14-Year Survey in a Swedish County Reveals a Pronounced Increase in Bloodstream Infections (BSI). Comorbidity - An Independent Risk Factor for Both BSI and Mortality.

Martin Holmbom,Mats Fredrikson,Håkan Hanberger,Mikael Hoffmann,Christian G Giske,Åse Östholm Balkhed,Lennart E Nilsson,Carina Claesson,Jan Kluytmans

doi:10.1371/journal.pone.0166527

Abstract

Objectiveswe assessed the incidence, risk factors and outcome of BSI over a 14-year period (2000–2013) in a Swedish county.Methodsretrospective cohort study on culture confirmed BSI among patients in the county of Östergötland, Sweden, with approximately 440,000 inhabitants. A BSI was defined as either community-onset BSI (CO-BSI) or hospital-acquired BSI (HA-BSI).Resultsof a total of 11,480 BSIs, 67% were CO-BSI and 33% HA-BSI. The incidence of BSI increased by 64% from 945 to 1,546 per 100,000 hospital admissions per year during the study period. The most prominent increase, 83% was observed within the CO-BSI cohort whilst HA-BSI increased by 32%. Prescriptions of antibiotics in outpatient care decreased with 24% from 422 to 322 prescriptions dispensed/1,000 inhabitants/year, whereas antibiotics prescribed in hospital increased by 67% (from 424 to 709 DDD per 1,000 days of care). The overall 30-day mortality for HA-BSIs was 17.2%, compared to 10.6% for CO-BSIs, with an average yearly increase per 100,000 hospital admissions of 2 and 5% respectively. The proportion of patients with one or more comorbidities, increased from 20.8 to 55.3%. In multivariate analyses, risk factors for mortality within 30 days were: HA-BSI (2.22); two or more comorbidities (1.89); single comorbidity (1.56); CO-BSI (1.21); male (1.05); and high age (1.04).Conclusionthis survey revealed an alarming increase in the incidence of BSI over the 14-year study period. Interventions to decrease BSI in general should be considered together with robust antibiotic stewardship programmes to avoid both over- and underuse of antibiotics.

Highlights

Bloodstream infection (BSI) is a major cause of morbidity and mortality worldwide and several measures have been taken to prevent BSI and increase survival in sepsis [1,2,3,4,5]
A BSI was defined as either community-onset BSI (CO-BSI) or hospital-acquired BSI (HA-BSI)
Prescriptions of antibiotics in outpatient care decreased with 24% from 422 to 322 prescriptions dispensed/1,000 inhabitants/year, whereas antibiotics prescribed in hospital increased by 67%

Summary

Introduction

Bloodstream infection (BSI) is a major cause of morbidity and mortality worldwide and several measures have been taken to prevent BSI and increase survival in sepsis [1,2,3,4,5]. The exact burden of BSI worldwide is difficult to estimate since the incidence of community-onset BSI in low- and middle-income country populations is not known due to lack of population-based BSI studies in these countries [7]. Most studies in high-income countries show continual increases in the incidence of sepsis [8,9,10,11,12,13,14,15,16,17]. A decrease in mortality associated with BSI has been reported in some studies from high income countries [18, 19], but increased mortality in others [10]. In this study we assessed the incidence, risk factors and outcome of all BSIs over a 14-year period in a county in Sweden having four hospitals and almost half a million inhabitants. BSIs were defined as either hospital-acquired or community-onset

Methods

Results

Conclusion