Four Drugs Comprise Half of All Inpatient Antimicrobial Treatment

Roughly half of all patients hospitalized between May 2011 and September 2011 received at least 1 antimicrobial drug, the results of a study published in JAMA suggest.

Given that antimicrobial drug use is the top risk factor for acquiring hard-to-treat pathogens, as well as the leading cause of adverse events in hospitals, researchers from the US Centers for Disease Control and Prevention (CDC) surveyed 11,282 patients at 183 acute care facilities across 10 states to determine the prevalence of inpatient antimicrobial drug use, the most common antimicrobial drugs used, and the motives behind their use.

At the time of the 1-day prevalence survey, 5635 patients (49.9%) were receiving 1 or more antimicrobial drugs, of whom 1840 (32.7%) were given 2 drugs, 682 (12.1%) were receiving 3 drugs, and 302 (5.4%) were given 4 or more drugs. The drugs were most commonly administered to treat infections (77.5%), which usually involved the lower respiratory tract, urinary tract, or skin and soft tissues.

Although the researchers observed 83 different drugs that were administered to treat infections in hospitalized patients, parenteral vancomycin, piperacillin­tazobactam, ceftriaxone, and levofloxacin comprised approximately 45% of all antimicrobial drug treatment and were the most common drugs for health care facility- and community-onset infections, as well as for patients outside of the emergency room.

The researchers attributed the high prevalence of vancomycin to the rise of methicillin-resistant Staphylococcus aureus (MRSA) in health care settings. Although the rates of community-associated MRSA infections have improved only slightly in recent years, a relatively low proportion of infections in the surveyed hospital settings were caused by MRSA or coagulase-negative staphylococci.

“Results from this prevalence survey…points to specific areas where interventions to improve antimicrobial use may be needed, such as vancomycin prescribing and respiratory infection treatment, supporting the CDC’s recommendation that every acute care hospital implement an antimicrobial stewardship program,” the study authors wrote. “To minimize patient harm and preserve effectiveness, it is imperative to critically examine and improve the ways in which antimicrobial drugs are used. Improving antimicrobial use in hospitals benefits individual patients and also contributes to reducing antimicrobial resistance nationally.”