Antibiotic Use: Still Room for Improvement

Antibiotic Use: Still Room for Improvement

Abstract & Commentary

By Martin S. Lipsky, MD

Adjunct Professor, Institute on Aging, School of Community Health, Portland State University; Dean Emeritus, University of Illinois College of Medicine, Rockford

Dr. Lipsky is a retained consultant for Health Solutions & Strategies.

Synopsis: Broad-spectrum antibiotics constitute the majority
of antibiotic use in ambulatory care. Despite multiple guidelines promoting more judicious use of antibiotics, about one in four prescriptions were for conditions in which antibiotics are rarely indicated.

Source: Shapiro DJ, et. al. Antibiotic prescribing for adults in ambulatory care in the USA, 2007-2009. J Antimicrob Chemother 2013; Jul 25. doi:10.1093/jac/dkt301. [Epub ahead of print.]

Antibiotics are one of the most commonly prescribed medications in the United States. About 10% of office visits result in an antibiotic prescription. Historically, many of these scripts were used for viral illnesses, a condition for which antibiotics are not indicated. To address antibiotic overuse, several professional organizations have published guidelines promoting judicious use of antibiotics. Many of these address the use of antibiotics for acute respiratory infection, which has traditionally been an illness that often triggers inappropriate prescribing. While there may be some modest decline in overall antibiotic use,1 there still appears to be persistent prescribing for conditions like bronchitis where antibiotics offer little benefit.

In this study, Shapiro and colleagues sought to determine the current pattern of antibiotic use and describe conditions for which antibiotics are prescribed. They also sought to identify factors associated with broad-spectrum antibiotic use.

The authors used 2007-2009 data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Care Survey to examine prescribing patterns for patients over 18 years of age visiting an ambulatory care setting. Visits were grouped into the following categories: respiratory conditions, skin/mucosal conditions, including soft tissue infections, genitourinary (GU) conditions, gastrointestinal (GI) conditions, miscellaneous infections, surgical/ post-surgical visits, and all other conditions and diagnoses. Respiratory conditions were subdivided into acute respiratory tract infections (ARTIs) for which antibiotics are potentially indicated such as pneumonia, ARTIs for which antibiotics are rarely indicated such as laryngitis, and respiratory conditions that rarely merit antibiotic treatment such as asthma. Similar divisions were made for GU and GI visits. The study also classified antibiotics as either broad spectrum or narrow spectrum. Broad-spectrum drugs included extended-spectrum penicillin, such as amoxicillin/clavulinic acid, second- to fourth-generation cephalosporin, macrolides, quinolones, and lincomycin injections.

The authors found that 10%, or about 100 million ambulatory visits, resulted in an antibiotic prescription. The most commonly used antibiotics were quinolones (25% of prescriptions), macrolides (20%), and aminopenicillins (12%). Antibiotics were most commonly prescribed for respiratory conditions (41% of all antibiotic prescriptions) and urinary tract infections (9%). Using a logistic regression model, broad-spectrum antibiotics were more likely to be prescribed than narrower spectrum ones for respiratory infections, including conditions such as bronchitis for which they are rarely indicated, at emergency department (ED) visits, and for patients older than 60 years of age. The authors estimated that more than 25% of the broad-spectrum antibiotics were given for conditions where antibiotics are rarely indicated.

COMMENTARY

It would appear from this study that the battle against antibiotic overuse is far from over. While overall use might be declining marginally, a concern is that the use of broad-spectrum antibiotics is increasing. Unnecessary scripts add expense and contribute to resistance. Although these drugs are typically well tolerated in the outpatient setting, given the millions of patients taking them, even if only a small percentage of patients have a significant side effect, overprescribing results in a significant burden on the nation’s health.

Another recent study also affirms Shapiro et al’s findings that antibiotic overuse is still a major problem. Barnett and Linder found that antibiotics were prescribed at 60% of all ED visits for sore throats, even though only about 10% of these infections are bacterial.2

While physicians may know that antibiotics are unnecessary, they still seem willing to write the prescriptions. Likely reasons include patient pressure and expectations. It is often easier to prescribe an antibiotic than to take the time to explain why they do not work for an illness. Patients may interpret not receiving an antibiotic for bad bronchitis as the doctor failing to recognize how sick they are rather than the medicine will not help the condition. One helpful strategy may be to acknowledge upfront how badly a patient is feeling and that the reason for not giving an antibiotic is not because the patient is not ill but because it will not help. In working with medical students and residents, I would often overhear attending physicians tell a trainee that antibiotics were probably not indicated for the patient but that they were going to prescribe them because they either wanted to be on the safe side or because the patient pressured them to do so. This study reaffirms that we need to end our practice of telling students to do as I say not as I do but instead to be a role model for the judicious use of these often overprescribed medications.

References

1. Steinman MA, et al. Changing use of antibiotics in community-based outpatient practice, 1991-1999. Ann Intern Med 2003;138:525-533.
2. Barnett ML, Linder JA. Antibiotic prescribing to adults with sore throat in the United Sates, 1997-2010. JAMA Intern Med 2013; Oct 3. doi: 10.1001/jamainternmed.2013.11673. [Epub ahead of print.]