title: Prognostic factors for morbidity and mortality in elderly patients undergoing acute gastrointestinal surgery: a systematic review.
abstract: BACKGROUND
  Elderly patients undergoing acute gastrointestinal (GI) surgery experience increased morbidity and mortality compared with younger and elective patients. Prognostic factors can be used to counsel patients of these risks and, if modifiable, to minimize them. We reviewed the literature on prognostic factors for adverse outcomes in elderly patients undergoing acute GI surgery.
  
  
  METHODS
  We searched PubMed and Embase using a strategy developed in collaboration with an expert librarian. Studies examining independent associations between prognostic factors and morbidity or mortality in patients aged 65 and older undergoing acute GI surgery were selected. We extracted data using a standardized form and assessed study quality using the QUIPS tool.
  
  
  RESULTS
  Nine cohort studies representing 2958 patients satisfied our selection criteria. All studies focused on postoperative mortality. Thirty-four prognostic factors were examined, with significant variability across studies. There was limited or conflicting evidence for most prognostic factors. Meta-analysis was only possible for the American Society of Anesthesiologists (ASA) score, which was found to be associated with mortality in 4 studies (pooled odds ratio 2.77, 95% confidence interval 0.92-8.41).
  
  
  CONCLUSIONS
  While acute GI surgery in elderly patients is becoming increasingly common, the literature on prognostic factors for morbidity and mortality in this patient population lags behind. Further research is needed to help guide patient care and potentially improve outcomes.
authors.affiliation: The Faculty of Medicine, Departments of Emergency Medicine Dalhousie University, Halifax, NS.
authors.forename: Philip
authors.initials: P
authors.lastname: Davis
authors.affiliation: Community Health and Epidemiology and Dalhousie University, Halifax, NS.
authors.forename: Jill
authors.initials: J
authors.lastname: Hayden
authors.affiliation: The Division of General Surgery, Dalhousie University, Halifax, NS.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Springer
authors.affiliation: The Division of General Surgery, Dalhousie University, Halifax, NS.
authors.forename: Jonathon
authors.initials: J
authors.lastname: Bailey
authors.affiliation: The Division of General Surgery, Dalhousie University, Halifax, NS.
authors.forename: Michele
authors.initials: M
authors.lastname: Molinari
authors.affiliation: The Division of General Surgery, Dalhousie University, Halifax, NS.
authors.forename: Paul
authors.initials: P
authors.lastname: Johnson
mesh_terms: D000367:Age Factors; D000368:Aged; D013505:Digestive System Surgical Procedures / Q000009:adverse effects* / Q000401:mortality*; D006801:Humans; D011379:Prognosis