Department of Medicine, University of Virginia, Charlottesville, Virginia, United States of America.
PLoS One. 2013 Apr 23;8(4):e61022. doi: 10.1371/journal.pone.0061022. Print 2013.
Obese children frequently complain of breathlessness. Asthma and obesity can both contribute to the symptoms during exercise, and this symptom can contribute to a diagnosis of asthma in these children. Despite the high prevalence of obesity few studies have investigated the cardiopulmonary physiology of breathlessness in obese children with a diagnosis of asthma.
In this case-control study, thirty adolescents between age 12 and 19 were studied with baseline spirometry and a cardiopulmonary exercise test. Ten adolescents were normal controls, ten had obesity without a diagnosis of asthma, and ten had obesity with a history of physician-diagnosed asthma.
Baseline characteristics including complete blood count and spirometry were comparable between obese adolescents with and without a diagnosis of asthma. During exercise, obese asthmatic and obese non-asthmatic adolescents had significantly reduced physical fitness compared to healthy controls as evidenced by decreased peak oxygen uptake after adjusting for actual body weight (21.7 ± 4.5 vs. 21.4 ± 5.4 vs. 35.3 ± 5.8 ml/kg/min, respectively). However, pulmonary capacity at the peak of exercise was comparable among all three groups as evidenced by similar pulmonary reserve.
In this study, breathlessness was primarily due to cardiopulmonary deconditioning in the majority of obese adolescents with or without a diagnosis of asthma.
肥胖儿童经常抱怨呼吸困难。哮喘和肥胖都可能导致运动期间出现症状，而且这种症状可能导致这些儿童被诊断为哮喘。尽管肥胖的患病率很高，但很少有研究调查过诊断为哮喘的肥胖儿童呼吸困难的心肺生理学。
在这项病例对照研究中，对 30 名年龄在 12 至 19 岁之间的青少年进行了基线肺功能检查和心肺运动测试。10 名青少年为正常对照，10 名肥胖但无哮喘诊断，10 名肥胖且有医生诊断的哮喘病史。
肥胖青少年有哮喘和无哮喘的两组间的基线特征，包括全血细胞计数和肺功能检查，均相似。在运动过程中，肥胖哮喘和肥胖非哮喘青少年的身体素质明显低于健康对照组，这表现为调整实际体重后的峰值摄氧量下降（分别为 21.7 ± 4.5、21.4 ± 5.4 和 35.3 ± 5.8 ml/kg/min）。然而，三组的运动峰值时的肺容量相当，表明肺储备相似。
在这项研究中，呼吸困难主要是由于大多数肥胖青少年有或没有哮喘诊断的心肺功能失调引起的。
