Infection management and multidrug-resistant organisms in nursing home residents with advanced dementia

Abstract

Importance: Infection management in advanced dementia has important implications for (1) providing high-quality care to patients near the end of life and (2) minimizing the public health threat posed by the emergence of multidrug-resistant organisms (MDROs).

Design, setting, and participants: Prospective cohort study of 362 residents with advanced dementia and their health care proxies in 35 Boston area nursing homes for up to 12 months.

Main outcomes and measures: Data were collected to characterize suspected infections, use of antimicrobial agents (antimicrobials), clinician counseling of proxies about antimicrobials, proxy preference for the goals of care, and colonization with MDROs (methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, and multidrug-resistant gram-negative bacteria). Main outcomes were (1) proportion of suspected infections treated with antimicrobials that met minimum clinical criteria to initiate antimicrobial treatment based on consensus guidelines and (2) cumulative incidence of MDRO acquisition among noncolonized residents at baseline.

Results: The cohort experienced 496 suspected infections; 72.4% were treated with antimicrobials, most commonly quinolones (39.8%) and third- or fourth-generation cephalosporins (20.6%). At baseline, 94.8% of proxies stated that comfort was the primary goal of care, and 37.8% received counseling from clinicians about antimicrobial use. Minimum clinical criteria supporting antimicrobial treatment initiation were present for 44.0% of treated episodes and were more likely when proxies were counseled about antimicrobial use (adjusted odds ratio, 1.42; 95% CI, 1.08-1.86) and when the infection source was not the urinary tract (referent). Among noncolonized residents at baseline, the cumulative incidence of MDRO acquisition at 1 year was 48%. Acquisition was associated with exposure (>1 day) to quinolones (adjusted hazard ratio [AHR], 1.89; 95% CI, 1.28-2.81) and third- or fourth-generation cephalosporins (AHR, 1.57; 95% CI, 1.04-2.40).

Conclusions and relevance: Antimicrobials are prescribed for most suspected infections in advanced dementia but often in the absence of minimum clinical criteria to support their use. Colonization with MDROs is extensive in nursing homes and is associated with exposure to quinolones and third- and fourth-generation cephalosporins. A more judicious approach to infection management may reduce unnecessary treatment in these frail patients, who most often have comfort as their primary goal of care, and the public health threat of MDRO emergence.

Figure

Cumulative Incidence Rates of Resident Acquisition of Drug-Resistant Organisms During the Study Period MDRGNB indicates multidrug-resistant gram-negative bacteria; MDRO indicates multidrug-resistant organism; MRSA, methicillin-resistant Staphylococcus aureus; VRE, vancomycin-resistant enterococci. “Any MDRO” includes MDGRN, MRSA, or VRE. All residents were free of all 3 types of MDROs at baseline. Only 2 residents acquired VRE over the 12 months of the study.