Dysautonomia in Childhood Cancer Survivors: A Widely Underestimated Risk

Abstract

Purpose: Survival rate of childhood cancers is now reaching 80% overall. However, early or late complications related to surgery, chemotherapy, and radiotherapy remain at a high rate and greatly increase the risk of late mortality. The objective of this study is to assess the autonomic nervous system (ANS) activity, measured through heart rate variability indices in childhood cancer survivors compared with healthy controls.

Methods: This prospective study included 51 long-term childhood cancer survivors diagnosed before 15 years of age between 1987 and 1992 and controlled for age and sex with healthy volunteers.

Results: We observed a significant increase in spontaneous heart rate (beats per minute) (67 ± 10 vs. 60 ± 10, p = 0.001), and all the studied parameters showed a significantly altered ANS activity in cases compared with healthy controls. In both groups, the main cofactors of dysautonomia (tobacco, drugs, cannabis, estro-progestative pills, alcohol, limited physical activity) were analyzed without any significant difference. The effect of cancer treatments received was not analyzed due to the small number of participants.

Conclusion: The results showed a significant ANS dysfunction in childhood cancer survivors compared with healthy controls and suggested the value of autonomic screening to underscore and possibly quantify the effect of the cancer treatments in a larger cohort. This evaluation could lead to the recommendation to increase physical activity, the most efficient way known to improve ANS activity, as already shown in other pathologies (breast cancer).

Keywords: autonomic nervous system; childhood cancer survivors; dysautonomia; long-term follow-up.