Skip to main content Accessibility help

Are There Differences in Hospital Cost Between Patients With Nosocomial Methicillin-Resistant Staphylococcus aureus Bloodstream Infection and Those With Methicillin-Susceptible S. aureus Bloodstream Infection?

  • Debby Ben-David (a1) (a2) (a3), Ilya Novikov (a4) and Leonard A. Mermel (a1) (a2)



To examine the impact of methicillin resistance on in-hospital mortality, length of stay, and hospital cost after the onset of nosocomial Staphylococcus aureus bloodstream infection (BSI).


A retrospective cohort study.


A tertiary care hospital in Rhode Island.


A cohort of 182 consecutive patients who developed nosocomial BSI due to methicillin-susceptible and methicillin-resistant S. aureus (MSSA and MRSA, respectively)


Patients with MRSA BSI had a significantly longer total length of hospital and intensive care unit (ICU) stay before the onset of BSI and a higher average daily cost. Compared with ICU patients with MSSA BSI, those with MRSA BSI had a higher median total hospital cost ($42,137 vs $113,852), higher hospital cost after infection ($17,603 vs $51,492), and greater length of stay after infection (10.5 vs 20.5 days). After multivariable adjustment, ICU patients with MRSA BSI had significantly increased total hospital cost, hospital cost after infection, and length of stay after infection. However, using a propensity score approach, we found that, among ICU patients, the difference in cost after infection and the difference in length of stay after infection for MRSA, compared with MSSA BSI, were not significant. The differences among non-ICU patients who developed MRSA or MSSA BSI were not significant after multivariable adjustment or by propensity score.


On the basis of propensity score, we found that methicillin resistance did not independently increase hospital cost or length of stay after onset of S. aureus BSI. We believe that use of a propensity score on a comparable subset of patients may be a better method than multivariable adjustment for assessing the impact of methicillin resistance in cohort studies.


