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Published in: Respiratory Research 1/2018

Open Access 01-12-2018 | Research

Associations of the plasma lipidome with mortality in the acute respiratory distress syndrome: a longitudinal cohort study

Authors: Michael D. Maile, Theodore J. Standiford, Milo C. Engoren, Kathleen A. Stringer, Elizabeth S. Jewell, Thekkelnaycke M. Rajendiran, Tanu Soni, Charles F. Burant

Published in: Respiratory Research | Issue 1/2018

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Abstract

Background

It is unknown if the plasma lipidome is a useful tool for improving our understanding of the acute respiratory distress syndrome (ARDS). Therefore, we measured the plasma lipidome of individuals with ARDS at two time-points to determine if changes in the plasma lipidome distinguished survivors from non-survivors. We hypothesized that both the absolute concentration and change in concentration over time of plasma lipids are associated with 28-day mortality in this population.

Methods

Samples for this longitudinal observational cohort study were collected at multiple tertiary-care academic medical centers as part of a previous multicenter clinical trial. A mass spectrometry shot-gun lipidomic assay was used to quantify the lipidome in plasma samples from 30 individuals. Samples from two different days were analyzed for each subject. After removing lipids with a coefficient of variation > 30%, differences between cohorts were identified using repeated measures analysis of variance. The false discovery rate was used to adjust for multiple comparisons. Relationships between significant compounds were explored using hierarchical clustering of the Pearson correlation coefficients and the magnitude of these relationships was described using receiver operating characteristic curves.

Results

The mass spectrometry assay reliably measured 359 lipids. After adjusting for multiple comparisons, 90 compounds differed between survivors and non-survivors. Survivors had higher levels for each of these lipids except for five membrane lipids. Glycerolipids, particularly those containing polyunsaturated fatty acid side-chains, represented many of the lipids with higher concentrations in survivors. The change in lipid concentration over time did not differ between survivors and non-survivors.

Conclusions

The concentration of multiple plasma lipids is associated with mortality in this group of critically ill patients with ARDS. Absolute lipid levels provided more information than the change in concentration over time. These findings support future research aimed at integrating lipidomics into critical care medicine.
Appendix
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Metadata
Title
Associations of the plasma lipidome with mortality in the acute respiratory distress syndrome: a longitudinal cohort study
Authors
Michael D. Maile
Theodore J. Standiford
Milo C. Engoren
Kathleen A. Stringer
Elizabeth S. Jewell
Thekkelnaycke M. Rajendiran
Tanu Soni
Charles F. Burant
Publication date
01-12-2018
Publisher
BioMed Central
Published in
Respiratory Research / Issue 1/2018
Electronic ISSN: 1465-993X
DOI
https://doi.org/10.1186/s12931-018-0758-3

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