Associations of Cancer-Related Fatigue with Autonomic and Sensorimotor Functions in Children Treated for Brain Tumors: an Observational Study

Abstract

INTRODUCTION. Chronic fatigue syndrome is a condition, characterized by a severe fatigue that lasts continuously for more than 6 months and has a significant negative impact on the psychophysiological functions. Cancer-related fatigue is identified as an important symptom associated with cancer, associated with autonomic dysfunction. AIM. To reveal objective autonomic and neurodynamic indicators of the severity of CRF in children suffered of neuro-oncological diseases. MATERIAL AND METHODS. Children (8-17 years old) who were under dynamic observation after neuro-oncological diseases for more than six months (n=67) performed maximal tapping tasks, auditory-motor synchronization, and filled out the questionnaire «The Turkish Scale for the Assessment of Fatigue in Pediatric Oncology Patients Aged 7-18». Physiological indices (heart rhythm, peripheral temperature, skin conductance, breathing amplitude and frequency) were recorded at rest and during sensorimotor task. RESULTS AND DISCUSSION. The subscale “Sleep-related fatigue” positively correlates with the average frequency of maximum tapping and with the degree of its slowdown towards the end, which also correlates with the total score of the questionnaire. Statistically significant correlations of scores on the subscale “Subjective feelings of fatigue” with LF/HF and pNN50 at rest were revealed. The amplitude of thoracic respiration positively correlates with the scores of “Fatigue associated with daily activities”, “Subjective feeling of fatigue”, and the total score. Comparison of groups with a low and high total score of the questionnaire does not reveal statistically significant differences in the background indicators of heart rate variability, however, in the process of maximum tapping, the RMSSD and pNN50 indicators are higher, and the indicator of nonlinear heart rate analysis SD2/SD1 is lower in the group with low scores on the questionnaire. CONCLUSION. Children with cancer-related fatigue had reduced heart rate variability, lower parasympathetic tone and greater exhaustion during the tapping test. The combination of objective and subjective indicators reflects the dynamics of cancer-related fatigue and the rehabilitation process more reliably