive outcomes in survivors of
childhood ALL treated with contemporary
therapy on a clinical trial (NCT00137111). There were 345 survivors (45% female, M = 6.9 years at diagnosis) who completed neurocognitive assessments including measures of sustained attention, learning and memory, and parent ratings of attention during at least one of 4 time points: on-
therapy (Induction and Reinduction), end of
therapy, and 2 years post-
therapy. At-risk performance was defined as a score at least 1SD below the age-adjusted mean. Data on
neuropathic pain (events, duration, and severity according NCI Common Toxicity Criteria) and pharmacologic
pain management (
opioids and
gabapentin) were ascertained. Results showed that 135 survivors (39%) experienced
neuropathic pain during treatment. Compared with those without
pain, survivors with
pain had greater memory impairments at end of
therapy (California Verbal Learning Test [CVLT]-Total, 24% vs 12%, P = 0.046). Within the
pain group, survivors who experienced a greater number of
pain events (CVLT-Total = -0.88, P = 0.023) and those who were treated with
opioids (versus
gabapentin) had poorer learning and memory performance (CVLT-Total = -0.73, P = 0.011; Short Delay = -0.57, P = 0.024; Long Delay = -0.62, P = 0.012; and Learning Slope = -0.45, P = 0.042) across time points. These are considered medium-to-large effects (SD = 0.45-0.88).
Neuropathic pain may be a risk factor for learning problems after
therapy completion, and treatment for
pain with
opioids may also adversely affect neurocognitive performance. Therefore, patients who experience
pain may require closer monitoring and additional intervention for neurocognitive impairment.