A genetic variant of hypoxia-inducible factor-1α is associated with adverse outcomes in acute kidney injury

Hypoxia-inducible factor-1 alpha (HIF-1 alpha) is a transcription factor that mediates many cellular responses to tissue hypoxia, a common feature of acute kidney injury (AKI). Here we studied 241 patients with AKI and determined the relationship to adverse outcome of a non-synonymous polymorphism in the coding region of the HIF-1 alpha gene where a C to T substitution occurs at position +85 in exon 12, a change known to enhance transactivation. The baseline characteristics of the patients were not different among genotype groups except for a significantly higher prevalence of shock and number of failed organs in T-allele carriers. A significant genotype-phenotype association was found for plasma levels of vascular endothelial growth factor-A but not angiopoietin-2, two downstream targets of HIF-1 alpha. Compared to the CC genotype, T-allele carriers had significantly higher adjusted odds for dialysis requirement or in-hospital death; assisted mechanical ventilation or dialysis requirement; and the composite of assisted mechanical ventilation, dialysis requirement or in-hospital death. The trend for higher plasma angiopoietin-2 levels was associated with significantly higher adjusted odds for in-hospital death; dialysis requirement or in-hospital death; and the composite outcome of assisted mechanical ventilation, dialysis, or in-hospital death. Despite the limited cohort size, our study found this particular HIF-1a genetic variant to be associated with disease severity and adverse outcomes in AKI. Larger studies are needed to confirm these relationships. Kidney International (2009) 75, 1322-1329; doi:10.1038/ki.2009.68; published online 11 March 2009