Risk factors for acute respiratory distress syndrome development in patients with type A influenza (H1N1)

Abstract

Introduction. Acute respiratory distress syndrome (ARDS) is a significant complication in patients with type A influenza (H1N1) due to the severity of the disease and adverse outcome. Objective. The aim of the study was to identify risk factors for the development of ARDS in patients with type A influenza (H1N1) and outcome of ARDS. Methods. The research was conducted as a case series study, and included patients admitted at the Clinical Center in Kragujevac during the 2009 and 2010 flu season. Data for the study were obtained from patients’ medical records, inclusion criteria having been determined in accordance with recommendations of the Expert Methodological Guide for Controlling Spread of Pandemic Influenza in the Republic of Serbia. Primary data analysis was performed using descriptive statistics and a statistical method for testing hypotheses. Dependence analysis was performed using simple logistic regression. The statistical hypotheses were tested at the 0.05 level of significance. Results. The case group consisted of 14 patients who developed ARDS, while the control group was composed of 34 patients with influenza but without ARDS (group alignment performed by age). Simple logistic regression analysis identified the following risk factors for the development of ARDS: diabetes mellitus type 1 or 2 (p=0.028), high levels of C-reactive protein (p=0.004), aspartate-aminotransferase (p=0.006), urea (p=0.028), creatine kinase (p=0.001), lactate-dehydrogenase (p=0.005) and longer time elapsed from disease symptoms onset to the administration of specific antiviral therapy administration (p=0.021). Conclusion. The research showed that diabetes, late initiation of antiviral therapy and some laboratory tests are risk factors for ARDS development in patients with type A influenza (H1N1).

Keywords

• influenza A (H1N1)
• acute respiratory distress syndrome(ARDS)
• risk factors