Age- and sex-associated trends in bloodstream infection: a population-based study in Olmsted County, Minnesota.

BACKGROUND Despite increasing concerns about antimicrobial resistance and emerging pathogens among blood culture isolates, contemporary population-based data on the age- and sex-specific incidence of bloodstream infections (BSIs) are limited. METHODS Retrospective, population-based, cohort study of all residents of Olmsted County, Minnesota, with a BSI between January 1, 2003, and December 31, 2005. The medical record linkage system of the Rochester Epidemiology Project and microbiology records were used to identify incident cases. RESULTS A total of 1051 unique patients with positive blood culture results were identified; 401 (38.2%) were classified as contaminated. Of 650 patients with cultures deemed clinically relevant, the mean +/- SD age was 63.1 +/- 23.1 years, and 52.5% were male. The most common organisms identified were Escherichia coli (in 163 patients with BSIs [25.1%]) and Staphylococcus aureus (in 108 patients with BSIs [16.6%]). Nosocomial BSIs were more common in males than females (23.8% vs 13.9%; P = .002). The age-adjusted incidence rate of BSI was 156 per 100 000 person-years for females and 237 per 100 000 person-years for males (P<.001), with an age- and sex-adjusted rate of 189 per 100 000 person-years. Rates of BSI due to gram-positive cocci were 64 per 100 000 person-years for females and 133 per 100 000 person-years for males (P<.001); gram-negative bacillus BSI rates (85/100 000 person-years for females and 79/100 000 person-years for males) were not significantly different between sexes (P = .79). The rate of S aureus BSI was 23 per 100 000 person-years for females and 46 per 100 000 person-years for males (P = .005). CONCLUSIONS There are significant differences in the age and sex distribution of organisms among patients with BSIs. The incidence of BSI increases sharply with increasing age and is significantly higher in males, mainly because of nosocomial organisms, including S aureus.

[1]  Paul N Valenstein,et al.  Trends in blood culture contamination: a College of American Pathologists Q-Tracks study of 356 institutions. , 2005, Archives of pathology & laboratory medicine.

[2]  Bruno Hoen,et al.  Staphylococcus aureus native valve infective endocarditis: report of 566 episodes from the International Collaboration on Endocarditis Merged Database. , 2005, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[3]  K. Anstrom,et al.  Staphylococcus aureus endocarditis: a consequence of medical progress. , 2005, JAMA.

[4]  Walter R Wilson,et al.  Temporal trends in infective endocarditis: a population-based study in Olmsted County, Minnesota. , 2005, JAMA.

[5]  R. Wenzel,et al.  Nosocomial bloodstream infections in US hospitals: analysis of 24,179 cases from a prospective nationwide surveillance study. , 2004, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[6]  W. Harmsen,et al.  Optimal testing parameters for blood cultures. , 2004, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[7]  C. Woods,et al.  Clinical identifiers of complicated Staphylococcus aureus bacteremia. , 2003, Archives of internal medicine.

[8]  H. SchØNheyder,et al.  Incidence and Short-term Prognosis of Infective Endocarditis in Denmark, 1980-1997 , 2003, Scandinavian journal of infectious diseases.

[9]  Daniel J Sexton,et al.  Health CareAssociated Bloodstream Infections in Adults: A Reason To Change the Accepted Definition of Community-Acquired Infections , 2002, Annals of Internal Medicine.

[10]  C. Selton-Suty,et al.  Changing profile of infective endocarditis: results of a 1-year survey in France☆ , 2002 .

[11]  F. Alla,et al.  Changing profile of infective endocarditis: results of a 1-year survey in France. , 2002, JAMA.

[12]  Michael L Wilson,et al.  Relevance of the Number of Positive Bottles in Determining Clinical Significance of Coagulase-Negative Staphylococci in Blood Cultures , 2001, Journal of Clinical Microbiology.

[13]  H. Sørensen,et al.  Community-acquired bacteraemia and antibiotic resistance. Trends during a 17-year period in a Danish county. , 2000, Danish medical bulletin.

[14]  R C George,et al.  Bacteraemia and antibiotic resistance of its pathogens reported in England and Wales between 1990 and 1998: trend analysis , 2000, BMJ : British Medical Journal.

[15]  D. Maraganore,et al.  Incidence and distribution of parkinsonism in Olmsted County, Minnesota, 1976–1990 , 1999, Neurology.

[16]  H. SchØNheyder,et al.  Secular trends in incidence and mortality of bacteraemia in a Danish county 1981–1994 , 1999, APMIS : acta pathologica, microbiologica, et immunologica Scandinavica.

[17]  A. Conde.  Staphylococcus aureus infections. , 1998, The New England journal of medicine.

[18]  M. Tvede,et al.  Infective endocarditis, 1984 through 1993: a clinical and microbiological survey , 1997, Journal of internal medicine.

[19]  D. Ilstrup,et al.  Analysis of 281,797 consecutive blood cultures performed over an eight-year period: trends in microorganisms isolated and the value of anaerobic culture of blood. , 1997, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[20]  A. Jensen,et al.  Increasing frequency of vertebral osteomyelitis following Staphylococcus aureus bacteraemia in Denmark 1980-1990. , 1997, The Journal of infection.

[21]  J. Steinberg,et al.  Nosocomial and community-acquired Staphylococcus aureus bacteremias from 1980 to 1993: impact of intravascular devices and methicillin resistance. , 1996, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[22]  L. Melton,et al.  History of the Rochester Epidemiology Project. , 1996, Mayo Clinic proceedings.

[23]  R. Wenzel,et al.  Long-term survival and function after suspected gram-negative sepsis. , 1995, JAMA.

[24]  D. Bates,et al.  How bad are bacteremia and sepsis? Outcomes in a cohort with suspected bacteremia. , 1995, Archives of internal medicine.

[25]  W J Martone,et al.  Secular trends in nosocomial primary bloodstream infections in the United States, 1980-1989. National Nosocomial Infections Surveillance System. , 1991, The American journal of medicine.

[26]  L Goldman,et al.  Contaminant blood cultures and resource utilization. The true consequences of false-positive results. , 1991, JAMA.

[27]  L. Melton,et al.  Influence of referral bias on the apparent clinical spectrum of infective endocarditis. , 1990, The American journal of medicine.

[28]  M. Aronson,et al.  Diagnostic Decision: Blood Cultures , 1987 .

[29]  W. Edwards,et al.  Infective endocarditis. Olmsted County, Minnesota, 1950 through 1981. , 1985, JAMA.

[30]  R. Macgregor,et al.  Evaluation of positive blood cultures. Guidelines for early differentiation of contaminated from valid positive cultures. , 1972, Archives of internal medicine.

[31]  H T Sørensen,et al.  Antibiotic therapy and outcome of monomicrobial gram-negative bacteraemia: a 3-year population-based study. , 1997, Scandinavian journal of infectious diseases.

[32]  M. Fernández-Guerrero,et al.  Hospital-acquired infectious endocarditis not associated with cardiac surgery: an emerging problem. , 1995, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[33]  M. Weinstein,et al.  The clinical significance of positive blood cultures: a comprehensive analysis of 500 episodes of bacteremia and fungemia in adults. II. Clinical observations, with special reference to factors influencing prognosis. , 1983, Reviews of infectious diseases.

[34]  R. Fairbrother.  Blood cultures. , 1949, The Practitioner.