Scientists have linked irritable bowel syndrome to the risk of psoriasis

Irritable bowel syndrome (IBS) may be associated with an increased risk of developing psoriasis in later years. The researchers came to this conclusion after analyzing data from 437,170 participants in the British biobank who did not have psoriasis at the time of the start of the follow-up. About how much higher the risk turned out to be and what common mechanisms can link irritable bowel syndrome and psoriasis, see the Izvestia article.

The risk was higher by 35%

The study, the results of which are published in the Journal of Global Health (JoGH), involved 437,170 people without psoriasis at the time of follow-up. Among them, 21,748 people had irritable bowel syndrome. During the median follow-up period of 14.4 years, psoriasis was first diagnosed in 4,325 participants. The cumulative incidence of the disease was 0.88% in the group with IBS and 0.69% among people without the syndrome.

A higher risk associated with IBS was generally observed in different subgroups by age, gender, level of socio-economic deprivation, smoking, taking anti-inflammatory drugs, C-reactive protein levels, and genetic predisposition to psoriasis. However, the authors emphasize that the study reveals a statistical link between the conditions, rather than proving that IBS directly causes psoriasis.

What can unite the intestines and the skin

The authors note that IBS and psoriasis may have common pathophysiological pathways, including immune regulation disorders, intestinal microbiota imbalance, and changes in the gut—skin axis. Previous studies have also reported a link between the two diseases, but they had limitations, including a small sample size and design features that made it difficult to assess cause-and-effect relationships.

The new work is based on data from a large prospective study. The participants were divided into groups depending on the presence of IBS at the time of inclusion, after which the scientists tracked cases of newly diagnosed psoriasis. The follow-up continued until diagnosis, death, or loss of a participant for further follow-up or, accordingly, completion of the study.

The scientists conducted additional analyses to verify the stability of the results. The increased risk persisted after excluding cases of psoriasis diagnosed during the first or first two years of follow-up, as well as after accounting for anxiety and depression, a genetic predisposition to psoriasis, a healthy diet, and other factors.

What is psoriasis and why does it appear?

Psoriasis is a chronic skin disease in which skin cells form faster than usual. As a result, they accumulate on the surface and form characteristic areas of inflamed, dry and flaky skin. The exact cause of the disease is unknown, but experts attribute it to a malfunction of the immune system. Heredity can also play a role: psoriasis is more likely to develop if close relatives have the disease.

The most common symptom is dry, itchy and painful skin areas covered with silvery-white scales. They can appear on different parts of the body, but the scalp, elbows, knees, trunk and the area behind the ears are especially often affected. Psoriasis can also affect nails. The course of the disease usually changes: periods of exacerbation are replaced by periods of improvement.

Various factors can provoke an exacerbation in a person with a predisposition. These include stress, smoking, alcohol consumption, certain medications, infections, and skin damage. At the same time, psoriasis is not contagious — it is impossible to transmit it to another person. In some patients, the disease is also accompanied by psoriatic arthritis, which causes inflammation of the joints.

Why the skin should be monitored for IBS

The authors believe that the results indicate the need to pay attention to the possible development of psoriasis in patients with irritable bowel syndrome. In their opinion, the revealed relationship can help in further studying the common pathophysiological mechanisms of the two conditions and developing preventive and therapeutic strategies.

However, the study does not allow us to say that irritable bowel syndrome causes psoriasis. Scientists have found that people with IBS have a statistically higher long-term risk of developing skin disease. Further research is needed to understand the reasons for this relationship.