Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-29T16:04:36.488Z Has data issue: false hasContentIssue false

Staphylococcus aureus Bacteremia in Older Adults: Predictors of 7-Day Mortality and Infection With a Methicillin-Resistant Strain

Published online by Cambridge University Press:  21 June 2016

Mazen S. Bader*
Affiliation:
Division of Geriatric Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma Division of Microbiology and Infectious Diseases, Memorial University of Newfoundland Health Sciences Center, St. John's, Newfoundland, Canada
*
Memorial University of Newfoundland Health Sciences Center, Division of Microbiology and Infectious Diseases, 300 Prince Phillip Drive, Office 1J426, St. John's, Newfoundland A1B3V6, Canada ([email protected])

Abstract

Objectives.

To determine the predictors of 7-day mortality in older adult patients with Staphylococcus aureus bacteremia after controlling for comorbidity using the Charlson weighted index of comorbidity (WIC) and to identify the risk factors associated with bacteremia due to methicillin-resistant S. aureus (MRSA).

Design.

Retrospective cohort study from January 2003 until December 2004.

Setting.

Two tertiary care, university-affiliated hospitals.

Methods.

One hundred thirty-five hospitalized patients with S. aureus bacteremia were included in the study. All patients who were 60 years or older and had 1 or more blood cultures positive for S. aureus were included in the study. The primary outcome was death 7 days after the onset of S. aureus bacteremia.

Results.

Twenty-one patients (15.6%) died within 7 days after the onset of S. aureus bacteremia. Seventy-four patients (56.1%) had MRSA bacteremia. Multivariate analysis identified 3 independent determinants of 7-day mortality: Charlson WIC score greater than 5 (odds ratio [OR], 3.6 [95% confidence interval {CI}, 1.1-11.2]; P = .03), previous hospitalization in the past 3 months (OR, 5.0 [95% CI, 1.1-25.1]; P = .04), and altered mental status at the onset of S. aureus bacteremia (OR, 13.6 [95% CI, 2.9-64.6]; P = .001). Multivariate analysis identified .previous hospitalization in the past 3 months (OR, 2.6 [95% CI, 1.1-5.9]; P = .02), residence in a long-term care facility (OR, 4.5 [95% CI, 1.7-12.3]; P = .003), and altered mental status at the onset of S. aureus bacteremia (OR, 2.5 [95% CI, 1.5-5.6]; P = .02) to be independently associated with the presence of MRSA.

Conclusions.

The Charlson WIC is significantly associated with increased mortality of S. aureus bacteremia in older adults. Previous hospitalization in the past 3 months, residence in a long-term care facility, and altered mental status should be used as a guidance for empirical vancomycin therapy and application of infection control measures in older adults with suspected S. aureus bacteremia.

