Breath isoprene – aspects of normal physiology related to age, gender and cholesterol profile as determined in a proton transfer reaction mass spectrometry study

• Published in: Clinical chemistry and laboratory medicine Vol. 46; no. 7; pp. 1011 - 1018
• Main Authors: Kushch, Ievgeniia, Arendacká, Barbora, Štolc, Svorad, Mochalski, Pawel, Filipiak, Wojciech, Schwarz, Konrad, Schwentner, Lukas, Schmid, Alex, Dzien, Alexander, Lechleitner, Monika, Witkovský, Viktor, Miekisch, Wolfram, Schubert, Jochen, Unterkofler, Karl, Amann, Anton
• Format: Journal Article
• Language: English
• Published: Berlin Walter de Gruyter 2008; New York, NY
• Subjects: age; Aging; Biological and medical sciences; Body Mass Index; breath analysis; Breath Tests; Butadienes - analysis; Calibration; Cholesterol - blood; Exhalation; Female; gender; General aspects; Hemiterpenes - analysis; Humans; Investigative techniques, diagnostic techniques (general aspects); isoprene; Male; Mass Spectrometry; Medical sciences; Pentanes - analysis; proton transfer reaction-mass spectrometry (PTR-MS); serum total cholesterol; Sex Characteristics; Expired air; breath analysis; gender; isoprene; Sex; Lipids; Normal; serum total cholesterol; Cholesterol; Medicine; Body mass index; Clinical biology; Proton; Transfer; proton transfer reaction-mass spectrometry (PTR-MS); Serum; Physiology; Respiration; Mass spectrometry; Age
• ISSN: 1434-6621; 1437-4331
• DOI: 10.1515/CCLM.2008.181

Background: This study was performed to clarify variations in breath isoprene concentrations with age, gender, body mass index (BMI) and total serum cholesterol. Our cohort consisted of 205 adult volunteers of different smoking background without health complaints. Total cholesterol in blood serum was measured in 79 of these volunteers. Methods: Mixed expiratory exhaled breath was sampled using Tedlar bags. Concentrations of isoprene were then determined using proton transfer reaction-mass spectrometry. Results: Isoprene concentrations ranged from 5.8 to 274.9 ppb, with an overall geometric mean (GM) of 99.3 ppb. There was no statistically significant difference in mean isoprene in breath between males and females (GM 105.4 and 95.5 ppb, respectively). Ageing led to a decrease in concentration in men, with an estimated slope of the regression line for log-transformed isoprene concentrations of –0.0049, but did not influence isoprene levels in women. We did not observe any significant correlation between isoprene breath content and cholesterol level in blood, even after adjusting for the possible influence of age. Similarly, no correlation was found between isoprene levels and BMI. Conclusions: Isoprene concentrations in exhaled breath showed gender-specific correlations with respect to age. Further investigations are necessary to clarify the relation between isoprene concentrations in exhaled breath and cholesterol levels and synthesis rates in blood. Clin Chem Lab Med 2008;46:1011–8.