Neuropathy and neurocognitive impairment in long-term survivors of pediatric cancer treated without central nervous system (CNS) directed therapy.

Abstract

10020 Background: Survivors of pediatric cancer, including those without CNS-directed treatment, are at risk of neurocognitive impairment and peripheral or autonomic neuropathies; conditions that co-occur in non-cancer populations. Using the St. Jude Lifetime Cohort, we investigated associations between these sequelae to inform contributors to long-term cancer-related neurocognitive impairment. Methods: Clinically assessed survivors of pediatric cancer (N=2,138, mean age 31 [SD 13], 23[11] years from diagnosis, 51% male) not treated with CNS-directed therapy completed neurocognitive testing. Modified total neuropathy score peripheral sensory and motor subscales were combined with functional tasks and severity graded using a modified NCI CTCAE. Cardiac autonomic neuropathy was defined as impaired heart rate reserve (<80% age- sex-predicted or ≤62% with beta blocker). Separate log binomial regression models estimated risk of neurocognitive impairment (age adjusted z-score <10th percentile) associated with grade 2+ sensory, motor or autonomic neuropathy. Path analysis examined if pain with daily interference mediated associations between motor or sensory neuropathy and neurocognitive impairment. Results: 838 (39%) survivors had autonomic, 115 (5.4%) had motor and 162 (7.6%) had sensory neuropathy. Compared to those with no neuropathy, survivors with motor or sensory neuropathy had a higher risk of impairment in sustained attention, visual-motor processing speed, short- and long-term memory, and executive function (Table, p’s<0.01). Autonomic neuropathy was associated with a higher risk of impairment in visuo-motor processing speed (p=0.03). Pain partially mediated associations between sensory neuropathy and sustained attention (10% mediated, p=0.04), visual-motor processing speed (8% p=0.02), and executive function (14% p=0.02). Pain was not related to motor neuropathy. Conclusions: Peripheral and autonomic neuropathies are associated with significant risk of neurocognitive impairment in adult survivors of pediatric cancer. Research is needed to further understand shared mechanisms (e.g., pain, inflammation) to design targeted interventions to improve neuropathic symptoms and neurocognitive function. [Table: see text]