Is Your Fat Freezing Result Reversed? What you should Know About Paradoxical Adipose Hyperplasia (PAH)

Understanding Paradoxical Adipose Hyperplasia (PAH)

Cryolipolysis, or "fat freezing," was initially US FDA-cleared (by then company Zeltiq) in 2010 for treatment of fat deposits of the flanks, and subsequently received US FDA clearance for other anatomical locations. Over the past several years, there have been increasing published reports and physician discussion regarding Paradoxical Adipose Hyperplasia (PAH) post-cryolipolysis, previously identified as a "rare" adverse effect.

Recent literature suggests that PAH is underreported, and in some studies the incidence of PAH can be as high as 0.67% (1,2) 

A few years ago, Celebrity supermodel Linda Evangelista filed a lawsuit against the Zeltiq corporation after revealing she'd been out of the spotlight after being diagnosed with PAH, which she attributed to several Zeltiq CoolSculpting sessions. (3) The media attention caused many to come forward with their adverse reactions or events with their fat freezing treatments. (4)

Causes – why does it happen?

Paradoxical adipose hyperplasia (PAH) is a rare and somewhat ironic condition that can happen after undergoing CoolSculpting treatments – a popular non-surgical fat reduction procedure that freezes fat cells that are later flushed out of the body naturally. With PAH, instead of shrinking, the fat cells in the treated area grow larger, causing noticeable, firm masses under the skin. Recent trends also suggest that PAH is not just limited to Coolsculpting treatments, but from any fat-freezing treatment type of device.

While there is no known scientific cause of PAH, some theories are shared in the literature. One of the most popular theories cites that some fat cells are resistant to the cold temperatures, and because they survive, they cause the body to react in a way that creates more of these cold-resistant fat cells. The body may overcompensate cell reproduction, resulting in excess fatty deposits. A second possibility is the body’s reaction to the suction component of cryolipolysis, where the negative pressure encourages certain types of fat cells to grow.

Are there any risk factors? How do I know if I am at risk of PAH?

There are no identifiable risk factors for PAH. Based on case series in the literature, there is a higher incidence of males affected with PAH, and affected areas tend to be the flanks and the lower abdomen.

Identifying if I had suffered from PAH – what are some of the symptoms/signs to look out for

Some of the telltale signs & symptoms of PAH include:

1. Hard, rubbery swelling of the subcutaneous (fat) tissue, usually within the specific area of fat freezing treatment (i.e. in the shape of the applicator)
2. This growth or increase in fat often happens gradually, usually beginning months after the fat freezing treatments and persists for years after.
3. The unusual growth or increase in fat may result in a visible increase in size of the affected area, and a change in the texture/consistency of the skin. These can sometimes be sensitive or even painful.
4. Whilst it is not uncommon to have transient swelling after fat freezing, patients with PAH may feel that they have persistent hard swelling that refuses to go away, even after a long time.
5. Often, the treatment clinics may recommend massages or other treatments to help alleviate the symptoms, but to no avail.
6. You may be told that the unusual fat bulge is also related to weight gain, which is usually not the case.

Treatment Options for PAH – what should I do?

1. It is advisable to return to the clinic you visited to report the adverse event. For Coolsculpting treatments (previously Zeltiq, now Abbvie), getting your clinic to report this case back to the local distributor would be helpful, as the parent company may offer financial assistance for correction of your PAH deformities. (4)
2. Seek advice from your Plastic Surgeon: they would be able to advise what are the types of treatment which would be useful in correcting PAH.

Seeking help from your Plastic Surgeon is Crucial

The most common surgery to correct PAH is liposuction. This procedure involves removing the excess fat cells that have formed in the treatment area by suctioning them through a fine bore cannula. Although traditional liposuction can be effective, the ideal option is typically ultrasound-assisted liposuction, which involves the use of ultrasound waves to break up the excess fat cells. When PAH occurs around the abdomen, a tummy tuck procedure may also be required to fully reverse the complication. Typically, patients are advised to wait several months to undergo corrective surgery for PAH, as that time allows the tissue to soften.

References

1. Cox EA, Nichols DS, Riklan JE, Pomputius A, Mehta SD, Mast BA, Furnas H, Canales F, Sorice-Virk S. Characteristics and Treatment of Patients Diagnosed With Paradoxical Adipose Hyperplasia After Cryolipolysis: A Case Series and Scoping Review. Aesthet Surg J. 2022 Dec 14;42(12):NP763-NP774. doi: 10.1093/asj/sjac219. PMID: 35961054.
2. Nikolis A, Enright KM. A Multicenter Evaluation of Paradoxical Adipose Hyperplasia Following Cryolipolysis for Fat Reduction and Body Contouring: A Review of 8658 Cycles in 2114 Patients. Aesthet Surg J. 2021 Jul 14;41(8):932-941. doi: 10.1093/asj/sjaa310. PMID: 33216910; PMCID: PMC8279305.
3. https://www.usatoday.com/story/entertainment/celebrities/2022/07/20/linda-evangelista-settles-coolsculpting-lawsuit-returns-modeling-fendi/10104808002/
4. https://www.nytimes.com/2023/04/16/style/coolsculpting-side-effect-risks.html