Antibiotic Prophylaxis Prior to Dental Procedures Largely Unnecessary, Tied to Risks

Dental visits have been identified as ripe opportunities to implement antibiotic stewardship in order to cut down on the rising rate of unnecessary prescriptions.

Indeed, previous studies have shown that dentists prescribe 10% of outpatient antibiotics in the United States, a significant portion of which comprise prophylaxis prior to dental visits. What’s more, 80% of these prophylactic prescriptions have been found to be unnecessary.

A group of investigators from the University of Illinois set out to assess the risks of unnecessary antibiotic prophylaxis, according to a national health claims database. The study was presented at IDWeek 2019 and chosen by the Society for Healthcare Epidemiology of America as the featured oral abstract.

The retrospective cohort study included data from patients who visited the dentist between 2011 and 2015 and were linked to a medical and/or prescription claim. The research team defined unnecessary antibiotic prophylaxis as “antibiotic prophylaxis in patients who both did not undergo a procedure that manipulated the gingiva/tooth periapex and did not have an appropriate cardiac diagnosis.” Patients deemed to meet the unnecessary antibiotic prophylaxis criteria were included in the study and assessed for antibiotic-related adverse effects (AAE).

Investigators also considered patients with commercial dental insurance without a hospitalization or extra-oral infection 14 days prior to antibiotic prophylaxis (≤2 days supply dispensed within 7 days before a dental visit) for inclusion.

The primary end point was the cumulative incidence of any AAE within 14 days post-prescription (composite of allergy, anaphylaxis, Clostridioides difficile infection, or emergency department visit), with secondary end points including cumulative incidence of each individual AAE and the risk difference of the primary endpoint between amoxicillin and clindamycin.

A total of 168,420 dental visits included antibiotic prophylaxis, 136,177 (80%) of which were deemed unnecessary and, thus, included for analysis in the study. Unnecessary prescriptions were associated with AAE in 3.8% of cases, with emergency department visits (1.2%) and new allergies (2.9%) as the most frequent. Clindamycin was associated with more AAE than amoxicillin (risk difference 322.1 per 1000 person-years, 95% confidence interval: 238.5 - 405.8).

Study co-authors Alan E. Gross, PharmD, clinical assistant professor at the University of Illinois, and Katie J. Suda, PharmD, MS, research clinical scientist at Hines VA Hospital and University of Illinois at Chicago College of Pharmacy, discussed their research on the harms of unnecessary dental antibiotic prophylaxis at with Contagion® at IDWeek 2019.

“Even though antibiotic prophylaxis is prescribed for a short duration (≤2 days), it is not without risk. Since most AAE are diagnosed in medical settings, dentists may not be aware of these adverse effects,” investigators concluded. “These data provide further impetus to decrease unnecessary prescribing of antibiotic prophylaxis prior to dental procedures.”

The study, Serious Antibiotic-Related Adverse Effects Following Unnecessary Dental Prophylaxis in the United States, was presented in an oral abstract session on Friday, October 4, 2019, at IDWeek in Washington, DC.