Physical activity level is not a determinant of autonomic nervous system activity and clinical severity in children/adolescents with sickle cell anemia: A pilot study

Background Autonomic nervous system (ANS) activity has been suggested to modulate the clinical severity of sickle cell anemia (SCA) by increasing the risk for vaso‐occlusive events. Regular physical activity (PA) is known to improve ANS activity and health status in several cardiovascular and metabolic diseases. Whether regular PA improves the health status of SCA patients remains unknown. Procedure Twenty‐two patients with SCA and 15 healthy (AA) children/adolescents participated to the study. Heart rate variability was measured in supine position and after a tilt‐test to quantify the ANS activity. PA energy expenditure (PAEE) was assessed with questionnaire. Results 1) PAEE was lower in SCA compared to AA (190 ± 152 vs. 432 ± 277 kcal·d−1, respectively, P