Abstract:ObjectiveTo assess the risk factors of multidrugresistant organism(MDRO) healthcareassociated pneumonia(HCAP). MethodsThe casecontrol study was conducted in patients admitted to 22 hospitals in 4 cities between April 1, 2013 and December 31, 2013,patients with HCAP caused by MDRO (MRSA,MDRPA,MDRAB,ESBL KP, ESBL E.coli)(drugresistant group )and drugsensitive organisms (MSSA, PA,AB,KP,E.coli)(drugsensitive group )were surveyed . Univariate and multivariate statistical analysis methods were used to evaluate the risk factors for MDRO HCAP. The prognosis, cost and length of hospital stay between drugresistant group and drugsensitive group were compared . ResultsA total of 1 656 patients were included in the study ,including 43 patients (2.60%)with mixed infection caused by both drugresistant and drugsensitive organisms ;there were 927 cases (55.98%)in drugresistant group and 772 cases(46.62%)in drugsensitive group . Logistic regression model revealed that admission to ICUs (OR 95%CI:1.55[1.14-2.11]), mechanical ventilation (OR 95%CI:1.45[1.15-1.84]), arteriovenous catheterization (OR 95%CI:1.29[1.02-1.63]), fiberbronchoscopy (OR 95%CI:1.46[1.02-2.09]), antimicrobial use(OR 95%CI:1.63[1.20-2.22]) , chronic lung diseases (OR 95%CI:1.54[1.13-2.10]), and chronic cardiovascular and cerebrovascular diseases (OR 95%CI:1.42[1.15-1.74])were independent risk factors for MDRO HCAP .Compared with drugsensitive group , drugresistant group prolonged length of hospital stay by an average of 5.89 days, increased hospitalization and antimicrobial expense by ¥40 739.30 and ¥2 805.80 respectively; prognoses was worse, risk factor was 1.66fold of drugsensitive group(OR 95%CI:1.16-2.35).ConclusionAdmission to ICUs, invasive operations, antimicrobial use, chronic lung diseases and chronic cardiovascular and cerebrovascular diseases can increase the risk of MDRO HCAP .