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Aerobic capacity in late adolescents infected with HIV and controls
W Todd Cade1, Ligia Peralta, Randall E Keyser
1University of Maryland School of Medicine, 100 Penn Street AHB 115, Baltimore, MD 21201-1082, USA. tcade@som.umaryland.edu
Objectives:
The objective of this study was to determine if aerobic capacity was diminished in late adolescents infected with HIV compared to controls matched for age, gender, and physical activity level.
Study Design:
This study was a quasi-experimental cross sectional analysis. Subjects (11 female, four male) were 15 late adolescents with HIV (18 +/- 0.03 years) (CD4: 499.2 +/- 37.5 cells/mm(3), viral load: 22043 +/- 9976.6 copies/ml, haematocrit: 36.4 +/- 1.2) and 15 age, gender, and activity level matched controls (18 +/- 0.03) who underwent maximal treadmill exercise testing, while oxygen consumption, carbon dioxide production, ventilation, and ECG data were simultaneously recorded via open circuit spirometry and electrocardiography.
Results:
Peak oxygen consumption (p < 0.003), peak treadmill stage (p < 0.003), treadmill duration (p < 0.004), and oxygen pulse (p < 0.009) were lower in those infected with HIV compared to controls. Functional aerobic impairment was observed in the late adolescents infected with HIV, pointing toward pathological limitations of the oxidative metabolic pathway.
Conclusion:
This study has demonstrated that aerobic capacity was reduced substantially in late adolescents infected with HIV, below that observed in controls. The findings suggest that this decrease in oxidative capacity was due to mechanisms other than physiologic deconditioning.
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