PORTLAND, ORE. – About 10 years ago when Arash Mostaghimi, MD, MPA, MPH, became an attending physician at Brigham and Women’s Hospital, Boston, he noticed that some of his dermatology colleagues checked the potassium levels religiously in their female patients taking spironolactone, while others never did.
“It led to this question: Dr. Mostaghimi, director of the dermatology inpatient service at Brigham and Women’s, said at the annual meeting of the Pacific Dermatologic Association.
To find out, he and his colleagues reviewed 1,802 serum potassium measurements in a study of healthy young women with no known health conditions who were taking spironolactone, published in 2015. They discovered that 13 of those tests suggested mild hyperkalemia, defined as a level greater than 5.0 mEq/L. Of these, six were rechecked and were normal; no action was taken in the other seven patients.
Dr. Arash Mostaghimi
“This led us to conclude that we spent $78,000 at our institution on testing that did not appear to yield clinically significant information for these patients, and that routine potassium monitoring is unnecessary for most women taking spironolactone for acne,” he said. Their findings have been validated “in many cohorts of data,” he added.
The study serves as an example of efforts dermatologists can take to curb unnecessary costs within the field to be “appropriate stewards of resources,” he continued. “We have to think about the ratio of benefit over cost. It’s not just about the cost, it’s about what you’re getting for the amount of money that you’re spending. The idea of this is not restricting or not giving people medications or access to things that they need. The idea is to do it in a thoughtful way that works across the population.”
Value thresholds
Determining the value thresholds of a particular medicine or procedure is also essential to good dermatology practice. To illustrate, Dr. Mostaghimi cited a prospective cohort study that compared treatment patterns and clinical outcomes in 1,536 consecutive patients with nonmelanoma skin cancer (NMSC) with and without limited life expectancy. More than two-thirds of the NMSCs (69%) were treated surgically. After adjusting for tumor and patient characteristics, the researchers found that 43% of patients with low life expectancy died within 5 years, but not from NMSC.
“Does that mean we shouldn’t do surgery for NMSC patients with low life expectancy?” he asked. “Should we do it less? Should we let the patients decide? It’s complicated. As a society, we have to decide what’s worth doing and what’s not worth doing,” he said. “What about old diseases with new treatments, like alopecia areata? Is alopecia areata a cosmetic condition? Dermatologists and patients wouldn’t classify it that way, but many insurers do. How do you negotiate that?”
In 2013, the American Academy of Dermatology identified 10 evidence-based recommendations that can support conversations between patients and dermatologists about treatments, tests, and procedures that may not be necessary. One of the recommendations was not to prescribe oral antifungal therapy for suspected nail fungus without confirmation of fungal infection.
“If a clinician thinks a patient has onychomycosis, he or she is usually right,” Dr. Mostaghimi said. “But what’s the added cost/benefit of performing a KOH followed by PAS testing if negative or performing a PAS test directly versus just treating the patient?”
In 2006, he and his colleagues published the results of a decision analysis to address these questions. They determined that the costs of testing to avoid one case of clinically apparent liver injury with terbinafine treatment was $18.2-$43.7 million for the KOH screening pathway and $37.6 to $90.2 million for the PAS testing pathway.
“Is that worth it?” he asked. “Would we get more value for spending the money elsewhere? In this case, the answer is most likely yes.”