Genetic Variation in MAP3K1 Associates with Ventilator-Free Days in Acute Respiratory Distress Syndrome.

Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) regulates numerous intracellular signaling pathways involved in inflammation and apoptosis. We hypothesized that genetic variation in MAP3K1 might be associated with outcomes in patients with acute respiratory distress syndrome (ARDS), and that these variants would alter MAP3K1-mediated changes in inflammation and transcriptional regulation. To test this hypothesis, we genotyped single-nucleotide polymorphisms covering linkage disequilibrium bins in MAP3K1 in 306 subjects with ARDS from the ARDSNet FACTT (Fluid and Catheter Treatment Trial) study, and tested for associations between MAP3K1 single-nucleotide polymorphisms and ventilator-free days (VFDs) and mortality. We then validated these associations in a separate cohort of 241 patients with ARDS from Harborview Medical Center (Seattle, WA). We found the variant allele of rs832582 (MAP3K1906Val) was significantly associated with decreased VFDs using multivariate linear regression (-6.1 d, false discovery rate = 0.06) in the FACTT cohort. In the Harborview Medical Center cohort, subjects homozygous for MAP3K1906Val also had decreased VFDs (-15.1 d, false discovery rate < 0.01), and increased 28-day mortality (all subjects homozygous for the rare allele died). In whole blood stimulated with various innate immune agonists ex vivo, MAP3K1906Val was associated with increased IL-1ß, IL-6, IL-8, monocyte chemoattractant protein 1, and TNF-α production. Transcriptome analysis of whole blood stimulated with Toll-like receptor 4 agonist ex vivo demonstrated enrichment of inflammatory gene sets in subjects homozygous for MAP3K1906Val. Our findings show a robust association between the variant allele of rs832582 (MAP3K1906Val) and decreased VFDs in patients with ARDS and suggest that this variant may predispose individuals to a greater inflammatory response.

Associations between single nucleotide polymorphisms in the FAS pathway and acute kidney injury.

INTRODUCTION: To determine whether single nucleotide polymorphisms (SNPs) in FAS and related genes are associated with acute kidney injury (AKI) in patients with acute respiratory distress syndrome (ARDS). METHODS: We studied 401 (Caucasian N = 310 and African-American N = 91) patients aged ≥ 13 years with ALI who enrolled in the Fluid and Catheter Treatment Trial (FACTT) between 2000 and 2005 from 20 North American centers. We genotyped 367 SNPs in 45 genes of the Fas/Fas ligand pathway to identify associations between SNPs in Fas pathway genes and the development of AKI by day 2 after enrollment in FACTT, adapting Acute Kidney Injury Network (AKIN) criteria. Written informed consent was obtained from participants or legally authorized surrogates in the original FACTT study and available to use for secondary analysis. RESULTS: In Caucasian patients, we identified associations between two SNPs and the incidence of AKI (stage 1 and above): rs1050851 and rs2233417; both are found within the gene for nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (NFKBIA). For rs1050851 and rs2233417, the odds ratios (ORs) were 2.34 (95 % confidence interval (CI) = 1.58-3.46, p = 1.06 × 10(-5), FDR = 0.003) and 2.46 (CI = 1.61-3.76, p = 1.81 × 10(-5), FDR = 0.003) for each minor allele, respectively. The associations were stronger still for AKIN stage 2-3 with respective ORs 4.00 (CI = 2.10-7.62, p = 1.05 × 10(-5), FDR = 0.003) and 4.03 (CI = 2.09-7.77, p = 1.88 × 10(-5), FDR = 0.003) for each minor allele homozygote. We observed no significant association between these SNPs and AKI in the smaller subset of African Americans. CONCLUSION: In Caucasian patients with ALI, the presence of minor alleles in two SNPs in NFKBIA was strongly associated with the development of AKI. TRIAL REGISTRATION: NCT00281268 . Registered 20/01/2006.

Genetic variation in the FAS gene and associations with acute lung injury.

