How Often is Potassium Monitoring for Spironolactone Necessary?

Although a growing body of evidence suggests spironolactone poses minimal risk for hyperkalemia and new guidance statements call for clinicians to move away from this practice, potassium monitoring of healthy, young women with acne who are treated with this acne therapy remains relatively common, study results published in JAMA Dermatology suggest.

In this retrospective cohort study, a small team of US-based researchers analyzed data of 108,547 healthy women aged 12 to 45 years (mean age, 30.7 years of age) who were treated for acne with spironolactone from 2008 to 2019. Deidentified data were obtained from the Optum Clinformatics Data Mart database.

The main outcome of the analysis was the percentage of patients who received a baseline potassium level test and the percentage of women who underwent potassium monitoring in the first 180 days of spironolactone initiation. The investigators also compared the clinicians who prescribed 5 or more spironolactone courses, the percentage of clinicians who ordered a baseline potassium test or monitoring, and the percentage of clinicians who reported they always monitored potassium from 2008 to 2015 vs from 2016 to 2018.

Overall, the mean duration of a course of spironolactone was 159 days. The percentage of women who underwent monitoring of their potassium levels under the direction of dermatologists within 180 days of initiating spironolactone decreased from 41.4% in 2008 to 38.5% in 2018. Among internists the percentage of women who underwent potassium monitoring decreased from 39.7% to 37.7% during this time.

In contrast, the investigators noted that there was an increase in potassium monitoring from 2008 to 2018 under advanced practice clinicians, such as nurse practitioners and physician assistants, from 71.4% to 75.4%, respectively.

From 2008 to 2015 and from 2016 to 2018, there was a respective 10.6% and 4.2% decrease in the percentage of dermatologists who always monitored potassium levels in women who started spironolactone for acne. No significant difference was observed in the percentage of internists who always monitored potassium levels from 2008 to 2015 (15.8%) vs from 2016 to 2018 (17.7%; P =.37).

In an analysis adjusted for patient age, each additional 10 total spironolactone courses prescribed by a clinician was significantly associated with decreased odds of all clinicians always monitoring potassium (odds ratio [OR], 0.65; 95% CI, 0.53-0.79) and in dermatologists (OR, 0.57; 95% CI, 0.46-0.71).

Limitations of this study included its retrospective design as well as the lack of adjustment for baseline potassium level tests that may have been ordered before an acne encounter. The investigators suggest the latter limitation could have underestimated testing the true incidence baseline potassium testing incidence.

The researchers concluded that there currently exists “a need for future implementation and dissemination research to understand underlying factors for this variation and to develop strategies to address this practice gap.”

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Barbieri JS, Margolis DJ, Mostaghimi A. Temporal trends and clinician variability in potassium monitoring of healthy young women treated for acne with spironolactone. Published online January 27, 2021. JAMA Dermatol. doi:10.1001/jamadermatol.2020.5468