Exhaled Breath Condensate Nitrate Levels are Inversely Associated with the Body Mass Index of Patients without Respiratory DiseaseAna Fernandez-Bustamante1,2*, Tamas Seres1, Amanda Agazio1,2, Alexander T. Pennington1,3, Uwe Christians1,3, Jelena Klawitter1,3 and John E. Repine2,4
- *Corresponding Author:
- Ana Fernandez-Bustamante
MD, PhD, Department of Anesthesiology and
Webb-Waring Center, University of Colorado
SOM 12631 E 17th Ave AO-1, R2012
MS 8202 Aurora, CO, 80045, USA
Tel: +001-303-724- 2935
E-mail: [email protected]
Received date: November 01, 2014; Accepted date: February 24, 2015; Published February 28, 2015
Citation: Fernandez-Bustamante A, Seres T, Agazio A, Pennington AT, Christians U, et al. (2015) Exhaled Breath Condensate Nitrate Levels are Inversely Associated with the Body Mass Index of Patients without Respiratory Disease. J Pulm Respir Med 5:243. doi:10.4172/2161-105X.1000243
Copyright: © 2015 Fernandez-Bustamante A, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Background: Repeated observations suggest that the incidence and/or severity of the Acute Respiratory Distress Syndrome (ARDS) is lower in mildly obese humans compared to lean subjects, phenomenon called the Obesity-ARDS Paradox. A reduced lung nitrosative stress could contribute to this unexplained protection. We measured levels of nitrate, the most oxidized nitric oxide (NO) metabolite, and other related metabolites in the exhaled breath condensate (EBC) of obese (composed of both overweight or mildly obese) and normal weight patients.
Methods: We studied patients without respiratory disease immediately after starting mechanical ventilation for elective surgery. We performed targeted metabolomics analyses of EBC and blood samples. We measured concentrations of arginine, asymmetrical dimethylarginine (ADMA), symmetrical dimethylarginine (SDMA), nitrite, and nitrate and then analyzed their relationship to body mass index (BMI). We compared patients classified as BMI<25 (normal) or 25-34.9 (obese).
Results: 21 patients were included in the analysis: 5 with a BMI<25 and 16 with a BMI 25-34.9. Concentrations of nitrate in EBC, but not in plasma, inversely correlated with BMI. EBC nitrate levels positively correlated with EBC nitrite but not with plasma nitrate levels. EBC nitrite levels inversely correlated with plasma nitrite levels. Patients with a BMI 25-34.9 had significantly lower EBC nitrate levels than patients with a BMI<25.
Conclusion: Our results suggest a lower nitrosative stress in the lungs of overweight and mildly obese patients compared to normal weight patients. This observation deserves further evaluation as a possible contributing factor to the Obesity ARDS Paradox.