Table 1.

Review of prior studies that have examined the relationship between antimicrobial exposure and MDRO acquisition in the long-term care setting

Reference No.	First Author, Year	Location	Population	No. of Sites	No. of Participants	Defining Antimicrobial Exposure	Timing of Swabs	Definition of MDRO Acquisition	Study Design	Findings
15	Min, 2015	United States	Nursing home residents	15	111	Dichotomous 30 days prior during follow-up	Monthly until discharge or 12 months	First positive culture; any of Methicillin-resistant Staphylococcus aureus , antibiotic-resistant gram negative bacteria, or Vancomycin-resistant enterococci	Prospective cohort	In unadjusted analysis, antibiotic use in the past 30 days significantly associated with time to initial Vancomycin-resistant enterococci acquisition; no significant association in multivariable analysis
13	Couderc, 2014	France	Neurologic patients	4	76 cases; 207 controls; 112 sensitive controls	Dichotomous before admission and after admission	Weekly for 13 weeks	First positive culture; Methicillin-resistant Staphylococcus aureus	Nested case-case-control	Fluoroquinolone use significantly associated with Methicillin-resistant Staphylococcus aureus acquisition
12	Han, 2014	United States	Long-term care facility residents	3	120	Dichotomous 30 days prior to enrollment and during follow-up (time-varying)	Approximately every two weeks until recovery or up to 12 months or discharge or death	First positive culture; Fluoroquinolone-resistant E. coli	Prospective cohort	Amoxicillin-clavulanate use during follow-up significantly associated with Fluoroquinolone-resistant E. coli acquisition
11	Olofsson, 2013	Sweden	Nursing home residents	11	268	In the 180 days preceding sampling	Study entry	Positive culture; E. coli	Cross-sectional	Antimicrobial use significantly associated with antimicrobial-resistant E. coli
10	Stone, 2012	United States	Long-term care facility residents	3	254	Dichotomous in the 3 months before study and during study	Weekly 3 times during first month followed by monthly for 5 months	>1 positive culture and no subsequent negative cultures; Methicillin-resistant Staphylococcus aureus	Prospective cohort	Systemic antimicrobial use during study significantly associated with Methicillin-resistant Staphylococcus aureus acquisition
9	Fisch, 2012	United States	Skilled nursing facility patients	15	82	Dichotomous any use prior to colonization	Monthly swabs for up to 3 months	Any positive culture; Any new of Methicillin-resistant Staphylococcus aureus, Vancomycin-resistant enterococci, Ciprofloxacin-resistant, or Ceftazidime-resistant	Prospective cohort	Antimicrobial use prior to colonization not significantly associated with acquisition
8	Ray, 2010	United States	Long-term acute care hospital patients	1	13 cases; 27 controls	Dichotomous intravenous antibiotics on admission	Routine clinical care and point prevalence surveillance cultures	Any positive culture; Acinetobacter baumannii	Case-control	Intravenous antibiotics on admission significantly associated with Acinetobacter baumannii acquisition
7	O’Fallon, 2010	United States	Long-term care facility residents	1	29 cases; 29 controls	Dichotomous during interval between baseline culture and follow-up culture	Baseline and every 4 months for up to 12 months of follow-up	Any positive culture; multi-drug resistant gram negative bacteria	Nested case-control	Antimicrobial use during the study significantly associated with multi-drug resistant gram negative bacteria acquisition
6	Manzur, 2010	Spain	Long-term care facility residents	9	196	Dichotomous any exposure during follow-up	Every 6 months for up to 18 months	Any positive culture; Methicillin-resistant Staphylococcus aureus	Prospective cohort	Antimicrobial use during follow-up significantly associated with Methicillin-resistant Staphylococcus aureus acquisition
5	Maslow, 2005	United States	Long-term care facility residents	1	49	Dichotomous use in the 3, 6, 9, and 12 months before study entry	At study entry	Positive culture; Fluoroquinolone-resistant E. coli	Cross-sectional	Fluoroquinolone use within the past 12 months significantly associated with Fluoroquinolone-resistant E. coli acquisition
4	Nazir, 2004	United States	Long-term care facility residents	1	28 cases matched 4:1 controls to cases	Dichotomous any antimicrobial use and approximate annual days of therapy derived from no. of prescriptions	Routine clinical cultures	Any positive culture; Levofloxacin-resistant H. influenzae	Case-control	Any Levofloxacin use significantly associated with Levofloxacin-resistant H. influenza acquisition
3	Vasquez, 2000	United States	Acute care patients, long-term care facility residents, and nursing home residents	1	96 cases; 96 controls	Systemic exposure within the previous 30 days	Routine clinical cultures	Any positive culture; Mupirocin-resistant Methicillin-resistant Staphylococcus aureus	Case-control	Mupirocin use not significantly associated with Mupirocin-resistant Methicillin-resistant Staphylococcus aureus acquisition