In an interview, Dr. Avram said he had made a concerted effort to alert the public of the side effect as soon as he learned about it from Zeltiq in 2012.
“The first thing we did was we published it out, so there could be as much awareness of it as possible,” he said.
As to the gap between the company’s findings and the article’s publication, Dr. Avram said it had taken time to analyze the data, write the report and undergo the journal’s review process. In the interim, he said, he presented information about P.A.H. at medical conferences.
Dr. Anderson did not respond to requests for comment.
A War of Numbers
When Dr. Avram and Dr. Anderson published information on the side effect in 2014, they estimated that its prevalence was 0.005 percent, or about 1 in every 20,000 treatments.
The previous year, however, a doctor advising Zeltiq had estimated the risk to be more than double that number — 0.011 percent, or about 1 in every 10,000 treatments — according to a document sent to company executives, a copy of which was obtained by The Times.
More discrepancies in data would follow, in part because the company and its consultants used the number of treatments to calculate the risk of P.A.H., while physicians observing the side effect usually used the number of patients.
For example, if two patients each underwent 10 sessions of CoolSculpting and one developed P.A.H., the company’s method would yield an incidence of 1 in 20 treatments, or 5 percent. Calculating the frequency by patient, however, would produce an incidence of 1 in 2 patients, or 50 percent.