USA: Antifungal Prescribing and Resistance

The high volume of topical antifungal prescribing could be feeding the spread and emergence of antifungal-resistant infections, suggests a study led by Centers for Disease Control and Prevention (CDC) researchers.

The study, published in Morbidity and Mortality Weekly Report, revealed that 6.5 million topical antifungal prescriptions valued at $231 million were filled for Medicare Part D beneficiaries in 2021, about half of which were written by high-volume prescribers. And many of these prescriptions could be inappropriate.

"In the setting of emerging antimicrobial resistance, these findings underscore the importance of expanding efforts to understand current prescribing practices while encouraging judicious prescribing by clinicians and providing patient education about proper use," the study authors wrote.

According to Kaitlin Benedict, National Center for Emerging and Zoonotic Infectious Diseases, CDC, and colleagues, findings are a concern because of the emergence and spread of antimicrobial-resistant superficial fungal infections like ringworm.

Recently, severe antimicrobial-resistant superficial fungal infections have been detected in the US; evaluating topical antifungal use is an initial step in developing strategies to prevent the global emergence and spread of these infections.

The CDC examined prescription volumes, costs, and rates for topical antifungals (including topical combination antifungal-corticosteroid medications). A comparison is drawn of total prescription volumes between higher-volume prescribers (top 10% of topical antifungal prescribers by volume) and lower-volume prescribers. During 2021, approximately 6.5 million topical antifungal prescriptions were filled (134 prescriptions per 1,000 beneficiaries), at a total cost of $231 million.

Key Findings

• During 2021, approximately 6.5 million topical antifungal prescriptions were filled (134 prescriptions per 1,000 beneficiaries), at a total cost of $231 million.
• Among 1,017,417 unique prescribers, 130,637 (12.8%) prescribed topical antifungals.
• Primary care physicians wrote the highest percentage of prescriptions (40.0%), followed by nurse practitioners or physician assistants (21.4%), dermatologists (17.6%), and podiatrists (14.1%).
• Higher-volume prescribers wrote 44.2% (2.9 million) of all prescriptions.

This study found that enough topical antifungal prescriptions were written for about one of every eight Medicare Part D beneficiaries in 2021, and 10% of antifungal prescribers prescribed nearly one-half of these medications.

The large volume of topical antifungal-corticosteroid and antifungal prescriptions among Medicare Part D beneficiaries in the setting of emerging resistant infections underscores the need to evaluate current practices of topical antifungal use.

"Health care providers should be judicious in prescribing topical antifungals and antifungal-corticosteroid medications for suspected superficial fungal infections, using testing when feasible to confirm diagnoses, and can educate patients about the correct use of topical antifungals and combination antifungal-corticosteroids," the researchers concluded.

Reference

Benedict K, Smith DJ, Chiller T, Lipner SR, Gold JA. Topical Antifungal Prescribing for Medicare Part D Beneficiaries — United States, 2021. MMWR Morb Mortal Wkly Rep 2024;73:1–5. DOI: http://dx.doi.org/10.15585/mmwr.mm7301a1