Format

Send to

Choose Destination
Physiol Rep. 2015 Apr;3(4). pii: e12338. doi: 10.14814/phy2.12338.

Reduced fitness and abnormal cardiopulmonary responses to maximal exercise testing in children and young adults with sickle cell anemia.

Author information

1
Department of Pediatrics, Hematology, Oncology & Stem Cell Transplant, Ann & Robert H. Lurie Children's Hospital of Chicago Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA rliem@luriechildrens.org.
2
Department of Pediatrics, Hematology, Oncology & Stem Cell Transplant, Ann & Robert H. Lurie Children's Hospital of Chicago Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
3
Department of Pediatrics, Pulmonary Medicine Ann & Robert H. Lurie Children's Hospital of Chicago Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
4
Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL, USA.
5
Rodeghier Consultants, Chicago, Illinois, USA.

Erratum in

Abstract

Physiologic contributors to reduced exercise capacity in individuals with sickle cell anemia (SCA) are not well understood. The objective of this study was to characterize the cardiopulmonary response to maximal cardiopulmonary exercise testing (CPET) and determine factors associated with reduced exercise capacity among children and young adults with SCA. A cross-sectional cohort of 60 children and young adults (mean 15.1 ± 3.4 years) with hemoglobin SS or S/β(0) thalassemia and 30 matched controls (mean 14.6 ± 3.5 years) without SCA or sickle cell trait underwent maximal CPET by a graded, symptom-limited cycle ergometry protocol with breath-by-breath, gas exchange analysis. Compared to controls without SCA, subjects with SCA demonstrated significantly lower peak VO2 (26.9 ± 6.9 vs. 37.0 ± 9.2 mL/kg/min, P < 0.001). Subjects demonstrated slower oxygen uptake (ΔVO2/ΔWR, 9 ± 2 vs. 12 ± 2 mL/min/watt, P < 0.001) and lower oxygen pulse (ΔVO2/ΔHR, 12 ± 4 vs. 20 ± 7 mL/beat, P < 0.001) as well as reduced oxygen uptake efficiency (ΔVE/ΔVO2, 42 ± 8 vs. 32 ± 5, P < 0.001) and ventilation efficiency (ΔVE/ΔVCO2, 30.3 ± 3.7 vs. 27.3 ± 2.5, P < 0.001) during CPET. Peak VO2 remained significantly lower in subjects with SCA after adjusting for age, sex, body mass index (BMI), and hemoglobin, which were independent predictors of peak VO2 for subjects with SCA. In the largest study to date using maximal CPET in SCA, we demonstrate that children and young adults with SCA have reduced exercise capacity attributable to factors independent of anemia. Complex derangements in gas exchange and oxygen uptake during maximal exercise are common in this population.

KEYWORDS:

Cardiopulmonary fitness; exercise testing; sickle cell

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center