One of the challenging aspects of psoriasis, and a hallmark of an autoimmune disease, is chronic inflammation. Historically, psoriasis has been characterized as a disease of the skin, but research over the past few decades has demonstrated that psoriasis is an autoimmune disease. While the primary presentation of psoriasis involves the skin, it impacts systems throughout the body. People with psoriasis have a dysregulated immune system, which leads to chronic inflammation. Chronic inflammation affecting skin means that people with psoriasis often experience frequent flare-ups, even when treatment leads to significant clearance of plaques.
Chronic inflammation of psoriatic disease (psoriasis and psoriatic arthritis), in turn, can affect the joints, the heart, and eyes of people with psoriasis. In addition to these affected body parts, other symptoms of chronic inflammation in people with psoriasis include fatigue, depression, inflammatory bowel disease, and vascular inflammation. Although each of these conditions and symptoms has complex and various mechanisms of action, some of the same inflammatory pathways are involved, so researchers believe inflammation may a common element that links these diverse symptoms.
The exact reason why chronic inflammation and bodily fatigue are linked is not completely understood, yet there is some research that helps illuminate the connection between fatigue and psoriasis. The research to date focuses on the potential for biologic treatments for plaque psoriasis to lessen fatigue along with clearance of skin symptoms. Although there is some evidence that fatigue symptoms can be improved with psoriasis treatment, this research doesn’t identify causal factors.
One challenge of this research is that fatigue levels do not seem to correlate with disease progression or severity. This could be why even when you are experiencing more skin clearance, or when you’re not in a current flare-up, you may still feel high levels of fatigue.
Read more about fatigue and psoriasis.
Because living with psoriasis can affect a person’s emotional health, people with the condition are at a higher risk of developing mental health conditions such as clinical depression. The emotional stress of living with psoriasis can be a main cause of depression for some people. However, new research suggests that depression may also be linked to the same inflammation that causes psoriasis skin symptoms. For example, researchers believe that depression can actually make inflammation worse and that inflammation itself can cause depression, creating a vicious cycle. This may be a reason that people who have inflammatory conditions of any kind are more likely to experience symptoms of depression.
Read more about the link between psoriasis inflammation and depression.
Inflammatory Bowel Disease
Psoriasis and inflammatory bowel disease (IBD) are both conditions with symptoms that are caused by inflammation due to an overactive immune system. Researchers believe that there is a genetic link between the two conditions—that people carry specific genes that affect the immune system’s functioning and make people with those genes more likely to develop both conditions.
Research also suggests that people who have both psoriasis and psoriatic arthritis had an even higher risk of inflammatory bowel disease than people who have psoriasis but no psoriatic arthritis diagnosis. One of the first symptoms people with psoriasis may experience before they are aware they have IBD is gastrointestinal pain.
The current theory is that these diseases develop when a person’s immune system has the genetic tendency to overreact to harmless microorganisms in the gut, what is called the microbiome. This reaction can cause chronic inflammation anywhere along the digestive tract. IBD includes both Crohn’s disease (CD) and ulcerative colitis (UC). The differences between CD and UC have to do with the location and severity of the symptoms.
Read more about the connection between psoriasis and IBD.
Another symptom, or set of symptoms of chronic inflammation in psoriasis, is vascular inflammation. This type of inflammation is often a hidden risk, but potentially deadly, as vascular inflammation can significantly increase the risk of heart disease. Clinical studies have shown that people with plaque psoriasis as well as those with psoriatic arthritis have heightened levels of vascular inflammation. This research has shown elevated levels of cholesterol, high blood pressure, and calcification of arteries.
Researchers are still working to understand exactly why and how people with psoriasis tend to have a higher risk of cardiovascular diseases. Currently, they think that the type of inflammation that causes the production of excess skin cells in people with psoriasis is also related to the process of atherosclerosis.