Dr. Michael Ardern-Jones discusses a large study that suggests venous thromboembolism risk is significantly higher among those with atopic dermatitis and how this finding might impact care.
Michael Ardern-Jones, BSc, MBBS, MRCP, DPhil, FRCP, Professor of Dermatology, University of Southampton, Southampton, United Kingdom
“It has been known for quite a long time that people with inflammatory diseases have an increased risk of venous thromboembolism, with the classic disease being rheumatoid arthritis. But there hasn’t been a clear finding of whether this risk is also relevant in people with inflammatory skin diseases, such as atopic dermatitis,” said Michael Ardern-Jones, BSc, MBBS, MRCP, DPhil, FRCP, who presented “Atopic Dermatitis Is Associated With an Increased Risk of Venous Thromboembolism: UK Population-Based Cohort Study” at the European Academy of Dermatology and Venereology (EADV) Congress in Milan, Italy.
According to Dr. Ardern-Jones, he and coauthors accessed the National Health Service’s General Practice (GP) Data Hub, a large database of millions of UK patients who consented to sharing their electronic medical record data for research studies.
“We [looked at] patients with atopic dermatitis for a period of 10 years and matched them to controls without atopic dermatitis. One of the neat things about this study is that we could make the controls super matched—not only by age and sex but also by geographic location to minimize risk of bias.”
The researchers studied 150,000 patients with atopic dermatitis, analyzing the impact of factors that modify venous thromboembolism risk, including age, sex, obesity, smoking, alcohol, and ethnicity, said Dr. Ardern-Jones.
“We found a small but definitive increased risk of venous thromboembolism in atopic dermatitis. The increased risk can be assessed from the adjusted hazard ratio of 1.17 overall (17% increase), which was a highly significant finding. What we found and were surprised by was this risk was different for deep vein thrombosis which was 30% more common in atopic dermatitis, but there was no increased risk of pulmonary embolism.”
Interestingly, the increased risk was not strongly linked with disease severity, according to Dr. Ardern-Jones.
“We saw an increased risk of venous thromboembolism across all the spectrum of atopic dermatitis severities—mild, moderate, and severe. Numerically we saw a slightly higher risk in severe cases, but it wasn’t significant.”
However, the severe atopic dermatitis arm of the study might have been underestimated, given the researchers categorized those with severe disease based on if they had been selected for phototherapy or systemic treatment for atopic dermatitis, said Dr. Ardern-Jones.
“Often in the UK, systemic treatment for atopic dermatitis is prescribed in hospital, so it’s possible that some patients with severe disease were not labeled as such because the prescribing was done off the GP database.”
Venous thromboembolism risk increased in atopic dermatitis patients who were obese, but even in the non-obese group, there was an increased risk of venous thromboembolism in patients with atopic dermatitis compared to controls, he said.
“We also looked at age and saw clearly, as you’d expect, an increased risk with increasing age. At a young age, under 45, we lost statistical significance of increased risk of venous thromboembolism but numerically it was still slightly increased… in patients with atopic dermatitis.”
“There are limitations to this work in that we didn’t see patients ourselves and we relied on electronic medical records. And as I mentioned, the severity of atopic dermatitis may not have been perfectly recorded or represented.”
Practical Application
This is important information for dermatologists, said Dr. Ardern-Jones.
“…it’s a finding that we weren’t previously particularly aware of, so it’s important to discuss the risk of venous thromboembolism with our patients.”
That includes talking with patients who have other risk factors for venous thromboembolism, such as obesity or smoking, as well as others who are about to embark on long-distance travel, he said.
The study’s findings also are important when considering atopic dermatitis treatments that might increase venous thromboembolism risk, he said.
“We need to potentially target these new treatments to the groups that we think have the lower risk of venous thromboembolism in the first place until we’ve fully explored that issue.”
Disclosures: Dr. Ardern-Joneshas been a consultant/speaker/PI for Almirall, AbbVie, Amgen, Galderma, Janssen, Leo, Lilly, Pfizer, Sanofi Genzyme, Ducentis, Heptares, and Unilever. The research presented was funded by Pfizer.
