title: Triglyceride to HDL ratio is a reliable predictor of adverse outcomes in risk stratification for candidates undergoing abdominal aortic surgery.
abstract: BACKGROUND
  The aim of this study was to establish if an elevated triglyceride to high-density lipoprotein (HDL) ratio (THR) is not only a risk factor for cardiovascular and overall morbidity as the updated evidence shows, but could also be employed as a significant predictor for surgical adverse outcomes and hence be a valid tool for risk stratification of candidates undergoing abdominal aortic surgery.
  
  
  METHODS
  This is a single-centre retrospective analysis of 2224 patients who underwent open abdominal aortic surgery between January 1996 and 2009. This cohort was divided into quartiles of THR. A list of covariates has been entered with THR into a multiple logistic model with forwards stepwise selection. The obtained result is an adjusted model, conceived to establish the association between THR and perioperative adverse events. Discrimination of the model so obtained and comparison with vascular-specific risk stratification scoring systems were evaluated using the area under the receiver operating characteristic (AUROC).
  
  
  RESULTS
  THR had the highest predictive value for the outcomes of interest. The adjusted odds ratios (ORs) per every 0.1 augmentation of THR were 1.41 (1.08-1.88) for cardiac, 1.38 (1.09-1.84) for respiratory, 1.27 (1.06-1.54) for renal adverse events and 1.02 (0.84-1.23) for mortality. Regarding mortality, either of the scoring systems Vascular Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) and customised probability index (CPI) and the THR ranked as moderate discriminators, with THR performing the worst (AUROC 0.71) compared with Vascular POSSUM (AUROC 0.76) and CPI (AUROC 0.78). THR performed as a very strong predictor of morbidity (AUROC 0.86), ranking above Vascular POSSUM (AUROC 0.72).
  
  
  CONCLUSIONS
  THR is a significant predictor of perioperative morbidity and mortality. THR offers a broad outlook on the metabolic state of patients undergoing major abdominal aortic surgery and hence their propensity to adverse events, allowing us to risk-stratify the prognostic outcome of surgical intervention and possibly intervene preoperatively to optimise results.
authors.affiliation: Department of Vascular and Endovascular Surgery, Royal Victoria Hospital, Grosvenor Road, Belfast BT12 6BA,United Kingdom. ivangambardella@hotmail.it
authors.forename: I
authors.initials: I
authors.lastname: Gambardella
authors.forename: P H
authors.initials: PH
authors.lastname: Blair
authors.forename: A
authors.initials: A
authors.lastname: McKinley
authors.forename: R
authors.initials: R
authors.lastname: Baker
authors.forename: D W
authors.initials: DW
authors.lastname: Harkin
mesh_terms: D000368:Aged; D001012:Aorta, Abdominal / Q000601:surgery*; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology* / Q000401:mortality; D016002:Discriminant Analysis; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000097:blood / Q000209:etiology; D008075:Lipoproteins, HDL / Q000097:blood*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009660:Northern Ireland; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012140:Respiratory Tract Diseases / Q000097:blood / Q000209:etiology; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood*; D015854:Up-Regulation; D014656:Vascular Surgical Procedures / Q000009:adverse effects* / Q000401:mortality
chemical_list: D015415:Biomarkers; D008075:Lipoproteins, HDL; D014280:Triglycerides