Cost effect of managing methicillin-resistant Staphylococcus aureus in a long-term care facility

The purpose of this study was to measure the total consumption of resources involved in the care of a long-term care facility (LTCF) resident infected with methicillin-resistant Staphylococcus aureus (MRSA).

A retrospective cohort study.

A 375-bed LTCF that provides two levels of care.

Ninety LTCF residents infected with Staphylococcus aureus (mean age +/- standard deviation for methicillin-sensitive Staphylococcus aureus (MSSA) patients = 85 +/- 8.8, for MRSA patients = 82 +/- 9.5, P =.127; 49 MSSA and 41 MRSA patients). Inclusion criteria consisted of identification of a positive S. aureus culture in addition to symptoms/signs consistent with infection. Patients colonized with S. aureus were excluded.

A standardized data collection tool was used to conduct chart and database review throughout the defined infection period. The type of information collected included demographic, infection characterization, antibiotic regimen, resource assessment, and cost data. The cost data were further categorized into total pharmaceutical, infection management, physician care, nursing care, and total infection cost.

One hundred eleven cases were identified, with 90 cases eligible for evaluation. No difference in population demographics was noted between groups. A significantly higher number of patients in the MRSA group had an indwelling device (P <.001), pressure ulcer(s) (P =.028), or diabetes mellitus (P =.007). There was a significantly higher number of patients with congestive heart failure in the MSSA group (P =.047), but no difference existed in the primary infection site (P =.297) or the incidence of patients with more than two comorbidities (P =.509). The infection characterization variables included were also similar between groups. The most prevalent infection site was the urinary tract (48%) followed by skin/skin structure (38%). Because the majority of patients (82%) developed infection at least 30 days after their LTCF admission, the infections may be considered to have been largely LTCF acquired. The median infection management cost of an MRSA infection was six times greater than that of a MSSA infection (P <.001), whereas the median associated nursing care cost was two times greater (P =.001). The median overall infection cost associated with MRSA was 1.95 times greater than that of MSSA (median (range): MSSA 1,332 US dollars (268-7,265 US dollars) vs MRSA 2,607 US dollars (849-8,895 US dollars), P <.001). Nursing care cost constituted the major portion of the overall infection cost in both groups (MSSA 51%, MRSA 48%). Evaluation of antimicrobial management revealed that infected residents were treated with a wide array of combination therapies (65% of patients received combination therapy).

The management of a resident infected with MRSA was much more costly to the LTCF than that of an MSSA-infected patient. The general care of the patient and not the specific antibiotic regimen influenced the large difference in cost between groups. The approach to the antibiotic management of these patients was variable. A more streamlined approach to infection management that facilitates a faster cure rate may dramatically lower resource consumption and improve patient outcomes.