Psoriasis may be linked to obsessive-compulsive disorder (OCD), according to a new study in the Archives of Dermatological Research.
For the study, researchers culled data on more than 250,000 participants from the All of Us Research Program, an NIH initiative that collects health information from patients across the United States.
Among the participants analyzed in the study, researchers found that those with psoriasis had a 1.5-fold increase in odds of an OCD diagnosis.
Exactly how the two conditions are linked is not fully understood, but researchers have their theories. It’s possible that symptoms associated with psoriasis might put patients at greater risk for developing OCD. Still, it’s also possible that certain OCD-related tendencies, such as too much bathing or handwashing, could exacerbate psoriasis.
“Excessive bathing can dry the skin and flare psoriasis. The itch of psoriasis can lead to a lot of scratching that can become a compulsion,” says study author Jeffrey Cohen, MD, an Assistant Professor of Dermatology at Yale School of Medicine in New Haven, CT, in a news release
Inflammation could also play a role. OCD and psoriasis are associated with elevated levels of inflammatory cytokines, such as interleukin (IL)-2, IL-6, and tumor necrosis factor-alpha (TNF-α), that play a role in the body’s immune response. Dr. Cohen believes this could be significant, especially considering genetic evidence that shows family members of people who have OCD have higher rates of immune-mediated diseases, such as skin conditions that include psoriasis.
Though the same OCD-psoriasis association had previously been found in Taiwanese and Swedish populations, this study was the first to demonstrate the link in American adults.
The All of Us database collects health information from U.S. patients of various races, ethnicities, ages, gender identities, sexualities, and other classifications. This provides researchers access to a highly valuable and vastly underrepresented data pool.
“It remains a really great database to use for this because it has information about a lot of people from diverse groups across the United States, and the data that’s there is quite powerful,” says Dr. Cohen.
Dr. Cohen has been using All of Us data since 2021 to study other associations, such as eczema and eating disorders, and atopic dermatitis, and OCD.
“In dermatology, we’re not that great at asking about certain mental health disorders that may be relevant,” says Dr. Cohen. “But if we identify it, if we see that someone might be at risk, we could put the wheels in motion to try to get them thoroughly evaluated and, if needed, treated for whatever it is that’s going on, in addition to what we’re doing for their skin.”
