title: Simplification of the pulmonary embolism severity index for prognostication in patients with acute symptomatic pulmonary embolism.
abstract: BACKGROUND
  The Pulmonary Embolism Severity Index (PESI) estimates the risk of 30-day mortality in patients with acute pulmonary embolism (PE). We constructed a simplified version of the PESI.
  
  
  METHODS
  The study retrospectively developed a simplified PESI clinical prediction rule for estimating the risk of 30-day mortality in a derivation cohort of Spanish outpatients. Simplified and original PESI performances were compared in the derivation cohort. The simplified PESI underwent retrospective external validation in an independent multinational cohort (Registro Informatizado de la Enfermedad Tromboembólica [RIETE] cohort) of outpatients.
  
  
  RESULTS
  In the derivation data set, univariate logistic regression of the original 11 PESI variables led to the removal of variables that did not reach statistical significance and subsequently produced the simplified PESI that contained the variables of age, cancer, chronic cardiopulmonary disease, heart rate, systolic blood pressure, and oxyhemoglobin saturation levels. The prognostic accuracy of the original and simplified PESI scores did not differ (area under the curve, 0.75 [95% confidence interval (CI), 0.69-0.80]). The 305 of 995 patients (30.7%) who were classified as low risk by the simplified PESI had a 30-day mortality of 1.0% (95% CI, 0.0%-2.1%) compared with 10.9% (8.5%-13.2%) in the high-risk group. In the RIETE validation cohort, 2569 of 7106 patients (36.2%) who were classified as low risk by the simplified PESI had a 30-day mortality of 1.1% (95% CI, 0.7%-1.5%) compared with 8.9% (8.1%-9.8%) in the high-risk group.
  
  
  CONCLUSIONS
  The simplified PESI has similar prognostic accuracy and clinical utility and greater ease of use compared with the original PESI.
authors.affiliation: Respiratory Department , Hospital Ramón y Cajal and Alcalá de Henares University, 28034 Madrid, Spain. djc_69_98@yahoo.com
authors.forename: David
authors.initials: D
authors.lastname: Jiménez
authors.forename: Drahomir
authors.initials: D
authors.lastname: Aujesky
authors.forename: Lisa
authors.initials: L
authors.lastname: Moores
authors.forename: Vicente
authors.initials: V
authors.lastname: Gómez
authors.forename: José Luis
authors.initials: JL
authors.lastname: Lobo
authors.forename: Fernando
authors.initials: F
authors.lastname: Uresandi
authors.forename: Remedios
authors.initials: R
authors.lastname: Otero
authors.forename: Manuel
authors.initials: M
authors.lastname: Monreal
authors.forename: Alfonso
authors.initials: A
authors.lastname: Muriel
authors.forename: Roger D
authors.initials: RD
authors.lastname: Yusen
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010045:Outpatients / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000401:mortality* / Q000503:physiopathology; D012372:ROC Curve; D012042:Registries; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013030:Spain / Q000453:epidemiology