Incidence and cost of hospitalizations associated with Staphylococcus aureus skin and soft tissue infections in the United States from 2001 through 2009

Background: The emergence of community-associated methicillin-resistant Staphylococcus aureus (SA) and its role in skin and soft tissue infections (SSTIs) accentuated the role of SA-SSTIs in hospitalizations. Methods: We used the Nationwide Inpatient Sample and Census Bureau data to quantify population-based incidence and associated cost for SA-SSTI hospitalizations. Results: SA-SSTI associated hospitalizations increased 123% from 160,811 to 358,212 between 2001 and 2009, and they represented an increasing share of SA- hospitalizations (39% to 51%). SA-SSTI incidence (per 100,000 people) doubled from 57 in 2001 to 117 in 2009 (p < 0.01). A significant increase was observed in all age groups. Adults aged 75+ years and children 0-17 years experienced the lowest (27%) and highest (305%) incidence increase, respectively. However, the oldest age group still had the highest SA-SSTI hospitalization incidence across all study years. Total annual cost of SA-SSTI hospitalizations also increased and peaked in 2008 at $4.84 billion, a 44% increase from 2001. In 2009, the average associated cost of a SA-SSTI hospitalization was $11,622 (SE = $200). Conclusion: There has been an increase in the incidence and associated cost of SA-SSTI hospitalizations in U.S.A. between 2001 and 2009, with the highest incidence increase seen in children 0-17 years. However, the greatest burden was still seen in the population over 75 years. By 2009, SSTI diagnoses were present in about half of all SA-hospitalizations.