Type
Original Articles
Copyright
Copyright © The Society for Healthcare Epidemiology of America 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Mitchell, J. Primary Care Geriatrics. 4th ed. St. Louis, MO: Mosby; 2002:914.Google Scholar
2. Lyytikäinen, O, Ruotsalainen, E, Järvinen, A, Valtonen, V, Ruutu, P. Trends and outcome of nosocomial and community-acquired bloodstream infections due to Staphylococcus aureus in Finland, 1995-2001. Eur J Clin Microbiol Infect Dis 2005; 24:399404.CrossRefGoogle ScholarPubMed
3. Gavazzi, G, Mallaret, MR, Couturier, P, Iffenecker, A, Franco, A. Bloodstream infection: differences between young-old, old and old-old patients. J Am Geriatr Soc 2002; 50:16671673.Google Scholar
4. McClelland, RS, Fowler, VJ, Sanders, LL, et al. Staphylococcus aureus bacteremia among elderly vs. young adult patients: comparison of clinical features and mortality. Arch Intern Med 1999; 159:12441247.Google Scholar
5. Jensen, LG, Cartsen, H, Wachmann, CH, et al. Treatment and outcome of Staphylococcal aureus bacteremia. Arch Intern Med 2002; 162:2532.Google Scholar
6. Mylotte, JM, Tayara, A. Staphylococcus aureus bacteremia: predictors of 30-day mortality in a large cohort. Clin Infect Dis 2000; 31:11701174.Google Scholar
7. Soriano, A, Martinez, AJ, Mensa, J, et al. Pathogenic significance of methicillin resistance for patients with Staphylococcus aureus bacteremia. Clin Infect Dis 2000; 30:368373.CrossRefGoogle ScholarPubMed
8. Lesens, O, Methlin, C, Hansmann, Y, et al. Role of comorbidity in mortality related to Staphylococcus aureus bacteremia: a prospective study using the Charlson weighted index of comorbidity. Infect Control Hosp Epidemiol 2003; 24:890896.Google Scholar
9. Kuehnerst, MJ, Hill, HA, Kupronis, BA, Tokars, JI, Solomon, SL, Jernigan, DB. Methicillin-resistant Staphylococcus aureus hospitalization, United States. Emerg Infect Dis 2005; 11:868872.Google Scholar
10. Papia, G, Louie, M, Tralla, A, et al. Screening high-risk patients for methicillin-resistant Staphylococcus aureus: is it cost-effective? Infect Control Hosp Epidemiol 1999; 20:473477.Google Scholar
11. Charlson, ME, Pompei, P, Ales, KL, MacKinzie, CR. A new method for classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis 1987; 40:373383.Google Scholar
12. Le Gall, JR, Lemeshow, S, Saulnier, F. A new Simplified Acute Physiology Score (SAPS II) based on a European/North American multicenter study. JAMA 1993; 270:29572963.Google Scholar
13. Romero-vivas, J, Rubio, M, Fernandez, C, Picazo, JJ. Mortality associated with nosocomial bacteremia due to methicillin-resistant Staphylococcus aureus . Clin Infect Dis 1995; 21:14171423.CrossRefGoogle ScholarPubMed
14. McCabe, WR, Jackson, GG. Gram-negative bacteremia: etiology and ecology. Arch Intern Med 1962; 110:847855.Google Scholar
15. Soufir, L, Timsit, JF, Mahe, C, Carlet, J, Regnier, B, Chevret, S. Attributable morbidity and mortality of catheter-related septicemia in critically ill patients: a matched, risk-adjusted, cohort study. Infect Control Hosp Epidemiol 1999; 20:396401.Google Scholar
16. McGregor, JC, Kim, PW, Perencevich, EN, et al. Utility of the Chronic Disease Score and Charlson Comorbidity Index as comorbidity measures for use in epidemiologic studies of antibiotic-resistant organisms. Am J Epidemiol 2005; 161:483493.CrossRefGoogle ScholarPubMed
17. Scanvic, A, Denic, L, Gaillon, S, Giry, P, Andremont, A, Lucet, JC. Duration of colonization by methicillin-resistant Staphylococcus aureus after hospital discharge and risk factors for prolonged carriage. Clin Infect Dis 2001;32:13931398.Google Scholar
18. Warshawsky, B, Hussain, Z, Gregson, DB, et al. Hospital- and community-based surveillance of methicillin-resistant Staphylococcus aureus: previous hospitalization is the major risk factor. Infect Control Hosp Epidemiol 2000;21:724727.Google Scholar
19. Morin, CA, Hadler, JL. Population-based incidence and characteristics of community-onset Staphylococcus aureus infections with bacteremia in 4 metropolitan Connecticut areas, 1998. J Infect Dis 2001; 184:10291034.Google Scholar
20. Friedman, ND, Kaye, KS, Stout, JE, et al. Health care-associated bloodstream infections in adults: a reason to change the accepted definition of community-acquired infections. Ann Intern Med 2002; 137:791797.Google Scholar
21. Goetz, A, Posey, K, Fleming, J, et al. Methicillin-resistant Staphylococcus aureus in the community: a hospital-based study. Infect Control Hosp Epidemiol 1999; 20:689691.Google Scholar
22. Fatkenheuer, G, Preuss, M, Salzberger, B, et al. Long-term outcome and quality of care of patients with Staphylococcus aureus bacteremia. Eur J Clin Microbiol Infect Dis 2004; 23:157162.Google Scholar
23. Rezende, NA, Blumberg, HM, Metzger, BS, Larsen, NM, Ray, SM, McGowan, JE. Risk factors for methicillin-resistance among patients with Staphylococcus aureus bacteremia at the time of hospital admission. Am J Med Sci 2002; 323:117123.Google Scholar
24. Kim, SH, Park, WB, Lee, KD, et al. Outcome of inappropriate initial antimicrobial treatment in patients with methicillin-resistant Staphylococcus aureus bacteremia. J Antimicrob Chemother 2004; 54:489497.Google Scholar