Breath isoprene--aspects of normal physiology related to age, gender and cholesterol profile as determined in a proton transfer reaction mass spectrometry study.
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.
Kushch
Ievgeniia
I
Department of Anaesthesiology and Critical Care Medicine, Innsbruck Medical University, Innsbruck, Austria.
Arendacká
Barbora
B
Stolc
Svorad
S
Mochalski
Pawel
P
Filipiak
Wojciech
W
Schwarz
Konrad
K
Schwentner
Lukas
L
Schmid
Alex
A
Dzien
Alexander
A
Lechleitner
Monika
M
Witkovský
Viktor
V
Miekisch
Wolfram
W
Schubert
Jochen
J
Unterkofler
Karl
K
Amann
Anton
A
D000375:Aging; D015992:Body Mass Index; D001944:Breath Tests; D002070:Butadienes / Q000032:analysis*; D002138:Calibration; D002784:Cholesterol / Q000097:blood*; D045853:Exhalation; D005260:Female; D045782:Hemiterpenes / Q000032:analysis*; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D010420:Pentanes / Q000032:analysis*; D012727:Sex Characteristics
D002070:Butadienes; D045782:Hemiterpenes; D010420:Pentanes; C005059:isoprene; D002784:Cholesterol