title: Inadequate therapy and antibiotic resistance. Risk factors for mortality in the intensive care unit.
abstract: BACKGROUND
  The impact of nosocomial infections and multidrug resistance on mortality is a topic of considerable controversy.
  
  
  METHODS
  A prospective, nested case control study was conducted in four intensive care units (ICUs) in Mexico to measure the impact of antibiotic resistance on and identify the main risk factors for mortality in critically ill patients with nosocomial infections.
  
  
  RESULTS
  One hundred thirteen patients developed 119 nosocomial infections. Multivariate analysis identified two variables that were significantly and independently associated with mortality: ventilator-associated pneumonia (p = 0.0041, odds ratio [OR] = 7.7) and inadequate antibiotic treatment (p <0.0001, OR = 70.5). Although antibiotic resistance in Gram-negative rods was not an independent risk factor for mortality, there was a strong association between antibiotic resistance and inadequate treatment (chi2 for linear trend = 29.3, p <0.00001). For patients with ventilator-associated pneumonia, predicted mortality calculated by APACHE II score was 23% compared to an observed mortality of 71%.
  
  
  CONCLUSIONS
  In this study the major risk factors for mortality were inadequate antibiotic treatment and development of ventilator-associated pneumonia. Multidrug resistance significantly increased the probability of receiving inadequate antibiotic treatment. The striking differences between observed and predicted mortality in these four ICUs indicate the need for further research and a reassessment of the current programs for prevention and control of nosocomial infections in Mexico.
authors.affiliation: Departamento de Investigación y Cuidados Intensivos, Hospital General O'Horan, Mérida, Yucatán, Mexico. mbzaidi@yuc.quik.com
authors.forename: Mussaret
authors.initials: M
authors.lastname: Zaidi
authors.forename: José
authors.initials: J
authors.lastname: Sifuentes-Osornio
authors.forename: Ana Lilia
authors.initials: AL
authors.lastname: Rolón
authors.forename: Gabriela
authors.initials: G
authors.lastname: Vázquez
authors.forename: Rilke
authors.initials: R
authors.lastname: Rosado
authors.forename: Mauro
authors.initials: M
authors.lastname: Sánchez
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Calva
authors.forename: Samuel Ponce
authors.initials: SP
authors.lastname: de León-Rosales
mesh_terms: D016022:Case-Control Studies; D004352:Drug Resistance, Microbial; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D011446:Prospective Studies; D012307:Risk Factors