Abstract
BackgroundInvestigations of the impact of ethnicity and socio-economic status on incidence and outcomes of Staphylococcus aureus bacteraemia are limited.MethodsWe prospectively identified all S. aureus bacteraemia episodes in the Australian New Zealand Cooperative on Outcomes in Staphylococcal Sepsis cohort study between 2007 and 2010. We calculated population level incidence rates using regional postcodes and stratified the analysis by ethnicity, age and socio-economic status indexes.ResultsThere were 7539 episodes of S. aureus bacteraemia with an annual incidence of 11·2 episodes per 100,000 population. The age-adjusted incidence in the Indigenous population was 62·5 per 100,000 population with an age standardized incidence rate ratio of 5·9 compared to the non-Indigenous population and an incidence rate ratio of 29.2 for community-associated methicillin-resistant S. aureus (MRSA). Populations in the lowest socio-economic status quintile had an increased S. aureus bacteraemia incidence compared to higher quintiles. However, there was a disparity between Indigenous and non-Indigenous populations across all socio-economic status quintiles. The lower 30-day mortality for Indigenous patients (7%) compared to non-Indigenous patients (17%) was explained by differences in age.ConclusionsIndigenous Australians suffer from a higher rate of S. aureus bacteraemia than non-Indigenous Australians, particularly for community-associated MRSA. Ethnicity and socio-economic status had little impact on subsequent mortality, with other host factors contributing more significantly.
Highlights
Investigations of the impact of ethnicity and socio-economic status on incidence and outcomes of Staphylococcus aureus bacteraemia are limited
The numbers of cases within the quintiles for the Indigenous population were 227, 29, 77, 149 and 54 for Population level incidence of S. aureus bacteremia There were 7633 S. aureus bacteraemia (SAB) episodes identified from 24 participating institutions in Australia over the four years 2007–2010 from the Australian New Zealand Cooperative on Outcomes in Staphylococcal Sepsis study. 94 (1%) episodes were excluded as postcodes were incomplete or not represented in the 2006 Australian census
The differences between non-Indigenous and Indigenous populations existed across all Index of Relative Socioeconomic Advantage and Disadvantage” (IRSAD) quintiles with age standardized incidence rate ratio (IRR) ranging from 1Á9 to 8.5 for Indigenous compared to non-Indigenous rates
Summary
Investigations of the impact of ethnicity and socio-economic status on incidence and outcomes of Staphylococcus aureus bacteraemia are limited. Socio-economic status (SES) is known to impact infectious diseases rates through differences in living conditions, including household crowding and access to and use of washing and sanitation facilities, differences in comorbidities such as smoking, hazardous alcohol use and diabetes, access to health care facilities and differing health seeking behaviour. Previous studies have found lower income households [5] and those living in public housing complexes [4] to be at higher risk of acquiring community-associated MRSA infections or MRSA post-operative wound infections [9]; and compared to lower SES strata, SAB occurred significantly less frequently in higher SES strata [10]. In Australia, a correlation between lower SES and the incidence of staphylococcal infections has been observed [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
