ESPE Yearbook of Paediatric Endocrinology

To read the full abstract: J Clin Med. 2020 Feb 19;9(2). pii: E562. e_rochette@chu-clermontferrand.fr

This 5-month prospective case-control study was designed to evaluate the impairment of metabolic response to exercise in 20 childhood acute leukaemia survivors (CALSs), by the analysis of substrate oxidation during submaximal exercise, in comparison with 20 matched healthy controls.

The different signs of metabolic syndrome are frequently observed in CALSs, due not only to previous treatments, but also to lifestyle changes (reduced physical activity, increased fatigue, reduced energy expenditure). Metabolic fitness can be estimated by indirect calorimetry, measuring the ability to oxidize lipids and carbohydrates during incremental exercise; this reflects the physiological status of the muscles.

This study shows that CALSs have reduced carbohydrate and fat oxidation rates, compared to healthy controls. They also show lower relative and absolute VO2 peak, which is an indicator of impaired cardiorespiratory fitness associated with higher fatigability during physical exercise. The authors speculated that these findings were mainly related to the effect of anthracyclines on cardiac function (despite a normal echocardiography at rest). Damage of the pulmonary, musculoskeletal and neuronal adaptative mechanisms that regulate the physiological response to exercise, as adverse effects of different chemotherapeutic agents, may be associated. Specifically, the impaired muscle function may be related to the catabolic effects of treatments, such as vincristine and corticosteroids, which cause limitation of the ability of muscle fibers to consume oxygen. This already damaged oxidative system could be further affected by a low level of physical activity and sedentary lifestyle habits, causing impairment of metabolic fitness.

Reference:

1. Myrdal OH, Kanellopoulos A, Christensen JR, Ruud E, Edvardsen E, Kongerud J, Sikkeland LI;Lund MB. Risk factors for impaired pulmonary function and cardiorespiratory fitness in very long-term adult survivors of childhood acute lymphoblastic leukaemia after treatment with chemotherapy only. Acta Oncol. 2018;57:658–64.