Movement efficiency in survivors of childhood acute lymphoblastic leukemia: a report from the St. Jude lifetime cohort study

Purpose Movement efficiency, a measure of neuromuscular biomechanics, may be modified by physical activity. We aimed to assess the risk of and risk factors for low movement efficiency in survivors of childhood acute lymphoblastic leukemia (ALL). Methods Participants underwent an assessment of activity energy expenditure (AEE) with actigraphy, and the gold standard doubly labeled water, where the differences between elimination rates of oxygen and hydrogen from body water are evaluated over a week. Movement efficiency was assessed using the raw residuals of a linear regression between AEEs from accelerometers and doubly labeled water. Elastic-net logistic regressions were used to identify demographic, treatment, and functional variables associated with movement efficiency. Results The study cohort included 256 non-cancer controls and 302 ALL survivors (48% female), categorized as efficient ( N = 24), normal ( N = 245), or inefficient ( N = 33) based on their movement efficiency. There was no difference in the odds for poor movement efficiency between survivors ( n = 33, 10.9%) compared to controls ( n = 23, 9.0%, odds ratio [OR]: 1.19, 95% confidence interval [CI]: 0.67, 2.10; p = 0.55). In survivors, neuropathy was associated with a higher risk of being inefficient compared to efficient (OR 4.30, 95% CI 1.03–17.96), while obesity (≥ 30 kg/m 2 ) had a protective association (OR 0.18, 95% CI 0.04–0.87). Conclusions Neuropathy was associated with a higher risk of poor movement efficiency in survivors of childhood ALL. Implications for cancer survivors These results further highlight impairments associated with treatment-induced neuropathy in survivors of childhood ALL.