A comparison of costs and hospital length of stay associated with intravenous/oral linezolid or intravenous vancomycin treatment of complicated skin and soft-tissue infections caused by suspected or confirmed methicillin-resistant Staphylococcus aureus in elderly US patients.
OBJECTIVE
This study compared the costs and hospital length of stay (LOS) and duration of intravenous therapy associated with intravenous/oral linezolid or intravenous vancomycin treatment of complicated skin and soft-tissue infections (cSSTIs) caused by suspected or confirmed methicillin-resistant Staphylococcus aureus (MRSA) in elderly US patients.


METHODS
Data were obtained from elderly (>or=65 years) US patients participating in a multinational randomized trial of hospitalized cSSTI patients treated with linezolid or vancomycin. Costs (hospital and total) from the provider perspective were estimated for intent-to-treat (ITT) patients (ie, all those receiving >or=1 dose) using national 2003 costs (ward, medication, intravenous administration). LOS for inpatient care, duration of intravenous linezolid and vancomycin therapy (ITT and MRSA groups), and cure rates were evaluated.


RESULTS
Of 717 enrolled subjects, 163 (23%) were elderly (87 linezolid, 76 vancomycin), with no significant differences in demographic characteristics between the linezolid and vancomycin groups. Mean hospitalization and total costs were lower with linezolid compared with vancomycin (hospitalization: US $4510 vs US $6478, P<0.001; total: US $6009 vs US $7329, P=0.03). Linezolid was associated with a 3.5-day reduction in LOS and a 9.5-day reduction in the duration of intravenous therapy compared with vancomycin in the ITT group (both, P<0.001). Cure rates were comparable between linezolid and vancomycin in both the ITT group (88.7% vs 81.4%, respectively) and the MRSA group (80.0% vs 71.4%). In multivariate analyses of the ITT group, linezolid patients were 57% less likely than vancomycin patients to have a LOS >7 days (odds ratio = 0.43; 95% CI, 0.21-0.87). Chronic renal failure, malnutrition, and a diagnosis of infected ulcer predicted an LOS >7 days.


CONCLUSIONS
In this analysis of data from elderly patients with cSSTI caused by suspected or confirmed MRSA, linezolid treatment was associated with reductions in the costs of care, LOS, and duration of intravenous treatment without affecting the clinical outcomes. Although the use of a subset of patients from a larger trial that did not focus on the elderly can be seen as a study limitation, the elderly represent an important population when evaluating health care resource use and costs.
McCollum
Marianne
M
University o f Colorado at Denver and Health Sciences Center, Denver, Colorado 80262, USA. marianne.mccollum@uchsc.edu
Sorensen
Sonja V
SV
Liu
Larry Z
LZ
D000081:Acetamides / Q000191:economics* / Q000627:therapeutic use; D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000191:economics / Q000627:therapeutic use; D005260:Female; D017048:Health Care Costs; D006760:Hospitalization / Q000191:economics; D006801:Humans; D007275:Injections, Intravenous; D007902:Length of Stay / Q000191:economics / Q000706:statistics & numerical data*; D000069349:Linezolid; D008297:Male; D016106:Methicillin Resistance; D023303:Oxazolidinones / Q000191:economics* / Q000627:therapeutic use; D018461:Soft Tissue Infections / Q000150:complications / Q000188:drug therapy* / Q000191:economics / Q000382:microbiology; D013207:Staphylococcal Skin Infections / Q000150:complications / Q000188:drug therapy* / Q000191:economics / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects / Q000302:isolation & purification; D014481:United States; D014640:Vancomycin / Q000191:economics* / Q000627:therapeutic use
D000081:Acetamides; D000900:Anti-Bacterial Agents; D023303:Oxazolidinones; D014640:Vancomycin; D000069349:Linezolid