RATIONALE: Fas (CD95) modulates apoptosis and inflammation and is believed to play an important role in lung injury. OBJECTIVES: To determine if common genetic variation in FAS is associated with acute lung injury (ALI) susceptibility, risk of death, and FAS gene expression. METHODS: We genotyped 14 single nucleotide polymorphisms (tagSNPS) in FAS in samples from healthy white volunteers (control subjects, n = 294) and patients with ALI (cases, n = 324) from the ARDSnet Fluid and Catheter Treatment Trial (FACTT). FAS genotypes associated with ALI in the discovery study were confirmed in a nested case-control validation study of critically ill patients at risk for ALI (n = 657). We also tested for associations between selected tagSNPS and FAS mRNA levels in whole blood from healthy control subjects exposed to media alone or LPS ex vivo. MEASUREMENTS AND MAIN RESULTS: We identified associations between four tagSNPs in FAS (FAS(-11341A>T) [rs17447140], FAS(9325G>A) [rs2147420], FAS(21541C>T) [rs2234978], and FAS(24484A>T) [rs1051070]) and ALI case status. Haplotype-based analyses suggested that three of the tagSNPs (FAS(9325G>A), FAS(21541C>T), and FAS(24484A>T)) function as a unit. The association with this haplotype and ALI was validated in a nested case-control study of at-risk subjects (P = 0.05). This haplotype was also associated with increased FAS mRNA levels in response to LPS stimulation. There was no association between FAS polymorphisms and risk of death among ALI cases. CONCLUSIONS: Common genetic variants in FAS are associated with ALI susceptibility. This is the first genetic evidence supporting a role for FAS in ALI.

Using the medical record to evaluate the quality of end-of-life care in the intensive care unit.

RATIONALE: We investigated whether proposed "quality markers" within the medical record are associated with family assessment of the quality of dying and death in the intensive care unit (ICU). OBJECTIVE: To identify chart-based markers that could be used as measures for improving the quality of end-of-life care. DESIGN: A multicenter study conducting standardized chart abstraction and surveying families of patients who died in the ICU or within 24 hrs of being transferred from an ICU. SETTING: ICUs at ten hospitals in the northwest United States. PATIENTS: Overall, 356 patients who died in the ICU or within 24 hrs of transfer from an ICU. MEASUREMENTS: The 22-item family assessed Quality of Dying and Death (QODD-22) questionnaire and a single item rating of the overall quality of dying and death (QODD-1). ANALYSIS: The associations of chart-based quality markers with QODD scores were tested using Mann-Whitney U tests, Kruskal-Wallis tests, or Spearman's rank-correlation coefficients as appropriate. RESULTS: Higher QODD-22 scores were associated with documentation of a living will (p = .03), absence of cardiopulmonary resuscitation performed in the last hour of life (p = .01), withdrawal of tube feeding (p = .04), family presence at time of death (p = .02), and discussion of the patient's wish to withdraw life support during a family conference (p < .001). Additional correlates with a higher QODD-1 score included use of standardized comfort care orders and occurrence of a family conference (p < or = .05). CONCLUSIONS: We identified chart-based variables associated with higher QODD scores. These QODD scores could serve as targets for measuring and improving the quality of end-of-life care in the ICU.

Inflammation and immune-related candidate gene associations with acute lung injury susceptibility and severity: a validation study.

INTRODUCTION: Common variants in genes related to inflammation, innate immunity, epithelial cell function, and angiogenesis have been reported to be associated with risks for Acute Lung Injury (ALI) and related outcomes. We tested whether previously-reported associations can be validated in an independent cohort at risk for ALI. METHODS: We identified 37 genetic variants in 27 genes previously associated with ALI and related outcomes. We prepared allelic discrimination assays for 12 SNPs from 11 genes with MAF>0.05 and genotyped these SNPs in Caucasian subjects from a cohort of critically ill patients meeting criteria for the systemic inflammatory response syndrome (SIRS) followed for development of ALI, duration of mechanical ventilation, and in-hospital death. We tested for associations using additive and recessive genetic models. RESULTS: Among Caucasian subjects with SIRS (n = 750), we identified a nominal association between rs2069832 in IL6 and ALI susceptibility (OR(adj) 1.61; 95% confidence interval [CI], 1.04-2.48, P = 0.03). In a sensitivity analysis limiting ALI cases to those who qualified for the Acute Respiratory Distress Syndrome (ARDS), rs61330082 in NAMPT was nominally associated with risk for ARDS. In terms of ALI outcomes, SNPs in MBL2 (rs1800450) and IL8 (rs4073) were nominally associated with fewer ventilator-free days (VFDs), and SNPs in NFE2L2 (rs6721961) and NAMPT (rs61330082) were nominally associated with 28-day mortality. The directions of effect for these nominal associations were in the same direction as previously reported but none of the associations survived correction for multiple hypothesis testing. CONCLUSION: Although our primary analyses failed to statistically validate prior associations, our results provide some support for associations between SNPs in IL6 and NAMPT and risk for development of lung injury and for SNPs in IL8, MBL2, NFE2L2 and NAMPT with severity in ALI outcomes. These associations provide further evidence that genetic factors in genes related to immunity and inflammation contribute to ALI pathogenesis.