A research team recently found an independent link between exercise intolerance and poorer neurocognitive outcomes in adult survivors of childhood acute lymphoblastic leukemia (ALL). Results were reported in Cancer.
This cross-sectional study included 341 adult survivors of childhood ALL from the St Jude Lifetime cohort study who were evaluated in comparison with a control population (288 participants) for exercise tolerance and neurocognitive function.
Exercise tolerance was estimated by measuring the relative peak volume of oxygen (rpkVO2), defined as the peak oxygen volume with a heart rate at 85% of the patient’s estimated maximum heart rate. The rpkVO2 values were converted to metabolic equivalents for multivariate analyses. Neurocognitive function was assessed through neuropsychologic testing and patient self-reports.
The mean age upon ALL diagnosis was 5.1 years (range, 0.6-18.8) among survivors. At evaluation, the mean age of survivors was 28.5 years (range, 18.4-44.6), and the mean age of the control population was 32.2 years (range, 18.3-44.8).
Survivors of ALL demonstrated a lower adjusted mean rpkVO2 (23.45 mL/kg/min) compared with the control population (33.03 ml/kg/min; P <.001). Survivors of ALL also showed significantly poorer scores across multiple neurocognitive tests compared with the control population.
Multivariate testing of survivors of ALL indicated that higher exercise tolerance was significantly associated with higher scores for several neurocognitive metrics, such as verbal fluency (P <.001), dominant motor speed (P =.001), and math academics (P =.001). For survivors of ALL, poorer scores for verbal ability and focused attention were also associated with lower median metabolic equivalent values (P =.03 for each).
The researchers noted that their findings were “consistent with previous studies reporting associations between exercise intolerance and cognitive decline in healthy older adults” and recommended a randomized, prospective analysis to determine the potential for neurocognitive benefits from strategies to improve exercise tolerance.
- Phillips NS, Howell CR, Lanctot JQ, et al. Physical fitness and neurocognitive outcomes in adult survivors of childhood acute lymphoblastic leukemia: A report from the St. Jude Lifetime cohort [published online October 21, 2019]. Cancer. doi:10.1002/cncr.32510