title: Effect of increasing patient age on complication rates following intact abdominal aortic aneurysm repair in the United States.
abstract: BACKGROUND
  Advanced age is generally acknowledged as a risk factor for adverse surgical outcomes, but little information exists to define the magnitude of this association from a population-based perspective. This study was undertaken to determine the relation of patient age to complications following abdominal aortic aneurysm (AAA) repair in a population-based experience.
  
  
  METHODS
  This study was based upon data from 6397 patients with a primary diagnosis of intact AAA and a procedure code for repair of AAA from the Nationwide Inpatient Sample (NIS) in 2000. The NIS is a 20% stratified random sample representative of all United States hospitals. Primary outcome variables were postoperative complications determined from secondary diagnostic codes. Adjustment for confounding variables was performed using multiple logistic regression.
  
  
  RESULTS
  At least one complication affected 29% of patients. Increasing age correlated with a higher risk of having one or more complications (51-60 years, 18.8%; 61-70 years, 27.3%; 71-80 years, 31.2%; >80 years, 34.3%; P < 0.01). Comparison of the oldest to the youngest age group revealed an increased incidence of pulmonary insufficiency (13.9% versus 6.4%), pneumonia (7.7% versus 3.0%), reintubation (9.5% versus 3.9%), acute renal failure (8.8% versus 2.5%), myocardial infarction (4.3% versus 1.6%), and mortality (7.9% versus 1.1%). The association of increasing age to complications and mortality persisted after adjusting for patient case-mix.
  
  
  CONCLUSIONS
  Older patient age is independently associated with an increased risk of major postoperative complications after AAA repair. The increasing age of the United States population will compound this healthcare problem. Quality improvement efforts must focus on minimizing complication rates in elderly patients undergoing common vascular surgical procedures including AAA repair.
authors.affiliation: Surgical Outcomes Research Team, Section of Vascular Surgery, Department of Surgery, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors.forename: Chandu
authors.initials: C
authors.lastname: Vemuri
authors.forename: Reid M
authors.initials: RM
authors.lastname: Wainess
authors.forename: Justin B
authors.initials: JB
authors.lastname: Dimick
authors.forename: John A
authors.initials: JA
authors.lastname: Cowan
authors.forename: Peter K
authors.initials: PK
authors.lastname: Henke
authors.forename: James C
authors.initials: JC
authors.lastname: Stanley
authors.forename: Gilbert R
authors.initials: GR
authors.lastname: Upchurch
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D007239:Infections / Q000453:epidemiology / Q000209:etiology; D008875:Middle Aged; D011014:Pneumonia / Q000453:epidemiology / Q000209:etiology; D012131:Respiratory Insufficiency / Q000453:epidemiology / Q000209:etiology; D014481:United States; D014656:Vascular Surgical Procedures / Q000009:adverse effects*