Functional disability and nursing resource use are predictive of antimicrobial resistance in nursing homes

To use a simple measure of activities of daily living, wounds, and indwelling devices (urinary catheter, feeding tube) to predict prevalent, new, and intermittent multidrug-resistant organism (MDRO) acquisition in nursing home (NH) residents.

Secondary analysis, prospective cohort study.

Southeast Michigan NHs (n = 15).

NH residents (N = 111, mean age 81) with two or more monthly visits (729 total).

Monthly microbiological surveillance for MDROs from multiple anatomic sites from enrollment until discharge or 1 year. The Arling scale, previously developed as a measure of NH residents' need (time-intensity) for nursing resources, was used to predict prevalent and time to new or intermittent acquisition (months) of methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and antibiotic-resistant gram-negative bacteria (R-GNB) colonization using multiple-failure accelerated time-factor survival analysis, controlling for comorbidity, hospitalization, and antibiotic use in the prior month.

One-fifth of participants had a wound, and one-third had a device. There were 60 acquisitions of MRSA, 56 of R-GNB, and 15 of VRE. Expected time to acquisition was less than 1 year for MRSA (median 6.7 months) and R-GNB (median 4.5 months) and more than 1 year for VRE (median 40 months). Arling score was associated with earlier new MRSA and VRE acquisition. A resident with only mild functional impairment and no device or wound would be expected to acquire MRSA in 20 months, versus 5 months for someone needing the most-intense nursing contact.

MDRO acquisition is common in community NHs. Need for nursing care predicts new MDRO acquisition in NHs, suggesting potential mechanisms for MDRO acquisition and strategies for future interventions for high-risk individuals (e.g., enhanced barrier precautions).