Mortality risk factors associated with healthcare infections in a tertiary level university hospital in Colombia

Introduction: Nosocomial infections are a public health threat. Despite multiple efforts, its incidence is still significant and it generates high costs in health care. Objective: To determine risk factors associated with mortality in patients with healthcare infections in a tertiary level hospital in Colombia. Materials and methods: A prospective cohort observational study was performed between January and December 2011. One thousand one hundred and fifteen patients with health care infections using the CDC definition criteria were included. Exclusion criteria were those patients with no microbiologic isolate associated with the infection or hospital readmissions in the last year. Socio-demographic and clinical variables, bacterial resistance profiles and antibiotic use were evaluated. Death was the primary outcome. Survival analysis for each variable was performed using statistical significance defined by the log-rank test. Multivariate and Cox regression analyses were done. Values of p less than 0.05 were considered statistically significant. Results: Mean age was 43 years old (57% men and 47% women); 53% of patients had a medical condition and 47% surgical diagnosis; 54% of health care infections were surgical site infections and 62% were associated to Gram-negative bacilli. The mortality rate during follow-up was 24.4%. On multivariate analysis we found an association with intensive care stay (HR=1.51; 95% CI: 1.13-2.01), inappropriate use of antibiotics (HR=3.05; 95% CI: 2.34-3.98) and use of generic antibiotics or copies (HR=1.91; 95% CI: 1.43-2.55). Conclusions: The use of generic molecules of antibiotics and inappropriate antibiotic treatments in patients with health care infections are modifiable factors to decrease mortality.