Several predictor variables showed a very weak but significant bivariate correlation with renal failure but did not fit in fully adjusted models, namely: ACE-inhibitors (Pearson correlation coefficient r = 0.082, p<0.001), beta-blockers (Pearson correlation coefficient r = 0.041, p = 0.001), hypertension (Pearson correlation coefficient r = 0.053, p = 0.001), and paracetamol (Pearson correlation coefficient r = 0.049, p = 0.001). This evidence concerns the gene ACE and acute kidney injury.