Antibiotics are more often prescribed during ambulatory visits involving a nurse practitioner or a physician assistant than during those solely attended by a physician, according to a recently published CDC study.
As such, interventions specifically targeting these health care providers could improve the effectiveness of antibiotic stewardship programs, according to Lauri A. Hicks, DO, director of the CDC’s office of antibiotic stewardship, and colleagues.
“Most research assessing outpatient antibiotic prescribing has focused on physicians,” the researchers wrote. “Less is known about the prescribing practices of nurse practitioners (NPs) and physician assistants (PAs), who collectively represent more than one-quarter of the U.S. primary care workforce.”
Lauri A. Hicks
Hicks and colleagues reviewed data collected from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey between 1998 and 2011. They divided each recorded ambulatory visit by NP/PA involvement or noninvolvement, and identified trends in the frequency of NP/PA involvement and antibiotic prescription across settings. To account for potential biases due to case mix, the researchers also conducted a subanalysis of prescribing practices exclusively during visits occurring from 2006 to 2011 involving adult patients with acute respiratory tract infection and no comorbid illnesses.
Based on their sample of 1,301,474 visits, the researchers estimated that 6.3% (95% CI, 5.7-6.9) of the 1.13 billion annual ambulatory visits in the U.S. involved NPs or PAs. The prevalence of these health care providers increased in both ambulatory care settings (3.9% to 9.0%; P < .001) and EDs (5.1% to 17.9%; P < .001) from the beginning to the end of the study period.
The researchers found that 17% of visits between 2006 and 2011 involving NPs and PAs resulted in antibiotic prescriptions, as opposed to the 12% prescription rate of physician-only visits (P <.0001). This was also the case when restricting analysis to acute respiratory tract infection visits (61% vs. 54%; P < .001), and when the researchers controlled for patient- and practice-level characteristics (OR = 1.31; 95% CI, 1.19-1.43). There were no significant differences in prescription practices in regard to broad-spectrum antibiotics, as well as when comparing visits with PAs against those with NPs.
Hicks and colleagues pointed out a number of factors that could be contributing to these prescription trends, such as many antibiotic stewardship programs’ focus on physician behavior over the practices of NPs and PAs, and suggested further research and interventions targeting prescription patterns in these groups.
“Future efforts should seek to understand the differences in antibiotic prescribing observed in the present study, including the assessment of workplace and patient communication dynamics which may contribute to excess antibiotic prescribing,” they wrote. “As the proportion of outpatient visits involving NPs and PAs continues to increase, interventions to reduce inappropriate antibiotic use in ambulatory care should target these providers in addition to physicians.” – by Dave Muoio