Corresponding author

Department of Infectious Diseases, Sheba Medical Center, Tel Hashomer, Israel (


Hide All
1.Diekema, DJ, Pfaller, MA, Schmitz, FJ, et al. Survey of infections due to Staphylococcus species: frequency of occurrence and antimicrobial susceptibility of isolates collected in the United States, Canada, Latin America, Europe, and the Western Pacific region for the SENTRY Antimicrobial Surveillance Program, 1997-1999. Clin Infect Dis 2001;32(Suppl 2):S114S132.
2.Fluit, AC, Wielders, CL, Verhoef, J, Schmitz, FJ. Epidemiology and susceptibility of 3,051 Staphylococcus aureus isolates from 25 university hospitals participating in the European SENTRY study. J Clin Microbiol 2001;39:37273732.
3.Allard, C, Carignan, A, Bergevin, M, et al. Secular changes in incidence and mortality associated with Staphylococcus aureus bacteraemia in Quebec, Canada, 1991-2005. Clin Microbiol Infect 2008;14:421428.
4.Klevens, RM, Morrison, MA, Nadle, J, et al. Invasive methicillin-resistant Staphylococcus aureus infections in the United States. JAMA 2007;298:17631771.
5.National Nosocomial Infections Surveillance (NNIS) System Report, data summary from lanuary 1992 through June 2003, issued August 2003. Am J Infect Control 2003;31:481498.
6.Fridkin, SK, Hill, HA, Volkova, NV, et al. Temporal changes in prevalence of antimicrobial resistance in 23 US hospitals. Emerg Infect Dis 2002;8:697701.
7.Cosgrove, SE, Sakoulas, G, Perencevich, EN, Schwaber, MJ, Karchmer, AW, Carmeli, Y. Comparison of mortality associated with methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteremia: a metaanalysis. Clin Infect Dis 2003;36:5359.
8.Whitby, M, McLaws, ML, Berry, G. Risk of death from methicillin-resistant Staphylococcus aureus bacteraemia: a meta-analysis. Med J Aust 2001;175:264267.
9.Kim, T, Oh, PI, Simor, AE. The economic impact of methicillin-resistant Staphylococcus aureus in Canadian hospitals. Infect Control Hosp Epidemiol 2001;22:99104.
10.Abramson, MA, Sexton, DI. Nosocomial methicillin-resistant and methicillin-susceptible Staphylococcus aureus primary bacteremia: at what costs? Infect Control Hosp Epidemiol 1999;20:408411.
11.Lodise, TP, McKinnon, PS. Clinical and economic impact of methicillin resistance in patients with Staphylococcus aureus bacteremia. Diagn Microbiol Infect Dis 2005;52:113122.
12.Shorr, AF, Tabak, YP, Gupta, V, Johannes, RS, Liu, LZ, Kollef, MH. Morbidity and cost burden of methicillin-resistant Staphylococcus aureus in early onset ventilator-associated pneumonia. Crit Care 2006;10:R97.
13.McHugh, CG, Riley, LW. Risk factors and costs associated with methicillin-resistant Staphylococcus aureus bloodstream infections. Infect Control Hosp Epidemiol 2004;25:425430.
14.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.
15.Soriano, A, Martinez, JA, Mensa, J, et al. Pathogenic significance of methicillin resistance for patients with Staphylococcus aureus bacteremia. Clin Infect Dis 2000;30:368373.
16.Garner, JS, Jarvis, WR, Emori, TG, Horan, TC, Hughes, JM. CDC definitions for nosocomial infections, 1988. Am J Infect Control 1988;16:128140.
17.McCabe, WR, Jackson, GG. Gram-negative bacteremia. Arch Intern Med 1962;110:8391.
18.Charlson, ME, Pompei, P, Ales, KL, MacKenzie, CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis 1987;40:373383.
19.Knaus, WA, Wagner, DP, Draper, EA, et al. The APACHE III prognostic system: risk prediction of hospital mortality for critically ill hospitalized adults. Chest 1991;100:16191636.
20.Rubin, DB, Thomas, N. Matching using estimated propensity scores: relating theory to practice. Biometrics 1996;52:249264.
21.Rosenbaum, PR, Rubin, D. The central role of the propensity score in observational studies for causal effects. Biometrika 1983;70:4155.
22.Rubin, DB. Using propensity scores to help design observational studies: application to the tobacco litigation. Health Services and Outcomes Research Methodology 2001;2:169188.
23.Kurth, T, Walker, AM, Glynn, RJ, et al. Results of multivariable logistic regression, propensity matching, propensity adjustment, and propensity-based weighting under conditions of nonuniform effect. Am J Epidemiol 2006;163:262270.
24.Austin, PC, Mamdani, MM. A comparison of propensity score methods: a case-study estimating the effectiveness of post-AMI statin use. Stat Med 2006;25:20842106.
25.Hosmer, D, Lemeshow, S. Applied logistic regression. 2nd ed. Somerset, NJ: John Wiley and Sons; 2000.
26.Menashe, G, Borer, A, Yagupsky, P, et al. Clinical significance and impact on mortality of extended-spectrum β lactamase-producing Enterobacteriaceae isolates in nosocomial bacteremia. Scand J Infect Dis 2001;33:188193.
27.Blot, SI, Vandewoude, KH, Hoste, EA, Colardyn, FA. Outcome and attributable mortality in critically 111 patients with bacteremia involving methicillin-susceptible and methicillin-resistant Staphylococcus aureus. Arch Intern Med 2002;162:22292235.
28.Shay, DK, Maloney, SA, Montecalvo, M, et al. Epidemiology and mortality risk of vancomycin-resistant enterococcal bloodstream infections. J Infect Dis 1995;172:9931000.
29.Cosgrove, SE, Carmeli, Y. The impact of antimicrobial resistance on health and economic outcomes. Clin Infect Dis 2003;36:14331437.
30.Blot, S, Depuydt, P, Vandewoude, K, De Bacquer, D. Measuring the impact of multidrug resistance in nosocomial infection. Curr Opin Infect Dis 2007;20:391396.
31.Lunceford, JK, Davidian, M. Stratification and weighting via the propensity score in estimation of causal treatment effects: a comparative study. Stat Med 2004;23:29372960.
32.Cosgrove, SE, Qi, Y, Kaye, KS, Harbarth, S, Karchmer, AW, Carmeli, Y. The impact of methicillin resistance in Staphylococcus aureus bacteremia on patient outcomes: mortality, length of stay, and hospital charges. Infect Control Hosp Epidemiol 2005;26:166174.
33.Chaix, C, Durand-Zaleski, I, Alberti, C, Brun-Buisson, C. Control of endemic methicillin-resistant Staphylococcus aureus: a cost-benefit analysis in an intensive care unit. JAMA 1999;282:17451751.
34.Selvey, LA, Whitby, M, Johnson, B. Nosocomial methicillin-resistant Staphylococcus aureus bacteremia: is it any worse than nosocomial meth-icillin-sensitive Staphylococcus aureus bacteremia? Infect Control Hosp Epidemiol 2000;21:645648.
35.Shorr, AF, Micek, ST, Kollef, MH. Inappropriate therapy for methicillin-resistant Staphylococcus aureus: resource utilization and cost implications. Crit Care Med 2008;36:23352340.
36.Khatib, R, Saeed, S, Sharma, M, Riederer, K, Fakih, MG, Johnson, LB. Impact of initial antibiotic choice and delayed appropriate treatment on the outcome of Staphylococcus aureus bacteremia. Eur J Clin Microbiol Infect Dis 2006;25:181185.
37.Klevens, RM, Edwards, JR, Tenover, FC, McDonald, LC, Horan, T, Gaynes, R. Changes in the epidemiology of methicillin-resistant Staphylococcus aureus in intensive care units in US hospitals, 1992-2003. Clin Infect Dis 2006;42:389391.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Infection Control & Hospital Epidemiology
  • ISSN: 0899-823X
  • EISSN: 1559-6834
  • URL: /core/journals/infection-control-and-hospital-epidemiology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed